Pseudo-outbreak of Mycobacterium fortuitum in a hospital bronchoscopy unit

Abstract

Mycobacterium fortuitum survive in different environmental conditions, biofilm formation and resistance to chlorinated disinfectants makes its isolation frequent in hospital environments, even being involved in outbreaks by contamination of medical equipment such as bronchoscopes. We describe a pseudo-outbreak by M fortuitum isolated in samples from 9 patients who underwent bronchoscopy in the pneumology bronchoscopy unit of the University Hospital Complex of the Canary Islands from December 2016 to March 2017. We proceeded to investigate the pseudo-outbreak with a combination of epidemiologic, environmental, and molecular typing data. The source/reservoir of pseudo-outbreak was the hospital water used by the bronchoscope automatic washing machine (without antibacterial filter), so control measures were taken. Molecular typing was performed on 7 strains from 7 patients, and a sample of water was collected from a tap in the pneumology bronchoscopy unit: all of which had the same pattern. Our study demonstrates the presence of nontuberculous mycobacteria in the hospital water supply, and thus the need to take measures against them because they compromise patients' health. We also suggest the need for hospital water quality guidelines in which methods to control and/or eliminate them are established.