Comparative study of CBNAAT and TB LAMP in a tertiary care hospital, RIMS Ranchi, Jharkhand

Tuberculosis is among the leading contagious illnesses in India and continues to pose a significant public health challenge. It is caused by Mycobacterium tuberculosis and can be potentially fatal. The burden of tuberculosis is relatively high in India. Hence, it is necessary to diagnose and treat tuberculosis as soon as possible, for which a foundation of promising diagnostic modalities is necessary.

Over one year, a cross-sectional investigation was conducted at the Department of Microbiology, RIMS, Ranchi. Two hundred samples from clinically suspected cases of Tuberculosis were evaluated. Ziehl-Neelsen staining, CBNAAT, and TB LAMP were done on all patients. The diagnostic yield and efficacy of both testing methods were compared and evaluated.

ZN staining was positive in 22 out of the 200 samples in our study. The sensitivity and specificity were 58.8 % and 98.7 %, respectively. On conducting TB LAMP testing, it was found that 30 cases were positive for tuberculosis, and two samples were false positives. TB-LAMP demonstrated a sensitivity of 82.35 % and a positivity rate of 98.79 %, with positive and negative predictive values of 93.33 % and 96.4 %, respectively. On the other hand, 34 samples out of 200 were positive for Mycobacterium tuberculosis by CB NAAT.

CBNAAT and TB LAMP are both effective techniques for detecting tuberculosis with comparable results. Our study demonstrated that both methods have nearly equal sensitivity and specificity, and should be recommended for detecting Mycobacterium tuberculosis. TB LAMP can be considered in developing countries like ours in laboratory setups with poor resources.