Preece Clair L, Wichelhaus Thomas A, Perry Audrey, Jones Amanda L, Cummings Stephen P, Perry John D, Hogardt Michael
Microbiology Department, Freeman Hospital, Newcastle upon Tyne, United Kingdom.
Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom.
J Clin Microbiol. 2016 Jul;54(7):1797-1803. doi: 10.1128/JCM.00471-16. Epub 2016 Apr 20.
Isolation of nontuberculous mycobacteria (NTM) from the sputum of patients with cystic fibrosis (CF) is challenging due to overgrowth by rapidly growing species that colonize the lungs of patients with CF. Extended incubation on Burkholderia cepacia selective agar (BCSA) has been recommended as an expedient culture method for the isolation of rapidly growing NTM in this setting. The aim of this study was to assess five selective media designed for the isolation of Burkholderia cepacia complex, along with two media designed for the isolation of mycobacteria (rapidly growing mycobacteria [RGM] medium and Middlebrook 7H11 agar), for their abilities to isolate NTM. All seven media were challenged with 147 isolates of rapidly growing mycobacteria and 185 isolates belonging to other species. RGM medium was then compared with the most selective brand of BCSA for the isolation of NTM from 224 sputum samples from patients with CF. Different agars designed for the isolation of B. cepacia complex varied considerably in their inhibition of other bacteria and fungi. RGM medium supported the growth of all isolates of mycobacteria and was more selective than any other medium. NTM were recovered from 17 of 224 sputum samples using RGM medium, compared with only 7 samples using the most selective brand of BCSA (P = 0.023). RGM medium offers a superior option, compared to other selective agars, for the isolation of rapidly growing mycobacteria from the sputum of patients with CF. Furthermore, the convenience of using RGM medium enables routine screening for rapidly growing NTM in all submitted sputum samples from patients with CF.
从囊性纤维化（CF）患者痰液中分离非结核分枝杆菌（NTM）具有挑战性，因为CF患者肺部定殖的快速生长菌会过度生长。推荐在洋葱伯克霍尔德菌选择性琼脂（BCSA）上延长培养时间，作为在这种情况下分离快速生长NTM的一种便捷培养方法。本研究的目的是评估五种设计用于分离洋葱伯克霍尔德菌复合体的选择性培养基，以及两种设计用于分离分枝杆菌的培养基（快速生长分枝杆菌[RGM]培养基和Middlebrook 7H11琼脂）分离NTM的能力。用147株快速生长分枝杆菌和185株其他菌种的菌株对所有七种培养基进行了测试。然后将RGM培养基与最具选择性的BCSA品牌进行比较，以从224份CF患者的痰液样本中分离NTM。设计用于分离洋葱伯克霍尔德菌复合体的不同琼脂在抑制其他细菌和真菌方面差异很大。RGM培养基支持所有分枝杆菌菌株的生长，并且比任何其他培养基更具选择性。使用RGM培养基从224份痰液样本中的17份中回收了NTM，而使用最具选择性的BCSA品牌仅从7份样本中回收了NTM（P = 0.023）。与其他选择性琼脂相比，RGM培养基为从CF患者痰液中分离快速生长的分枝杆菌提供了更好的选择。此外，使用RGM培养基的便利性使得能够对所有提交的CF患者痰液样本进行快速生长NTM的常规筛查。
