Following the first reports of coronavirus disease-19 (COVID-19) by China to the World Health Organization (WHO) on 31st December 2019, more than 4,302,774 novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) cases have been reported by authorities in 212 countries and territories by 12th May 2020. The outbreak and spread of COVID-19 worldwide, highlights the critical need for developing rapid and accurate diagnostic testing methods for emerging human coronavirus (CoV) infections. Testing is crucial to track the spread of disease during a pandemic, and to swiftly permit public health interventions including isolation, quarantine, and appropriate clinical management of afflicted individuals. The key components of viral diagnostic tests are (1) collection of the appropriate sample , (2) availability of the genetic and proteomic sequences of the novel virus for analysis, and (3) rapid and accurate laboratory testing methods. The current gold standard for the molecular diagnosis of SARS-CoV-2 infection is the real-time reverse transcriptase-polymerase chain reaction (RT-PCR) for the qualitative and quantitative detection of viral nucleic acids. Other relevant laboratory methods include enzyme-linked immunoassays (EIA) for viral antibody and antigen detection, and serum viral neutralization (SVN) assays for antibody neutralization determination. The challenges faced in developing a diagnostic test for a novel pathogen are the ability to measure low viral loads for early detection, to provide low or no cross-reactivity with other viral strains and to deliver results rapidly. Several point-of-care molecular devices are currently being integrated for fast and accurate diagnosis of SARS-CoV-2 infections. This review discusses the current laboratory methods available to test for coronaviruses by focusing on the present COVID-19 outbreak. Coronavirus disease-19 (COVID-19) is caused by a novel coronavirus (CoV) that was originally reported in Wuhan, Hubei province, China in December 2019 , group IV virus. The genome was sequenced from the bronchoalveolar lavage fluid of a patient (Genbank: MN908947) and shared through the Global Initiative on Sharing All Influenza Data (GISAID) platform on 12th January 2020  as positive controls and to generate standard curves. An internal control using RNAse P (RP) verifies the presence and quality of nucleic acid in samples and molecular grade nuclease-free water is used as a negative amplification control. A negative patient sample serves both as a negative extraction control to monitor cross contamination across samples and to validate test reagents.RNA is reverse transcribed to cDNA and subsequently amplified using a real-time quantitative PCR instrument. WHO announced various primer and probe sets for SARS-CoV-2 previously developed in China, Germany, Hong Kong, Japan, Thailand, and USA  is necessary to ensure there is no homology with other CoVs like SARS-CoV from 2003 or other organisms such as False-negative results could potentially arise from mutations occurring in the primer and probe target regions in the SARS-CoV-2 genome. Negative results do not preclude SARS-CoV-2 infection, and results should be validated with different primer sets against the same gene target and combined with patient history and other clinical data to accurately determine patient infection status.Provisions for testing laboratories, the use of approved tests and validation of results with governing authorities to develop master protocols for use by multiple investigators must be in place to achieve rapid testing capacity. The output for number of tests per day and number of individuals tested per day relies on the laboratory capacity, trained staff, reagents, supplies and equipment. Large quantities of specific high-grade reagents are needed to perform tests and supplies can be quickly depleted in a pandemic. This impacts the turnaround time for RT-PCR diagnostic testing that ranges between 2 and 5 days. Strategies to rapidly scale up testing for novel HCoVs must be considered for future diagnostic testing.(ELISAs) for antibody detection against SARS-CoV-2 measure the host humoral response including IgM, IgG, and IgA to define previous exposure to the virus  is bound to the SARS-CoV antibodies for signal detection by substrate addition, and quantification.Antibody tests provide the advantage of a simple method of detection of SARS-CoV-2 antibodies and are convenient to compare multiple samples from a single patient. Positive rates of detection for SARS-CoV-2 IgG in patients by ELISA measurements are 85.4% and 75.6–93.1% for IgM  does not necessarily guarantee immunity against reinfection. Negative results do not rule out SARS-CoV-2 infection, particularly in those who have been in contact with the virus and positive results may be due to past or present infection with SARS-CoV  that can alter epitopes and protein conformation . This expedites the assessment and optimization of these diagnostic tests, with the expectation that any test is sufficiently experimentally validated before it is made available to patients. If these tests do not provide accurate results, this can impair prevention efforts and delay appropriate treatment during the global pandemic response.Several research laboratories have used the EIA platform to develop lateral flow immunoassays (LFIA) for the rapid qualitative detection of SARS-CoV. This is designed as a simple, portable diagnostic strip to measure either SARS-CoV-2 antibodies or antigens. As viral titers are often low in nasal swabs and serum or plasma, detection of antigens may be more challenging in comparison to detection of antibodies. Serological antigen assays can target S1 and S2 domains of the S protein that binds angiotensin-converting enzyme-2 (ACE-2), an integral transmembrane protein in the lung alveolar epithelium that serves as the initial attachment site for SARS-CoV-2, or N proteins.The design of the lateral flow test is that of a strip/dipstick containing immobilized test reagents, enclosed in a cassette. Drops of a patient's blood are deposited on the strip which contains a coating of purified monoclonal antibody (mAb) or recombinant antigen that is localized at specific regions on a nitrocellulose membrane. The mAb targets a viral antigen; the recombinant antigen is recognized by antibodies that are present in infected patients. The strip also contains labeled detector antibodies that bind the same antigen. A positive antibody result indicates binding between the coating antigen and patient antibodies and binding by the detector antibody. This generates a colored signal. A positive antigen result indicates binding between the coating antibody and patient antigen.Two drops of blood are sufficient for detection of SARS-CoV-2 and antibodies by this method. This technique delivers results in ~15 min, and uses visual detection by the naked eye in comparison to RT-PCR (2–5 days). Detection of antibodies shows previous viral exposure while detection of antigens indicates active carriers of SARS-CoV-2 virus. The specificity and sensitivity of LIFAs are comparable for antibody and antigen assays.Tests to detect SARS-CoV-2 in patients by identifying viral antigens are more challenging to develop than tests to detect the neutralizing antibodies against SARS-CoV-2 (see below), as purified monoclonal antibodies must be generated against target antigens. Further, these assays need to be assessed and optimized using blood from infected patients.in silico models of antibody–antigen interactions that are used to generate artificial antibody libraries , Huh7 (human hepatoma cell line), 293T (human kidney cell line) , a single-tube technique for the amplification of DNA and reverse transcription-LAMP that combines reverse transcriptase and LAMP to detect RNA  for SARS-CoV-2  for signal amplification and nucleic acid detection. The Cas13a assay can be paired with target nucleic acid amplification for more sensitive results using an isothermal exponential amplification technique, most commonly RPA. This coupled technique is termed SHERLOCK (Specific High-Sensitivity Enzymatic Reporter unLOCKing) and allows fluorescence, colorimetric, lateral flow, and other readout approaches to enable the rapid detection of a variety of targets  guided detection method that is specific for RNA and is being applied for SARS-CoV-2 detection. A key feature of this approach is the Cas13a (formerly named C2c2) enzyme that recognizes and binds targeted RNAs in a sequence-specific manner followed by non-specific in vivo CRISPR tools, the Cas13a protein must be recombinantly expressed and purified. The endonuclease activity of purified Cas13a uses crRNA targeting sequences in the S gene and ORF1ab in SARS-CoV-2 RNA. Target site-recognition activates trans-cleavage of reporter probes resulting in increases in fluorescence output signals and confirming the presence of viral RNA. Using synthetic SARS-CoV-2 the reported performance of this method for detection of target sequences is 20–200 aM  enables complete sequencing of the ~30,000 nucleotides of the SARS-CoV-2 genome. NGS provides a method for identification of SARS-CoV-2, for environmental monitoring and surveillance testing, while also providing insight into strain origin and viral evolution. Each sequence is deposited into the GISAID EpiCoVTM Database and to date, there are over 17,000 SARS-CoV-2 sequences from global NGS efforts.RNA is extracted from clinical specimens, as for RT-PCR, and further purified to remove human cytoplasmic and ribosomal rRNA.RNA is fragmented followed by cDNA synthesis. Through the use of a set of highly specific, universal CoV primers, all genomic segments are amplified and the DNA amplicons are sequenced to deliver highly accurate SARS-CoV-2 typing in <24 h. Virus titer, efficiency of human rRNA depletion, and the number of reads per sample impact the number of virus-specific reads obtained and accurate coverage of the viral genome.Collectively, global NGS data suggest that SARS-CoV-2 genome is relatively stable, although mutations are being identified in symptomatic individuals that are not present in the original strain in Wuhan, China. Two recent NGS studies report a large base pair deletion consisting of 81 nucleotides in SARS-CoV-2 ORF7a in a virus sample from a US patient (Holland et al., Regulating authorities provide interim guidance on the handling of specimens associated with SARS-CoV-2 CDC, . SamplesOngoing research is critical to optimize existing antibody tests to determine whether immunity prevents recurrent infection and to investigate the efficacy of passive antibody therapies for COVID-19 infection. The identification of novel disease biomarkers may be valuable for understanding what makes people susceptible to COVID-19 infection and in predicting the severity and progression of disease, Researchers could request approval