title: Methicillin-resistant Staphylococcus aureus as a community organism.
abstract: An increase in methicillin-resistant Staphylococcus aureus (MRSA) infections prompted a study of MRSA during a 21-month period in a 600-bed university hospital in southern Texas. MRSA cases were classified as community, nosocomial, or transfer cases. A case-control study of risk factors for community MRSA compared with community methicillin-susceptible S. aureus (MSSA) was performed. Pulsed field gel electrophoresis (PFGE) of whole cell DNA typing was used as a marker of strain identity for 31 consecutive isolates collected during the last 8 months of the study. During the 21 months there were 170 patients with MRSA infection or colonization, an incidence of 0.2 per 1,000 patient-days. Ninety-nine (58%) of 170 isolates were from community cases; the community to nosocomial case ratio was 2:1. No significant risk factors differentiated patients with community MRSA compared with community MSSA. Most community MRSA isolates studied (15 [68%] of 22) had distinct PFGE patterns, as did many nosocomial MRSA isolates (4 [44%] of 9). MRSA isolates were commonly present on admission to the hospital, and multiple MRSA strains were demonstrated among both community and hospital isolates.
authors.affiliation: Department of Medicine, University of Texas Health Science Center at San Antonio, USA.
authors.forename: F
authors.initials: F
authors.lastname: Moreno
authors.forename: C
authors.initials: C
authors.lastname: Crisp
authors.forename: J H
authors.initials: JH
authors.lastname: Jorgensen
authors.forename: J E
authors.initials: JE
authors.lastname: Patterson
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D003428:Cross Infection / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology; D004269:DNA, Bacterial / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D015981:Epidemiologic Factors; D005260:Female; D006801:Humans; D008297:Male; D016106:Methicillin Resistance / Q000235:genetics; D008875:Middle Aged; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D013781:Texas / Q000453:epidemiology
chemical_list: D004269:DNA, Bacterial