Vascular cognitive impairment (VCI) is a heterogeneous entity with multiple aetiologies, all linked to underlying vascular disease. Among these, VCI related to subcortical small vessel disease (SSVD) is emerging as a major homogeneous subtype. Its progressive course raises the need for biomarker identification and/or development for adequate therapeutic interventions to be tested. In order to shed light in the current status on biochemical markers for VCI-SSVD, experts in field reviewed the recent evidence and literature data.The group conducted a comprehensive search on Medline, PubMed and Embase databases for studies published until 15.01.2017. The proposal on current status of biochemical markers in VCI-SSVD was reviewed by all co-authors and the draft was repeatedly circulated and discussed before it was finalized.This review identifies a large number of biochemical markers derived from CSF and blood. There is a considerable overlap of VCI-SSVD clinical symptoms with those of Alzheimer’s disease (AD). Although most of the published studies are small and their findings remain to be replicated in larger cohorts, several biomarkers have shown promise in separating VCI-SSVD from AD. These promising biomarkers are closely linked to underlying SSVD pathophysiology, namely disruption of blood-CSF and blood–brain barriers (BCB-BBB) and breakdown of white matter myelinated fibres and extracellular matrix, as well as blood and brain inflammation. The leading biomarker candidates are: elevated CSF/blood albumin ratio, which reflects BCB/BBB disruption; altered CSF matrix metalloproteinases, reflecting extracellular matrix breakdown; CSF neurofilment as a marker of axonal damage, and possibly blood inflammatory cytokines and adhesion molecules. The suggested SSVD biomarker deviations contrasts the characteristic CSF profile in AD, i.e. depletion of amyloid beta peptide and increased phosphorylated and total tau.Combining SSVD and AD biomarkers may provide a powerful tool to identify with greater precision appropriate patients for clinical trials of more homogeneous dementia populations. Thereby, biomarkers might promote therapeutic progress not only in VCI-SSVD, but also in AD. There are not yet efficient ways of treating or preventing dementia disorders of which Alzheimer’s disease (AD) remains the most common target for therapeutic interventions. In contrast, only few clinical pharmacological trials have been conducted in subjects with vascular cognitive impairment (VCI). The lack of treatment success in VCI may be largely due to the heterogeneity of cerebrovascular diseases, with the majority of VCI clinical trials being performed in stroke patients. Only few clinical trials have been performed in patients with subcortical small vessel disease (SSVD), a common, fairly homogeneous, but often under-recognized type of VCI (VCI-SSVD) –4. The cA focused meeting on VCI-SSVD biochemical markers was held as a part of the 9th International Congress on Vascular Dementia in Ljubljana, Slovenia, on 18 October, 2015. Experts in this field reviewed the current evidence and literature data. For the purpose of this narrative review, we conducted a comprehensive search on Medline, PubMed and Embase databases for studies published until 15.01.2017. The key words used in the current search were: subcortical small vessel disease, vascular dementia, vascular cognitive impairment, Alzheimer’s disease, Binswanger’s disease, biomarker(s), cerebrospinal fluid, blood, serum, plasma, blood brain barrier, white matter, genetics, tau protein(s), amyloid, inflammation. We critically reviewed all abstracts and obtained the full text of relevant papers. We grouped the identified relevant subcortical small vessel disease biomarkers into themes and report the major relevant findings. The proposal on current status of biochemical markers in VCI-SSVD was reviewed by the group, including additional experts who did not attend the meeting. The draft was repeatedly circulated and discussed before it was finalized.Cerebral SSVD refers to pathological processes affecting a spectrum of subcortical vascular changes visible on Computed Tomography/Magnetic Resonance Imaging (CT/MRI) as white matter lesions (WML), lacunes and cerebral microbleeds. Underlying vascular pathologies are arteriolosclerosis, lipohyalinosis, fibroid necrosis, oedema and damage to the blood-cerebrospinal fluid and blood–brain barriers (BCB/BBB), the latter resulting in chronic leakage of fluid and macromolecules in the white matter and inflammation  . AlthougClinico-pathological studies have associated the characteristic clinical symptoms of VCI-SSVD  with the bidirectional disruption of pathways connecting the prefrontal cortex with the basal ganglia and thalamus . As oppoAlthough several studies using biochemical markers have been completed and reviewed in AD, such information is still lacking for VCI-SSVD. Here we review studies using a broad range of biochemical markers from cerebrospinal fluid (CSF), plasma or serum in VCI-SSVD. Our primary question is whether they are useful to identify VCI-SSVD. We also review whether there are overlapping and differentiating findings between VCI-SSVD and AD.The BCB/BBB are highly selective permeability barriers that separate the circulating blood from the brain. The function and structure of BCB/BBB alter with aging. Disruption of BCB/BBB function, followed by blood-to-brain extravasation of circulating neuroinflammatory molecules, may increase the risk of brain injury. This may be an important factor for disease progression in both VCI and AD , and incSeveral lines of evidence suggested that the astrocytic protein S100β is a potentially useful peripheral marker of BCB/BBB permeability . S100β cBoth the innate immune system and systematic inflammation have central roles in the pathophysiology of cognitive impairment , 44. WhiC reactive protein (CRP), a biomarker of systemic inflammation, is perhaps the most extensively studied circulatory biomarker of cerebral SSVD pathology. Although its association with SSVD (particularly in the presence of WML) is inconclusive [nclusive –48, sevenclusive , 50. In nclusive , 52, whenclusive .Interleukins (ILs) are a group of cytokines participating in the regulation of the immune response. A classification that proves useful in clinical practice  divides immunological cytokines into type 1 , that enhances cellular immune responses and type 2 , which controls antibody responses. In the vasculature, interleukin-6 (IL-6) is secreted as a pro-inflammatory cytokine by tunica muscularis cells of the blood vessels. As a response to IL-6, the liver synthesizes the CRP. Although the majority of studies reported a positive association [ociation , the useociation . In contociation , 56.α1-antichymotrypsin, an acute phase inflammatory protein, was also increased in individuals with VCI-SSVD compared to healthy controls as well as in prodromal VCI-SSVD patients who later progressed to dementia, whereas in AD it was elevated only in manifest dementia [CSF dementia . Interesdementia .YKL-40, a marker of glial activation, was elevated in CSF of patients with prodromal VCI but not prodromal AD [romal AD .Matrix metalloproteinases (MMPs) are a large family of enzymes active in the extracellular matrix, at the cell surface and intracellularly. Although there are 26 family members, MMP-2, −3, −7, −9, −10 and −12 are mainly active in the brain. Some MMPs, i.e. MMP-2, are constitutively produced and are normally present in the CSF. Others (mainly MMP-3 and MMP-9) are inducible with very low levels in the CSF until an inflammatory response is elicited , 61. ChaNeurofilaments (NFs) are major structural proteins of neurons. They consist of three subunits of low (NF-L), medium (NF-M), or high (NF-H) molecular weight with varying degrees of phosphorylation . NFs mayIn acute cerebral infarction, very high NF-L levels were reported . The CSFIncreased WML load and ventricular dilation were related to increased CSF levels of TIMP-1 and NF-L and to decreased sAPPβ (a marker of amyloid pathology), suggesting that these molecules may function as biological markers of white matter damage .Far less is known about CSF levels of the other NF isoforms. One study reported increased CSF levels of phosphorylated NF-H/M in AD compared with VCI and controls . Others Myelin basic protein (MBP) is a major structural constituent of the myelin sheath . Its funCSF sulfatide is an acidic glycophospholipid of oligodendrocyte-produced myelin sheaths considered as a marker of white matter degradation. It was found to be 200% higher in patients with VCI-SSVD compared to controls and patients with AD , while CFurthermore, this marker was lower in mild cognitive impairment and mild AD compared to control subjects . In anotresearch guidelines for diagnosing incipient and manifest AD [Tau protein is the major component of intracellularly located neurofibrillary tangles and, in the neurofibrillary pathology, it is present in a hyperphosphorylated form. Both total and hyperphosphorylated tau have been found to be increased in the CSF of patients with AD . Total tifest AD , 93.In VCI, CSF T-tau levels have been reported to be either normal –96, incrBeta-amyloid peptides with 40 (Aβ40) and, especially, with 42 amino acids (Aβ42) are the major components of extracellular AD amyloid plaques. Aβ42 is considered to inversely reflect amyloid pathology, having high sensitivity and specificity (>85%) as compared to cognitively intact old subjects and is now recognized as one of the three clinically useful CSF biomarkers (the other two being T-tau and P-tau) for AD , 91. RedSoluble amyloid precursor protein β peptide (sAPPβ) is a product of APP cleavage with potential neurotrophic properties on axons . CSF sAPSeveral plasma markers of coagulation/fibrinolysis have been associated with VCI-SSVD . The cloFibrinogen is the endpoint plasma protein of the clotting cascade. Conflicting results have been published regarding its possible significance as a biomarker in VCI-SSVD [VCI-SSVD –122.Factor VII  has been found increased [antithrombin III, a plasma protein that inactivates thrombin, and D-dimer, a fibrin degradation product, were found to be reduced in VCI-SSVD [ncreased , whereasVCI-SSVD , 124.von Willebrand factor (vWF) [thrombomodulin (CD141 or BDCA-3); the monokine induced by γ-interferon (MIG) or chemokine (C-X-C motif) ligand 9 (CXCL-9) [soluble intercellular adhesion molecule-1 ; soluble vascular cell adhesion molecule-1 (sVCAM-1); and soluble E-selectin (sE-selectin), the two latter mediating the adhesion of white cells (except neutrophils) to the vascular endothelium [Many studies report that numerous proteins expressed by the endothelial cells are positively associated with lacunar infarcts or WML and thus increased in VCI-SSVD because of endothelial damage , 125–128or (vWF) ; thrombo(CXCL-9) ; solubleothelium –133. Howothelium , 135. Spothelium . Thus, tothelium .Homocysteine (Hcy) is the metabolic product of dietary methionine. Hcy is also synthesized in the liver and kidney. Increased total Hcy plasma levels is associated with risk, clinical deterioration and severity of WML in symptomatic patients with SSVD [ith SSVD , 139. Stith SSVD . As receith SSVD . Still wB-type natriuretic peptide  is a polypeptide secreted by heart ventricles in response to excessive stretching of cardiomyocytes. Similarly, cardiac troponin T is a very sensitive and specific indicator of myocardial damage. A few studies report that serum levels of BNP [s of BNP , 142 or s of BNP  are elevmyeloperoxidase in participants with greater WML volumes and silent brain infarcts [Asymmetric dimethylarginine (ADMA) is a key chemical involved in normal endothelial function and thus cardiovascular health. Higher plasma ADMA levels were associated with an increased prevalence of silent brain infarcts after adjustment for traditional stroke risk factors, indicating its potential usefulness as a new biomarker of subclinical vascular brain injury [Clinical studies on markers of oxidative stress in patients with VCI-SSVD and cognitive impairment are scarce. The Framingham study reported lower plasma levels of infarcts . Asymmetn injury . Patientn injury .Hitherto, there are no yet established biochemical markers for VCI-SSVD, although there are potential candidates. For AD, CSF T-tau, P-tau and Aβ42 have been included in the diagnostic criteria by the National Institute on Aging and the Alzheimer’s Association workgroup for all phases of AD, published in 2011 . By analOther promising biomarkers are those reflecting damage to the white matter, such as CSF NF-L and MBP. Both markers correlate with SSVD, but they have also been found to be elevated in AD. This overlap possibly reflects concomitant AD and SSVD pathology. However, both CSF NF-L and MBP can be of value in detecting damage to white matter in patients with VCI-SSVD or MD regardless of the white matter etiology. Markers, such as sulfatide, sAPPβ, MMP-2, MMP-3, MMP-9 and TIMP-1, also hold potential for VCI-SSVD biomarkers, though some of them  have also been described to be altered in AD , 150. OtAt present, combination of markers reflecting SSVD with markers that seem to be more specific for AD pathology such as Aβ42, T-tau and especially P-tau, appears promising for the exclusion of pure AD or favoring the diagnosis of MD .Thus far, biochemical markers with potential benefit for the diagnosis of