Mortality after Staphylococcus aureus bacteraemia in two hospitals in Oxfordshire, 1997-2003: cohort study.
OBJECTIVE
To determine the incidence of methicillin resistant and methicillin sensitive Staphylococcus aureus (MRSA and MSSA) bacteraemia in inpatients and associated mortality within 30 days after diagnosis.


METHODS
Anonymised record linkage study of data from hospital information systems and microbiology databases.


METHODS
Teaching hospital and district general hospital in Oxfordshire.


METHODS
Inpatients aged 18 or over admitted to a teaching hospital between 1 April 1997 and 31 March 2004 and to a district general hospital between 1 April 1999 and 31 March 2004. The main part of the study comprised 216 644 inpatients; patients admitted to haematology, nephrology, or oncology services were not included because most were managed as outpatients.


METHODS
Nosocomial MSSA and MRSA bacteraemia; death in hospital within 30 days after bacteraemia.


RESULTS
Rates of S aureus bacteraemia rose between 1997 and 2003, and MRSA was responsible for this increase. Overall mortality 30 days after bacteraemia was 29%. The crude odds ratio for death after MRSA bacteraemia compared with MSSA bacteraemia was 1.49 (95% confidence interval 0.99 to 2.26).


CONCLUSIONS
The spread of MRSA has greatly increased the overall number of cases of S aureus bacteraemia and has contributed to short term mortality after S aureus bacteraemia.
Wyllie
David H
DH
Nuffield Department of Clinical Laboratory Sciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU. david.wyllie@ndcls.ox.ac.uk
Crook
Derrick W
DW
Peto
Tim E A
TE
D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016470:Bacteremia / Q000188:drug therapy / Q000401:mortality; D015331:Cohort Studies; D003428:Cross Infection; D004739:England / Q000453:epidemiology; D017052:Hospital Mortality; D006767:Hospitals, District; D006769:Hospitals, General; D006784:Hospitals, Teaching; D006801:Humans; D015994:Incidence; D007902:Length of Stay; D008712:Methicillin / Q000627:therapeutic use*; D016106:Methicillin Resistance; D008875:Middle Aged; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000401:mortality*; D013211:Staphylococcus aureus
D000900:Anti-Bacterial Agents; D008712:Methicillin