Outbreak of Candida tropicalis Fungemia in a Neonatal Intensive Care Unit

OBJECTIVE: To describe an outbreak of Candida tropicalis fungemia in a neonatal intensive care unit (NICU), to evaluate the risk factors associated with this infection and the possible mode of nosocomial transmission. DESIGN: Descriptive and case-control study. PATIENTS AND METHODS: Surveillance cultures were taken from hospitalized patients, personnel, and inanimate objects in the NICU. Six patients with C tropicalis fungemia (cases) were compared with C tropicalis culture-negative patients matched for duration of exposure to the NICU (controls). RESULTS: During a five-month period, C tropicalis was isolated from 29 blood cultures of six premature infants. The same organism also was isolated from fingernail samples taken from the ward housekeeper, who had a mild onychomycosis, and an asymptomatic nurse. Other potential reservoirs of C tropicalis were not identified among all the other infants or in the hospital environment. The six patients with C tropicalis fungemia were more likely to have received a larger number of antibiotics (4.0 versus 1.8, P < 0.001) and to have been subjected to a longer duration of total parenteral nutrition (TPN) therapy (8.5 versus 2.67 days, P = 0.004) than the controls. CONCLUSIONS: The risk of fungemia in this outbreak can be attributed to a larger number of antibiotics and a longer period of TPN administered to the patients. Analysis of events suggests that the outbreak may have been the result of cross-infection between staff and patients.