VCI-SSVD have limited use in every day clinical practice  diagnosis of VCI-SSVD. They can also be used for identifying patients with preclinical SSVD from apparently healthy controls. Furthermore, they have a potential to define a spectrum disorder with pure subcortical vascular disease (i.e. Binswanger’s disease) at one end of the spectrum and pure AD at the other. In between will be the large group of MD patients that will remain a major diagnostic challenge.This review of all biological markers studied in patients with VCI-SSVD identified several fluid biomarkers with evidence for use in diagnostic settings, while others are too early to be considered as potential SSVD biomarkers. There is little value of blood tests at this time since none of the above biomarkers have been adequately studied, whereas CSF helps to separate vascular and neurodegenerative causes based on the presence of BCB/BBB disruption and extracellular matrix breakdown. Obviously, many of the CSF reports cited in this review are based on small series of cases. Replication studies should be done to ensure the reproducibility of the results and calculation of positive and negative predictive values should be provided. At present, it is unlikely that single markers may be sufficient for diagnostic and differentiating purposes. Instead, a combination of biochemical and imaging markers as well as psychometrics will be necessary to improve the diagnostic accuracy.A third potential use of fluid biomarkers is their application as surrogates for disease progression e.g. in clinical pharmacological trials. For that purpose, such biomarkers could be used if different levels of the biomarkers can reflect patients’ clinical severity or extent of WML. If a biomarker fulfills this definition, it could be very valuable in clinical trials obviating the need for repeated expensive MRI examinations.A fourth potential use of fluid biomarkers is to clarify the pathogenesis of the disorder, for example to verify an inflammatory underlying process, perhaps in a subgroup of patients, thus suggesting a (novel) target for therapy. Clearly, much further work needs to be done along these lines.The search for an optimal panel of biomarkers with high sensitivity and specificity through a collaborative international network of biobanks, multi-center collections based on large patient cohorts, combined with population genetics, clinical trials and harmonized protocols and procedures will provide the crucial tools needed to enhance the likelihood of success in identifying valid biomarkers in VCI-SSVD . In addi


Associations between androgens and depressive symptoms were mostly reported from cross-sectional and patient-based studies.sex-specific associations of baseline total and free testosterone, androstenedione and sex hormone-binding globulin with incident depressive symptoms and cognitive status at 5- and 10-year follow-up.Longitudinal data from 4,110 participants of the Study of Health in Pomerania were used to assess Despite sex-specific differences in depressive symptoms prevalence at baseline , cross-sectional analyses showed no associations between sex hormones and depressive symptoms. In age-adjusted longitudinal analyses, total testosterone was associated with incident depressive symptoms . Similarly, age-adjusted analyses showed a positive association between sex hormone-binding globulin and cognitive status in men . In women, age-adjusted associations of androstenedione with baseline depressive symptoms  were found. None of the observed associations remained after multivariable adjustment.The present population-based, longitudinal study revealed inverse associations between sex hormones and depressive symptoms. However, the null finding after multivariable adjustment suggests, that the observed associations were not independent of relevant confounders including body mass index, smoking and physical inactivity. Furthermore, the low number of incident endpoints in our non-clinical population-based sample limited the statistical power and reduced the chance to detect a statistically significant effect. Depression is widely recognized as a major health problem and potential risk factor for increased morbidity and decreased quality of life. The observed sex difference in depressive symptoms prevalence motivated research efforts to investigate the role of sex hormones in this gender gap . Since tHowever, to date, epidemiological and clinical studies on depressive symptoms in women have yielded inconsistent results, showing both, positive and inverse associations between androgens and depression or depressive symptoms.In men, associations between testosterone and depressive symptoms were observed in specific subpopulations and cross-sectional samples , lackingAlthough it is well known, that cognitive functions  and andrHowever, given the preliminary evidence from previous observational studies, limited by an older study population, immunoassay-based measurements or cross-sectional study design, the aim of our study was to investigate cross-sectional and longitudinal associations of a large androgen panel and sex hormone-binding globulin (SHBG) with depressive symptoms and cognitive status in men and women from the general population.The Study of Health in Pomerania (SHIP) is a population-based cohort study in north-eastern Germany. We previously published details of the study design, recruitment, and procedures . In brieWe assessed sociodemographic and behavioral characteristics and medical history conducting a computer-assisted personal interview. Mean daily alcohol consumption was calculated using beverage-specific pure ethanol volume proportions. Participants were considered being physically inactive, when they participated in physical training less than one hour a week during winter or summer. Participants were divided into three categories of smoking habits: current, former, and never-smokers. The sample was stratified into pre- and post-menopausal women, applying a previously published categorization: all women <40 years of age and between 40 and 60 years who reported menstrual cycle were classified as pre-menopausal and all women ≥60 years of age, together with all women between 40 and 60 years who reported no menstrual cycle were classified as post-menopausal . ParticiThe primary outcome, depressive symptoms, was defined by two self-reported questionnaire items of the Composite International Diagnostic-Screener (CID-S), based on core diagnostic questions from the Composite International Diagnostic Interview: Have you experienced more than one period in your life in which 1) you felt more than two weeks almost daily sad or depressed? 2) you suffer more than two weeks almost daily from loss of interest, fatigue or shiftlessness? If question 1) and 2) were answered positively, the participant was classified as depressive . The sec−9 with a = SHBG (nmol/L) -TT (nmol/L) +23.43, b = a2 + (4*23.43*TT (nmol/L))] and c = 2*23.43*109 for a standard average albumin concentration of 4.3 g/dL [A detailed description of the performed TT and ASD measurements was previously published . Briefly4.3 g/dL . Androgeth, p75th). Continuous hormone concentrations were naturally log transformed to normalize their distributions and categorized by age-specific quartiles (for each 10-year age group). First, we implemented age- and multivariable-adjusted generalized Poisson regression models with robust standard errors to examine cross-sectional and longitudinal associations of TT, fT, ASD, and SHBG with depressive symptoms. Effects were presented as relative risk (RR) together with 95% confidence interval (CI) for continuous (increase per standard deviation) and categorized (with quartile one as reference) analyses. The P-value for trend was calculated by involving androgen quartiles as an ordinal score into the regression model. In longitudinal analyses, the sample was restricted to individuals without prevalent depressive symptoms at baseline. Next, we analyzed associations of androgens and SHBG concentrations with cognitive status  using linear regression models. Effects are presented as β-coefficients together with 95% CI. We used QQ-plots to test the normality of regression residuals. The multivariable model was adjusted for age, body mass index, smoking status (three categories), alcohol consumption, physical inactivity and hypertension. Additionally, an extended multivariable model included adjustment for occupational status, educational level, and civil status. When analyzing the change in mini mental status, we adjusted all models additionally for baseline MMSE. Multiplicative interaction terms between each hormone and covariate was investigated in multivariable models. Given a number of significant interactions terms , all analyses were performed sex-specific. During sensitivity analyses, multivariable regression models among women were stratified for hormone therapy (women using hormone therapy N = 445), OC use  and menopausal status  and time and date of blood sampling in all individuals. Furthermore, we excluded all participants using antidepressants , women with self-reported hysterectomy/bilateral oophorectomy (N = 230 women) and additionally adjusted all analyses of androgens for SHBG. Due to sample attrition over the 10-year follow-up period, we also adjusted regression models for possible drop-out bias, by using inverse probability weights. To replicate previously reported findings from selected study populations [Categorical data are given as percentage and continuous data as mean (standard error) or median  .After multivariable-adjustment we found no associations between androgens and change in MMSE in both sexes . StratifThe present population-based study revealed no statistically significant associations between androgens and depressive symptoms in cross-sectional and longitudinal analyses. Additionally the non-significant findings after multivariable-adjustment highlight the relevant role of cofactors in the association between androgens and depressive symptoms.The present null finding is in line with previous observational cohorts like the Rancho Bernardo study  and releLongitudinal analyses in men revealed inverse associations between TT and depressive symptoms in 5- and 10-year follow-up, but only in age-adjusted models. The link between low TT and depressive symptoms is described in previous meta-analysis  and obseIn women, we observed a borderline significance for the inverse association between ASD and baseline depressive symptoms. Not only in men, but also in women androgen concentrations decrease continuously with age with about to 50% before menopause compared to 20-year-old women. A population-based study among German women showed that symptoms as depressive mood increased from 20% in 18–29 years old, to 48% for 50–59 year old . AssociaIn terms of the secondary outcome cognitive status, we found no associations between androgens and change in mini mental status in both sexes. The effect of testosterone on cognitive performance is not yet clear. On one side and in line with our findings, long-term testosterone-administration in older men in a recent randomized, double blind, placebo-controlled trial, did not improve cognitive function . On the Only in men and in line with previous research , we obseImportant strengths of our study are the availability of a large population-based sample and the longitudinal study design. An additional strength is the androgens measurement by LC-MS/MS instead of immunoassay, providing a reliable assessment of androgen status, especially in the low concentrations range of women.This study has several limitations that could affect the generalizability of these findings. We defined depressive symptoms only by CID-S, but this time-efficient diagnostic screening tool of depressive symptoms is commonly used in large population-based samples. In this study, we observed that prevalence of depressive symptoms in longitudinal analyses was low, compared with baseline prevalence of depressive symptoms . This could be explained with the healthy responder effect, assuming that individuals who respond and especially repeatedly respond in follow-up to the examination invitation are healthier than individuals who did not respond. Thus, there is a risk that the study is falsely negative due to high attrition rate among individuals with depressive symptoms. However, previous studies describing prevalence of depression in both old  and younAmong men and women from the general population, androgens and SHBG were not independently associated with depressive symptoms. Since all of the observed significant associations were rendered non-significant after multivariable adjustment, these findings underline the relative importance of body composition and health-related lifestyle for the link between androgens and depressive symptoms. Furthermore, the non-clinical population-based nature of our study sample yielded a low incidence of depressive symptoms and thereby limited statistical power and reduced the chance to detect statistically significant estimates during longitudinal analyses. To further elucidate the exact interplay of androgens, depression and relevant confounders, future investigations in large-scale longitudinal studies are needed.S1 Table(DOCX)Click here for additional data file.S2 Table(DOCX)Click here for additional data file.S3 Table(DOCX)Click here for additional data file.


