喀麦隆结核疑似人群中非结核分枝杆菌的特征。

Profile of non-tuberculous mycobacteria amongst tuberculosis presumptive people in Cameroon.

机构信息

Mycobacteriology Unit, National Tuberculosis Reference Laboratory, Centre Pasteur du Cameroun, Yaounde, Cameroon.

Department of Microbiology, University of Yaounde I, Yaounde, Cameroon.

出版信息

BMC Microbiol. 2024 Mar 26;24(1):100. doi: 10.1186/s12866-024-03256-x.

DOI:10.1186/s12866-024-03256-x

PMID:38532357

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10964636/

Abstract

BACKGROUND

Cameroon is a tuberculosis (TB) burden country with a 12% positivity among TB presumptive cases. Of the presumptive cases with a negative TB test, some are infected with Non-tuberculous Mycobacteria (NTM). However, the diagnosis of NTM infections remains difficult due to the lack of tools in many laboratories, particularly in resource limited laboratories and remote setting. The present study was undertaken to determine NTM profile and associated comorbidities among TB presumptive people.

METHODS

A retrospective study was conducted from December 2018 to December 2019 in the Tuberculosis-National Reference Laboratory (TB-NRL) for Bacteriological analysis of samples and Jamot Hospital of Yaounde (JHY) for clinical evaluation of confirmed NTM patients. We included in this study data of 5267 TB presumptive people previously diagnosed using three consecutive samples and having culture and SD Bioline results with or without Microscopy and reverse hybridization-based Line Probe Assay(LPA) results. The data on co-morbidities or history of people infected with NTM were then collected from the three participants with available clinical data.

RESULTS

We collected data of 5267 presumptive TB people. Among them, 3436 (65.24%), have a positive culture with 3200 (60.75%) isolates belong to Mycobacterium tuberculosis Complex (MBTC) and 236 (4.48%) to NTM. Our results showed that, 123 (52.11%) NTM were isolated from people with negative microscopy and 113 (47.88%) from people with positive microscopy. Among the 236 NTM, 108 (45.8%) isolates were identified using LPA. M. fortuitum was the most represented species (32.41%) followed by M. intracellulare (19.44%). Sputum had the highest proportion of NTM (56%), followed by bronchial aspirations (31%). The extra-pulmonary samples presented lower proportions of isolates compared to pulmonary samples. Some patients affected with NTM presented comorbidities as HIV infection, Pulmonary tuberculosis, Type 2 diabetes, Chronic bronchitis and Alveolar pneumonia.

CONCLUSIONS

Our study showed the presence of NTM strains among presumptive TB people with a predominance of M. fortuitum and M. intracellulare. It is important to implement a surveillance system of NTM in TB burden country and also to develop a point-of-care test for NTM identification in limited-resource settings.

摘要

背景

喀麦隆是一个结核病（TB）负担沉重的国家，TB 疑似病例中阳性率为 12%。在 TB 检测阴性的疑似病例中，有一些是感染了非结核分枝杆菌（NTM）。然而，由于许多实验室缺乏工具，特别是在资源有限的实验室和偏远地区，NTM 感染的诊断仍然很困难。本研究旨在确定 TB 疑似人群中 NTM 谱及其相关合并症。

方法

本研究为回顾性研究，于 2018 年 12 月至 2019 年 12 月在喀麦隆雅温得结核病国家参考实验室（TB-NRL）进行细菌学分析，在雅温得若莫医院（JHY）对确诊的 NTM 患者进行临床评估。我们纳入了这项研究的数据，这些数据来自于 5267 名之前使用连续三个样本诊断为 TB 的疑似患者，这些患者的培养和 SD Bioline 结果有或没有显微镜和反向杂交线探针分析（LPA）结果。然后，从三名有临床数据的参与者中收集了有关感染 NTM 人群的合并症或病史的数据。

结果

我们收集了 5267 名疑似 TB 患者的数据。其中，3436 名（65.24%）的培养结果呈阳性，3200 名（60.75%）的培养物属于结核分枝杆菌复合群（MBTC），236 名（4.48%）属于 NTM。我们的结果表明，123 名（52.11%）NTM 是从显微镜阴性的人群中分离出来的，113 名（47.88%）是从显微镜阳性的人群中分离出来的。在 236 株 NTM 中，108 株（45.8%）使用 LPA 进行了鉴定。脓肿分枝杆菌是最主要的代表种（32.41%），其次是胞内分枝杆菌（19.44%）。痰标本中 NTM 的比例最高（56%），其次是支气管抽吸物（31%）。与肺标本相比，肺外标本的分离率较低。一些患有 NTM 的患者存在合并症，如 HIV 感染、肺结核、2 型糖尿病、慢性支气管炎和肺泡肺炎。