Staphylococcal bacteraemia:: the hospital or the home?: A review of Staphylococcus aureus bacteraemia at Concord Hospital in 1993

Aims: To examine the risk factors for, and the complications and mortality of, Staphylococcus aureus bacteraemia. Methods: A retrospective case review of patients with S. aureus bacteraemia in 1993 diagnosed at the Concord Repatriation General Hospital, Sydney. Results: Of 104 cases reviewed, 32 were due to methicillin resistant S. aureus (MRSA), 73 were due to methicillin sensitive S. aureus (MSSA) and one was a dual infection. Twenty-eight of the bacteraemias were community-acquired, including one case of MRSA, and 76 were hospital-acquired; 38% had an implanted prosthetic device or graft. The average age (68 years), incidence of underlying diseases and hospitalisation in the past month (26%) did not differ between MRSA and MSSA groups. MRSA was more likely in patients with recent broad-spectrum antibiotic use (53% vs 0, p < .01). Vascular access was the commonest source of sepsis (61%) but in community-acquired cases the source was unknown in 50%. Use of central line access was more predictive of MRSA infection (75% vs 49%, p = .018). In hospital-acquired infection, MRSA sepsis occurred later in the course of the admission (26 days vs eight days, p < .01). Directly attributable mortality was highest in MRSA and community-acquired MSSA infection (9% and 11%) compared with hospital-acquired MSSA infection (1%). Conclusions: Nosocomial S. aureus bacteraemia, particularly MRSA, is a major source of preventable morbidity, which could be addressed by improved infection control of MRSA, antibiotic use and attention to central line catheter use.