A total of 101 episodes of Staphylococcus aureus bacteraemia were evaluated for the factors influencing prognosis. The overall episode mortality rate and the mortality rate due to bacteraemia were 43.6 and 21.8%, respectively. Episodes with methicillin-resistant S. aureus (MRSA) bacteraemia had a significantly higher overall mortality rate (58.7 vs. 30.9%, P < 0.01) and mortality rate due to bacteraemia (32.6 vs. 12.7%, P = 0.02) when compared with episodes caused by methicillin-sensitive S. aureus (MSSA). The multivariate analysis revealed that the underlying disease, presence of infective endocarditis, septic shock and central intravascular catheter and methicillin resistance of S. aureus were the five independent risk factors associated with a higher mortality rate. (C) 2000 Elsevier Science B.V. and International Society of Chemotherapy. All rights reserved.