to analyze stored samples of human blood or in animals that might be a natural reservoir of the virus. Specifically, guidance would be needed to direct blood and plasma collection centers to allow access of samples from COVID-19 patients.The COVID-19 pandemic showcases how quickly information needs to be shared as responders address rapidly evolving situations. Establishing communication across laboratories worldwide helps to develop master protocols and establish reference panels for use by multiple investigators. This will aid in coordinating the collection and use of data, and regulatory infrastructure. Having a range of tests also puts less pressure on one manufacturer or supply chain, as different suppliers may use different materials. This could help alleviate difficult decisions to limit testing to the most vulnerable patients which can have great public health consequences.RD'C and VS contributed to concept and writing of manuscript. AC contributed to writing, and prepared tables and figure for this manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Therefore, we analyzed diagnostic and prognostic potential of the markers of early NEC pathogenesis, such as excessive inflammatory response (serum amyloid A (SAA)) and gut epithelium damage  and trefoil factor-3 (TFF-3)). We used ELISA to analyze these biomarkers in the urine of patients with suspected NEC, either spontaneous or surgery-related, or in infants without gut surgery (controls). Next, we compared their levels with the type of the disease (NEC or sepsis) and its severity. Already at the time of NEC suspicion, infants who developed NEC had significantly higher levels of all tested biomarkers than controls and higher levels of I-FABP and L-FABP than those who will later develop sepsis. Infants who will develop surgery-related NEC had higher levels of I-FABP and L-FABP than those who will develop sepsis already during the first 6 hours after the abdominal surgery. I-FABP was able to discriminate between infants who will develop NEC or sepsis and the SAA was able to discriminate between medical and surgical NEC. Moreover, the combination of TFF-3 with I-FABP and SAA could predict pneumatosis intestinalis, and the combination of I-FABP, L-FABP, and SAA could predict gas in the portal vein or long-term hospitalization and low SAA predicts early full enteral feeding. Thus, these biomarkers may be useful not only in the early, noninvasive diagnostics but also in the subsequent NEC management.Necrotizing enterocolitis (NEC) is a severe gastrointestinal disease affecting mainly preterm newborns. It is characterized by unexpected onset and rapid progression with specific diagnostic signs as  Necrotizing enterocolitis (NEC) is a severe acute gastrointestinal disease affecting mainly preterm newborns. The pathophysiology of NEC remains poorly understood. The main risk factors of NEC are immaturity of gut barrier and immune system together with enteral feeding and abnormal microbial colonization of the gut. On the other hand, breastfeeding represents an important factor protecting from NEC , 2. Thanpneumatosis intestinalis or gas in the portal vein, they appear rather later in the disease course and their absence must be interpreted with caution [With overall incidence of 1 to 3 cases per 1000 live births and mortality as high as 50% , NEC is The best biomarkers should be specific for the early steps in NEC pathogenesis. Since several studies demonstrated the advantages of biomarker combination in the NEC diagnosis, we combined analysis of several noninvasive markers of excessive inflammatory response and destruction of the gut mucosa, all typical features of NEC pathogenesis .Previously, we showed that urinary intestinal fatty acid-binding protein (I-FABP) can distinguish NEC from sepsis in early stage of the disease . Fatty aThe trefoil factor-3 (TFF-3) is expressed in intestinal tract and is associated with maintaining of mucosal barrier integrity, promotion of mucosal barrier restitution, gastrointestinal inflammation, and cell migration –23. TFF-Serum amyloid A (SAA) is an acute phase inflammatory protein. It increases in innate defence mechanisms in response to infection, inflammation, and trauma. The SAA was suggested to be more sensitive and specific marker of inflammation than C-reactive protein in various inflammatory conditions –30. The The aim of this study was to investigate the diagnostic potential of these gut-associated and inflammatory biomarkers in the early diagnostics of NEC, their association with clinically relevant and well-established disease-related parameters, and their capacity to predict the disease course. Thanks to their small size, all these biomarkers can pass through the kidney to urine, which gives unique opportunity to constant monitoring and noninvasive measurement.n = 20) and sepsis group (n = 9) using the standard criteria for NEC  or sepsis  [In the study, we enrolled 29 patients with suspected NEC and 8 healthy infants without gut surgery and intestinal mucosa disruption as controls. All of them were recruited from the individuals admitted to the Department of Pediatric Surgery of Motol University Hospital, Prague, Czech Republic, between April 2012 and December 2014 . The incculture) , 35. Perculture) . MoreoveUrine samples were collected for two days in 6-hours intervals starting at the time of enrolment to the study or already after the surgery for congenital intestinal malformation to evaluate the biomarker dynamics in infants before the suspicion of NEC. These samples were analyzed retrospectively in those who developed NEC or sepsis. The urine was collected either using urine bag connected to an indwelling catheter or from a cotton wool swab placed in the diaper and squeezed through a syringe barrel into a collection tube. The urinary creatinine was measured in each sample immediately after sampling and samples for biomarker analyses were frozen at −20°C.The concentrations of biomarkers were measured by ELISA , which ip < 0.05. Regression analysis was performed in R and the effect of each biomarker on Akaike information criterion (AIC) was determined in the nnet package (ver. 7.3-12). Next, we performed both backward elimination and forward selection based on AIC to determine the best regression model to discriminate between the two states . Thus, we found minimum models with best prediction and performance capacity, which were used for construction of receiving operating characteristic (ROC) curves. The ROC curves and their area under curve (AUC) were calculated using ROCR package (ver. 1.0-7). Hierarchical clustering and heat map construction was performed using the Kendall distance calculating method in the ComplexHeatmap (ver 1.3) package for R [The differences between studied groups were analyzed by nonparametric Mann-Whitney test. Continuous variables are presented as mean ± standard deviations (SD) and dichotomous variables as percentages. Statistical analyses were performed using GraphPad Prism statistical software  and differences were considered statistically significant at ge for R .During the first 6 hours after the enrolment, infants who will later develop NEC (NEC group) had significantly higher urinary I-FABP, L-FABP, TFF-3, and SAA when compared with healthy infants and higher levels of I-FABP and L-FABP than those who will later develop sepsis (sepsis group) . Similarpneumatosis intestinalis and the combination of I-FABP with L-FABP and SAA predicted portal venous gas , which is associated with gut perforation, had elevated both SAA and TFF-3 in comparison with infants with stages IIA, IIB, and IIIA NEC  . The SAA Figures . Perinat Figures .Next, we analyzed the ability of these noninvasive biomarkers to predict clinical outcome in infants who will develop NEC. The urinary I-FABP and L-FABP were significantly higher in infants with long hospitalization (more than 19 days), and when combined with SAA, they can predict long hospitalization . While LIn our previous study, we found that both, serum and urinary I-FABP, can distinguish NEC from sepsis in the early stage of the disease, and the addition of I-FABP analysis to the diagnostic gold standard for NEC (X-ray and ultrasound) can significantly increase the sensitivity and negative predictive value . Here, wIn this study, we found that not only I-FABP but also L-FABP, SAA, and TFF-3 were significantly higher in the urine of infants who will later develop NEC in comparison with healthy infants already in the first 6 hours after the NEC suspicion. Their high levels suggest that gut mucosa damage and strong inflammatory response are detectable even before the full spectrum of NEC symptoms is apparent. The increase of I-FABP and L-FABP in NEC infants suggests that they are both associated with the gut epithelium damage. This is in agreement with findings that L-FABP has similar pattern of tissue distribution with higher tissue content than I-FABP . TherefoOur finding that high levels of urinary TFF-3 are associated with NEC is in agreement with previous findings, where the elevated plasma TFF-3 was associated with intestinal damage in NEC . Increaspneumatosis intestinalis  and portal venous gas  already in the first 6 hours after the enrolment. In our previous study, we showed that currently used gold-standard methods for NEC diagnosis have low sensitivity and negative predictive value. This may cause the late diagnosis of NEC, which is accompanied with poor outcome or risk of death [Next, we analyzed if these biomarkers are associated with clinically relevant and well-established disease-related parameters in NEC. We found that SAA not only distinguished infants who will develop NEC stage II and III, it can also distinguish infants who will develop the most severe stage associated with gut perforation—stage IIIB NEC  from stage IIA, IIB, and IIIA NEC  at the time of NEC suspicion. This is in agreement with a previous study finding urinary SAA correlated with diseases severity . We alsoof death –46. Moreof death . Our newThe hypoxic ischemia was described as a one of the risk factor in NEC pathogenesis . It may If these biomarkers reflect the pathogenesis and disease severity, they may predict outcome of the disease. Indeed, we found that higher levels of I-FABP, L-FABP, and SAA predict shorter hospitalization already in the first 6 hours from NEC suspicion. This is in agreement with previous observation that serial I-FABP measurement can predict development of complicated disease and that SAA in serum is useful tool for determining the disease severity and response to therapy in infants with NEC , 53. We Development of NEC, its severity, and its consequences can be predicted using the panel of pathogenesis-relevant biomarkers before the symptoms became clinically apparent. The early diagnosis and prediction are useful for the management of NEC by the frontline clinicians.


