Nosocomial infections among HIV-positive and HIV-negative patients in a Brazilian infectious diseases unit

BACKGROUND: Some researchers observed that HIV-infected patients have a higher risk of acquiring nosocomial infections (NI). This study compared the incidence of NI among HIV-positive and HIV-negative inpatients. METHODS: Patients from an infectious diseases ward who were classified as positive and negative regarding their HIV status were followed-up for 21 months in a prospective cohort study. Daily surveillance was made with use of Centers for Disease Prevention and Control criteria for NI. RESULTS: NI per 1000 patients-day were 8.16 for HIV-positive patients and 3.94 for HIV-negative patients (P =.01). Central venous catheter (CVC) and urinary catheter utilization was significantly higher among HIV-positive patients than among HIV-negative patients (P <.001). Bloodstream infections (BSI) caused most of the NI, followed by urinary tract infections, vascular infections, and pneumonia. Overall, HIV-positive patients were more likely to have a BSI than were HIV-negative patients (P =.005). When only BSI was analyzed in patients with a CVC, there was no difference in the incidence of BSI between the 2 groups of patients (P =.24). HIV-positive patients were more likely to have an NI caused by Staphylococcus aureus than were HIV-negative patients (P =.04). Other important NI agents in both groups were Acinetobacter baumanii, Klebsiella pneumoniae, Pseudomonas aeruginosa, and coagulase-negative Staphylococcus. CONCLUSIONS: In this study the HIV-positive patients were more likely to have NI than were the HIV-negative patients. Overall, HIV-positive patients are at increased risk for an NI caused either by S aureus or a BSI. Although HIV-positive patients had more CVC-days, there was no difference in the number of BSI among both groups, suggesting that the BSI incidence in the HIV-positive group is not exclusively related to the CVC.