Hospital water filters as a source of Mycobacterium avium complex

Abstract

Bronchoscopes and the filters used for washing them were found to yield high numbers of Mycobacterium avium isolates sharing the same repetitive sequence-based PCR (rep-PCR) fingerprint pattern as M. avium isolates recovered from patient samples collected by bronchoscopy. Water and biofilm samples collected from the bronchoscopy preparation laboratory yielded M. avium, Mycobacterium intracellulare, Mycobacterium malmoense and Mycobacterium gordonae. Several M. avium and M. intracellulare isolates from water samples in the bronchoscopy laboratory had rep-PCR patterns matching those of patient bronchoscopy isolates. Five of the 22 (23 %) M. avium patient bronchoscopy isolates and 42 of the 56 (75 %) M. intracellulare patient bronchoscopy isolates could have been due to contamination from the water supply. INTRODUCTIONReports of the isolation of non-tuberculous mycobacteria (NTM) from contaminated bronchoscopes appear regularly in the literature. Such investigations are usually prompted by the isolation of NTM from patient samples collected by bronchoscopy that are inconsistent with patient symptoms or conditions. In a number of instances, either inadequate bronchoscope disinfection (Rodrigues et al., 2001;Wang et al., 1995;Wheeler et al., 1989) or contamination by a bronchoscope-washing machine (Brown et al., 1993;Gillespie et al., 2000;Gubler et al., 1992;Kressel & Kidd, 2001; Takigawa et al., 1995) was identified as the reason for the presence of NTM in the bronchoscopes. In addition, water used for washing bronchoscopes has been shown to be the source of NTM contaminating bronchoscopes (Bennett et al., 1994;Nye et al., 1990;Stine et al., 1987;Vijayaraghavan et al., 2006). In spite of these studies, there are only two reports where a DNA fingerprinting technique was employed to prove that the water used for washing the bronchoscopes was the source (Bennett et al., 1994;Chroneou et al., 2008).The presence of NTM in the water supplies of bronchoscope-processing laboratories is consistent with their presence in hospital water (du Moulin et al., 1988) and municipal drinking water (Falkinham et al., 2001). However, source identification is not straightforward, as the wide genetic diversity within NTM species requires typing of patient and environmental isolates. In addition, in the absence of NTM colony counts, it is impossible to identify which source might be of primary importance and require remediation.At a large general community hospital, Mycobacterium avium or Mycobacterium intracellulare isolates were recovered from 75 patient bronchoscopy samples collected over the period December 2007-February 2009, whose appearance was inconsistent with patient symptoms or conditions. The objective of our study was to collect samples from the hospital water system and bronchoscopyprocessing laboratory, test them for the presence of mycobacteria, and, if recovered, compare the DNA fingerprints of the patient and environmental isolates. METHODSPatient (bronchoscopy) NTM isolates. Twenty-two M. avium and 56 M. intracellulare...

Cooccurrence of Free-Living Amoebae and Nontuberculous Mycobacteria in Hospital Water Networks, and Preferential Growth of Mycobacterium avium in Acanthamoeba lenticulata

“…M. avium, which is one of the most common causes of NTM lung disease in the United States (3), was also isolated from the faucet in the cleaning facility. M. avium has been isolated from other hospital water networks as well as from household plumbing (36,37).…”

Biofilm Formation by Clinical Isolates and Its Relevance to Clinical Infections

“…In particular, M. avium complex has been recovered from potable household water (Wallace et al 2013 ;Whiley et al 2012 ), as well as hospital water supplies where NTM biofi lms have been implicated in persistent bronchoscope contamination (Falkinham 2010 ) despite sterilization procedures. This may explain prior epidemiologic observations in the South Texas region of the United States correlating the presence of clonally identical NTM species in hospital and municipal water supplies (Conger et al 2004 ).…”

Methodological approaches for monitoring opportunistic pathogens in premise plumbing: A review

“…With regard to NTM and amoebae, for which there is no surveillance guideline for their monitoring in premise plumbing, recent studies generally followed standard methods for microbiological tests or sampling guidelines. Taps and showers were the frequent targets (Falkinham, 2011; Feazel et al, 2009; Ichijo et al, 2014; Kilvington et al, 2004; Thomas et al, 2006), with cisterns, filters, garden hoses and ice machines also sampled in some cases (Covert et al, 1999; Falkinham, 2010, 2011; Thomas et al, 2014). In an epidemiological and environmental investigation of a PAM death, a garden hose, service line hose bib, and toilet tank were also included in household samples, all of which were positive for Naegleria fowleri (Cope et al, 2015).…”