Background: Early exposure to enteropathogens has been associated with malnutrition in children in low-resource settings. However, the contribution of individual enteropathogens remains poorly defined. Molecular diagnostics offer an increase in sensitivity for detecting enteropathogens but have not been comprehensively applied to studies of malnutrition.Objective: We sought to identify enteropathogens associated with malnutrition in Bangladesh.Design: Malnourished children [weight-for-age z score (WAZ) <−2] aged 6–23 mo in Dhaka, Bangladesh, and identified by active community surveillance were enrolled as cases, and normal-weight children (WAZ >−1) of the same age and from the same community were enrolled as controls. Stools were collected at enrollment and, for cases, after a 5-mo nutritional intervention. Enrollment and follow-up stools were tested by quantitative polymerase chain reaction for 32 enteropathogens with the use of a custom-developed TaqMan Array Card.Results: Enteropathogen testing was performed on 486 cases and 442 controls upon enrollment and 365 cases at follow-up. At enrollment, the detection of enteroaggregative Escherichia coli , Campylobacter spp. , heat-labile enterotoxin-producing E. coli , Shigella/enteroinvasive E. coli , norovirus genogroup I , and Giardia  were associated with malnourished cases, and the total burden of these pathogens remained associated with malnutrition after adjusting for sociodemographic factors. The number of these pathogens at follow-up was negatively associated with the change in WAZ during the intervention , whereas the number at enrollment was positively associated with the change in WAZ .Conclusions: A subset of enteropathogens was associated with malnutrition in this setting. Broad interventions designed to reduce the burden of infection with these pathogens are needed. This trial was registered at clinicaltrials.gov as NCT02441426. Shigella and heat-labile enterotoxin-producing Escherichia coli (LT-ETEC)E. coli (EAEC)  , Campylolobacter , 6, Crypporidium –9, Giard <−2 were eligible for inclusion as a case. Children were eligible if they had diarrheal symptoms upon presentation; however, children with diarrhea that was severe  or persistent (defined as a duration >14 d) were excluded. Contemporaneous controls, frequency matched by age, sex, and area of residence, and a WAZ >−1 were actively enrolled from the same neighborhood (the Bauniabadh area of Mirpur). Enrollment was performed from November 2009 to December 2012. After enrollment, cases were given 2 daily macronutrient supplements [Pushti packets  of 35; thus, a qC > 35 was considered negative, as described previously  as described previously (Campylobacter (ProSpecT) and E. histolytica, Giardia, and Cryptosporidium (TechLab). Testing for diarrheagenic E. coli was performed by pooling 5 lactose-fermenting colonies for multiplex PCR for shiga toxin 1 (stx1), shiga toxin 2 (stx2), heat-stabile enterotoxin (ST), heat-labile enterotoxin (LT), intimin (eae), bundle-forming pilus (bfpA), invasion plasmid antigen H (ipaH), AggR-activated Transporter (gene A) (aatA), and AggR-activated Island (gene C) (aaiC).A quantitative polymerase chain reaction (qPCR) of stools was performed with the use of a custom-developed TaqMan Array Card that compartmentalized probe-based real-time PCR assays for 32 enteropathogens. This was performed in 2015 on all available archived stools from the enrollment as well as from cases after the completion of the 5-mo intervention. First, nucleic acid was extracted from specimens with the QIAamp Fast DNA Stool mini kit (Qiagen). Two external controls, MS2 bacteriophage and Phocine herpesvirus, were added to the stools during extraction to confirm nucleic acid extraction and amplification efficiency. The analytic cutoff of each pathogen was a quantification cycle .A total of 500 cases and 480 controls were enrolled, of whom 95% (928/980) had an enrollment stool available, and 73% (365/500) of cases had both repeat anthropometry and qPCR performed on a follow-up stool , LT-ETEC , Shigella/enteroinvasive E. coli (EIEC) , norovirus genogroup II , and Giardia  was associated with malnutrition at enrollment after adjusting for enrollment age, sex, and the presence of diarrhea at enrollment , and the detection of these pathogens was associated with malnutrition in a dose-dependent fashion, an association that persisted after adjusting for sociodemographic factors . Similar associations as those between qPCR pathogen detection and low WAZ were observed between qPCR pathogen detection and stunted compared with nonstunted children .qPCR detection of EAEC , Campylobacter , C. difficile , Giardia , and Trichuris  . We then examined the enrollment stools of cases to identify whether these pathogens were associated with the change in WAZ during follow-up , were marginally positively associated with the change in WAZ during the follow-up period.The 5-mo nutritional intervention did not substantially increase the WAZ of the malnourished cases (mean ± SD change in WAZ: 0.09 ± 0.50). For most pathogens, there was no correlation between detection at enrollment and follow-up in the same individual, with the exception of Giardia, EAEC, and Campylobacter were again associated with a lower change in WAZ during follow-up, whereas Shigella/EIEC detection was not associated with the change in WAZ. The total number of these pathogens detected in follow-up stools was also negatively associated with the change in WAZ .Finally, we examined follow-up stools from cases to identify pathogens associated with a lower change in WAZ over the 5-mo follow-up period . The detCampylobacter, EAEC, LT-ETEC, Shigella/EIEC, norovirus genogroup II, and Giardia was associated with malnourished cases (defined herein as WAZ <−2). Furthermore, infection with these malnutrition-associated pathogens remained strongly associated with malnutrition after controlling for potential confounding by sociodemographic factors. The effect sizes were clearly reduced by adjusting for these factors, suggesting that they are independently associated with both enteropathogen infection and malnutrition. For each individual pathogen, there was no significant association between quantitative detection and malnourished cases. We presume that this is because with high quantities of most of these pathogens diarrhea becomes likely  used in this study, although widely endorsed, is broad and may limit the specificity of the identified associations. Second, a case-control study does not allow for an elucidation of the temporal relation between enteropathogen infection and malnutrition. Malnutrition has a well-established association with immunosuppression , and thuIn summary, screening for enteropathogens directly from stool specimens with highly sensitive molecular assays revealed associations between several prevalent enteropathogens and malnutrition. The association between the burden of these enteropathogens and malnutrition persisted after adjusting for sociodemographic factors. This study provides a list of specific pathogens that are putative contributors to poor growth and development in children in low-resource settings and provides a potential target for future interventions.