Cerebral microhaemorrhages are increasingly being recognised as a complication of COVID-19. This observational retrospective study aims to further investigate the potential pathophysiology through assessing the pattern of microhaemorrhage and clinical characteristics of patients with COVID-19 and microhaemorrhage. By comparing with similar patterns of microhaemorrhage in other non-COVID-19 disease, this study aims to propose possible common pathogenic mechanisms.A retrospective observational case series was performed identifying all patients with COVID-19 complicated by cerebral microhaemorrhage on MRI. The distribution and number of microhaemorrhages were recorded using the microbleed anatomical scale, and patients’ baseline characteristics and salient test results were also recorded.Cerebral microhaemorrhages were noted to have a predilection for the corpus callosum, the juxtacortical white matter and brainstem. All patients had a preceding period of critical illness with respiratory failure and severe hypoxia necessitating intubation and mechanical ventilation.This study demonstrates a pattern of cerebral microhaemorrhage that is similar to the pattern reported in patients with non-COVID-19 related critical illness and other causes of severe hypoxia. This raises questions regarding whether microhaemorrhage occurs from endothelial dysfunction due the direct effect of SARS-CoV-2 infection or from the secondary effects of critical illness and hypoxia. Numerous reports have highlighted different neurological complications of COVID-19, including cerebrovascular disease, encephalopathy and peripheral neuropathy.White matter microhaemorrhage (MH) has been reported as a radiological presentation in COVID-19.This retrospective observational case series was approved by local ethics review. Patient data were anonymised at the point of analysis, and the need for informed consent was waived. Patients who underwent brain MRI between 1 April 2020 and 1 June 2020 with a confirmed diagnosis of SARS-CoV-2 infection (on reverse transcriptase PCR assay of an airway tract sample) were identified using searches of electronic health records at a university-affiliated hospital. MRI examinations were performed according to a routine brain protocol, which included a susceptibility-weighted sequence. The susceptibility-weighted sequence technique varied across scanners. Two radiologists collectively reviewed the imaging, and a third radiologist reviewed the cases independently. If there was disagreement, cases were reviewed jointly for consensus opinion. Patients were included in the case series if they had tested positive for SARS-CoV-2 prior to the MRI and had MH on their MRI, which was separate to other CNS pathology such as ischaemic stroke. The location and volume of MH was scored according to the microbleed anatomical scale  and manually mapped to a simplified brain diagram. These diagrams were used to generate a heatmap of composite MH distribution across all patients, as described elsewhere.We identified 30 MR brain scans performed on 28 adult patients with confirmed COVID-19 between 1 April and 1 June 2020. Of these, 10 patients were noted to have MH distinct from other central nervous system (CNS) pathology.MRI was of diagnostic quality in 9 of the 10 patients. In one patient, imaging was degraded by motion artefact, and therefore, MH could not be quantified accurately. All 10 patients demonstrated MH in the corpus callosum with a predilection for the splenium. In the nine MRIs included in the quantitative assessment , the medPatient clinical features are summarised in The median time to MRI scan was 37.5 days after admission (range: 24–59 days). Indications included altered mental state (6/10), weakness (1/10), seizure (1/10), tremors (1/10) and an abnormal brainstem pattern of ventilation (1/10). Seven out of 10 patients required haemodialysis or haemofiltration for acute kidney injury. One patient needed extracorporeal membrane oxygenation (ECMO) for refractory T1RF. All patients received antithrombotic therapy with heparinisation.All patients had recorded periods of acidosis, raised lactate dehydrogenase, anaemia, lymphopaenia and neutrophilia. Nine of the 10 patients had episodes of acute kidney injury. All patients had raised CRP, ferritin and high D-dimer. Nine patients had high fibrinogen, and five patients had mildly prolonged prothrombin time.All patients were alive at the time of this report, and all had been discharged from critical care. At the time of discharge abnormal laboratory findings had improved or normalised for all patients.We present a case series of 10 patients with COVID-19, abnormal neurology and a common distribution of white matter MHs, with a predilection for the splenium of the corpus callosum. This pattern of MH is unusual and distinct from the typical MH distributions in other causes, in particular it would not fit diagnostic criteria for either hypertensive arteriopathy or amyloid angiopathy.Cerebral MH occurs secondary to endothelial dysfunction causing focal extravasation of red blood cells into the brain.Severe COVID-19 is associated with a hyperinflammatory syndrome and cytokine storm, which itself is thought to mediate endothelial dysfunction and coagulopathy.2) of 6.8, which is equivalent to the PaO2 at an altitude of 5000 feet.Comparison with other accepted causes of MH may also help illuminate pathogenesis. A similar distribution of MH has been described in mountaineers who develop high-altitude cerebral oedema (HACE) and in patients with non-COVID-19 related respiratory failure and critical illness.Aside from pathogenesis, the long-term influence of COVID-19 related MH on cognitive, neurological and psychological outcomes are also unknown. In other diseases, MH has been independently associated with cognitive impairment and disability.This study adds weight to previous work demonstrating a common but unusual pattern of cerebral MH in critically ill patients with COVID-19. As a small case series, there are however limitations. Patients were retrospectively selected for the specific finding of MH creating a selection bias. Second, as imaging was performed as part of routine clinical care, MRI scans were performed at different time points within the patients clinical course. Resultantly, MRIs were likely performed several days to weeks after the neurological event as the neurological presentations were probably concealed by sedation and only apparent on weaning. Finally, there were differences in the susceptibility-weighted sequence employed that had different sensitivities to MH limiting comparison between patients.In conclusion, we present further evidence of a distinctive pattern of MH in COVID-19. Whether direct effects of SARS-CoV-2, systemic inflammation, coagulopathy or hypoxia mediate the MHs observed in COVID-19 remains unclear. The observation that the same pattern of MH is also seen in high altitude exposure and different types of critical illness perhaps implies that COVID-19 associated MH is a more phenomenon of hypoxia and critical illness as opposed to a unique feature of SARS-CoV-2 infection. Various discussed mechanisms may contribute to a final common pathway of endothelial dysfunction and blood–brain barrier breakdown. Further larger series and prospective case–control studies are needed to better understand the pathogenesis of COVID-19 related MH. Long-term follow-up is also needed to assess the impact on cognitive and functional outcome.


As a new decade began, COVID-19 quickly gained importance as it became the cause of the current global pandemic. Research has been focusing on studying the structure of SARS-CoV-2 and investigates possible pharmaceutical approaches. With the number of cases increasing every day, globally, multiple drugs are being researched as possible candidates. Although multiple drugs show promise in the treatment of COVID-19 via either inhibiting viral replication or preventing fusion of the virus to the ACE2 receptors, further investigation is still warranted and necessary before the admission of any type of pharmaceutical agent. Furthermore, several supplements have also been documented in being utilized as treatment of COVID-19. The exact mechanism and efficacy of current candidate drugs are still being explored through clinical trials. Despite the advancements in current research with emerging treatments, social distancing and engaging in preventative measures remains crucial to attempt to prevent the occurrence of more cases and deaths, worldwide. This review explores various drugs and their mechanism of action which are either currently being used in clinical trials or may be used in the future for the treatment of COVID-19. Since the emergence of the virus in China in December of 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread across the globe resulting in the current global pandemic. As of March 12, 2020, COVID-19 has been confirmed in 125,048 people worldwide, carrying a mortality rate of approximately 3.7%, compared to the mortality rate of less than 1% from influenza [The global pandemic related to SARS-CoV-2 originated in Wuhan, China in December 2019 and was thought to have a zoonotic transmission with bats being the reservoir host. SARS-CoV-2 is an enveloped virus with a large positive-stranded RNA genome. On the surface of the virus is a spike protein; a type I membrane glycoprotein that constitutes peplomers and plays an integral role in the initiation of viral infectivity . Once thThere is an increased amount of pressure prevalent within the scientific and medical communities in attempting to find a proper medical strategy in managing and treating COVID-19. Several drugs are currently being researched that seem to be promising in the treatment of COVID-19, however, it should be noted with caution that these medical interventions are still being researched as no one approach has been solidified. Several antimicrobials and antivirals are currently being researched and investigated as they inhibit various steps within the lifecycle of SARS-CoV-2, as will be discussed. Supplements such as vitamin C and zinc are also under trial. While some of these pharmaceutical agents are administered as an independent dose, multiple drugs are co-administered. Although the mechanism of action amongst several agents may be similar, the adverse effects and the recommended dosing differ substantially. For each pharmaceutical agent reviewed, there will be an extensive focus on the mechanism of action and adverse effects along with any dosing recommendations that may have been explored.Camostat mesylateCamostat mesylate is a potent serine protease inhibitor that is approved for the treatment of pancreatic inflammation in Japan . SARS-CoArbidolArbidol  is a promising repurposed antiviral agent with a unique mechanism of action targeting the S protein/ACE2 interaction and inhibiting membrane fusion of the viral envelope to the host cell . ArbidolChloroquine/HydroxychloroquineCurrently, chloroquine/hydroxychloroquine is one of the most promising compounds that has gained international attention for its potential activity against COVID-19 . ChloroqLopinavir and ritonavirLopinavir is a human immunodeficiency virus (HIV)-1 protease inhibitor administered in fixed-dose combination with ritonavir, a potent CYP3A4 inhibitor that ‘boosts’ lopinavir concentrations . The useIvermectinIvermectin has been identified very largely in the search for appropriate pharmaceutical intervention in COVID-19. Ivermectin is an FDA-approved broad-spectrum antiparasitic agent that in recent years, has shown to have antiviral activity against a broad range of viruses in vitro . IvermecRibavirinRibavirin, a guanine analog, inhibits viral RNA-dependent RNA polymerase . RibavirRemdesivirRemdesivir, a broad-spectrum antiviral, is another potential drug that is under investigation for the treatment of COVID-19. Animal experiments indicate that remdesivir can effectively reduce the viral load in lung tissue of mice infected with MERS-CoV, improve lung function, and alleviate pathological damage to lung tissue . RemdesiFavipiravirFavipiravir is a prodrug of a purine nucleotide, favipiravir ribofuranosyl-5’-triphosphate that inhibits the RNA polymerase, halting viral replication . In addiTocilizumab and sarilumabTocilizumab, as immunotherapy, is a humanized anti-interleukin 6 monoclonal antibody for the treatment of rheumatoid arthritis ,27. It iOseltamivir and baloxavirGiven their antiviral activity against influenza, considerable attention has been paid to oseltamivir, and a lesser degree baloxavir, as potential treatment options for COVID-19 . OseltamAs the outbreak of COVID-19 continues to create fear within the medical community, investigating all possible pharmaceutical options is necessary. Several different pharmacological options are constantly emerging and looking into each of the interventions is crucial in attempts to contain the current pandemic. Currently, there are no fully verified antiviral drugs or vaccines that are specific to fighting SARS-CoV-2. Many pharmaceutical approaches being currently explored are those that have been used for various different conditions. The repurposing of these drugs provides hope that a cocktail of drugs currently on the market may appropriately target various steps in the lifecycle of SARS-CoV-2, allowing for the ultimate degradation of the virus. Decreasing the viral load by destabilizing the RNA-dependent RNA polymerase will hinder the replication of the virion, and ultimately, decreasing the infectivity of SARS-CoV-2. Other approaches focus on impairing the fusion of SARS-CoV-2 with the type II pneumocytes ACE2 receptor. Inhibiting fusion prevents any type of destruction of the type II pneumocytes, eliminating any type of infectivity of the virus. It should be noted that almost all the pharmaceutical approaches are currently being further researched through clinical trials. These clinical trials will ultimately provide insight into the efficacy and safety of these candidate drugs, thus providing the medical field with appropriate alternatives to treating those infected by this pandemic.


