IDENTIFICATION OF CULTIVABLE BACTERIA SPECIES PRESENT IN OUTLET OF WATER TREATMENT SYSTEMS OF HEMODIALYSIS CENTERS

Water microbial quality in hemodyalsis centers is particularly important in medicine. The aim of this study was to investigate cultivable bacteria present in outlet of water treatment systems in hemodialysis centers affiliated to Tabriz University of Medical Sciences.This cross-sectional descriptive study was performed in three hemodialysis wards at the hospitals in 2014. Twenty four samples were obtained from the inlet and outlet of the water treatment systems. Bacterial quality of samples were determined with total and fecal coliform bacteria test, heterotrophic plate count (HPC) by membrane filteration technique on blood agar medium and gram-negative bacteria by membrane filtration technique on EMB agar medium. Isolated colonies were identified using standard biochemical tests. Average of pH, temperature and residual chlorine in outlet samples were obtained 6.9, 14.5 °C and zero mg/l, respectively. Total and feacal coliformbacteria were negative at inlet sample, but was postive in one of the outlet samples. HPC at oultel samples from two centers were higher than standart limits of Association for the Advancement of Medical Instrumentation (AAMI). Gram negative bacteria were the frequent species at all samples. Pseodomonaces spp. and Entrobacter spp. were isolated from most samples. The results demonstrates that water treatment devices at hemodialysis centers at hospitals do not provide enough efficiency for water supply according to the microbial quality standards.