The specific role played by most of these species specific unique miRs are yet to be discovered. However, these newly discovered miRNAs might serve as novel targets for therapeutic intervention or biomarkers for parasitic infections.Helminthic infections fall under neglected tropical diseases, although they inflict severe morbidity to human and causes major economic burden on health care system in many developing countries. There is increased effort to understand their immunopathology in recent days due to their immuno-modulatory capabilities. Immune response is primarily controlled at the transcriptional level, however, microRNA-mediated RNA interference is emerging as important regulatory machinery that works at the translation level. In the past decade, microRNA (miRNA/miR) research has advanced with significant momentum. The result is ever increasing list of curated sequences from a broad panel of organisms including helminths. Several miRNAs had been discovered from trematodes, nematodes and cestodes like let-7, miR155, miR-199, miR-134, miR-223, miR-146, and fhe-mir-125a etc., with potential role in immune modulation. These miRs had been associated with TGF-β, MAPK, Toll-like receptor, PI3K/AKT signaling pathways and insulin growth factor regulation. Thus, controlling the immune cells development, survival, proliferation and death. Apart from micromanagement of immune system, they also express certain unique miRNA also like  The healthy state of an individual is governed by controlled regulation of various systemic processes and its protection from pathogens/allergens it encounters. This protection against pathogens is taken care by our immune system. The two arms of immune defense, innate and adaptive, work synergistically to protect host against pathogenic agents and to maintain immune homeostasis. One common strategy by which pathogens could challenge host immunity to promote their adaptive fitness is through the manipulation of crosstalk interactions between innate immune receptors/molecules. Extra-cellular parasites are smartest of the pathogens, which can evade immune system detection for a very prolonged period and can make conducive environment for themselves. Helminthic parasites, from the phylum Platyhelminthes (including trematodes and cestodes) and the phylum Nemathelminthes (nematodes) are the most common parasitic infectious agents affecting human being in tropical and developing countries. According to Global Disease Burden estimate approximately more than one billion people living in poor regions of sub-Saharan Africa, Asia and the Americas are getting exposure to one or more helminthic species . Apart fHelminths infection and the resultant host immune response is consequence of an extended vibrant co-evolution between the host and parasite with constant fine-tuning. For parasites it is a necessity to trick the host from developing an effective immune response, to find a right niche for maturation and propagation and to do so without killing or excessively harming the host. Conversely, the host has to generate an effective immune response to expel the parasite and minimize its harmful consequences, at the same time not damaging its own tissues and compromising its ability to effectively respond to other pathogens. The host mechanisms of defense against these multicellular parasites range from primary barriers to the most elaborate signaling mechanisms, which involves different kind of cells and molecules, which are capable of non-specific and specific recognition and elimination of invasive agents. All immune evasion mechanisms are extremely embedded in the fine details of the molecular machinery that regulate the immune response. These parasites have evasion mechanisms in place that depends upon several factors like life cycle stage, route of infection and the microenvironment in which they survive in host etc. How higher vertebrate immune system fights off/or learns to live with worm infections has been a hot topic for long and extensively studied, but many questions remain unanswered.C. elegans in 1993, where the gene expression of lin-14 was found to be down regulated by miRNA lin-4 . These small RNAs range from 18 to 30 nucleotide in length and are crucial regulators in the silencing of target genes in a wide range of metazoans, plants, and fungi . Among tNA lin-4 . Thus fiNA lin-4 . HoweverDicer is a RNase III enzyme that cleaves precursor miRNA (pre-miRNA) into miRNA duplex and Argonaute is the major executor of miRNA/siRNA function, respectively. Several protozoan parasites  lack coding genes for the key miRNA processing enzymes DICER and Argonaute, hence are not capable of synthesizing their own miRNA . But thein-silico tools like mireap, miRDeep2, miRAnalyzer or by homology mapping, miRNAs have been computationally or experimentally investigated in more than 35 helminthic parasites  more than 620 pre-miRNAs are currently listed at miRBase1 of parasitic origin. The mature miR transcripts are result of elaborate processing (∗ strand. The guide strand is loaded into the RISC (RNA induced silencing complex) which targets mRNA for degradation or translation repression and miR∗ is degraded. Which strand will be retained depends on the relative thermodynamic stability of the two ends of the duplex intermediate . Among the conserved family of miRs identified by this approach, miR-71 was having the highest number of reads followed by mir-277 and miR-215, suggesting their role in parasite’s survival and metabolism inside the host. These parasite derived novel miRs can be used to assess the cancer risk associated with liver fluke infection. In an in-vitro study using H-69 lung cancer cell line, C. sinensis. Among the miRNAs, seven of them  were mainly associated with esophageal adenocarcinoma, breast cancer and colorectal carcinoma, suggesting the role of these miRs in cell-proliferation and cell-signaling.This food-borne carcinogenic liver fluke causes infection in human called Clonorchiasis. Approximately 35 million people are globally infected by this parasite, especially in Asian countries like China, Japan, Vietnam and Korea . The liv applied , they idC. sinensis infected mice at 2, 8, and 16 weeks post-infection using miRNA-microarray and validated it by quantitative real-time PCR (qRT-PCR). They noticed 349 miRNAs were differentially expressed during infection, out of which 143 were down-regulated and 206 were up-regulated. These all dysregulated miRNAs were potentially involved in the pathological processes of clonorchiasis by regulating various signaling pathway like cancer-related, TGF-β, MAPK, TLR, PI3K/AKT signaling pathways. Interestingly 169 of these dysregulated miRNAs were predicted to be involved in the TGF/Smads signaling pathway which plays an important role in the biliary fibrosis caused by C. sinensis.Recently, Fasciola hepatica and F. gigantica causes fasciolosis in mammals. It completes its life cycle in its intermediate-host snail and definitive-host mammals. It is estimated that worldwide 2.4–17 million people are infected with Fasciola spp. and another 180 million are at risk of infection in Americas, parts of Europe, South Africa, the Middle East and Asia . Human mir-125 family members have been previously identified as decisive players in immune system development, immunological host defense and in cancer  causes infection in pigs and humans. Approximately 807 million people are infected and 4.2 billion are at risk of infection globally (C. elegance. Their germline is siRNA pathway dependent, whereas embryogenesis and larval development is dependent on miR pathway. The miR expression profile of male and female worm shared two novel miRs Asu-miR-share-391 and Asu-miR-share-404, the expression of miR-391 was more abundant in male than in female (The roundworm nematode globally . Ascarisn female . But theTrichinella spiralis is a food borne intracellular helminth that causes trichinellosis in animals. Humans get infection by ingestion of undercooked pork infected with its larvae (T. spiralis. They analyzed the sequence against C. elegans and Brugia malayi miRdataset as reference and identified 11 and 12 conserved miRNA, respectively, with one unique miR. The miR expression profile showed miR-1, let-7, miR72, miR87 and miR-124 were highly abundant in the muscle larvale, suggesting it’s potential role in growth and metabolism. The one novel miR identified was trs-mir-0001 and it’s role in regulation and as signature miR for Trichinellosis needs to be further studied.s larvae  and it es larvae . The pars larvae . Chen etAngiostrongylus cantonensis also known as Rat Lungworm is a prime causative agent of eosinophilic meningitis and eosinophilic meningoencephalitis in humans (A. cantonensis. They found miR-71, miR-1, and miR-60 were abundant in male and female parasites but the relative expression or copy number was higher in males, implying their role in adult maturation and development. But they could not identify any novel miR. There were stage specific miR expression observed in young and adult worm, though the miR-1, miR-77, and miR-44 were abundant in young and adult worm stage suggesting they might be crucial for the survival (The parasitic nematode n humans . Inside survival . As the survival .Echinococcus spp., Taenia spp., and Diphyllobothrium which generally cause asymptomatic intestinal infection which can be sometimes associated with mild abdominal pain or nausea. Their larval stage can penetrate through intestinal mucosa and travel to elsewhere causing infection with varied pathology.Cestodes are parasitic flatworm causing chronic zoonotic diseases. They include organisms like Echinococcus granulosus, E. multilocularis, and E. canadensis. These cestode parasites complete their life cycle in two mammalian hosts, ungulates as intermediate host and humans happen to be accidental host. Two of them, E. granulosus and E. multilocularis are known to cause most of the human infections. The miR expression profile of E. granulosus was studied for its different developmental stages and the protoscolex and cyst wall both showed the expression of miR-2, miR-9, miR-10, miR-27, let-7, and miR-71 except for miR-125 which was present only on protoscolex (E. granulosus had higher expression of miR-2 and miR-125 and their sequence showed variability, suggesting that it is due to binding to various 3′UTR targets. Interestingly, four novel miRs have been also identified in this parasite, namely miR-4988, miR-4989, miR-4990, and miR-4991. In a recent miR profiling in E. canadensis and it’s comparison with E. granulosus for identification of conserved miR and novel miR it was shown that let-7 and miR-71 were found to be highly abundant and accounted for about 50% of whole miR expression levels indicating role of these miRs in parasite’s survival in the intermediate host. miR-9 was also found to be highly expressive and miR-4989 expression appeared only in cyst wall samples. The miRnomes of echinococcus species showed expression of conserved miR profiles mir-36, mir-67, mir-92, mir-184, mir-281, miR-307, mir-1992, and miR-3479 which were previously thought to be lost in Echinococcus (in vitro experiment on RAW267.4 cells after 12 h of treatment (E. granulosus eggs revealed an array of miRs for resistant and non-resistant haplotypes to infection. The resistant haplotypes had differentially expressed miR-21-3p, miR-134-5p, miR-542-5p, and miR-671 these miRs were found to be associated with NFκβ pathway and increased resistance to infection suggesting their role in inflammation, though further functional analysis needs to be undertaken (The causative agents of echinococcosis or hydatid are toscolex . These mnococcus . The miRnococcus . In a streatment . The rolreatment . It doesreatment . The intdertaken .Mesocestoide corti is helminthic parasite that infects rats/mice. Though it does not infect human being it is used as a model organism for studying immunopathogenesis of class cestoda, of which Taenia is most important genus having mammals as host and T. solium is the most important parasite as it infects human. Larvae of taenia infect central nervous system causing neurocysticercosis, which is one of the most common cause of acquired epilepsy in developing world (M. corti have two life stages, tetrathyridia larvae and strobilated worm, and recently both were exploited for expression study of the miRNAs. The stage specific novel miR like miR-12071 was found in tetrathyridia stage and three conserved miRs found in storbilated worms were miR-2b, miR-7a, and miR-3479b. Besides