Rapidly growing mycobacteria among pediatric hematopoietic cell transplant patients traced to the hospital water supply

Background: Rapidly growing mycobacteria (RGM) have a predilection for those with immunocompromised states. We report increased isolation of RGM among pediatric hematopoietic cell transplant patients that was traced to the hospital water supply. Methods: Cases of RGM-positive patients were differentiated based on whether they were community-acquired or nosocomial, colonized or infected based on predefined criteria. Medical records of all RGM-positive patients were reviewed and data extracted. Infection control outbreak measures were instituted and an environmental investigation was conducted. Results: Between July 2011 and April 2012, 16 RGM isolates were identified among 15 hematopoietic cell transplant patients, compared with none in the preceding year. After environmental samples were initially grown on media for heterotrophic counts and further speciated, RGM species were identified in the hospital water supply. Conclusions: This outbreak of RGM was traced to an environmental source and was successfully controlled through institution of infection control measures.