Pulmonary functions' assessment in post-tuberculosis cases by spirometry: Obstructive pattern is predominant and needs cautious evaluation in all treated cases irrespective of symptoms.

Background: Approximately 30%-40% patients suffer with lung function issues in spite of successful treatment outcome; and these problems are less documented routinely.

Methods: Prospective multicentric study conducted during July 2013-June 2017, to find pulmonary function assessment in posttuberculosis (TB) cases irrespective of their symptoms, included 500 cases in symptomatic and asymptomatic group and subjected to inclusion and exclusion criteria. All cases were subjected to spirometry analysis. Statistical analysis was done using Chi-square test.

Results: In spirometry assessment of symptomatic post-TB cases, obstructive pattern was predominant type documented in 42% cases. In spirometry assessment of asymptomatic post-TB cases, obstructive pattern is documented in 32%, mixed pattern in 14%, and normal spirometry is documented in 46% cases. In spirometry assessment in symptomatic and asymptomatic cases, obstructive pattern is documented in 210 cases and 160 cases, respectively (P < 0.00001). Abnormal lung function is documented in 70% and 54% in symptomatic and asymptomatic post-TB cases, respectively (P < 0.00001).

Conclusions: Lung function impairment is known to occur after pulmonary TB irrespective of duration of treatment and outcome of disease. Obstructive lung disease is the predominant lung function impairment in symptomatic cases. Significant number of asymptomatic cases are also having obstructive pattern of lung function in spirometry analysis.