these novel miRs there were certain common miRs and are highly expressed in both stages like bantam-3p, let-7-5p, miR-10-5p, miR-71-5p, and miR-4989-3p (Echinococcus spp. has already been discussed, its expression is found abundant in M. corti as well. The miR-71 in C. elegance has been shown to be associated with increased longevity via insulin-receptor/phosphatidylinositol 3-kinase pathway (M. corti needs further investigation. The up-regulated miR-36b also found in Echinococcus is associated with regenerative potential in planarians (M. corti tetrahyridia stage this miR is thought to control proliferation by asexual reproduction (M. corti were absent in Echinococcus. M. corti expression profile reveals lots of potential miRs for further understanding of biological processes. Further assessment of post-transcriptional regulation of these miR in host-parasite interaction will enable a better understanding of class cestoda.ng world . M. cort-4989-3p . The sig pathway . But wheanarians  and rapianarians  in M. cooduction . The miRHelminthic infections are receiving great attention off late, due to their wide spread infection and newly established role as novel regulators of development, sex differentiation, drug resistance and immune modulators. Hence, microRNAs present in these parasites are also getting increasingly higher attention from research community to understand their role in immune modulation and auto-immune disorders and to explore their therapeutic potential.Figure 2. As there are still several concerns to be addressed regarding the complete biological functions of miRNAs in the development/growth/maturation of parasitic helminths and its contribution in the formation of host pathology. Another major unanswered question is whether inhibitors of worm-specific miRNAs can kill parasitic helminths? And if yes, what will be commercial viability of that drug, as at present helminthic infections are largely treated by cheap protein inhibitor based drugs.By now, several studies had indentified different miRNA expression in various parasitic infections and the number of parasitic diseases in which the role of miRNAs has been confirmed is continuously increasing. The emerging role of miR in the helminthic diseases had brought a range of novel miRs, circulatory miRs and differentially expressed miRs at various life stages of helminths. miRNAs are small and comprise of a known sequence that is often completely conserved across species, which makes it a very attractive features from a drug development standpoint. A lot of conserved miRs are found across different classes, these miRs could give molecular cues of the processes common to all and hence can be used as broad range targets for entire class. The important and varied roles of miRNAs had identifid these molecules as valid targets for intervention strategies. However, targeting miR has its own challenges, as evident from the profiles of immune responsive miRs like miR-155, miR-146a/b etc., they are common host’s responsive miRs but it’s difficult to say if they have a common target or follow the common signaling mechanism as one miR can have multiple targets. microRNAs can serve as good and reliable biomarkers due to their high stability in paraffin-embedded tissues from clinical samples or in human plasma raised the possibility that miRNA expression analysis may be a useful tool to define disease states . CurrentDevelopment of microRNA-based therapeutics has proved more challenging than anticipated. The slow progress mainly stems from the general technical challenges with RNAi-based therapeutics including delivery, stability and avoidance of activating immune responses. Though, the presence of evolutionary conserved miRs which were found to be present in all the species indicating their common origin and probably similarity in action infuse interest to researchers. Determining miRNA functions by applying gene knock out technique will be difficult. Many miRs are processed from introns of protein coding genes or multicistronic units containing multiple miRNA, thus making single miRNA knock-out animals difficult. Another big question among researchers are whether they operate through targeting single critical gene or do they act broadly by regulating minor effects on multiple targets, as suggested by evolutionary consideration. Parasite’s miRNAs also regulate host target genes and there is increasing evidence that pathogens exploit host miRNAs to aid replication and survival. miRNAs are essential for the rapid responses to environmental changes and the regulation of development involved in parasitism.The main advantage of miRNA targeting based therapeutics over protein targeting is rather than intercepting a single target as in the case of selective protein inhibitors, miRNAs can regulate entire gene programs. Importantly, the outcome is tuning of target expression instead of blunting it, which should be less detrimental to healthy tissues. This demands for the identification of precise targets of each miRNA, which would considerably expand our understanding of parasitic helminths biology. Improved genome assembly/annotation together with comparative analysis will also help in target gene prediction through identification of conserved miRNA binding sites. However, to achieve this we must acknowledge that the relevant tools for miRNA target prediction are still lacking for all most every parasitic worm and helminths miRNA research needs major effort before we can use/target miRNA for treatment. It will be important to examine effects of helminth miRNAs on both parasite and host gene expression, any parasite-induced changes in host miRNA expression or copy number could also influence helminth tropism.Nowadays, miRNA is a hot issue in medical research field with huge potential. Despite the promising advancement in the applied areas of miRNA, several major theoretical and practical challenges remain to be resolved before this technique can be used in clinical application for treatment/diagnosis of infectious diseases. First, more basic investigations will be required to further examine the functional role of miRNAs in parasitic and other infectious diseases. Although, miRNAs can inhibit mRNAs by translational suppression or cleavage, others possible unknown mechanism could lead to translational or post-translation suppression. Second, the biological functions and packaging of extracellular miRNAs needs to be better understood. A number of studies had proposed that micro-vesicles containing miRNAs might be involved in the inflammatory site’s microenvironment. However, this will need more detailed knowledge about the detailed mechanism of miRNA specific function and action within complex disease pathways in one or more than one etiological agents, with tissue specific manner. Effort should be made to study the gene mutation frequency in miRNA and their target gene. Use of synthetic miRNA containing multiple binding sites or using small molecule inhibitor to reduce interaction between miRNAs and their targets will be useful to increase the efficiency and efficacy of miRNA based therapeutic tools. miRNA mimics, which are small, chemically modified double stranded RNA molecule that mimic endogenous mature miRNA can also be used to increase the target specificity and better delivery. Applying systems biology approaches, to describe role and activity of miRNA under conditions of homeostasis and disease may open new avenues. Another important avenues to be of immense importance is the delivery system, success of miRNA in therapeutic application relies on accurate delivery at the target site. A lot has to be done on this aspect. Finally before translation into clinical practice, all circulating miRNA findings require further steps of validation and an accurate standardization of all pre-analytical and analytical procedures, in order to control for all potential technical biases. Integration of data from whole genome atlas or miRBase will aid in future discoveries. Hence, use of miRNA for targeted therapy in near future is bright and impulsive at this moment; nevertheless, with ever increasing and rapid discoveries in this filed is certainly promising and have lots of potential. So, despite these caveats miRNA has strong potential to lead to therapeutic targeting of parasite cellular pathways as well as altering host-parasite interactions that influence parasite survival, which will be very beneficial for treatment of helminthic infections and personalized medicine for the pathology induced by helminthic infections. This calls for the complete understanding of receptor-targeted delivery of miRNA mimics or inhibitors to affected cells/tissues that may be critical for decreasing off-target effects, and for augmenting the utility of miRNAs.NA, ST, AS, PM, AM, and AP designed the manuscript, NA, ST, AK, and AP wrote the manuscript. NA, PM, AM, and AP drafted and critically evaluated the 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. The reviewers FFC, HLMG and handling Editor declared their shared affiliation, and the handling Editor states that the process nevertheless met the standards of a fair and objective review.


Exposure to childhood trauma (CT) is a global major public-health and social-welfare problem worldwide. CT increases the vulnerability to major psychiatric conditions including psychosis and is associated with poorer clinical outcome. CT affects the development of brain structures such as hippocampus, possibly through oxidative stress and neuroinflammation, two mechanisms linked to psychosis. We therefore hypothesized that there is an interplay between oxidative stress and CT in psychosis patients. We thus explored in early psychosis patients the relationships between CT and i) hippocampal volume, ii) antioxidant systems; and iii) clinical and cognitive outcomes.We studied a cohort of 118 early psychosis patients, 36 were exposed to CT . In a subgroup of 48 patients (18 CT), hippocampal volume was determined by MRI. Antioxidant systems were quantified in blood for the whole cohort. Markers were: glutathione peroxidases (GPx) activity which appeared as a peripheral correlate of brain GSH levels ; peroxiredoxine levels (Prx); Thioredoxine (Trx). Psychopathology (PANSS) and neuropsychology (MCCB) were assessed. The various groups were segregated by linear discriminant analysis.The previously observed decreased hippocampal volume in patients and association of small hippocampal volume with high blood GPx activity (reflecting high oxidative status)  was due to the contribution of the traumatized group. Indeed, this association was absent in the no-trauma group, suggesting that the smaller hippocampus is linked to a redox dysregulation. To explore that point further, four groups were then formed, according to trauma and oxidative status: (i) noCT-lowGPx, (ii) noCT-highGPx, (iii) CT-lowGPx and (iv) CT-highGPx. Group CT-highGPx only had smaller hippocampi.In CT patients, small hippocampal volume was associated with high GPx activity, while hippocampal volume was similar in CT patients with low GPx activity (CT-lowGPx) and in patients not exposed to CT. Interestingly, other antioxidant defense systems such as Trx and oxidized Prx levels correlated negatively with GPx in CT-lowGPx group, suggesting that the Trx/Prx system is able to compensate for changes/decreases in GPx activity. Moreover, CT-lowGPx patients perform better than the other patients on speed of processing, verbal memory and attention tests.In contrast, hippocampal volume was decreased in CT patients with high GPx activity (CT-highGPx) compared with CT-lowGPx patients and patients not exposed to CT. There was no correlation between GPx and Trx/Prx system in this group. CT-highGPx patients had more severe positive, negative and disorganized symptoms than the other patients.We report that traumatized psychosis patients with high peripheral oxidation status (high GPx) had smaller hippocampal volumes and more severe clinical symptoms, while those with lower oxidation status (low GPx) had better cognition and appear to activate a compensatory antioxidant regulation by the Trx/Prx system.These results suggest that, in early psychosis patients, traumatic experiences during childhood interact with different redox systems and have long term neuroanatomical and clinical impacts. Therefore, redox pathways such as GPx, Trx and Prx systems represent important translational biomarkers for patient selection and stratification in order to aid in diagnostics and treatment decision at early stages of the disease.


