Infectious disease consultation for Staphylococcus aureus bacteremia improves patient management and outcomes

BACKGROUND: Staphylococcus aureus bacteremia (SAB) is a common, severe infectious disease (ID) with accepted standards of care. METHODS: A retrospective cohort study of all 233 SAB cases at the Minneapolis Veterans Affairs Medical Center between October 2004 and February 2008 was performed to measure the impact of ID consultation on conformance to standards and patient outcomes. Outcomes were classified as survived without relapse, relapsed, or died without relapse. Infectious disease involvement was classified as consultation, curbside, or no involvement. RESULTS: Infectious disease involvement occurred in 179 (77%) of 233 cases. Management conformed to accepted standards in 162 (82%) of 197 cases evaluable for conformance. Infectious disease involvement was associated with increased conformance in univariable analysis and multivariable analysis adjusted for propensity for ID consultation (odds ratio [OR], 5.9; 95% confidence interval [CI], 2.5-13.8). Relapse occurred in 14 (9%) of 156 cases in which therapy conformed to standards compared with 8 (23%) of 35 cases in which therapy did not conform to standards (P = 0.045). Relapse was more common in older patients (OR, 1.05; 95% CI, 1.01-1.09) and in cases without ID involvement (OR, 3.02; 95% CI, 1.003-9.1). Death was associated with greater Charlson index scores (OR, 1.89; 95% CI, 1.4-2.5). Of 111 cases with definitely or possibly infected devices, relapse occurred in 9 (9.8%) of 92 cases in which the device was wholly or partially removed compared with 6 (32%) of 19 cases in which the device was left in place (P = 0.02). CONCLUSIONS: Infectious disease involvement in SAB cases was associated with increased adherence to accepted standards and fewer relapses. Infectious disease consultation should be performed for all SAB cases.