Yamouni Ferroudja, Henniche Fatma Zohra, Ifticene Malika, Chabani Madjid, Bensersa Doria, Ouadah Nour El Houda, Nihad Mansuer, Zerouki Ali
Laboratoire de microbiologie, Hôpital central de l'armée « Mohamed Seghir Nekkache », Alger, Algérie.
Laboratoire national de référence de la tuberculose et de la surveillance de la résistance, Institut Pasteur d'Alger, Algérie.
Med Trop Sante Int. 2024 Jun 12;4(2). doi: 10.48327/mtsi.v4i2.2024.301. eCollection 2024 Jun 30.
Retrospective study carried out over a period of five years, from May 2017 to June 2022 at the microbiology laboratory of the Central army Hospital Mohamed Seghir Nekkache, Algiers (Algeria). The pulmonary and extrapulmonary clinical specimens were collected, cultivated, tested by GX PCR and direct examination by Ziehl-Neelsen staining. The study of sensitivity to antituberculosis drugs was performed according to the proportion method on liquid medium Bactec MGIT 960 (or on solid medium Lowenstein-Jensen at the Algerian Pasteur Institute).
310 samples were included in the final analysis of the study, of which 156 were of pulmonary origin and 154 of extrapulmonary origin. complex (MTBC) was detected in 95 samples from 88 tuberculosis patients (sex ratio 2,03 and middle age 37 years) with 49 cases of pulmonary tuberculosis and 39 cases of extra-pulmonary tuberculosis. For 2 cases, the GX was positive while the culture was negative and for 11 cases, the GX was negative while the culture was positive. Thus, in our study and compared to culture, GX showed an overall sensitivity of 88.2%, a specificity of 98.6%, a positive predictive value (PPV) of 96.4% and a negative predictive value (NPV) of 95.2%. The analysis of the data according to the type of samples, the sensitivity, specificity, PPV and NPV of GX for the pulmonary and extrapulmonary samples were 96.3% vs. 77.0%, 98.0% vs. 99.1%, 96.2% vs. 96.5% and 98.0% vs. 92.7% respectively. The sensitivity of GX for disco-vertebral, lymph node, meningeal and pleural tuberculosis were 100%, 90.0%, 71.4% and 57.1% respectively. The sensitivity of GX for pulmonary tuberculosis compared to microscopy was 96% vs. 68%. The comparison of the results of detection of resistance to rifampicin by GX and by phenotypic methods showed perfect agreement.
A good sensitivity of GX compared to microscopy was revealed. The GX is a useful tool for the diagnosis of pulmonary tuberculosis, especially in smear-negative cases. The sensitivity of GX in extrapulmonary tuberculosis varied depending on the location of the infection. A negative result by GX does not exclude tuberculosis and cases of resistance to RIF detected by GX must be confirmed by phenotypic method.
1）评估GeneXpert MTB/RIF（GX）检测在肺结核和肺外结核诊断中相对于培养法的贡献。2）比较GX获得的利福平耐药结果与表型敏感性试验结果。
回顾性研究，于2017年5月至2022年6月在阿尔及尔（阿尔及利亚）中央陆军医院穆罕默德·塞吉尔·内卡谢微生物实验室进行，为期五年。收集肺和肺外临床标本，进行培养、GX PCR检测以及齐-尼氏染色直接检查。根据比例法在液体培养基Bactec MGIT 960（或在阿尔及利亚巴斯德研究所的固体培养基罗氏培养基）上进行抗结核药物敏感性研究。
310份样本纳入研究最终分析，其中156份来自肺部，154份来自肺外。在88例结核病患者的95份样本中检测到结核分枝杆菌复合群（MTBC）（性别比2.03，中位年龄37岁），其中49例为肺结核，39例为肺外结核。2例样本GX检测为阳性而培养为阴性，11例样本GX检测为阴性而培养为阳性。因此，在我们的研究中，与培养法相比，GX的总体敏感性为88.2%，特异性为98.6%，阳性预测值（PPV）为96.4%，阴性预测值（NPV）为95.2%。根据样本类型分析数据，GX对肺和肺外样本的敏感性、特异性、PPV和NPV分别为96.3%对77.0%、98.0%对99.1%、96.2%对96.5%和98.0%对92.7%。GX对椎间盘、淋巴结、脑膜和胸膜结核的敏感性分别为100%、90.0%、71.4%和57.1%。GX对肺结核相对于显微镜检查的敏感性为96%对68%。GX和表型方法检测利福平耐药结果的比较显示完全一致。
揭示了GX相对于显微镜检查具有良好的敏感性。GX是诊断肺结核的有用工具，尤其是在涂片阴性的病例中。GX在肺外结核中的敏感性因感染部位而异。GX检测结果为阴性不能排除结核病，且GX检测到的利福平耐药病例必须通过表型方法进行确认。
