Department of Pediatrics.
Department of Medicine.
Ann Am Thorac Soc. 2023 May;20(5):677-686. doi: 10.1513/AnnalsATS.202209-779OC.
Outbreaks of nontuberculous mycobacteria (NTM) among people with cystic fibrosis (pwCF) have been reported at CF centers with conflicting conclusions. The occurrence of NTM at the UVMC (University of Vermont Medical Center) adult CF program was investigated. Use the HALT NTM (Healthcare-associated Links in Transmission of NTM) toolkit to investigate the healthcare-associated transmission and/or acquisition of NTM among pwCF having genetically similar NTM isolates. Whole genome sequencing of NTM isolates from 23 pwCF was conducted to identify genetically similar NTM isolate clusters (30 or fewer single-nucleotide polymorphism differences). The epidemiological investigation, comparison of respiratory and healthcare environmental isolates, and home residence watershed mapping were analyzed. Whole genome sequencing analysis revealed two clusters of NTM isolates ( and ssp. ) among pwCF. The epidemiologic investigation demonstrated opportunities for healthcare-associated transmission within both clusters. Healthcare environmental isolates revealed no genetic similarity to respiratory isolates. However, ssp. respiratory isolates revealed greater genetic similarity to a hospital water biofilm isolate than to each other. Neither cluster had all subjects residing in the same watershed. This study suggests the healthcare-associated transmission of among pwCF is unlikely at UVMC but supports the healthcare-associated environmental acquisition of ssp. . The presence of genetically similar isolates alone is insufficient to confirm healthcare-associated transmission and/or acquisition. The HALT NTM toolkit standardizes outbreak investigation with genetic analysis, epidemiologic investigation, healthcare environmental sampling, and home of residence watershed identification to test the frequency and nature of healthcare-associated NTM transmission among pwCF.
囊性纤维化 (CF) 患者中非结核分枝杆菌 (NTM) 的爆发已在 CF 中心被报道，但结论不一。本研究调查了佛蒙特大学医学中心 (UVMC) 成人 CF 项目中 NTM 的发生情况。使用 HALT NTM（与 NTM 传播相关的医疗保健联系）工具包来调查具有遗传相似性 NTM 分离株的 CF 患者中与医疗保健相关的 NTM 传播和/或获得。对 23 例 CF 患者的 NTM 分离株进行全基因组测序，以确定遗传相似性 NTM 分离株群（30 个或更少的单核苷酸多态性差异）。对 NTM 分离株进行全基因组测序分析，发现 2 个 CF 患者 NTM 分离株群（ 和 ssp. ）。流行病学调查、呼吸道和医疗保健环境分离株的比较以及家庭居住地流域图绘制均进行了分析。全基因组测序分析显示，两个 NTM 分离株群（ 和 ssp. ）中存在 NTM 分离株。流行病学调查显示，两个群中均存在医疗保健相关传播的机会。医疗保健环境分离株与呼吸道分离株无遗传相似性。然而， ssp. 呼吸道分离株与医院水生物膜分离株的遗传相似性大于彼此之间的遗传相似性。两个群均没有所有患者居住在同一流域。本研究表明，UVMC 中 CF 患者之间的 NTM 不太可能与医疗保健相关，但支持 ssp. 的与医疗保健相关的环境获得。仅存在遗传相似的分离株不足以确认与医疗保健相关的传播和/或获得。HALT NTM 工具包通过遗传分析、流行病学调查、医疗保健环境采样和家庭居住地流域识别，标准化了暴发调查，以测试 CF 患者中与医疗保健相关的 NTM 传播的频率和性质。
