Filamentous fungi in water used in hemodialysis treatment: a persistence challenge for health surveillance

Introduction: Fungi usually are resistant to disinfection and has pathogenic potential; however, they are not legally controlled in hemodialysis water (HW). Objective: Filamentous fungi (FF) were evaluated in HW from a tertiary hospital in southeast of São Paulo state (Brazil) and is a reference medical center providing service to millions of people every year. Method: A total of 84 water samples were collected in seven hydraulic system points during a period of one year and FF was identified by macroscopic and microscopic features. Results: FF were detected in all points ranging from 1 to 334 CFU/100 mL. Nine genera along the hydraulic system were identified, including Acremonium, Alternaria, Aspergillus, Beltrania, Bipolaris, Cladosporium, Exophiala, Fusarium, and Penicillium. Conclusions: Most fungi are ubiquitous and some cause human infection and mycotoxins producers. The various genera found reveal possible failures in treatment and distribution system, either through inadequate hygiene practices or infusion of these microorganisms into the pipes. FF detection is needed bearing mind immunological vulnerability of patients under hemodialysis treatment requiring continuous health surveillance actions.