The diagnostic concordance between micro real-time PCR and Lowenstein Jensen (LJ) media assays for pulmonary tuberculosis detection with associated clinical characteristics

Abstract

Tuberculosis (TB) is an infectious disease that can affect various parts of the body, with lung infections being the most common cause. In this study, drug susceptibility testing (DST) using LJ media was compared to Truenat testing to detect rifampicin resistance in sputum smear-positive cases with related clinical characteristics. The Vedantaa Institute of Medical Sciences conducted a laboratory-based study from July 2023 to December 2023, enrolling 102 clinical isolates. Sputum smears with acid-fast bacilli were cultured in LJ medium, isolated, and grown with rifampicin for resistance observation and a correlation with Truenat.The study found that individuals aged 21–30 had the highest prevalence of TB. The highest detection ratio was shown in the Below Poverty Line (BPL) at 84.2%, and Rifampicin (RIF) resistance was detected at 75%. A TB positive ratio of 68.4% were found to be both alcoholic and smoker population and 42.1% were found to have asthma and liver disease, no Rifampicin (RIF) resistance was detected in both the population. In HIV patients 50% RIF resistance was detected. MTB coinfections were observed in 68.4% of pneumonia patients. The LJ culture test had 95% sensitivity and 100% specificity for MTB detection, while the Truenat test had 100% sensitivity and 100% specificity for both MTB testing and MTB/RIF resistance detection.Demographic, clinical, and social variables, including alcoholics and smokers, asthma and liver disease, hypertension, diabetes, and co-infection with pneumonia, were the main factors for pulmonary tuberculosis patients. Micro-real-time PCR has higher clinical sensitivity for MTB detection, while conventional tests predict rifampicin resistance.