Environmental surveillance of fungi and susceptibility to antifungal agents in tertiary care hospitals

Abstract

ABSTRACT This study aimed to evaluate the epidemiology of fungi in environment of tertiary care hospitals and their susceptibility patterns to seven antifungal agents for controlling and preventing fungal infections in patients. Environmental samplings on the surfaces of different parts of hospitals were collected from four university-affiliated teaching hospitals in Iran. Routine and molecular procedures identified isolated fungi, and antifungal susceptibility tests were performed in vitro . Of the 400 samples, 152 presented positive culture results, and 193 fungal species were isolated. Mold fungi accounted for 59.1% (115 species) of isolates. Most isolated fungal species in descending order were 22 Aspergillus flavus (11.4%), 21 Candida albicans (10.9%), 17 Mucor species (8.8%), 16 Penicillium species (8.3%), 16 Candida famata (8.3%), 15 Alternaria species (7.8%), 13 Fusarium species (6.7%), 11 Candida parapsilosis (5.7%), and 10 Aspergillus niger sensu stricto (5.2%). The isolated Aspergillus species revealed relatively low susceptibility to itraconazole and posaconazole with MIC90 values of 8 µg/mL. The MIC90 values of amphotericin and luliconazole in Candida species were 0.5 and 0.064 µg/mL, respectively. In this study, different species of filamentous and yeast fungi with varying susceptibility to antifungal agents were reported from the environment of the studied hospitals. IMPORTANCE Saprophytic fungi can cause nosocomial infections in high-risk patients. These infections are related to high mortality and cost. In the current study, different species of filamentous fungi and yeast were isolated from the environment of the studied hospitals. Some species were resistant to antifungal drugs. We suggest that the future work concentrates on the relationship between the level/quantification of saprophytic contamination in the environment of hospitals and fungal infections in patients.