Eating disorder is highly associated with obesity and it is related to brain dysfunction as well. Still, the functional substrates of the brain associated with behavioral traits of eating disorder are underexplored. Existing neuroimaging studies have explored the association between eating disorder and brain function without using all the information provided by the eating disorder related questionnaire but by adopting summary factors. Here, we aimed to investigate the multivariate association between brain function and eating disorder at fine-grained question-level information. Our study is a retrospective secondary analysis that re-analyzed resting-state functional magnetic resonance imaging of 284 participants from the enhanced Nathan Kline Institute-Rockland Sample database. Leveraging sparse canonical correlation analysis, we associated the functional connectivity of all brain regions and all questions in the eating disorder questionnaires. We found that executive- and inhibitory control-related frontoparietal networks showed positive associations with questions of restraint eating, while brain regions involved in the reward system showed negative associations. Notably, inhibitory control-related brain regions showed a positive association with the degree of obesity. Findings were well replicated in the independent validation dataset (n = 34). The results of this study might contribute to a better understanding of brain function with respect to eating disorder. Eating disorder is one of the important factors underlying obesity –3, whichThe association between brain alterations and eating disorders can be effectively explored using neuroimaging modalities such as functional magnetic resonance imaging (fMRI), positron emission tomography (PET), and single-photon emission computed tomography (SPECT) ,9–11. HoMachine learning is widely used in neuroimaging and medical field, and we applied one of machine learning technique, canonical correlation analysis (CCA), for data analysis ,17. CCA We adopted a functional connectivity analysis based on graph theory to estimate brain function ,32. GrapIn the current study, we aimed to investigate the multivariate association between the functional connectivity of all brain regions and eating disorders at question-level using the SCCA approach. Our study is not limited to assess obesity-related eating disorders in the obese group, rather we aimed to associate functional connectivity of brain regions and behavioral patterns of eating disorders in a general population. The results of this study might contribute to a better understanding of brain function with respect to eating disorder.3 voxel resolution, and 176 slices. Those of the rs-fMRI data were as follows: TR = 645 ms, TE = 30 ms, flip angle = 60°, FOV = 222 mm × 222 mm, 3 mm3 voxel resolution, 40 slices, and 900 volumes. Among the total of 650 participants, 320 participants have full demographic information, obesity-related clinical scores (body mass index [BMI] and waist-to-hip ratio [WHR]), and TFEQ scores. BMI and WHR are calculated from the vitals  that were recorded by staff with a standardized procedure. Thirty-six subjects with medical conditions  were excluded and total 284 participants were considered in this study. Detailed demographic information is reported in This study was a retrospective analysis of anonymized data and institutional review board (IRB) approval was obtained at Sungkyunwkan University. All data were obtained with informed written consent in accordance with established human subject research procedures expressed in the Declaration of Helsinki. Our study was performed in full accordance with the local IRB guidelines. For the discovery set, the T1-weighted structural MRI and resting-state fMRI (rs-fMRI) data were obtained from the enhanced Nathan Kline Institute-Rockland Sample database . All ima3 voxel resolution; and 160 slices. Those of the rs-fMRI data were as follows: TR = 2490 ms; TE = 30 ms; flip angle = 90°; FOV = 220 mm × 220 mm; 3.4 × 3.4 × 3.0 mm3 voxel resolution; 36 slices; 150 volumes.Data obtained from Saint Vincent’s hospital in South Korea was used for validation. All data were obtained with informed written consent in accordance with established human subject research procedures expressed in the Declaration of Helsinki. Our study was performed in full accordance with the local IRB guidelines. The dataset includes T1-weighted data, rs-fMRI, full demographic information, BMI, WHR, and Eating Attitudes Test (EAT-26) scores of 34 participants [The eating disorder scores were measured using the TFEQ, which contains a total of 51 questions . All theEAT-26 is a reliable screening tool for eating disorders –38 and iThe T1-weighted structural data and rs-fMRI data were preprocessed using a Fusion of Neuroimaging Preprocessing (FuNP) pipeline that integrates AFNI, FSL, and ANTs software –42. The β, where r is the correlation coefficient and β is the scale-free index that was set to six [Graph theory-based functional connectivity analysis was adopted in this study. Graph nodes were the brain regions defined by the Brainnetome atlas  and the t to six ,49. The t to six ,32. The u and v) of two feature matrices, X and Y, by maximizing the correlation between the linear combinations of the features from two matrices (Xu and Yv), where X is the betweenness centrality values of all brain regions (n × 246 regions), Y is the responses to all questions in the TFEQ assessment (n × 51 questions), and n is the number of participants. L1 regularization was used to control the sparse relationship between the two different feature matrices [u and βv) using five-fold cross-validation where the built SCCA model from the training fold was tested using various beta values in the left-out fold to maximize the canonical correlation. The final beta values were determined by averaging them across the cross-validation. The SCCA is a multivariate approach, which aims to optimize the association between one set of variables  and another set of variables  by maximizing the canonical correlation between the linear combination of a subset of each variable and relevant loading vector. This approach does not involve multiple tests of univariate statistics and therefore, we evaluated the model just once. Thus, there are no corrected p-values in that sense. Bootstrapping was performed in order to assess the reliability of the results, randomly selecting 80% of subjects for 1000 times. The loading vectors were computed for each bootstrapped subset and the frequently selected features were compared with those obtained from the full data.The multivariate association between the functional connectivity of the whole brain and eating disorders was explored using the SCCA approach. The betweenness centrality values of 246 brain regions and responses of 51 questions in TFEQ assessment were considered . The goamatrices . The objPost-hoc correlation analysis between the betweenness centrality values of the identified brain regions, which showed an association with eating disorders, and the obesity-related clinical scores of BMI and WHR was conducted at two levels, one at the large-scale network and the other at the smaller-scale region . This waIndependent validation was conducted using data of the Saint Vincent’s hospital in Suwon, South Korea. The betweenness centrality was calculated from rs-fMRI data and the same atlas was used. SCCA was applied to the centrality values of 246 brain regions and responses to 26 questions of EAT-26. The optimal regularization parameter was obtained in the same way described before, but three-fold cross-validation was used in parameter tuning due to the small sample size.Twenty-seven brain regions and 19 questions were selected as a result of the SCCA. The canonical correlation coefficient between two linear combinations of two features was 0.4945. The brain regions with a large magnitude of the loading vector  were primarily located at the frontoparietal and limbic networks that process cognition- and reward-related functions . The queBootstrapping was performed for 1000 times and the frequently selected features were compared with those from the main results. Twenty-seven selected brain regions of the main results were compared with the top 27 frequently selected brain regions from the bootstrapping. A total of 21 regions (77.78%) overlapped. Nineteen selected questions of the main results were compared with the top 19 frequently selected questions from the bootstrapping. A total of 18 questions (94.74%) overlapped and overlapped features were mostly assigned in dietary restraint. The list of the most frequently selected features is stated in the Supplementary Tables in To explore whether the eating disorder-related brain regions were associated with obesity, post-hoc correlation analysis between the betweenness centrality values of the networks in the behavioral domain of the identified regions and BMI/WHR was conducted. Twenty-seven identified brain regions were mapped into five behavioral domains which appeared dominantly in the identified regions  and the averaged centrality values of each domain were computed. The results are shown in As a result of SCCA, 16 brain regions and eight questions were selected. The canonical correlation coefficient between two canonical features was 0.8851. The cognition- and reward-related regions showed a large magnitude of loading vectors and the ‘diet’ subscale had the largest magnitude in loading vectors. Thus, high associations between cognition-/reward-related brain regions and diet were observed in the validation. The diet subscale in EAT-26 is not equal to the dietary restraint in TFEQ at the subscale-level but it includes some questions related to dietary restraint and might be partially comparable. In this sense, these results of the validation were largely compatible with those of the discovery set. The list of selected features is stated in the Supplementary Tables in Despite extensive research ,6–10, asIn this current study, we adopted SCCA to identify highly contributable brain regions associated with eating disorders across a wide range of BMI. We found frontoparietal network to be related to restraint eating, supporting the role of this brain region for regulating inhibitory behavior –54. In aOur work adopted eating disorder scores at the question-level rather than the factor-wise scores. We hypothesized that using the full information provided in the question-wise responses (51 features) would be better suited for exploring the link between the brain and eating behaviors than using factor-wise scores (three features) due to the increased information content. Indeed, our previous study investigated the association between functional brain networks and eating behaviors in people with obesity using factor-wise scores and found the association with an effect size  of 0.2422 , which wAlthough we found significant associations between the identified brain regions and dietary restraint scores, no significant association was detected for disinhibition or hunger factors. This should be investigated further, but this inability might be due to the demographic characteristics of enrolled participants, in which obesity-related diseases were excluded. Further validations are required by recruiting participants with aberrant eating disorders.Our study has several limitations. First, we only used betweenness centrality for quantifying complex brain networks. Other graph-related measures such as degree- and eigenvector-centrality, and efficiency might be used to associate the brain and eating behaviors. This is left to future work. Second, obesity is a multifactorial disorder affected by a wide range of factors, including eating behaviors, genetic factors, and other environmental factors ,69. StriHere, we introduced a framework for associating functional brain connectivity and eating disorders at question-level. Harnessing a multivariate association analysis, SCCA, we identified brain regions in executive control and reward system are functionally associated with restraint eating in people with a wide range of BMI. Association between the functional connectivity and WHR suggested the potential role of functional variations in inhibitory control associated with obesity. Our work provides a new perspective on understanding the relationship between eating disorder and brain function.S1 FileThe distribution of obesity-related clinical scores in the discovery set. The list of 51 questions of the TFEQ. The list of selected features as a result of SCCA for the discovery and validation set. The most frequently selected features from bootstrap.(DOCX)Click here for additional data file.


