Surveillance for nosocomial infections and fever of unknown origin among adult hematology-oncology patients

OBJECTIVE: To determine the incidence of nosocomial infections (NIs) and fever of unknown origin among adult hematology-oncology patients. DESIGN: Prospective surveillance study. SETTING: The 18-bed hematology-oncology unit at the University Hospital Bonn, Bonn, Germany. PATIENTS: All hematology-oncology patients admitted during a total of 8 months in 1998 and 1999. METHODS: Standardized surveillance system based on the Centers for Disease Control and Prevention's National Nosocomial Infections Surveillance system. Rates of NI and fever of unknown origin were calculated for patient-days and patient-days at risk (ie, days with neutropenia of < 500/mm(3) or leukopenia of < 1,000/mm(3)). RESULTS: Of 116 patients hospitalized for a total of 4,002 days (172 admissions; mean length of stay, 25.2 days), 32 (27.6%) had a total of 44 documented NIs (19 bloodstream infections, 15 pneumonias, 7 urinary tract infections, and 3 others). In addition, 33 fevers of unknown origin were documented in 28 patients. No patient had thrush while receiving antifungal prophylaxis. The overall rates for NI and fever of unknown origin were 11.0 and 8.2 per 1,000 patient-days (25.3 and 15.4 per 1,000 patient-days at risk), respectively. The risks for NI and fever of unknown origin were significantly higher during neutropenic days, with 34 (77.3%) of the 44 NIs and 22 (66.7%) of the 33 fevers of unknown origin occurring during 1,345 patient-days at risk. CONCLUSIONS: Prospective surveillance for NIs on hematology-oncology units should include fever of unknown origin as the single most common and clinically important entity. For a meaningful comparison of surveillance data for hematology-oncology patients, the reported infection rates should include rates based on days with neutropenia, for which days with leukopenia could serve as a surrogate marker under routine conditions (Infect Control Hosp Epidemiol 2002;23:244-248).