Archana Aravindrao Dambal 1 , Aisha Mahantesh Parande 2 , Rekha M. Choudiah 3 , Mahboob Pasha 4 , Vijayanand B. Halli
BACKGROUND Dialysis units need regular prophylactic disinfection of the dialysis water production and distribution circuit without which there can be chronic inflammation among patients using the facility. The aim of the study is to present here our experience in containing an episode of microbial contamination of dialysis water. MATERIALS AND METHODS Our haemodialysis unit had a single pass reverse osmosis plant with facility for pretreatment of raw water and a distribution loop of medical grade PVC (polyvinyl chloride) feeding haemodialysis machines, bicarbonate preparation and dialyser reprocessing areas. After installation, the Reverse Osmosis (RO) membranes and distribution loop were disinfected every fortnight using formalin. Cultures of product water were sent from various sites in the product water loop every month. RESULTS From January to April 2011, 15 water samples out of 52 water samples grew Pseudomonas aeruginosa with a colony count over 200 Colony-Forming Units (CFU). The average monthly number of haemodialysis was reduced from 84.75 to 65. Two patients had intradialytic pyrexia and two others had mild lower respiratory infection. So, the reverse osmosis plant and product water distribution system were repeatedly disinfected using 2% formalin and 1% bleach ensuring contact time and thorough rinsing to address persistent cultures. When these measures could not eradicate microbial growth, the system was sanitised with Gramicid (48% w/w H2O2 + 500 ppm Ag) and all traces of the disinfectant were rinsed away before resuming haemodialysis. CONCLUSION The microbial contamination of dialysis water was eradicated by Gramicid and not by bleach or formalin without any adverse effects after thorough rinsing.