Decreased Incidence of Methicillin-Resistant Staphylococcus aureus Bacteremia in Intensive Care Units: a 10-Year Clinical, Microbiological, and Genotypic Analysis in a Tertiary Hospital.
There are limited long-term data on the trends in incidence and characteristics of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia (MRSAB) in intensive care units (ICUs) in which infection control measures have been adopted. We evaluated the trend of incidence and changes in characteristics of MRSA bacteremia in ICUs at a tertiary-care hospital over 10 years using prospective cohort data. ICU-acquired bacteremia was defined as S. aureus bacteremia (SAB) that occurred 48 h or more after ICU admission. MRSA isolates were collected and subjected to microbiological and genotypic analyses. A total of 529 SAB episodes were identified among 367,175 ICU patients. Of these episodes, 288 (54.4%) were ICU acquired, 238 (82.6%) of which were MRSAB. The incidence density of ICU-acquired MRSAB decreased from 1.32 per 1,000 patient-days to 0.19 per 1,000 patient-days (a decrease of 20% annually; P < 0.001 for trend), whereas that of non-ICU-acquired MRSAB fluctuated and did not decrease significantly. The decline in ICU-acquired MRSAB was due to lower catheter-related infection and less pneumonia. Rates of persistent bacteremia and 12-week mortality also fell significantly. A total of 183 isolates were collected from 238 ICU-acquired MRSAB cases. There were no significant changes in the geometric means of vancomycin MICs, vancomycin heteroresistance, or the sequence types of MRSA isolates over time. Chlorhexidine MICs decreased (P < 0.001 for trend) in association with a decline in frequency of the qacA or qacB gene that was related to reductions in specific spa types. The incidence of MRSAB in ICUs has decreased dramatically over time, but most of the microbiological and genotypic characteristics of MRSA isolates have not changed.
['Kim|Haein|H|', 'Kim|Eun Sil|ES|', 'Lee|Seung Cheol|SC|', 'Yang|Eunmi|E|', 'Kim|Hee Sueng|HS|', 'Sung|Heungsup|H|0000-0002-6062-4451', 'Kim|Mi-Na|MN|0000-0002-4624-6925', 'Jung|Jiwon|J|', 'Kim|Min Jae|MJ|', 'Kim|Sung-Han|SH|', 'Lee|Sang-Oh|SO|0000-0003-1381-8787', 'Choi|Sang-Ho|SH|', 'Woo|Jun Hee|JH|', 'Kim|Yang Soo|YS|', 'Chong|Yong Pil|YP|0000-0003-1672-3185']
D016470:Bacteremia D003428:Cross Infection D006801:Humans D015994:Incidence D007362:Intensive Care Units D055624:Methicillin-Resistant Staphylococcus aureus D011446:Prospective Studies D013203:Staphylococcal Infections D013211:Staphylococcus aureus D062606:Tertiary Care Centers
incidence methicillin-resistant Staphylococcus aureus bacteremia intensive care unit genotype vancomycin MIC