Mycobacterium leprae (M. leprae) infected individuals who develop leprosy, is still substantial. Solid evidence exists that individuals living in close proximity to patients are at increased risk to develop leprosy. Early diagnosis of leprosy in endemic areas requires field-friendly tests that identify individuals at risk of developing the disease before clinical manifestation. Such assays will simultaneously contribute to reduction of current diagnostic delay as well as transmission. Antibody (Ab) levels directed against the M.leprae-specific phenolic glycolipid I (PGL-I) represents a surrogate marker for bacterial load. However, it is insufficiently defined whether anti-PGL-I antibodies can be utilized as prognostic biomarkers for disease in contacts. Particularly, in Bangladesh, where paucibacillary (PB) patients form the majority of leprosy cases, anti-PGL-I serology is an inadequate method for leprosy screening in contacts as a directive for prophylactic treatment.Despite elimination efforts, the number of Between 2002 and 2009, fingerstick blood from leprosy patients’ contacts without clinical signs of disease from a field-trial in Bangladesh was collected on filter paper at three time points covering six years of follow-up per person. Analysis of anti-PGL-I Ab levels for 25 contacts who developed leprosy during follow-up and 199 contacts who were not diagnosed with leprosy, was performed by ELISA after elution of bloodspots from filter paper.Anti-PGL-I Ab levels at intake did not significantly differ between contacts who developed leprosy during the study and those who remained free of disease. Moreover, anti-PGL-I serology was not prognostic in this population as no significant correlation was identified between anti-PGL-I Ab levels at intake and the onset of leprosy.In this highly endemic population in Bangladesh, no association was observed between anti-PGL-I Ab levels and onset of disease, urging the need for an extended, more specific biomarker signature for early detection of leprosy in this area.ISRCTN61223447ClinicalTrials.gov  Mycobacterium leprae, which causes skin and nerve damage. Despite worldwide efforts to eliminate leprosy, the number of infected individuals who develop leprosy, is still substantial. Household contacts of new leprosy patients are especially at risk. Early diagnosis of leprosy is key in preventing lifelong handicaps as well as transmission. This requires field-friendly tests that identify individuals at risk of developing the disease before they develop clinical symptoms so that they can receive (prophylactic) treatment. Measuring antibody levels directed against the M.leprae-specific phenolic glycolipid I (PGL-I) provides an indication of the bacterial load. To identify whether anti-PGL-I Ab levels correlate with the development of leprosy in contacts of newly diagnosed leprosy cases, we analyzed these levels in 25 contacts who developed leprosy during 6 years of follow-up and 199 contacts who were not diagnosed with leprosy at 3 time points in 6 years. This study showed that anti-PGL-I Ab levels at intake did not significantly differ between contacts who developed leprosy during the study and those who remained free of disease. Therefore, anti-PGL-I Ab levels alone do not represent a practical tool for prediction of which household contacts will develop leprosy in an endemic area such as Bangladesh, with high levels of patients with paucibacillary leprosy. This stresses the need for a diagnostic test composed of a biomarker signature consisting of multiple biomarkers.Leprosy is an infectious disease caused by the bacterium  Mycobacterium leprae (M. leprae), which causes damage to the skin and peripheral nerves[M. leprae infected individuals, carrying substantial numbers of bacteria but (yet) lacking clinical symptoms. Thus, early detection and subsequent (prophylactic) treatment of asymptomatically infected individuals as well as subclinical disease is essential to reduce transmission.Leprosy is an infectious disease caused by al nerves. The higal nerves. Bangladal nerves. Althougal nerves. In Bangal nerves. Indirecal nerves. The conM. leprae infected individuals without any symptoms[M. leprae infection or predict progression to clinical disease[M. leprae-specific immunity in those at risk of developing disease. Therefore, investments in large-scale longitudinal follow-up studies, allowing intra-individual comparison of immune profiles in leprosy patients’ contacts, is essential to evaluate which markers correlate with progression to disease and may be used as predictive biomarkers.Diagnosis of leprosy is still largely dependent on clinical signs and symptoms and detection of acid fast bacteria. However, user friendly lateral flow assays provide new possibilities for rapid diagnosis of leprosy patients in early stages of the disease or of  symptoms, 5. Suchl disease. In viewM. leprae phenolic glycolipid I (PGL-I) is an extensively studied antigen on the outer surface of the mycobacterium[5.bacterium. The exibacterium–7, has abacterium. AlthougIn a previously conducted cluster randomized controlled trial, designated the COLEP study, the effect of single dose rifampicin versus placebo in preventing leprosy in close contacts of newly diagnosed leprosy patients was studied between 2002 and 2009 in a leprosy endemic area in the Northwest of Bangladesh, 12. To Contacts of leprosy patients were voluntarily recruited as part of the COLEP study  in 2002 and 2003 in the districts Rangpur and Nilphamari in the northwest of Bangladesh, which is a leprosy endemic area, 12. EliA random sample was taken from 28,092 contacts of leprosy patients recruited within the COLEP study. A totalThe COLEP study represents a unprecedented field trial for leprosy, because it includes valuable longitudinal analysis of contacts and thus is uniquely suited to identify the predictive value of biomarkers. However, the COLEP study did not collect blood samples from contacts as the only samples collected was blood on filter paper. Therefore, this limited biomarker analysis to anti-PGL-I Ab only.In this part of the country, the new case detection rate of leprosy was 3.21 per 10,000 in 2002 . In these cases leprosy was diagnosed by active and passive case detection. In 2002 and 2003 random samples from the general population were taken to calculate the prevalence of previously undiagnosed leprosy (PPUL). In the contact group of the COLEP study, the PPUL rate was 73/10,000, compared to 15.1/10,000 in the samples taken from the general population. These cases were found by active door-to-door screening.M. leprae specific native PGL-I glycolipid was synthesized and coupled to human serum albumin . This was generated with support from the NIH/NIAID Leprosy Contract N01-AI-25469 and obtained through the Biodefense and Emerging Infections Research Resources Repository .Disaccharide epitope 2,3-di-O-methylrhamnopyranoside) of M. leprae PGL-I were detected as described previously[p-nitrophenylphosphate substrate  was added. Antibodies  against M. leprae PGL-I were detected as previously described[450), after correction for background OD above 0.150, were considered positive. This threshold was determined by a threefold multiplication of an average EC value.Antibodies  against reviously, 14, 15.450 values correlated well .As quality control, anti-PGL-I IgM levels were determined for 10 Dutch leprosy patients by ELISA using serum as well as blood spots on filter paper: Although IgM levels were higher for 9 individuals in sera, all seropositive individuals were also positive using blood spots and ODhttps://www.R-project.org).Multivariable logistic regression was used to calculate adjusted odds ratios for the level of ant-PGL-I Ab levels at intake, and corrected for age and sex. A p-value ≤ 0.05 was used as a cut-off for statistical significance. To investigate the association of changes in anti-PLG-I Ab from baseline to the time of development of leprosy, generalized linear mixed models were used. The dependent variable was the development of leprosy at a time point and the differences in anti-PLG-I Ab levels from baseline were included as independent variables. To adjust for the correlation between intra-individual measurements we included a random intercept for each subject. The difference between the anti-PGL-I Ab levels between contacts of MB or PB index patients was calculated using a t-test comparing averages. All analyses were performed in R version 3.2.0  showed tet al.[Barretto et al. showed tet al. as well as the other studies discussed above, since development of leprosy was not associated with the level of anti-PGL-I seropositivity at intake, clearly indicating that also in Bangladesh anti-PGL-I Ab tests lack the ability to early diagnose leprosy amongst leprosy contacts[A recent meta-analysis among household contacts of new leprosy patients in French Polynesia, Zaire, Papua New Guinean, Venezuela, Brazil, India and Philippines shows th contacts–23, if uM. leprae antigens[et al[Most of the leprosy patients’ contacts in our study developed PB leprosy (21 out of 25), which offers an explanation for the lack of increase of anti-PGL-I titers at leprosy diagnosis. Importantly, in Bangladesh, the percentage of PB cases amongst new leprosy cases is generally higher than in other countries in Asia, especially southeast Asia where predominantly MB patients are found[ antigens, which iens[et al found thens[et al, 25, shoens[et al.M. leprae due to continued exposure to an unknown source. Also, in the absence of complete ‘sterilisation’ of M. leprae in these subjects, the bacterium may start to multiply again after the effect of rifampicin has waned. So although the antibody titre may certainly have decreased due to single dose rifampicin, it is unknown whether this effect would be apparent after 2 years, at the moment of first blood sampling.As a part of the COLEP trial, half of the new leprosy contacts received placebo and the other half single dose rifampicin. It can be expected that single dose rifampicin could lower the anti-PGL-I antibody level in subjects with a relatively high bacterial load. However, it is unknown how soon and to which extent the antibody titre is suppressed. Furthermore, there is also the possibility that subjects become re-infected with M. leprae exposed individuals will progress to disease complicated. For example, certain helminth-derived proteins can bias the host immune response towards an anti-inflammatory Th2 response, which may facilitate M. leprae growth or progression to MB leprosy[M. leprae, causing the development of clinical disease[Furthermore, it is worthy to note that leprosy is a complicated disease with different immunological processes playing a role in disease progression, which in turn are affected by factors such as genetics, co-infeB leprosy. Furtherl disease.M. leprae exposure. In particular, the combination of humoral and cellular biomarkers increased efficiency to distinguish M. leprae infected from non-infected individuals, patients from contacts, or lepromatous from tuberculoid patients compared to serology alone[Recent advancements in leprosy biomarker research have shoogy alone, 15. In ogy alone, 30, fieogy alone, 25, thaogy alone, allowinM. leprae, current research is focused on identification of predictive biomarker profiles associated with early stage leprosy, consisting of multiple cellular and humoral (disease-specific) biomarkers. Early diagnosis of leprosy and subsequent appropriate multidrug therapy (MDT) will not only decrease severe nerve damage and subsequent lifelong handicaps, but also significantly contribute to further decrease of M. leprae transmission. This study shows that measurement of anti-PGL-I Abs alone is not sufficient to predict the development of clinical leprosy amongst household contacts of newly diagnosed leprosy cases in (highly) endemic area such as Bangladesh. Because of the high number of PB patients in Bangladesh, using anti-PGL-I titers as a screening test to discriminate which contacts to treat, may lead us to miss a lot of potential new cases.In view of the dichotomy of the leprosy spectrum in terms of immunity against Ethical clearance was obtained from the Ethical Review Committee of the Bangladesh Medical Research Council in Dhaka (ref. no. BMRC/ERC/2001-2004/799). All subjects were informed verbally in their own language  about the study when they were invited to participate. Written consent was received from each adult, while a parent or guardian had to sign the consent form for children who participated in the study.S1 Checklist(DOCX)Click here for additional data file.


