An outbreak of Pichia anomala fungemia in a Brazilian pediatric intensive care unit

OBJECTIVE: To report an outbreak of Pichia anomala fungemia that occurred in a Brazilian pediatric intensive care unit (ICU) from October 2002 to January 2004. DESIGN: Unmatched case-control study. METHODS: We randomly selected four control-patients for each case-patient from a list of all patients admitted to the ICU for at least 48 hours during the outbreak. A second control group was composed of all consecutive patients with nosocomial candidemia in the ICU during the outbreak: An environmental study was performed, and genetic relatedness among the clinical isolates was characterized by randomly amplified polymorphic DNA assay. RESULTS: During the study period, 1,046 children were admitted to the pediatric ICU, 17 of whom developed P anomala fungemia (attack rate, 1.6%). The median age was 1.1 years, and the main underlying conditions were congenital malformations (35.3%) and neoplastic diseases (11.8%). The overall mortality rate was 41.2%. Two patients received no antifungal treatment; all of the others were treated with amphotericin B. On multivariate analysis, only the presence of a central venous catheter was significantly associated with P anomala fungemia. The yeast was not found on healthcare workers' hands or in the environment. Molecular studies showed that the outbreak was caused by a single strain. The distribution of risk factors was similar between patients with P anomala fungemia and control-patients with candidemia. CONCLUSIONS: This study highlights the importance of P anomala as an emerging nosocomial fungal pathogen. Patients with P anomala fungernia seem to have risk factors in common with those who have candidemia.