喀麦隆滨海地区肺结核患者复杂菌株的遗传多样性初步研究。

A pilot study on the genetic diversity of complex strains from tuberculosis patients in the Littoral region of Cameroon.

作者信息

Thumamo Pokam Benjamin D, Yeboah-Manu D, Teyim P M, Guemdjom P W, Wabo B, Fankep A B D, Okonu R E, Asuquo Anne E

机构信息

Department of Medical Laboratory Science, University of Buea, Cameroon.

Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra, Ghana.

出版信息

J Clin Tuberc Other Mycobact Dis. 2020 Sep 1;21:100182. doi: 10.1016/j.jctube.2020.100182. eCollection 2020 Dec.

DOI:10.1016/j.jctube.2020.100182

PMID:32964145

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7490731/

Abstract

BACKGROUND

The re-emergence of tuberculosis (TB) worldwide, compounded by multi-drug resistance (MDR) of the causative agents constitutes a major challenge to the management of the disease. Rapid diagnosis and accurate strain identification are pivotal to the control of the disease. This pilot study investigated the genetic diversity of complex (MTBC) strains from TB patients in the Littoral region of Cameroon as well as their resistance to rifampicin (RIF).

PATIENTS AND METHODS

This was a cross sectional hospital-based study carried out between January and December 2017 and including 158 isolates from sputum smear positive individuals [105 (66.5%) males and 53 (33.5%) females]. Sputum samples were tested using Xpert MTB/RIF, followed by culture on Lowenstein-Jensen medium. Isolates were further subjected to molecular characterization using typing, deletion analysis and spoligotyping.

RESULTS

Thirteen (8.8%) of the 147 isolates with susceptibility results available were resistant to RIF. Drug resistance occurred in 5/50 (10%) female compared to 8/97 (8.2%) male (OR, 0.81; 0.25-2.62; p = 0.764), and there was no significant difference across the age ranges (p = 0.448). On the other hand, RIF resistance was associated (OR, 0.18, 95%CI, 0.05-0.69; p = 0.023) with previously treated patients [(4/14 (28.6%)] compared to new ones [9/133 (6.8%)]. The 150 identified lineages included among others 54 (36%) Cameroon, 18 (12%) UgandaI, 32 (21.3%) Haarlem, 17 (11.3%) Ghana, 9(6%) West African 1, 7(4.7%) Delhi/CAS, 4 (2.7%) LAM and 3 (2%) UgandaII. Of the 150 isolates, the major cluster was the Cameroon SIT 61, with 43(28.7%) isolates. Six (35.3%) of the 17 UgandaI sub-lineage were RIF resistant (OR, 9.58; 95%CI, 2.74-33.55, p = 0.001).

CONCLUSION

The cosmopolitan Littoral region presents with a wide (MTB) strains diversity and the UgandaI sub-lineage likely associated with RIF resistance. Understanding the spread of this clade through surveillance will enhance TB control in the region.

摘要

背景

全球结核病再度出现，加之病原体的多重耐药性，对该疾病的管理构成了重大挑战。快速诊断和准确的菌株鉴定对于疾病控制至关重要。本试点研究调查了喀麦隆滨海地区结核病患者中结核分枝杆菌复合群（MTBC）菌株的遗传多样性及其对利福平（RIF）的耐药性。

患者与方法

这是一项于2017年1月至12月在医院开展的横断面研究，纳入了158株来自痰涂片阳性个体的分离株[105名（66.5%）男性和53名（33.5%）女性]。痰标本采用Xpert MTB/RIF检测，随后在罗-琴培养基上培养。分离株进一步通过基因分型、缺失分析和间隔寡核苷酸分型进行分子特征分析。

结果

在147株有药敏结果的分离株中，13株（8.8%）对RIF耐药。女性耐药率为5/50（10%），男性为8/97（8.2%）（比值比，0.81；0.25 - 2.62；p = 0.764），各年龄组之间无显著差异（p = 0.448）。另一方面，RIF耐药与既往治疗患者相关（比值比，0.18，95%可信区间，0.05 - 0.69；p = 0.023），既往治疗患者中4/14（28.6%）耐药，新发病患者中9/133（6.8%）耐药。鉴定出的150个谱系包括54个（36%）喀麦隆谱系、18个（12%）乌干达I谱系、32个（21.3%）哈勒姆谱系、17个（11.3%）加纳谱系、9个（6%）西非1谱系、7个（4.7%）德里/CAS谱系、4个（2.7%）LAM谱系和3个（2%）乌干达II谱系。在150株分离株中，主要聚类是喀麦隆SIT 61，有43株（28.7%）。17株乌干达I亚谱系中有6株（35.3%）对RIF耐药（比值比，9.58；95%可信区间，2.74 - 33.55，p = 0.001）。