DIAGNOSIS OF EXTRAPULMONARY TUBERCULOSIS BY IMMUNOSTAINING OF TISSUES WITH ANTIMPT64 INCLUDING AFB NEGATIVE CASES

Background: Extra Pulmonary Tuberculosis (EPTB) can occur in numerous locations, with the most common sites beingthe lymph nodes, pleura, genitourinary system, bones and joints. Early diagnosis and timely treatment are the most criticalsteps to control the disease, but it is still a challenge due to its paucibacillary nature, vague clinical presentation and siteinvolvement. MPT64 is a unique antigen that has shown high sensitivity and specificity compared to other conventionaltechniques like acid fast stain in its ability to diagnose tuberculosis as well as to differentiate it from non-tuberculousmycobacteria. The objective is to study the utility of Anti-MPT 64 in the diagnosis of extra pulmonary tuberculosis and tocompare the efficacy with Ziehl Neelsen stain. Materials and Methods: The study was done in the Department ofPathology at Narayana Medical College and Hospital, Nellore, Andhra Pradesh, India for a period of 2 years. Total 50 caseswere studied. HandE stain, ZN stain, IHC Anti MPT 64 was done for all cases and data analysis was done. Results: Amongthe 50 cases, more common 34% belonged to 41–50 years age group. More common in males (68%). Most common locationfor EPTB was spine and vertebrae (24%) followed by lymphnode (20%).36% showed Ziehl –Neelsen stain positive and 64%showed ZN staining negative and P value is 0.04 statistically significant. 92% were ANTI - MPT 64 positive and 8% werenegative with a p value of less than 0.05. Conclusion: The efficiency in diagnosing extrapulmonary tuberculosis byimmunohistochemical marker ANTI MPT 64, ways a path to confirm the cases even in AFB negative cases. This highlightsthe importance of ANTI MPT-64 as a potential immunohistochemical marker as India is heading in eradication program forTuberculosis.