Early reports suggest the fatality rate from COVID-19 varies greatly across countries, but non-random testing and incomplete vital registration systems render it impossible to directly estimate the infection fatality rate (IFR) in many low- and middle-income countries. To fill this gap, we estimate the adjustments required to extrapolate estimates of the IFR from high-income to lower-income regions. Accounting for differences in the distribution of age, sex and relevant comorbidities yields substantial differences in the predicted IFR across 21 world regions, ranging from 0.11% in Western Sub-Saharan Africa to 1.07% for high-income Asia Pacific. However, these predictions must be treated as lower bounds in low- and middle-income countries as they are grounded in fatality rates from countries with advanced health systems. To adjust for health system capacity, we incorporate regional differences in the relative odds of infection fatality from childhood respiratory syncytial virus. This adjustment greatly diminishes but does not entirely erase the demography-based advantage predicted in the lowest income settings, with regional estimates of the predicted COVID-19 IFR ranging from 0.37% in Western Sub-Saharan Africa to 1.45% for Eastern Europe. Given limited testing and vital statistics data, few measures of the COVID-19 infection fatality rate (IFR) exist for developing countries.In Europe and North America, measures of COVID-19 IFRs are known to vary by age, gender and comorbidities.Existing model-based estimates for the developing world have not fully accounted for these factors in predicting IFRs.Using variation in demographics, comorbidities and health system capacity, we predict COVID-19 IFRs for 187 countries, ranging from 0.43% in Western Sub-Saharan Africa to 1.45% in Eastern Europe.Despite lower measured health system capacities, predicted IFRs for most of Sub-Saharan Africa nonetheless remain well below IFRs for high-income countries, while Eastern Europe is predicted to fare particularly poorly.Policy-makers in low-income countries should be cognizant that any demographic advantages with respect to COVID-19 fatality rates are likely to be partially offset by disadvantages in health system capacity.Key policy decisions for COVID-19 containment hinge on its infection fatality rate (IFR). Data from the hardest-hit countries show that the IFR varies by sex, age and certain comorbidities, suggesting a method to extrapolate estimates to new contexts with limited data infrastructure.We understand these predicted IFRs as lower bounds on mortality in low- and middle-income countries, since they are derived implicitly assuming access to advanced healthcare. To account for the likelihood of higher fatality rates in under-resourced health systems, we adjust the predicted IFRs for differences in the relative odds of infection fatality from childhood respiratory syncytial virus (RSV) between world regions as a proxy for local capacity to treat viral respiratory illnesses. This adjustment greatly diminishes, but does not entirely erase, the demography-based advantage predicted in the lowest income settings, with regional estimates of the predicted COVID-19 IFR ranging from 0.43% in Western Sub-Saharan Africa to 1.45% for Eastern Europe.et alet alHere we outline the calculation of our benchmark: the predicted cIFR status, starting from the IFR estimates by age and sex reported in Salje within France by age, sex and comorbidity can be used to predict the variation in IFRs across countries based on their age, sex and comorbidity distributions. To date these are the key factors that have well studied, statistically and clinically significant associations with COVID-19 severity and death. Importantly, we do not require that the underlying distributions of age, sex or comorbidities are similar between France and other countries in our sample; on the contrary, differences across countries in these distributions will drive the variation in predicted IFRs. We now demonstrate our method to extricate from the French age and sex-specific IFRs that part which we claim is portable across contexts: the probability of dying (d) given infection from COVID-19 (I) and the age (a), sex (s), and comorbidity status (c) of patients, that is, The core assumption behind our approach is that variation in the IFR Applying Bayes’ rule, we can recover this cIFR by relating it to the ratio of comorbidity prevalence among COVID-19 fatalities relative to COVID-19 infections  and age and sex-specific IFRs:We now discuss how we measure each of these probabilities.et alet al(1) 10.1136/bmjgh-2020-003094.supp2Supplementary dataet al(2) et al(3) With these ingredients, we can calculate the cIFR assuming healthcare levels similar to high-income countries (HICs) in (1), which we find to be an increasing and non-linear function of both age and comorbidity . To account for this, we adjust our IFR estimates for health-system strength based on a region’s demonstrated capacity to prevent fatalities from viral lung infections. We derive this adjustment from comparative regional hospital case fatality rates for RSV among children aged 0–59 months.We chose this demographic to derive our health system capacity measure because restricting attention to this age bracket approximately purges the RSV IFRs of cross-country variation in the distribution of ages, comorbidities  and sex . With nearly equivalent age, sex and comorbidity rates in this demographic, we take remaining cross-country variation in the IFR for RSV to be attributable principally to health system capacity. We choose RSV acute lower respiratory infection (ALRI) as a proxy for COVID-19 as they are viral lower respiratory infections with overlapping symptoms. Like COVID-19, RSV usually causes mild symptoms, but occasionally develops into a life-threatening illness. As with all viruses, neither is treatable with antibiotics, and, until COVID-19, RSV was unique among the major organisms that cause death from respiratory tract infections to have neither any vaccine nor recognised treatment.et alet al,Normalising the IFR for childhood RSV in HICs to 1, we apply the ratio of these IFRs between regions to scale up our demography-adjusted and comorbidity-adjusted IFR predictions. Unfortunately, we lack country-level IFR estimates. However, Shi Adjusting for health system capacity increases the cIFR in poorer regions by almost an order of magnitude . At agesWith this health system-adjusted cIFR in hand, we recalculate the country-specific IFRs , yielding the highest IFR among the included studies.The results are presented in Note that we lack coverage for LICs in this validation exercise. The lack of representative seroprevalence studies and COVID-19 mortality data to estimate IFRs in such contexts is a key motivation for this study and highlights the need for modelled predictions. For example, we are aware of two serological studies measuring prevalence rates from countries in Sub- Saharan Africa: one based on a representative sample of Nampula, Mozambique,Our results illustrate the possibility of predicting COVID-19 IFRs with a methodology that (1) uses information readily available for most of the world— namely age and comorbidity distributions as well as proxies for health system capacity, (2) relies on parsimonious and transparent assumptions and (3) appears broadly consistent with the limited set of IFRs generated from random COVID-19 testing. Although we produce estimates at national level, subnational variability in distributions of comorbidities, age and sex may be important enough to require IFR estimations at subnational level. A merit of our approach is its portability to any community level where comorbidity, sex and age distributions and health system capacity (compared with France) are known.While our calculations including adjustments for health system strength still suggest somewhat lower IFRs in the least developed economies than in the most advanced economies, our estimates are significantly higher than IFRs used in other recent COVID-19 forecasts for Africa,


Studies on conditional relative survival in primary central nervous system lymphoma (PCNSL) have hitherto been lacking in the literature. Using data from the Netherlands Cancer Registry, we examined the conditional 5-year relative survival up to 5-year postdiagnosis among PCNSL patients in the Netherlands. An encouraging finding of our study was that excess mortality decreased after each additional year survived postdiagnosis. However, on the other side of the pendulum, conditional 5-year relative survival did not exceed 95%. This finding indicates that PCNSL patients continue to experience substantial excess mortality, as compared to age- and sex-matched groups from the general population.2 Despite the encouraging progress, the unfortunate reality remains that a high relapse rate characterizes PCNSL and much of the mortality occurs within the first few years postdiagnosis.1–4 In considering the latter, it is of interest to establish the prognosis after having survived a specified time since diagnosis . Statistics on conditional survival that have been corrected for the life expectancy in the general population are lacking in PCNSL . Therefore, this nationwide, population-based study aimed to examine up-to-date conditional 5-year relative survival estimates among PCNSL patients in the Netherlands.PCNSL is a rare and highly aggressive non-Hodgkin lymphoma restricted to the brain, leptomeninges, spinal cord, and eyes. The population-level survival of PCNSL patients improved significantly over the past decades—mostly due to the increased use of high-dose methotrexate-based chemotherapy—albeit confined to patients up to age 70.1 PCNSL was confirmed by histology, cytology, and/or flow cytometry and defined using International Classification of Diseases for Oncology morphology and topography codes as described elsewhere.1 The Privacy Review Board of the Netherlands Cancer Registry approved the use of anonymous data for this study.We selected all patients diagnosed with PCNSL of the diffuse large B-cell type between 1989 and 2018—with survival follow-up through December 31, 2019—from the Netherlands Cancer Registry, which ascertains all newly diagnosed malignancies in the Netherlands since 1989 through multiple notification sources. Details about the registry are described elsewhere.5 Excess mortality, as compared to the general population, is considered minimal when 5-year relative survival exceeds 95%.6 Differences in survival estimates between subgroups were considered statistically significant when the 95% CIs do not overlap.We calculated 5-year relative survival at diagnosis and the conditional 5-year relative survival for each additional year survived up to 5 years postdiagnosis, conditional on being alive at the beginning of that year. Survival estimates were presented for the overall cohort and stratified by sex and age at diagnosis . Relative survival was calculated to estimate disease-specific survival as the ratio of the patients’ overall survival to the expected survival, based on national population life tables, stratified by age, sex, and calendar year.7 It was applied for patients diagnosed during 1989–2018 who were alive during the follow-up interval 1998–2019. The estimates produced by the hybrid approach herein can be interpreted as the predicted survival probabilities for patients diagnosed during 1998–2019. The manner how the survival data was constructed under the hybrid approach resulted in 10 years of postdiagnostic follow-up information to compute the conditional 5-year relative up to 5 years postdiagnosis. Brief details about the statistical analyses are described in the figure legend.The hybrid approach—which was described and empirically validated by Brenner and Rachet and is conceptually similar to the approach used to estimate the life expectancy at birth—was used to compute up-to-date survival estimates in the setting where incidence data lag behind mortality statistics by left-truncating the survival probabilities at the start of the period of interest, besides right-censoring it at its end.A total of 1,987 PCNSL patients were diagnosed in the Netherlands during 1989–2018 . Five-year relative survival increased sharply from 24% at diagnosis to 47% after 1 year postdiagnosis, and thereafter more gradually (60% at 5 years postdiagnosis; 6 indicating that PCNSL patients, regardless of age, continue to experience substantial excess mortality compared to equivalent groups from the general population. The continuing excess mortality might be explained by disease recurrence, late treatment-related sequelae, and the presence of comorbidity—especially in older patients. The main limitations of the study were the lack of detailed information throughout most of the registry to stratify survival estimates according to well-established prognostic indices and treatment.4 Also, the estimation of the conditional 5-year relative survival beyond 5-years postdiagnosis could not be reliably explored due to the comparatively small numbers of patients at risk after that time point. Nevertheless, this study highlights that future intervention studies in the upfront and salvage setting are needed to improve both the short- and long-term outcomes in PCNSL patients.To our knowledge, this is the first population-based study that examined up-to-date estimates of conditional 5-year relative survival among PCNSL patients. Age-specific information on conditional relative survival—along with information on specific risk factors—can provide PCNSL patients with relevant information regarding survivorship and support physicians to plan more tailored surveillance and follow-up activities. Moreover, this study provides clinically relevant insight into age-specific excess mortality at each additional year survived postdiagnosis that is both encouraging and daunting. Encouraging is the fact that excess mortality decreased over time at each additional year survived postdiagnosis, especially among patients aged 18–50 years at diagnosis. The results are daunting because conditional 5-year relative survival did not exceed 95%,