To determine the changes in interhemispheric functional coordination in patients with obstructive sleep apnea–hypopnea syndrome (OSAHS) relative to controls, using a recently introduced method of analysis: voxel-mirrored homotopic connectivity (VMHC).z-values of alterations in VMHC in brain region were correlated with clinical characteristics.Twenty-nine patients with OSAHS and twenty-six normal sex-, age-, and education-matched controls were recruited and resting-state functional magnetic resonance imaging data were obtained. We employed VMHC to analyze the interhemispheric functional connectivity differences between groups. The t = 5.749, P < 0.001), apnea–hypopnea index , oxygen desaturation index , and Epworth sleepiness scale , but significantly lower scores on the Rey–Osterrieth complex figure test-immediate recall . On the same basis, the VMHC showed significant increases in bilateral calcarine cortex and precuneus. Moreover, significant, positive correlations were found in only these areas between the AHI and the VMHC change coefficients .Compared with controls, patients with OSAHS had significantly higher scores for body mass index (We found a memory defect in patients with OSAHS. The correlation between the abnormal VMHC and the AHI in patients with OSAHS suggested that AHI might be a key factor in cognitive dysfunction, which might offer new insights into the neural pathophysiology underlying OSAHS-related cognitive deficits. Obstructive sleep apnea–hypopnea syndrome (OSAHS) is a common, chronic sleep disease, whose characteristics include repeated episodes of partial or complete obstruction of the upper airway, and continual diaphragmatic efforts to breathe during sleep . DemograResting-state functional magnetic resonance imaging (MRI) based on blood-oxygenation-level dependent contrast (perhaps better known as BOLD contrast) has been widely used in various functional connectivity (FC) studies ranging from examinations of psychiatric disorders to neurological conditions , as wellAs the largest commissural fiber bundle, the corpus callosum can facilitate communication and integration of emotional, cognitive, motor, and sensory information between the two cerebral hemispheres , 26. DesTo explore this issue, we used calculations of voxel-mirrored homotopic connectivity (VMHC) to investigate interhemispheric FC. This method is a voxel-wise measurement of functional homotopy that reveals the synchrony of resting-state BOLD fluctuations between a voxel in one hemisphere and its mirror-image counterpart in the other. VMHC has been successfully applied to investigate interhemispheric functional homotopy in several diseases including autism, cocaine addiction, and schizophrenia –34. VMHCTwenty-nine newly diagnosed, untreated patients with OSAHS and twenty-six normal gender-, education-, and age-comparable controls were recruited by the Sleep Laboratory of the Otolaryngology-Head and Neck Surgery Department of Zhongda Hospital, Southeast University. No patient had comorbid conditions such as heart failure or central nervous system diseases  or a history of psychotropic drug use. Patients with a history of airway, laryngeal, or pharyngeal surgery were also excluded. All controls were healthy, without any history of brain abnormalities or heart failure. All participants in both the OSAHS and control groups were between 20 and 60 years of age, right-handed, and free of metallic implants or other contraindications for MRI scan.This study was carried out in accordance with the recommendations of the Institutional Ethics Committee of Zhongda Hospital, Southeast University, Nanjing. Before the study, all participants gave written, informed consent in accordance with the Declaration of Helsinki and the protocol was approved by the Institutional Ethics Committee of Zhongda Hospital, Southeast University, Nanjing.We used the mini-mental state examination (MMSE) to screen for dementia and cognitive impairments . The ReyThe night before functional MRI (fMRI) scanning, the OSAHS and control groups were asked to undergo polysomnography monitoring (YH-2000A system) in the Department of Otolaryngology-Head and Neck Surgery of Zhongda hospital. All participants were prohibited from drinking alcohol or caffeinated beverages for 12 h before polysomnography. For all participants, polysomnography was performed from 11:00 p.m. to 07:00 a.m. A standard encephalogram , chin electromyography, electrocardiography, oculography, oral cavity and nasal cavity airflow, movements of the chest and abdomen, oximeter, physical position, and stertor were recorded. Two indexes related to sleep were then calculated in accordance with the criteria of the American Academy of Sleep Medicine , 39. TheFunctional and structural MRI scans were performed on all participants at the Radiology Department of Zhongda Hospital using a 3.0 T MRI scanner . We adopted earplugs to reduce scanning noise and foam padding to decrease head motion. All participants were asked to close their eyes and not sleep, not to think about anything in particular, and to avoid any head motion as far as possible during scanning. The rs-fMRI data were acquired axially by applying an echo-planar imaging sequence sensitive to BOLD contrast. One hundred eighty functional images were obtained covering the whole brain . High-spatial-resolution, T1-weighted images were also obtained from each participant by applying a magnetic prepared gradient echo sequence, yielding 176 structural images . Furthermore, 20 fluid-attenuated inversion-recovery images (perhaps better known as FLAIR images) were acquired to screen for structural brain lesions . The total duration of scanning was 12 min, 23 s.Functional MRI data analysis was performed using DPARSFA (rs-fMRI Advanced Edition) with statistical parametric mapping SPM8. A totalz-values using Fisher’s r-to-z transformation to enhance the stability of the values. The resulting values were considered a measure of VMHC and were used for the final intergroup analysis.We used REST software to compute the VMHC. The Pearson’s correlation coefficient between the remaining time series of each voxel and that of its mirrored interhemispheric voxel was calculated and the homotopic FC was measured . Subsequt-test was used for VMHC-map analysis to investigate altered interhemispheric FC in patients with OSAHS. P < 0.05 was considered statistically significant, and cluster sizes were set at 63 voxels, as determined by Monte Carlo simulations using the AFNI AlphaSim program. Because of the influence of micromovements from volume to volume on the FC . However, the patients with OSAHS had significantly higher scores for BMI , AHI , ODI , and ESS , but significantly lower scores for CFT-immediate recall  compared with controls. No significant differences were observed between patients with OSAHS and controls in CFT-delayed recall , LMT-immediate recall , LMT-delay recall , or score on the MMSE .In our study, 55 participants  were included in the final data analysis. The demographic and clinical data of all participants are presented in Table Patients with OSAHS showed significantly increased VMHCs in the calcarine cortex and precuneus compared with healthy controls. However, relatively decreased VMHCs were not seen in patients with OSAHS. The details are presented in Figures r = 0.378, P = 0.043). In addition, a significant positive correlation was found in the calcarine cortex between VMHC values and AHI  .In patients with OSAHS, a significant positive correlation was found in the precuneus between VMHC values and AHI (In this study, we adopt a VMHC approach to investigate possible differences in interhemispheric FC between patients with OSAHS and controls. We found a significant increased VMHC in the precuneus and calcarine cortex in patients with OSAHS compared with controls. What is more, there were significant positive correlations between the AHI and the VMHC in these brain areas.Few past studies have reported increased activities in the precuneus in patients with OSAHS. However, here we found significantly increased VMHC in the precuneus of such patients. Huynh and coworkers found no difference in gray matter volume between patients with moderate-to-severe OSAHS and normal controls, so an increased VMHC was not attributed to structural differences, but possibly to strengthened neural activity . Our finThe precuneus is part of the posterior DMN, which plays an important role in fundamental cognitive functioning, including episodic memory retrieval, visuo-spatial imagery, self-processing, and consciousness , 46. TheApart from any cognitive deficits that can arise from these abnormalities, these changes imply problems in sustained and divided attention that arguably contribute to the well-recognized driving difficulties of patients with OSAHS  and may The calcarine cortex is a main core of the visual recognition network , and hasRecently, a systematic meta-analysis of patients with OSAHS demonstrated co-activations in several bilateral brain regions including amygdala, hippocampus, thalamus, precuneus, and posterior cingulate cortex. This suggested a significant association of the disorder with affective and emotional processing, as well as with memory-related processes . SimilarInterhemispheric functional interactions are at the foundation of the integration of executive control and attentional processing . Our stuAll participants provided written informed consent before the study, and the protocol was approved by the institutional Ethics Committee of Zhongda Hospital, Southeast University, Nanjing.MY, BL, and Z-CH contributed conception and design of the study; Y-TL, H-XZ, TC, and LZ organized the database; Y-TL performed the statistical analysis; Y-TL wrote the first draft of the manuscript; H-JL and Y-QH wrote sections of the manuscript. All authors contributed to manuscript revision, read and approved the submitted version.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.


