Rahman M M, Rahim M R, Khaled A, Nasir T A, Nasrin F, Hasan M A
Dr Md Mizanur Rahman, Consultant, Molecular Diagnostics, Apollo Hospitals, Dhaka, Bangladesh.
Mymensingh Med J. 2017 Jul;26(3):614-620.
Mycobacteria are subdivided into three groups: the Mycobacterium tuberculosis complex, the non-tuberculous mycobacteria called NTM or MOTT (Mycobacteria Other Than Tuberculosis) and Mycobacterium leprae. Over the past few decades, the incidence of infections caused by NTM has increased world wide. The differentiation of Mycobacterium tuberculosis complex from NTM is of primary importance for infection control and choice of antimicrobial therapy. However, there is so far no report in Bangladesh about the detection of NTM and hence differentiation of MTB and NTM. Neither acid-fast bacilli (AFB) staining nor histopathology can discriminate MTB and NTM. In order to detect and differentiate Mycobacterium tuberculosis complex and NTM we used commercially available LyteStar TB/NTM Real Time PCR kit (Altona Diagnostics, Germany) and analyzed 782 clinical specimens from tuberculosis suspected patients. We have found 49 MTB and 74 NTM positive samples from variety of clinical specimens such as sputum, bronchial lavages, body fluids, tissues, needle aspirates and swabs. Many of the PCR positive specimens were AFB negative on direct microscopic examination thus, indicating strong sensitivity of PCR than AFB staining. This is the first report in the country about detection of NTM and it warrants further elaborate investigation. Moreover, our results showed that multiplex real-time PCR assay is an effective sensitive tool for the rapid identification and differentiation of MTB and NTM directly from clinical specimens.
结核分枝杆菌复合群、称为非结核分枝杆菌（NTM）或非结核性分枝杆菌（MOTT，即除结核分枝杆菌外的其他分枝杆菌）以及麻风分枝杆菌。在过去几十年中，NTM引起的感染发病率在全球范围内有所上升。区分结核分枝杆菌复合群与NTM对于感染控制和抗菌治疗的选择至关重要。然而，孟加拉国迄今尚无关于NTM检测以及因此区分结核分枝杆菌（MTB）和NTM的报告。抗酸杆菌（AFB）染色和组织病理学都无法区分MTB和NTM。为了检测和区分结核分枝杆菌复合群与NTM，我们使用了市售的LyteStar TB/NTM实时荧光定量PCR试剂盒（德国Altona诊断公司），并分析了782份来自疑似结核病患者的临床标本。我们从各种临床标本中，如痰液、支气管灌洗液、体液、组织、针吸物和拭子中，发现了49份MTB阳性样本和74份NTM阳性样本。许多PCR阳性标本在直接显微镜检查时AFB呈阴性，因此表明PCR比AFB染色具有更高的灵敏度。这是该国关于NTM检测的首份报告，值得进一步深入研究。此外，我们的结果表明，多重实时荧光定量PCR检测是一种从临床标本中直接快速鉴定和区分MTB和NTM的有效且灵敏的工具。