The relative contributions of calcium and strong binding cross-bridges to thin filament activation were dissected by increasing the concentration of calcium from relaxing (pCa 7.5) to saturating levels (pCa 4.5) before and after incubating the exchanged fibers in the myosin inhibitor para-aminoblebbistatin (AmBleb). At pCa 4.5, the relative contributions of calcium and strong binding cross-bridges to thin filament activation were ≈69 and ≈31%, respectively. Additionally, switching from isometric to isotonic contraction at pCa 4.5 revealed that strong binding cross-bridges contributed ≈29% to thin filament activation . Thus, we showed through two different approaches that lowering the number of strong binding cross-bridges, at saturating calcium, significantly reduced the activation of the thin filament in human slow-twitch fibers. The contribution of myosin to activation resembled that which was previously reported in rat cardiac and rabbit fast-twitch muscle preparations. This method could be applied to slow-twitch human fibers obtained from the soleus muscle of cardiomyopathy patients. Such studies could lead to a better understanding of the effect of point mutations of the cardiac myosin head on the regulation of muscle contraction and could lead to better management by pharmacological approaches.It has been shown that not only calcium but also strong binding myosin heads contribute to thin filament activation in isometrically contracting animal fast-twitch and cardiac muscle preparations. This behavior has not been studied in human muscle fibers or animal slow-twitch fibers. Human slow-twitch fibers are interesting since they contain the same myosin heavy chain isoform as the human heart. To explore myosin-induced activation of the thin filament in isometrically contracting human slow-twitch fibers, the endogenous troponin complex was exchanged for a well-characterized fast-twitch skeletal troponin complex labeled with the fluorescent dye N-((2-(Iodoacetoxy)ethyl)-N-methyl)amino-7-nitrobenz-2-oxa-1,3-diazole (fsTn-IANBD). The exchange was ≈70% complete ( Mammalian muscles are either smooth or striated. Striated muscles are further classified as cardiac, fast-twitch skeletal, and slow-twitch skeletal. Each type of muscle has properties suited to its function. Activation of all striated muscles are triggered by increases in intracellular calcium concentration but the mechanism of regulation and contribution of myosin to activation differs among the muscle types . These dIt is clear in solution studies that myosin is both an enzyme and an activator of the regulatory apparatus of striated muscle . The actActivation of actin thin filaments by myosin heads has also been observed in isometrically contracting skinned fast-twitch muscle fibers. In this preparation, myosin-induced activation was shown at submaximal calcium concentrations after exchanging the endogenous fast-twitch skeletal troponin complex (fsTn) for an fsTn labeled with N-((2-(Iodoacetoxy)ethyl)-N-methyl)amino-7-nitrobenz-2-oxa-1,3-diazole (IANBD) on Cys 133 of troponin I [IANBD-labeled fsTn (fsTn-IANBD)] . Myosin-Cycling cross-bridges also activate cardiac muscle thin filaments at submaximal and saturating calcium levels. For example, lowering “strong” cross-bridge binding with orthovanadate reduced both calcium sensitivity and activation in isometrically contracting rat papillary muscle bundles . Similarex vivo model for studying the disease mechanism in humans  for fsTn-IANBD. Cys 133 is only present in fsTn, and it provides a convenient location for attachment of an environmentally sensitive probe . This laOur results suggest that not only calcium but also strongly bound, cycling cross-bridges contribute to the thin filament activation state of slow-twitch human soleus muscle fibers. Thus, in spite of having a fast-twitch troponin complex as a sensor, our slow-twitch fibers are able to detect the activating effect of the human cardiac myosin heavy chain on the human thin filament during isometric contraction, as previously reported in rat trabecula. The observation of the strong activating effect of cycling cross-bridges on thin filaments in isometrically contracting human slow-twitch fibers has implications in understanding the crosstalk between thin and thick filaments, the development of myosin-based cardiomyopathies, and their therapeutic treatment with small molecules.Purification of the rabbit fsTn consisting of the three fast-twitch rabbit subunits and its labeling with IANBD on Cys 133 of troponin I were accomplished as previously described .Biopsies of the soleus muscle were obtained from healthy adult individuals and stored as for previous studies . Approva+]/M) and were in the range of 7.5 (relaxing solution) to 4.5 (activating solution).The exchange, rigor, pre-rigor, relaxing, and activating solutions were used as described for fast-twitch skeletal muscle . The comi are bound to the active site, formation of the strong actomyosin interaction is inhibited , and IANBD emission intensity was previously described . SL was escribed , 1986.Single-skinned fibers (8–10 mm in length) were attached between the force transducer and a lever system of the apparatus using cyanoacrylate glue . The ends of the fibers were stiffened with glutaraldehyde as previously described . Prior tThe duration of the troponin exchange period was established from a separate set of skinned fibers in which the time response of the troponin exchange was followed using a confocal fluorescence microscopy system coupled to an inverted microscope placed under the mechanical setup as previously described . In shorT-test (p < 0.05) in GraphPad Prism (version 4.02).Force and fluorescence transients were fitted by a mono-exponential function in biokine 32 . The steady state dependence of force and emission intensity of IANBD on calcium concentration was fitted to data from individual fibers using the Hill equation. All obtained parameters were analyzed in GraphPad Prism (version 4.02). All values are given as mean ± SEM with n representing the number of experiments. Mean values were compared using paired Student’s Essential prerequisites for analyzing thin filament regulation in contracting muscle fibers under meaningful conditions are large extent of exchange, specificity of exchange, and preservation of functional and structural viability of the fsTn-IANBD exchanged slow-twitch muscle fibers. These issues were addressed by confocal imaging, PAGE-Western blot analysis, and characterization of mechanical properties.z-axis direction. Therefore, we incubated the fibers for 3.5 h in 0.5 mg/mL fsTn-IANBD before doing mechanical experiments. The striated pattern of emission observed in the The spatial and temporal course of the equilibration of fsTn-IANBD within the cross-section of a fiber is shown in n = 8) of fast skeletal troponin I subunit (fsTnI). The presence of fsTnI in slow-twitch muscle fibers confirms the effective exchange of fsTn-IANBD. This amount of exchange was similar to previous reports . Maximum force (pCa 4.5) was slightly reduced by troponin exchange and thereafter . This value was reduced to 3.21 ± 0.23 s–1 (n = 8) after the troponin exchange, and to 2.79 ± 0.15 s–1 (n = 8) after completing the first part of the experiment : at pCa 4.5, mean ktr and mean rate constant of fluorescence decrease are 3.21 ± 0.23 s–1 (n = 8) and 3.93 ± 0.24 s–1 (n = 8), respectively. These interpretations of the fluorescence signals during the isotonic and isometric phases are consistent with other reports  steady state force generation and steady state IANBD emission intensity during isometric contraction, (2) dynamic changes in IANBD emission intensity and force upon switching from isometric conditions (high load) to isotonic shortening at very low loads (≈5% of isometric force), and (3) the corresponding dynamic changes upon re-stretching the fiber to the original fiber length and filament overlap . Changes reports .Since we wanted to separate the effects of calcium activation from activating effects of force producing myosin binding to the thin filament, we used AmBleb to inhibit myosin heads from entering the strong binding, force-generating states. We determined in a separate group of muscle fibers, the AmBleb concentration required to effectively prevent the formation of the strong binding states, as determined by its inhibition of force development . Knowing50) of force development, AmBleb treatment significantly modified neither this variable nor its cooperativity (nH). Similarly, AmBleb treatment modified neither calcium sensitivity nor cooperativity of thin filament activation as measured by fsTn-IANBD emission intensity  of the amplitude of the fluorescence increase, induced by switching from high load to low load  the myosin inhibitor AmBleb and (2) suddenly switching from isometric contraction to isotonic shortening at low loads. In contrast to previous reports using the same probe for fast-twitch rabbit psoas muscle fibers, here in slow-twitch soleus fibers, saturating calcium concentration alone did not fully activate the thin filament, and the amount of myosin-induced activation increased with the activation level.We introduced a fluorescent probe on Cys 133 of the exchanged fsTn-IANBD as we did in other muscle preparations . In fsTnIncubating the fibers in AmBleb produced a 31% decrease in the fluorescence signal associated with regulatory conformational changes at maximal activation . That obThe mechanical maneuver of suddenly switching from isometric contraction to isotonic shortening, i.e., MU, has been previously used in studies on fast-twitch skeletal muscle fibers to decrease the population of strong binding states of cycling cross-bridges and their contribution to thin filament activation . In thosAltogether, it seems to apply that in human slow-twitch muscle fibers, the magnitude of myosin-induced thin filament activation detected by means of myosin inhibitors is similar to that previously reported for fast-twitch and cardiac animal tissues. In contrast, decreasing the occupation of myosin strong binding states by MU at saturating calcium induces a higher degree of inactivation of the thin filament in human slow-twitch than in rabbit fast-twitch fibers, especially when the same probe was used . These dFinally, we noted that the somewhat smaller amplitude of fluorescence change induced by MU (29%), in comparison with chemical inhibition (31%), is also observable in the report of kobs of thin filament inactivation induced by MU increased from ≈10 to ≈150 s–1 with increasing calcium concentrations. These values are close to those obtained for the kobs of the slow phase of the biphasic fluorescence change observed in rabbit psoas myofibrils containing the same probe by rapid mixing with calcium containing buffers , nor those of force decay following calcium removal  is much faster than force redevelopment (ktr), which fits with previous reports using the same  the slow-twitch fibers used, (b) the human tissue, (c) the nature of the hybrid system in our experiments, (d) the fsTn-IANBD probe, and (e) a combination of all or some of these. These possibilities should be the subject of detailed, systematic analysis in the future since they have important implications for regulation of muscle contraction. It is especially interesting that in our hands, even after exchanging rabbit fsTn for a human fsTn , in rabbit psoas fast-twitch fibers, we see a significantly decreased pCa50 of force development after incubation in 50 μM AmBleb (unpublished results). This opens the possibility that the conserved pCa50 value of force development after AmBleb treatment reported here could be indeed a feature of slow-twitch muscle. To explore this question, pCa–force relationships should be recorded at several AmBleb concentrations. This procedure would allow analyzing the changes of the pCa50 values of force development at progressive levels of force inhibition, since in our experiment the effect could be masked by the profound force inhibition that was achieved.Treatment with myosin inhibitors that stabilize the ADP. Pelopment  and thinelopment . The conOur hybrid system