Multidrug-resistant tuberculosis (MDR-TB) is a growing concern in meeting global targets for TB control. In high-income low-TB-incidence countries, a disproportionate number of MDR-TB cases occur in migrant (foreign-born) populations, with concerns about low adherence rates in these patients compared to the host non-migrant population. Tackling MDR-TB in this context may, therefore, require unique approaches. We conducted a systematic review and meta-analysis to identify and synthesise data on MDR-TB treatment adherence in migrant patients to inform evidence-based strategies to improve care pathways and health outcomes in this group.This systematic review and meta-analysis was conducted in line with PRISMA guidelines (PROSPERO 42017070756). The databases Embase, MEDLINE, Global Health and PubMed were searched to 24 May 2017 for primary research reporting MDR-TB treatment adherence and outcomes in migrant populations, with no restrictions on dates or language. A meta-analysis was conducted using random-effects models.From 413 papers identified in the database search, 15 studies reporting on MDR-TB treatment outcomes for 258 migrants and 174 non-migrants were included in the systematic review and meta-analysis. The estimated rate of adherence to MDR-TB treatment across migrant patients was 71% [95% confidence interval (CI) = 58–84%], with non-adherence reported among 20% (95% CI = 4–37%) of migrant patients. A key finding was that there were no differences in estimated rates of adherence  or non-adherence  between migrants and non-migrants.MDR-TB treatment adherence rates among migrants in high-income low-TB-incidence countries are approaching global targets for treatment success (75%), and are comparable to rates in non-migrants. The findings highlight that only just over 70% of migrant and non-migrant patients adhere to MDR-TB treatment. The results point to the importance of increasing adherence in all patient groups, including migrants, with an emphasis on tailoring care based on social risk factors for poor adherence. We believe that MDR-TB treatment targets are not ambitious enough. Multidrug-resistant tuberculosis (MDR-TB), defined by resistance to isoniazid and rifampicin, the two front-line antimicrobial drugs used to treat TB, presents substantial barriers to the eradication of global TB due to challenges around diagnosis and successful treatment –4. As a It is estimated that there are over 244 million international migrants worldwide , with raMDR-TB treatment regimens may be of long duration. Whilst a shorter 9-month Bangladesh treatment regimen is available for some patients, in many cases MDR-TB treatment requires an intensive treatment phase up to 8 months in duration, with a further 12-month minimum continuation phase . TreatmeThe aim of this systematic review and meta-analysis is, therefore, to identify and synthesise data on MDR-TB treatment adherence in migrant populations.This research was carried out in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) , and regWe included peer-reviewed papers reporting primary data on MDR-TB treatment adherence in migrants (foreign-born and receiving treatment outside their country of birth). Those studies reporting stipulated WHO outcomes for individuals receiving MDR-TB treatment that could be used as proxies for treatment adherence  were included , 31, as Studies were not excluded based on publication date or language, and non-English papers were translated prior to full-text screening. There were also no restrictions on whether studies considered paediatric or adult populations, or the type of study design. Studies defining migrant status according to ethnic or ancestral background but not country of birth were excluded, as were papers where primary data were not reported .We searched the databases Embase (1947 to 22 May 2017), Global Health (1973 to 24 May 2017), MEDLINE (1946 to 22 May 2017) and PubMed (1993 to 22 May 2017) using a Boolean search strategy with keywords and relevant medical subheadings (MeSH) pertaining to four main themes: migrants, adherence, tuberculosis and drug resistance (including MDR-TB). The terms used were identified by consulting the literature, previous systematic reviews  and expeAdditional relevant papers were also identified through hand searching the bibliographies of publications included after full-text screening, as well as related information sources, including: the Global Fund, Public Health England, WHO and the International Union Against Tuberculosis and Lung Disease. Experts in the field were also consulted to identify additional relevant papers.Two reviewers duplicated the title and abstract screening and full-text screening (LBN and KR), which was carried out using the web-based application Rayyan .Data extraction and quality assessment for all papers included were also conducted by two reviewers (LBN and KR). Using a piloted data extraction form, summary data were extracted on study design, dates, location, patient characteristics, type of treatment, and migrant and non-migrant treatment outcomes in line with WHO outcome measures. Quality assessment was carried out using established appraisal tools. All case series were assessed using the Case Series Critical Appraisal Tool of the Joanna Briggs Institute . Case–cometaprop and metan were used to calculate pooled prevalence and pooled risk ratios (RRs), respectively, with corresponding 95% confidence intervals (CIs) [I2 statistic. Due to the heterogeneity of the included studies, analyses utilised random-effects models [Statistical analysis was carried out using Stata 13 . The comls (CIs) , 40. HetWe estimated the pooled proportion of migrants who were adherent and not adherent to treatment. We carried out analyses for both of these categories, as neither capture individuals who have died. We defined adherent individuals as those reported as cured, having completed treatment or with a successful outcome, utilising these treatment outcomes as indicators of treatment adherence to examine all available evidence comprehensively. Individuals considered adherent have, therefore, had confirmation of MDR-TB cure or have satisfactorily completed a full course of treatment. Successful outcomes cover both of these categories. Those still on treatment were excluded from the adherent variable as data were not available on treatment outcome. However, sensitivity analyses were conducted to examine the effect of these patients on pooled adherence rates across the studies if they were adherent or non-adherent.We defined non-adherent individuals as those reported in the literature within categories: lost to follow-up, treatment default (discontinuation of treatment), treatment failure (which can often be attributed to issues in adherence) and unsuccessful outcome. Patients who transferred out of treatment were excluded from the non-adherent group as data on outcome were not known. A sensitivity analysis was conducted excluding treatment failure, as this outcome may be due to factors other than non-adherence.We also carried out meta-analyses comparing rates of adherence and non-adherence between migrants and non-migrants across the included studies. These meta-analyses excluded studies in which no events occurred in either the migrant or non-migrant arms , alDatabase searches yielded 413 publications, with 234 publications carried forward for title and abstract screening after the removal of duplicates. Of those, 129 citations were excluded. The full texts of 105 publications were screened, including one citation identified through bibliography screening, hand searching of relevant sites, and recommendations from experts. Ninety one records were excluded during full-text screening, and the reasons for their exclusion recorded  , 44, AusA total of 258 migrants with MDR-TB were included in the studies. For nine studies, we were able to disaggregate data for 174 non-migrants with MDR-TB or extensively drug-resistant tuberculosis , 53, 54.The quality of the included studies was high, with the number of criteria met ranging from 7/9 to 11/11 for cohort studies, 7/9 to 10/10 for case series, and 7/9  and 8/9 I2 = 82%) after excluding individuals still on treatment (n = 10) .A meta-analysis was conducted utilising the nine studies for which the outcomes of 179 migrants and 171 non-migrants were disaggregated, enabling a comparison of MDR-TB treatment adherence in these two groups Fig. . MigrantI2 = 67.32%) . In non-migrants, the rate of non-adherence when excluding treatment failure was 3% .Complementary analyses examining rates of non-adherence in migrants were also conducted, as patients who have died are not captured by either measure. Among the 248 migrants with reported MDR-TB treatment adherence outcomes, 61 were considered non-adherent while 17 individuals transferred out of treatment and were excluded. The estimated rate of non-adherence to MDR-TB treatment in migrants was 20% .Rates of non-adherence to MDR-TB treatment were compared between migrants and non-migrants in six studies for which data were available Fig. , and werAdherence rates among migrants on treatment for MDR-TB were estimated to be 71% 95% CI = 58–84%), approaching global treatment adherence targets , and exc–84%, appRates of MDR-TB treatment adherence and non-adherence were also found to be comparable between migrants and non-migrants . These findings challenge previous assumptions that adherence to MDR-TB treatment is likely to be worse in migrants , 59, 60.Social risk factors, for example social deprivation, vulnerable housing, mental health concerns or other comorbidities, have been shown to present barriers to care in migrant populations, and may contribute to poorer treatment adherence –64. BeinThe health service context within which MDR-TB is diagnosed and treated may also be a significant determinant of adherence, and may mediate the effects that social and cultural barriers may have  , 61, 68.Across the included studies, it was also suggested that adherence rates have increased in recent years, which is likely to reflect an improvement in the provision of MDR-TB treatment and increased availability of specialist TB services , 71. WhiThe comparable rates of adherence (and non-adherence) between migrants and non-migrants are in contrast with assumptions that adherence to TB treatment is likely to be worse in migrants , 59, 60,This research represents the first systematic and comprehensive examination of adherence to MDR-TB treatment in migrant populations, to our knowledge. It identifies the need for a stronger evidence base in light of the lack of data collected on migrant status in TB and MDR-TB patients, though this group is a key focus of TB strategies in high-income low-TB-incidence countries given the increased burden of TB and MDR-TB in migrant populations in low-incidence countries , 2, 12, Though this review addresses a significant gap in knowledge on MDR-TB treatment adherence in migrants, the research highlights a number of important limitations in the evidence base that should be taken into account when considering the results. First, the findings should be considered in the context of the use of treatment outcomes as a proxy for adherence, which enabled us to examine the available data comprehensively and highlights the key implications for clinical pathways.The review highlighted the significant lack of research in which data are disaggregated in such a way that makes specific research into treatment adherence in MDR-TB and different risk groups feasible. This significantly limited the number of papers included in the review, with the majority of exclusions at full-text screening being attributed to an inability to disaggregate migrant status or drug susceptibility status in relation to treatment adherence. An additional factor limiting the inclusion of papers in this review is the inconsistent reporting of migrant status in the evidence base or frequent use of ethnicity as a proxy for migration. Whilst the review sought to identify peer-reviewed primary research reporting data on migrant groups comprehensively, papers that have not included routinely utilised migrant terms see the  may not,The total number of studies included in the analysis highlights the insufficient research on the relationship between migration and treatment adherence in MDR-TB. The lack of evidence in this area is concerning in light of the growing emphasis in both policy and practice in high-income countries on targeting migrants in the detection and treatment of MDR-TB –75.Data across the included studies were also heterogeneous, reflecting the diverse migrant populations and settings represented. Whilst the analyses utilised random-effects models, it is also useful to interpret the findings in light of the differences across studies. A further limitation of the available data is the small sample sizes across studies, which are partly attributed to the low incidence of MDR-TB, high rates of loss to follow-up during the lengthy MDR-TB treatment pathway , and our particular interest in migrants as a patient population. This only further highlights the need to strengthen the available evidence base in this area. There is also a risk of publication bias, as clinical data on MDR-TB treatment are not systematically analysed or published. Furthermore, the available data may reflect settings in which migrants are a specific interest group (e.g. due to being overrepresented), leading to decisions to record or stratify data based on migrant status, which was an inclusion criterion for this review.Adherence to MDR-TB treatment is critical both in reducing poorer and costlier individual health outcomes and in preventing the transmission of MDR-TB. Despite the comparable rates of adherence in migrants and non-migrants, there are still a concerning number of individuals failing to complete MDR-TB treatment, enabling the spread of MDR-TB. This, therefore, calls into question whether MDR-TB treatment targets are ambitious enough and highlights the paramount importance of increasing adherence in all patient groups, including migrants, with an emphasis on tailoring care based on social risk factors for poor adherence in addition to migrant status.