Evaluation of blood stream infections by Candida in three tertiary hospitals in Salvador, Brazil: a case-control study

Abstract

Invasive infections caused by Candida spp. are an important problem in immunocompromised patients. There is scarce data on the epidemiology of blood stream candidiasis in Salvador, Brazil. This study evaluates the risk factors associated with candidemia, among patients admitted to three tertiary, private hospitals, in Salvador, Brazil. We conducted a case-control, retrospective study to compare patients with diagnosis of candidemia in three different tertiary hospitals in Salvador, Brazil. Patients were matched for nosocomial, acquired infections, according to the causal agent: cases were defined by positive blood cultures for Candida species. Controls were those patients who had a diagnosis of systemic bacterial infection, with a positive blood culture to any bacteria, within the same time period (+/- 30 days) of case identification. The groups were compared for the main known risk factors for candidemia and for mortality rates. A hundred thirty-eight patients were identified. Among the 69 cases, only 14 were diagnosed as infected by Candida albicans. Candida species were defined in only eight cultures: C. tropicalis (4 cases), C. glabrata, C. parapsilosis, C. guillermondi, C. formata (1 case each). The main risk factors, identified in a univariate analysis, were: presence of a central venous catheter (CVC), use of parenteral nutrition support (PNS), previous exposure to antibiotics, and chronic renal failure (CRF). No association was detected with surgical procedures, diabetes mellitus, neutropenia or malignancies. Patients were more likely to die during the hospitalization period, but the rates of death caused by the infections were similar for cases and controls. The length of hospitalization was similar for both groups, as well as the time for a positive blood culture. Blood stream infection by Candida spp. is associated with CVC, PNS, previous use of antibiotics, and CRF. The higher mortality rate for cases probably better reflects the severity of the underlying diseases, than as a direct consequence of Candidemia.