Pulmonary Tuberculous Lesions: An Autopsy Study in Central Kerala, India.

Introduction: Tuberculosis (TB) is a leading cause of mortality and morbidity in India. While India is moving towards ending TB, estimating the TB burden is still a challenge. This study aims to assess the prevalence of pathologically active TB in the lungs of deceased persons undergoing autopsy.

Methods: The study group consisted of all cases undergoing autopsy during the study period (May 2021-October 2022). Tissue bits from the apex of both lungs were collected during the autopsy. Gross pathological examination of both lungs and microscopy of tissue bits were done. Proportion and 95% confidence intervals were estimated for the prevalence of pathologically active TB. A chi-square test was applied to determine the factors associated with pathologically active TB.

Results: A total of 311 subjects were included in the study, of which 244 were male (78%), and the mean age was 51.32 (±15.9) years. The most frequent cause of autopsy was road traffic accidents, followed by death due to hanging. The proportion of pathologically active TB was estimated to be 2.89% (95%CI: 1.53%-5.41%). Nucleic Acid Amplification Test (NAAT) testing was done for a subset of 51 specimens, in which Mycobacterium tuberculosis was detected in only one case (1.96% (95%CI: 0.05%-10.45%)). Factors associated with the detection of lesions of TB were smoking, alcohol use, and prior history of TB.