Armauer Hansen Research Institute, Addis Ababa, Ethiopia.
Department of Medical Laboratory Science, Addis Ababa University, Addis Ababa, Ethiopia.
PLoS One. 2022 Mar 31;17(3):e0265499. doi: 10.1371/journal.pone.0265499. eCollection 2022.
Tuberculosis lymphadenitis (TBLN) diagnosis is often challenging in most resource poor settings. Often cytopathologic diagnosis of TBLN suspected patients is inconclusive impeding timely clinical management of TBLN suspected patients, further exposing suspected patients either for unnecessary use of antibiotics or empirical treatment. This may lead to inappropriate treatment outcome or more suffering of suspected patients from the disease. In this study, an integrated diagnostic approach has been evaluated to elucidate its utility in the identification of TBLN suspected patients.
A cross-sectional study was conducted on 96 clinically diagnosed TBLN suspected patients, where fine needle aspirate (FNA) samples were collected at the time of diagnosis. FNA cytology, Ziehl-Neelsen (ZN), Auramine O (AO) staining, GeneXpert MTB/RIF and Real time PCR (RT-PCR) were performed on concentrated FNA samples. Considering culture as a gold standard, the sensitivity, specificity, positive and negative predictive values were calculated. Cohen's Kappa value was used to measure interrater variability and level of agreement and a P-value of <0.05 was considered as statistically significant.
Out of the 96 FNA sample, 12 (12.5%) were identified to have Mycobacterium tuberculosis (Mtb) using ZN staining, 27 (28.1%) using AO staining, 51 (53.2%) using FNAC, 43 (44.7%) using GeneXpert MTB/RIF, 51 (53.1%) using Real time PCR (RT-PCR) and 36 (37.5%) using Lowenstein-Jensen (LJ) culture. Compared to LJ culture, the sensitivities of GeneXpert MTB/RIF, RT-PCR, and FNAC were 91.7%, 97.2%, and 97.2%, respectively and the specificities were 83.3%, 73.3%, and 68.3%, respectively. GeneXpert MTB/RIF and RT-PCR when combined with FNAC detected 61 (63.5%) cases as having Mtb, and the sensitivity and specificity was 100% and 58.3%, respectively.
FNA cytology and RT-PCR detected more TBLN cases compared to other Mtb detection tools and the detection sensitivity even improved when FNA cytology was combined with GeneXpert MTB/RIF, performed on concentrated FNA sample, suggesting the combined tests as an alternative approach for improved diagnosis of TBLN.
在大多数资源匮乏的环境中，结核病性淋巴结炎（TBLN）的诊断通常具有挑战性。通常，对疑似 TBLN 患者进行细胞病理学诊断并不明确，这阻碍了对疑似 TBLN 患者的及时临床管理，使疑似患者面临不必要的抗生素使用或经验性治疗。这可能导致治疗不当或疑似患者因疾病而遭受更多痛苦。在这项研究中，评估了一种综合诊断方法，以阐明其在识别疑似 TBLN 患者中的效用。
对 96 例临床诊断为 TBLN 疑似患者进行了横断面研究，在诊断时采集细针抽吸（FNA）样本。对浓缩的 FNA 样本进行了 FNA 细胞学、Ziehl-Neelsen（ZN）、Auramine O（AO）染色、GeneXpert MTB/RIF 和实时 PCR（RT-PCR）检测。以培养为金标准，计算了灵敏度、特异性、阳性和阴性预测值。使用 Cohen's Kappa 值来衡量评分者间的变异性和一致性水平，P 值<0.05 被认为具有统计学意义。
在 96 例 FNA 样本中，12 例（12.5%）ZN 染色、27 例（28.1%）AO 染色、51 例（53.2%）FNAC、43 例（44.7%）GeneXpert MTB/RIF、51 例（53.1%）RT-PCR 和 36 例（37.5%）低氏（LJ）培养检测到分枝杆菌结核（Mtb）。与 LJ 培养相比，GeneXpert MTB/RIF、RT-PCR 和 FNAC 的灵敏度分别为 91.7%、97.2%和 97.2%，特异性分别为 83.3%、73.3%和 68.3%。GeneXpert MTB/RIF 和 RT-PCR 与 FNAC 联合检测到 61 例（63.5%）Mtb 阳性病例，灵敏度和特异性分别为 100%和 58.3%。
与其他 Mtb 检测工具相比，FNA 细胞学和 RT-PCR 检测到更多的 TBLN 病例，当 FNA 细胞学与浓缩的 FNA 样本上的 GeneXpert MTB/RIF 联合检测时，检测灵敏度甚至更高，这表明联合检测是提高 TBLN 诊断的一种替代方法。