incorporating an fsTn into a slow-twitch skeletal muscle fiber might not completely resemble the activation and inactivation kinetics of the native ssTn troponin complex in slow-twitch muscle. However, the well-known characterization of the steady state and dynamic behavior, including the previously shown sensitivity of the label to the myosin activating effect of fsTn-IANBD incorporated in fast-twitch skeletal muscle , makes iThe chemical and mechanical approaches used here to reduce the occupation of the strong binding states of the myosin head have been shown to trigger changes in the thick filament itself, such that the observed thin filament inactivation induced by those protocols could be explained by alternative mechanisms rather than by a direct effect of strong binding myosin on actin and tropomyosin. These facts, however, do not exclude the interpretation that actin bound myosin heads contribute to activation of the thin filament during steady state calcium activation, which is considered a fundamental property of thin filament regulation. For a comprehensive review, see Here we show by two different approaches, that at submaximal and maximal calcium concentrations, strong binding states of cycling cross-bridges significantly contribute to thin filament activation in human slow-twitch muscle fibers. To the best of our knowledge, this is the first study exploring this issue in slow-twitch skeletal muscle, which completes the view that myosin-induced activation is a conserved phenomenon in striated muscle, including human tissue.Human cardiac myosin mutations are conserved in slow-twitch fibers of the human soleus muscle and are accessible in human patients . ApplyinThe raw data supporting the conclusions of this article will be made available by the authors, without undue reservation, to any qualified researcher.The studies involving human participants were reviewed and approved by the Hannover Medical School Ethics Committee (Vote No. 2729/2001). The patients/participants provided their written informed consent to participate in this study.This project was the original idea of BB. He created the original concept (including SL correction of fluorescence transients), designed the experiment, and established the experimental setup. AL-D contributed to establish the experiment design, performed mechanical and fluorescence experiments, analyzed the data, and wrote the manuscript. JC created the original concept, contributed to data interpretation, and edited the manuscript. RS contributed to data interpretation, supervised the project, and contributed to writing the manuscript. SZ isolated and labeled fsTn-IANBD and contributed to Western blot experiments. BP performed Western blot experiments. FM isolated single slow-twitch human fibers from soleus muscle biopsies. AM-C and AR developed AmBleb, contributed to data interpretation, and edited the manuscript. TK supervised the project and edited the manuscript.AM-C is the owner of Optopharma Ltd. and AR is part-time employed by Optopharma Ltd. Related patents: PCT/EP2017/051829, WO2017129782. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Attaining the goal of reducing the global malaria burden is threatened by recent setbacks in maintaining the effectiveness of vector control interventions partly due to the emergence of pyrethroid resistant vectors. One potential strategy to address these setbacks could be combining indoor residual spraying (IRS) with non-pyrethroids and standard insecticide-treated nets (ITNs). This study aimed to provide evidence on the incremental epidemiological benefit of using third-generation IRS product in a highly endemic area with high ITN ownership.A cluster-randomized, open-label, parallel-arms, superiority trial was conducted in the Mopeia district in Zambezia, Mozambique from 2016 to 2018. The district had received mass distribution of alphacypermethrin ITNs two years before the trial and again mid-way. 86 clusters were defined, stratified and randomized to receive or not receive IRS with pirimiphos-methyl (Actellic®300 CS). Efficacy of adding IRS was assessed through malaria incidence in a cohort of children under five followed prospectively for two years, enhanced passive surveillance at health facilities and by community health workers, and yearly cross-sectional surveys at the peak of the transmission season.A total of 1536 children were enrolled in the cohort. Children in the IRS arm experienced 4,801 cases  versus 5,758 cases in the no-IRS arm , resulting in a crude risk reduction of 18% and an incidence risk ratio of 0.82 . Facility and community passive surveillance showed a malaria incidence of 278 per 10,000 person-month in the IRS group  versus 358 (95% CI 355–360) per 10,000 person-month at risk in the no-IRS group , resulting in an incidence rate ratio of 0.65 . In the 2018 survey, prevalence in children under five in the IRS arm was significantly lower than in the no-IRS arm .In a highly endemic area with high ITN access and emerging pyrethroid resistance, adding IRS with pirimiphos-methyl resulted in significant additional protection for children under five years of age.https://clinicaltrials.gov/ct2/show/NCT02910934?term=NCT02910934&draw=2&rank=1.Trial registration: ClinicalTrials.gov identifier NCT02910934, registered 22 September 2016,  There has been remarkable success in the global fight against malaria since 2000. During the period 2000–2015, coordinated malaria control efforts helped reduce worldwide malaria mortality rates in all ages by 47%, averting an estimated 4.3 million malaria deaths  mosquitoes per trap-night vs. 2.5 [1.8–3.4] mosquitoes per trap-night) [A full analysis of the entomological impact of the IRS campaigns will be presented in a complementary manuscript . In term/ 2,309) –43. Sampbiensis) . Baselinsted 336/1 being Ap-night) .An. gambiae s.l. populations from the nearby districts of Mocuba  and Morrumbala  [An. gambiae s.l. was 100% susceptible to both alphacypermethrin and to PM. Anopheles funestus s.l. from Mopeia were tested in 2018 and were 100% susceptible to PM and DDT, but showed signs of emerging resistance to alphacypermethrin , deltamethrin , and bendiocarb  [The WHO tube test results from 2015 showed that pyrethroid resistance was evident in lothrin) , althougrtality) , 43.The IRS campaigns of 2016 and 2017 made positive contributions to malaria control in this high transmission district of Mozambique, as evident by: (1) reduced infection incidence in IRS clusters relative to no-IRS clusters, even in the presence of high ITN ownership; (2) reduced confirmed clinical case incidence at public health clinics; and among those detected by community health workers, and (3) reduced odds of malaria infection in the population under five years of age during the 2018 prevalence survey.Malaria policy makers and implementers face difficult decisions regarding the best available tools and their optimal deployment. Prior cluster-randomized trials have provided differing results, suggesting that the added value of the combination of ITNs and IRS is variable and likely.dependent on local factors like transmission intensity, vector bionomics, insecticide resistance profiles, and implementation strategy –27.This study generated robust evidence to help support those making policy and implementation decisions about the use of IRS with a non-pyrethroid insecticide in communities with high rates of malaria transmission, high ITN ownership of standard pyrethroid-only ITNs, and evidence of emerging pyrethroid resistance in the local vector populations.P. falciparum infections detected in the incidence cohort, and around 28% protective efficacy when considering confirmed cases reporting to the public health system for treatment. These suggest that when resources are available, combining these two interventions will reduce malaria incidence. Some of the reasons contributing to this incremental impact include the indoor insecticide-mosaic created by combining pyrethroid ITNs and organophosphate IRS and the benefit obtained at the household level from at least one insecticide present independently of compliance with ITN use. The adjusted analysis performed with the active cohort data confirmed that the interaction of IRS and ITNs leads to the greater incidence reduction, namely 38%. While this study provides valuable evidence on the combination of interventions, it also highlights the need to generate evidence on the value of IRS in combination with ITNs with piperonyl butoxide and non-pyrethroid ITNs to inform programmatic decision-making.This study found significant added malaria protection by adding IRS with PM to a policy of universal coverage with a pyrethroid-only ITN in Mopeia. This was quantified as 18% protective efficacy when considering new The reduced odds ratio of malaria infection observed in the population under five years of age during the 2018 prevalence survey is particularly interesting as it aligns with the protective effect of IRS also observed in the active and passive surveillance components of the study. In IRS clusters, under-five prevalence was held relatively stable from 2017 (50%) to 2018 (47%), while in no-IRS clusters under-five prevalence increased from 47 to 62%. This apparent increase in under-five prevalence in no-IRS clusters occurred in conjunction with (1) the mass ITN distribution campaign of 2017 that improved ITN access to more than 90% and (2) even as prevalence in the over-five population fell from 40 to 25% during the same time. Additionally, the combination of IRS and ITNs appeared to significantly reduce the odds of malaria infection in the under-five population by almost 50% during the five months after the second spray campaign and following the mass distribution campaign. These interesting trends highlight how complex the relationship between malaria infection incidence, malaria clinical case incidence, and malaria infection prevalence can be, particularly in very highly endemic areas with year-round transmission.These results are in contrast from those of previous cluster-randomized trials conducted in lower transmission settings in which no benefit with a combined IRS and ITN approach showed no added benefit , 24, 27,This study employed a robust cluster-randomized design, with a multiplicity of outcome measures, a large sample size, and close community engagement, but there are some important limitations. Children in the active cohort were subject to screen and treatment every visit, resulting in early detection of infections followed by prompt treatment, which also provided temporary prophylaxis. Given that malaria infections were more common in children in the no-IRS arm, they received proportionally more treatments  which may have reduced the difference between arms, resulting in an underestimation of the true added benefit of the combined approach as adjustments done at analysis cannot fully correct for this prophylaxis. Additionally, the net reduction in malaria incidence was lower than originally expected for sample size calculations; this was, however, partly compensated by the coefficient of variation, which, once retrospectively calculated from empirical data, was lower than assumed.Another potential source of bias could be false-positive RDT results. The RDTs used are based on the HRP2 antigen, which can persist for several weeks after treatment potentially inflating estimates of incidence in the active cohort and adding uncertainty around the number of true infections . This efAn. funestus s.s., shows moderate levels of pyrethroid resistance. The cost-effectiveness of this combined approach has been analysed in the context of this trial resulting in a separate manuscript.Malaria remains a challenge that will require multiple preventive as well as therapeutic intervention strategies, and many of these tools will need to be used in combination to maximize impact and reach elimination goals. Understanding when and where to combine vector control strategies requires locally relevant data to ensure that resources are invested wisely, particularly in the context of the “High burden for high impact” strategy. This study demonstrated added value for IRS with a non-pyrethroid active ingredient in the context of high coverage with standard (pyrethroid-only) ITNs, as well as good access to malaria case management commodities. This supports consideration of co-investment strategy (IRS and ITNs) in areas such as Zambezia, where transmission is high and the local primary vector species, In 2017, Mozambique had 5% of the global share of malaria cases . The resAdditional file 1: Table S1. Factors potentially associated with a positive RDT at baseline by spray status. Figure S1. Reported net ownership in both groups throughout the trial. Figure S2. Cohort incidence by spray status correcting for a potential RDT residual positivity of 30 days. Table S2. Adjusted incidence using a multi-variable generalized estimating equation model using only data after the mass ITN distribution campaign. Table S3. Univariate analysis of covariables and their association with RDT-positive status at monthly follow-up at health facility. n= number of observations.


Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been initially defined as a disease of the respiratory tract; however, with the increasing number of patients and announcing that the virus became a pandemic, new systemic clinical manifestations are observed, including dermatological manifestations. However, the identification and characteristics of these manifestations are still controversial. This review article aims to evaluate the medical literature and explore the dermatological clinical manifestations in patients with SARS-CoV-2. The literature was reviewed through MEDLINE®, Ovid, PubMed®, and Embase®. Searching terms included were a combination of "dermatological" OR "skin" AND "symptoms" OR "manifestations" AND "SARS-CoV-2". The following step was filtering the results to include only original research studies investigating the different types of skin and dermatological clinical manifestations in patients with SARS-CoV-2. A total of 879 studies were retrieved. Following the exclusion of studies on animals and including only studies on humans, 32 studies emerged. Altogether, seven studies were identified as eligible, covering 555 patients with SARS-CoV-2 who had dermatological symptoms. Three studies were retrospective, two studies were prospective, and two studies were case series. Different types of dermatological lesions can occur in patients with SARS-CoV-2, most commonly erythema, urticaria, and varicella-like rash. Dermatological manifestations with SARS-CoV-2 can be misdiagnosed with other conditions. Further studies with robust design are needed. Coronaviruses are defined as a class of viruses that commonly lead to mild to moderate respiratory tract infections . MoreoveSARS-CoV-2 virus has been primarily identified in Wuhan city in China, in November 2019 . The traSigns and symptoms of the new viral infection might range from an absence of symptoms to severe and sometimes, life-threatening condition . At the One of these systemic symptoms is dermatological manifestations . Some paOur review aims to examine the current medical literature to explore the different types of dermatological clinical manifestations in patients with SARS-CoV-2. Methodology and search strategyThis systematic review of the literature was performed in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist recommendations for systematic review and meta-analysis . This sySearching terms included "dermatological" OR "skin" AND "symptoms" OR "manifestations" AND "SARS-CoV-2". All the titles, as well as abstracts that emerged from this exploration, were reviewed completely to prevent missing any eligible studies. The results were then filtered to include only original research studies examining the different types of skin and dermatological clinical manifestations in patients with SARS-CoV-2. Additionally, all study designs from different countries were included. Only studies written in the English language were listed as related studies, which can be further assessed in the second step. Eligibility criteriaFollowing this stage, the inclusion criteria to choose the studies that will be recognized in the systematic review were determined. Abstracts were reviewed manually to determine the appropriate abstracts to be considered. The inclusion criteria included discussing enough data on the dermatological symptoms with SARS-CoV-2. Moreover, only studies done among adult patients were included. Furthermore, references of the chosen studies were assessed to distinguish any related studies. Lastly, the required data sets were collected from the final record of eligible studies and summarized. Studies were eliminated in case of in vitro or animal involvement, overlapped or incomplete data, and unavailability of full-text studies or inappropriate study design. Entire details on the search strategy are shown in Figure Data review and analysisThe first step included a preparatory review, a specially designed excel sheet was used for data extraction. Chosen data from eligible studies were then reviewed through the excel sheet. Any studies published by one research group examining alike variables were evaluated for any potential duplication. Cochrane, a quality assessment tool, was used to evaluate the quality of the included clinical studies . Data weResultsAfter searching the abstracts and reviewing the eligibility criteria in identified potential abstracts, a total of seven studies -20 were Additionally, All the included studies considered the objective of describing the dermatological manifestations of patients with SARS-CoV-2 with varying severity levels in different countries. Due to the scarcity of data and lack of experience with the newly identified virus, all study designs were included -20.Furthermore, all the studies identified the types of dermatological manifestations in patients. Erythema and urticaria were common in four studies , 17- 19,DiscussionThe novel SARS-CoV-2 virus was identified in late 2019, with minimal knowledge and experience regarding its diagnosis and treatment until present . AlthougThe present review evaluated the description and characters of dermatological manifestations in patients with SARS-CoV-2. It has been shown that different types of cutaneous lesions occur in patients with SARS-CoV-2, even in patients with mild respiratory symptoms. Hence, the misdiagnosis of dermatological lesions in SARS-CoV-2 is common.Furthermore, the most frequent types of lesions were varicella-like rash and rash resembling recent viral infection, in addition to urticaria and erythema. It is worth noting that these lesions might be itching or non-itching and are usually mildly severe in most patients, resolving at the end of the course of infection. Dermatological lesions can also develop at a later stage of the infection.Erythema and urticaria in SARS-CoV-2 patients have been described in some studies. The most robust study design described dermatological manifestations in 375 Spanish SARS-CoV-2 patients. The study described the lesions as commonly occurring in the acral areas, with 19% having erythema in the form of pseudo-chilblain, which developed in later stages in the infection, and another 19% having urticaria lesions. Also, the dermatological lesions related to SARS-CoV-2 were severe in the acral area, with less severe lesions in other parts. Additionally, the maculopapular rash was also characteristic in Spanish patients with a prevalence of 47% .Another study that had a retrospective design reviewed 14 patients and showed that dermatological lesions appeared at a later stage of the infection, with inflammatory lesions occurring in 50% of patients in the form of exanthema, chickenpox-like vesicles. Additionally, the study identified that the remaining 50% of patients had vascular lesions in the form of porcelain-like macules, livedo, necrotic purpura, chilblain, and eruptive cherry angioma .Another study from Italy included 88 patients in a retrospective design and demonstrated that 20.4% of patients had cutaneous manifestations, with eight patients developed the dermatological symptoms at an earlier stage of the onset of the SARS-CoV-2 infection, while ten patients developed the lesions after hospitalization due to SARS-CoV-2 due to severe infection. Importantly, there was no correlation between the occurrence of dermatological lesions and the severity of SARS-CoV-2 infection, where some patients had dermatological lesions without developing respiratory symptoms for SARS-CoV-2. The study also highlighted that the lesions are resembling those occurring in common viral infections . This fiIt is worth to mention that other frequent conditions can misdiagnose dermatological lesions occurring in patients with SARS-CoV-2. In Thailand, one study described one out of 48 SARS-CoV-2 patients who had a rash with petechiae that was misdiagnosed with dengue disease, especially with the absence of routine biopsy in this setting .The included studies also had some limitations; most of the included studies were performed in one center, which may affect the external validity of outcomes. Also, the sample size in each study was relatively small, which could reduce the reliability of their outcomes. These limitations should be considered in future studies.Finally, this is considered the first systematic review to identify the dermatological manifestations occurring in patients with the novel SARS-CoV-2 infection. This should be a guide for clinicians to prevent the misdiagnosis of these manifestations with other dermatological conditions.Dermatological lesions are frequent in patients with SARS-CoV-2, especially erythema, urticaria, and varicella-like rash. Differential diagnosis should be thoroughly considered before deciding that the present rash is related to SARS-CoV-2 infections. Till present, the rash is not correlated to the severity of SARS-CoV-2 infection, which needs to be confirmed with studies with more robust design and larger sample sizes. These findings should be considered by clinicians working with patients with SARS-CoV-2 in order not to misdiagnose the occurrence of dermatological lesions, which may delay therapy or increase the risk of complications.