Buckwalter Seanne P, Connelly Brian J, Louison Laura K, Kolesch Jolene M, Herring Senait A, Woodliff Ethan D, Bolster LaSalle Catherine M, Grys Thomas E, Deml Sharon M, Wohlfiel Sherri L, Steinmetz Lory K, Wengenack Nancy L
Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA.
Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Scottsdale, AZ 85259, USA.
J Clin Tuberc Other Mycobact Dis. 2022 Nov 12;29:100340. doi: 10.1016/j.jctube.2022.100340. eCollection 2022 Dec.
Rapid detection of complex directly from clinical specimens is critical for patient care. Mycobacterial culture requires days to weeks for results and therefore many laboratories employ rapid molecular methods for the diagnosis of tuberculosis. There are two FDA-cleared molecular assays for the detection of complex in the United States and both are cleared for testing of respiratory specimens only. The detection of complex in extrapulmonary specimens is often done using laboratory-developed PCR methods. In this work, the verification and subsequent validation of test performance over a decade is detailed for a laboratory-developed PCR assay (MTBRP) that detects complex from respiratory and non-respiratory specimens. The assay also provides information about potential isoniazid resistance. The performance of the MTBRP PCR assay was compared to the Cepheid Xpert MTB/RIF assay in acid-fast smear positive and smear negative specimens and mycobacterial culture for acid-fast smear positive specimens. The MTBRP assay demonstrated 99% correlation with the Xpert MTB/RIF assay using 499 respiratory specimens. The performance of the MTBRP PCR assay compared with mycobacterial culture for 867 AFB smear positive respiratory and non-respiratory specimens demonstrated a sensitivity of 100% and a specificity of 99.1%. This work provides longitudinal evidence using real-world clinical laboratory conditions and specimens to demonstrate that laboratory-developed PCR assays such as the MTBRP can provide a rapid and sensitive method for detection of pulmonary and extra-pulmonary tuberculosis from a wide-variety of smear positive specimen sources.
直接从临床标本中快速检测结核分枝杆菌复合群对于患者治疗至关重要。结核分枝杆菌培养需要数天至数周才能得出结果，因此许多实验室采用快速分子方法来诊断结核病。在美国有两种经美国食品药品监督管理局（FDA）批准的用于检测结核分枝杆菌复合群的分子检测方法，且两种方法均仅批准用于呼吸道标本检测。对于肺外标本中结核分枝杆菌复合群的检测，通常使用实验室自行开发的聚合酶链反应（PCR）方法。在这项研究中，详细介绍了一种实验室自行开发的用于从呼吸道和非呼吸道标本中检测结核分枝杆菌复合群的PCR检测方法（MTBRP）在十年间的检测性能验证及后续确认。该检测方法还可提供有关潜在异烟肼耐药性的信息。将MTBRP PCR检测方法与赛沛Xpert MTB/RIF检测方法在抗酸涂片阳性和涂片阴性标本中的性能进行了比较，并将MTBRP PCR检测方法与抗酸涂片阳性标本的分枝杆菌培养结果进行了比较。使用499份呼吸道标本时，MTBRP检测方法与Xpert MTB/RIF检测方法的相关性为99%。对于867份抗酸杆菌（AFB）涂片阳性的呼吸道和非呼吸道标本，MTBRP PCR检测方法与分枝杆菌培养结果相比，灵敏度为100%，特异性为99.1%。这项研究利用实际临床实验室条件和标本提供了纵向证据，证明像MTBRP这样的实验室自行开发的PCR检测方法可为从多种涂片阳性标本来源中检测肺内和肺外结核病提供快速且灵敏的方法。
