Insights into changing patterns of extrapulmonary tuberculosis in North India

Tuberculosis is one of the dreadful infections and India contributes to substantial burden of TB cases globally. Though majority of cases are pulmonary, extra-pulmonary tuberculosis (EPTB) share significant burden, more in HIV-positive persons. Despite the striking burden, very few studies have been conducted in India and present study was undertaken to determine trends of EPTB at our tertiary care centre. This was a retrospective study conducted over a period of 4 years 3 months. Diagnosis of EPTB was based on suspected clinical features, with positive micobiological evidence with cartridge based nucleic acid amplification test (CBNAAT) with/without microscopy. A total of 10,560 samples (pulmonary and extra-pulmonary) were received during the study period, of which 3972 were extrapulmonary. Of these, a total of 18% were noted to be positive for EPTB. Trend of positivity revealed highest burden in 2018 and a decline was noted over the years, however, rise in cases was noted in 2022. Pleural, meningitis, musculoskeletal, peritoneal and pericardial TB was more common in males, while lymphadenitis was more common in females (p value: <0.0001). Pleural TB (31%) was the most common presentation, followed by lymphadenitis. A gradual decline in lymphadenitis was noted with significantly increasing trend only for musculoskeletal TB. Rifampicin resistance was detected in 7.45% of positive samples, of which the maximum rate of resistance was noted in lymph node aspirates (11.11%), followed by musculoskeletal and pleural samples. The present study showed a gradual decline in positivity of EPTB cases over the years. Younger productive age group with more propensity to transmit infection was the most commonly affected, with pleural TB as the most common presentation. Rare presentations of EPTB also contributed major share. Higher rates of resistance underline requisite to strengthen ongoing programs, to achieve the End TB strategy by 2025.