Clinical significance of Staphylococcus aureus infection in patients with chronic liver diseases

Background: Staphylococcus aureus increasingly is recognized as an important pathogen in patients with chronic liver diseases. The purpose of this study was to evaluate clinical features and the outcome of S. aureus infections in patients with chronic liver diseases. Methods: From the database of a surveillance study for S. aureus infections, the data regarding S. aureus infections in patients with chronic liver diseases were analysed and compared with those in patients with other diseases. Results: We identified 298 patients who had chronic liver diseases; 151 (50.7%) patients had cirrhosis, 76 (25.5%) had chronic hepatitis and the remaining 71 (23.8%) had other diseases. The most common type of S. aureus infection in patients with chronic liver diseases was primary bacteraemia (n=68, 22.8%) and 92 (30.9%) patients had concomitant bacteraemia. When compared with other disease group, bacteraemia and bone infection were more frequent in the liver disease group (P<0.05). The 30-day mortality rate of the liver disease group was significantly higher than that of the other disease group (29.4 vs. 16.7%, P<0.001). A multivariate analysis showed that chronic liver disease was a significant factor associated with mortality, along with old age, immunosuppressive treatment, intubated state, indwelling urinary catheter, pneumonia and concomitant bacteraemia. Conclusions: Bacteraemia was the most common type of S. aureus infection in patients with underlying liver diseases, predicting higher mortality rates. The mortality rate of patients with liver diseases was significantly higher than that of patients with other diseases when S. aureus infection developed.