title: Nasal carriage of Staphylococcus aureus on admission to intensive care: incidence and prognostic significance.
abstract: We retrospectively studied the prevalence of the nasal carriage of methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) on admission to a medical surgical intensive care unit (ICU). We also compared the intensive care survival of MSSA carriers with non-carriers. Records of 678 patients admitted over a 24-month period were retrospectively reviewed. Nasal swabs were taken from 565 patients on admission to the ICU. MSSA was isolated from the anterior nares of 126 (22%) patients, MRSA was isolated in 16 (3%) patients and 423 (75%) patients had no nasal carriage identified. MSSA carriers were more likely to have been admitted to the ICU after less than 24 h hospital stay (28% non-carriers, 44% MSSA carriers) and were significantly younger (mean age of 50 years) than non-carriers (mean age 55 years). The median survival (with confidence intervals (CI)) was 29 days (CI 14-44) in non-carriers, 16 days (CI 10-22) in MSSA carriers and 6 days (CI 4-8) for the MRSA carriers. This difference was significant when MSSA carriers were compared with non-carriers ( p=0.003). The ICU mortality was also significantly higher ( p=0.004) in MSSA carriers (88 of the 423 (21%) non-carriers and 40 of 126 (32%) MSSA carriers died prior to ICU discharge).
authors.affiliation: Department of Intensive Care Medicine, Hope Hospital, Stott Lane, M6 8HD, Salford, United Kingdom.
authors.forename: Richard
authors.initials: R
authors.lastname: Porter
authors.forename: Kandasamy
authors.initials: K
authors.lastname: Subramani
authors.forename: Antony N
authors.initials: AN
authors.lastname: Thomas
authors.forename: Paul
authors.initials: P
authors.lastname: Chadwick
mesh_terms: D002353:Carrier State; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D015994:Incidence; D007362:Intensive Care Units / Q000706:statistics & numerical data; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D009296:Nasal Cavity / Q000382:microbiology*; D015995:Prevalence; D012189:Retrospective Studies; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000302:isolation & purification*; D016019:Survival Analysis