Pseudo-outbreak of Mycobacterium paragordonae in a hospital: possible role of the aerator/rectifier connected to the faucet of the water supply system

Abstract

Background: Pseudo-outbreaks of non-tuberculous mycobacteria (NTM) in association with the water supply system in hospitals have been previously reported. We found that the frequency of NTM isolation in clinical samples increased after the reconstruction and renovation of a hospital in Japan in 2014. Aim: To analyse NTM, their possible relationship with the hospital water supply system, and outcomes of preventive measures. Methods: Environmental samples obtained from the water supply in hospital wards were tested for NTM. On obtaining positive results, the bacteria were further analysed using polymerase chain reaction (PCR). Findings: The PCR products of NTM showed that most samples tested positive for Mycobacterium paragordonae. Because none of the analysed patients developed any disease due to these bacteria, this event was considered a pseudo-outbreak. Investigation of the water supply system revealed that samples obtained from the recently attached aerators/ rectifiers during hospital renovation tested positive for these bacteria. Therefore, measures to remove aerators/rectifiers and prevent patients from drinking tap water in the hospital were introduced. Thereafter, the frequency of NTM-positive samples significantly decreased in the hospital. Conclusion:This study is one of the few reports which reveal the possibility of pseudooutbreaks of M. paragordonae in hospitals, hence raising the question whether aerators/rectifiers should be used in hospitals at all, because their mesh structure may promote NTM proliferation in supplied water. The importance of surveillance of bacteria derived from the environment, particularly after hospital reconstruction/renovation, is re-emphasized.

Considerations for large building water quality after extended stagnation

“…Fixtures such as faucets, aerators, fountains (bubblers), thermostatic mixing valves, showerheads, and shower hoses can be relatively easily removed, cleaned, and/or discarded. Pathogen growth and heavy metal accumulation (e.g., particles of copper, iron, lead) have been associated with these plumbing components (Bédard et al, 2015; Cohen et al, 2017; Huang & Lin, 2007; Kappstein, Grundmann, Hauer, & Niemeyer, 2000; Proctor, Reimann, Vriens, & Hammes, 2018; Shaw et al, 2018; Sydnor et al, 2012; Takajo et al, 2019; Verweij et al, 1998; Wang, Chen, Lin, Chang, & Chen, 2009; Weber, Rutala, Blanchet, Jordan, & Gergen, 1999; Whiley, Giglio, & Bentham, 2015). Thermostatic mixing valves, used in showers and faucets to mix hot and cold water to prevent scalding, have been identified as particularly problematic for the growth of Legionella (Niedeveld, Pet, & Meenhorst, 1986; van der Lugt et al, 2017; Van Hoof, Hornstra, Van Der Blom, Nuijten, & Van Der Wielen, 2014).…”

Considerations for Large Building Water Quality after Extended Stagnation

“…Fixtures such as faucets, aerators, fountains (bubblers), thermostatic mixing valves, showerheads, and shower hoses can be relatively easily removed, cleaned, and/or discarded. Pathogen growth and heavy metal accumulation (e.g., particles of copper, iron, lead) have been associated with these plumbing components Cohen et al, 2017;Huang & Lin, 2007;Kappstein, Grundmann, Hauer, & Niemeyer, 2000;Proctor, Reimann, Vriens, & Hammes, 2018;Shaw et al, 2018;Sydnor et al, 2012;Takajo et al, 2019;Verweij et al, 1998;Wang, Chen, Lin, Chang, & Chen, 2009;Weber, Rutala, Blanchet, Jordan, & Gergen, 1999;Whiley, Giglio, & Bentham, 2015). Thermostatic mixing valves, used in showers and faucets to mix hot and cold water to prevent scalding, have been identified as particularly problematic for the growth of Legionella (Niedeveld, Pet, & Meenhorst, 1986;van der Lugt et al, 2017;Van Hoof, Hornstra, Van Der Blom, Nuijten, & Van Der Wielen, 2014).…”

Mycobacterium paragordonae is an emerging pathogen in human pulmonary disease: clinical features, antimicrobial susceptibility testing and outcomes

“…[ 8 ], Takajo et al . [ 9 ], and Moradi et al . [ 17 ] showed that MPG could also be isolated at an incubation temperature of 37°C.…”

“…Mycobacterium paragordonae (MPG) was first isolated from the lungs of a patient in Korea in 2014 [ 7 ]. As with MG, MPG is also a slow-growing, pigmented (orange) bacterium that is widely found in the environment, such as soil and water, and is often considered a contaminating bacterium that can be recovered from freshwater, pipelines, and laboratory faucets [ 8 , 9 ]. The DNA–DNA affinity comparison between MPG and the MG ATCC 14470 T standard strain was only 46.52%, which met the definition of a new species [ 7 ].…”

“…MPG, like MG, is widely prevalent in the environment and is also an opportunistic pathogen[ 7 ]. Although MPG is relatively less virulent compared to other NTM such as Mycobacterium kansasii , associated pathogenic case reports have been published, MPG can be isolated from lung, spinal infection foci, and ascites specimens [ 9–11 ].…”