Background. Both total antimicrobial use and specific antimicrobials have been implicated as risk factors for healthcare-associated methicillin-resistant Staphylococcus aureus (HA-MRSA) infection. Aims. The aims of the study were: 1.to explore predictors of a new HA-MRSA infection in comparison with a new healthcare-associated methicillin-sensitive Staphylococcus aureus (HA-MSSA), 2. to thoroughly assess the role of recent antibiotic use qualitatively and quantitatively. Methods. The time-period for our study was from October 1997 through September 2001. Applying strict criteria, we identified two groups of inpatients, one with a new HA-MRSA infection and one with a new HA-MSSA infection. We recorded demographic, clinical and antibiotic userelated data up to 30 days before the positive culture date.Results.We identified 127 and 70 patients for each group respectively. Two logistic regression models were carried out to assess the role of antimicrobial use (qualitatively and qualitatively). In model I, duration of hospital stay, presence of chronic wounds, aminoglycoside and fluoroquinolone use retained statistical significance. In model II, duration of hospital stay and history of intubation during the last month stood out as the only significant predictors of a subsequent HA-MRSA infection. No siginificant differences in outcome were noted.Conclusions. The length of exposure to the hospital environment may be the best predictor of a new HA-MRSA infection. Use of aminoglycosides and fluoroquinolones may also stand independently along with presence of chronic ulcers and exposure to surgical procedures. No independent association between quantitative antibiotic use and subsequent HA-MRSA infection was documented.