The efficacy of targeted sequencing technology in diagnosing tuberculosis using extrapulmonary tissue and body fluid specimens

Wang Xianlei; Liu Ming; Xie Jiong; Zhang Huan

doi:10.3969/j.issn.1671-6450.2026.01.010

Abstract：Objective To evaluate the diagnostic efficacy of targeted sequencing technology for tuberculosis in tissues and body fluids.Methods The positive detection rates of Mycobacterium tuberculosis(TB)using four traditional methods-seminested real-time fluorescence quantitative PCR(GeneXpert),fluorescent probe-based nucleic acid detection(TB-DNA),Mycobacterium tuberculosis culture,and acid-fast staining-in airway and extrapulmonary specimens were statisti-cally analyzed,and pairwise results were assessed for consistency.The positive rates of tNGS versus the four traditional meth-ods were compared across groups and subgroups in extrapulmonary specimens.ROC curves were plotted based on final diag-noses to evaluate the diagnostic performance of tNGS for proliferative pulmonary tuberculosis and extrapulmonary tuberculosis.Results Compared with TB-DNA,Mycobacterium tuberculosis culture,and acid-fast staining,GeneXpert dem-onstrated the highest positive rates in both extrapulmonary and airway specimen groups(airway:25.0％,extrapulmonary:32.0％).Pairwise comparisons of identical methods between groups showed poor consistency among the four traditional meth-ods(Kappa＜0.40).Among the five detection methods in extrapulmonary specimens,tNGS achieved a 76.0％positive rate(92/121),with tissue subgroups showing 73.0％(54/74)and body fluid subgroups 80.9％(38/47)—significantly higher than other methods within each subgroup(P＜0.001).No significant difference was observed between tissue and body fluid sub-groups using tNGS(P＞0.05).Based on the final diagnostic results,among the five methods,tNGS demonstrated the strongest comprehensive diagnostic performance in extrapulmonary specimens,with an AUC of 0.771 and a sensitivity of 83.6％,along with a Youden index of 54.2％—significantly higher than other methods.The specificity of tNGS reached 70.6％,while its positive predictive value was as high as 94.6％.Conclusion Among conventional methodologies,GeneXpert exhibits the highest positivity rate across various specimen types and demonstrates optimal consistency.The tNGS method outperformed traditional approaches in the comprehensive diagnosis of proliferative pulmonary tuberculosis and extrapulmonary tuberculosis,effectively reducing diagnostic discrepancies caused by variations in lesion locations and morphological characteristics.