Bloodstream infections among human immunodeficiency virus-infected adult patients: epidemiology and risk factors for mortality

This study was undertaken to describe the epidemiology and sensitivity pattern of pathogens causing community-acquired (CA) and nosocomial (N) bloodstream infection (BSI) in adult HIV-infected patients and to establish risk factors for mortality. The type of study was a retrospective analysis of BSI episodes prospectively collected through a blood culture surveillance program from January 1991 to December 2006. We used non-conditional logistic regression methods with death as a dependent variable. One thousand and seventy-seven episodes of BSI (6%) occurred in HIV-infected patients out of 16,946 episodes during the period of study. CA and N BSI were 634 (59%) and 443 (41%) respectively. S. pneumoniae and S. aureus were the most frequent pathogens (n = 279, 44%) in CA BSI. Coagulase-negative staphylococci and S. aureus were the most frequent micro-organisms isolated in N cases (n = 169, 38%). Cotrimoxazole resistance was common in CA and N BSI and was caused by gram-negative bacilli (50% and 61% respectively). However, resistance rates to ceftriaxone were low (3%). Crude mortality accounted for 140 cases (13%). The independent risk factors associated with mortality were: liver cirrhosis (OR: 2.90, p = 0.001), corticosteroids treatment (OR: 3.51, p < 0.001), neutropenia (OR: 2.21, p = 0.02), inappropriate empirical therapy (OR: 2.44, p = 0.006), and isolate of C. albicans (OR: 7.58, p = 0.010). BSI in adult HIV-infected patients was often caused by gram-positive pathogens in both CA and N settings. Inappropriate empirical therapy and the presence of other immunosuppressive factors were independent risk factors for mortality. Ceftriaxone could be used as the initial empiric therapy for HIV-infected patients with suspected CA BSI. This study was partially presented at the 18th European Congress of Clinical Microbiology and Infectious Diseases (Barcelona, April 2008).