Catheter-related Staphylococcus aureus bacteremia in cancer patients - High rate of complications with therapeutic implications

Risk factors for complications of catheter-related Staphylococcus aureus bacteremia (CRSAB) have been studied in the general patient population but have not been well defined in cancer patients. We investigated potential risk factors for intravascular and extravascular complications in these patients. We retrospectively reviewed the records of patients with CRSAB hospitalized at our institution between January 2001 and December 2004. Demographic, clinical, laboratory, and microbiologic characteristics were extracted for the period of hospitalization and up to 3 months thereafter. Intravascular complications were defined as infective endocarditis and/or septic thrombosis. Extravascular complications included septic arthritis, deep tissue abscess, osteomyelitis, septic pulmonary emboli, septic shock, and CRSAB-related death. Ninety-one patients were included in the current study; 63% had solid tumors and the remainder had hematologic- malignancies. The incidence of overall complications was 40% (n = 36); 19% (n = 17) were intravascular. On multivariate analysis, renal failure was associated with an increased risk of overall complications (odds ratio [OR], 12.78; 95% confidence interval [CI], 1.43-114.29; p = 0.0226). Patients with solid tumors were more likely to have intravascular complications (OR, 5.47; 95% CI, 1.11-27.01; p = 0.04369). Risk factors for extravascular complications included hematologic malignancy (OR, 9.56; 95% CI, 2.36-38.77; p = 0.0016) and female sex (OR, 5.25; 95% CI, 1.2-22.99; p = 0.0279). Renal failure is a risk factor for CRSAB complications in patients with cancer. Patients with solid tumors and CRSAB tend to develop intravascular complications, while patients with hematologic malignancies are prone to develop extravascular complications. Hence consideration should be given to extending the duration of therapy beyond 2 weeks.