Bridging Diagnostic Gaps In Tuberculosis: The Significance Of Is6110 And Mpb64 In Pulmonary And Extrapulmonary Tb, And The Role Of Nucleic Acid Amplification And Multidimensional Testing For Global Health And Wellbeing

Abstract

The causative agent of tuberculosis (TB) is Mycobacterium tuberculosis, one of the global health concerns with morbidity and mortality. TB presents in two forms; pulmonary tuberculosis (PTB) affects the lungs, and extrapulmonary tuberculosis  (EPTB) affects organs other than the lungs. The study was carried out at DNA Labs, DLCAS, Dehradun, Uttarakhand, where 85 clinical materials, including broncho alveolar lavage (BAL), cerebrospinal fluid (CSF), pus, and biopsies were studied. ZN staining and PCR targeting IS6110 and mpb64 genes were performed as per standard protocol. Amplification of M. tuberculosis PCR assays included standard protocols. Fragment of DNA were analyzed using agarose gel electrophoresis. ZN staining detected AFB in 9.4% of 85 specimens. IS6110 was more frequently detected than MPB64 (27 IS6110 positive vs. 13 MPB64 positive by PCR). The performance of ZN was good for PTB but moderate for EPTB and low bacterial loads. PCR was more sensitive and specific and showed that the gene markers varied between specimen types. The EPTB and negative or mixed results of initial tests posed particular diagnostic challenges. These findings highlight the need for a multimodal diagnostic approach integrating ZN staining and higher-tier molecular methods, such as nested PCR. Patients showed gender- and age-based variations in tuberculosis detection, with specific symptoms including abscesses or meningitis having higher odds of positive results. With various diagnostic tests failing to detect all forms of malignant diseases, the new study underscores the importance of employing diverse diagnostic methods. Failure to apply these additional tests may lead to an incomplete diagnosis of tuberculosis.