Chronic airway obstruction in post tubercular fibrosis cases: a serious lung function changes

Abstract

Background: Tuberculosis (TB) is a major cause of death worldwide. About two thirds of patients develop impaired pulmonary function after completion of pulmonary tuberculosis treatment. But data is lacking to support this assertion. Objective of the study was to determine the frequency of chronic obstructive pulmonary disease (COPD) in post tubercular fibrosis patients in the hospital. Methods: This is a cross-sectional study which was done at Medinipore Medical College & Hospital in post tubercular fibrosis patients from August 2015 to July 2016. 72 patients who had post tubercular fibrosis were included for spirometry test. Those having a probability of re-activated TB, having history of current or previous smoking or occupational exposure, asthmatics and cases of interstitial lung disease and ischemic heart disease were excluded. Pre- and post-dilator FVC, FEV1 and FEV1/FVC were recorded in each case through simple spirometry. Results: There were 83.3% (n=72) males. Thirty eight (52.7%) were found to have an obstructive ventilatory defect of different degrees: severe/stage III in 63.1% (n=24), moderate/stage II in 21.5%% (n=8) and mild/stage I in 15.7 % (n=6). Ten (13.8) were found to have a restrictive pattern and 12 (16.6%) revealed a mixed obstructive and restrictive pattern. Only 12 patients (16.6%) had normal lung function. Among the 38 patients with obstruction in spirometry, 24 patients (63.2%) were under weight. Conclusions: Chronic obstructive pulmonary disease can occur as one of the chronic complications of pulmonary tuberculosis and the obstructive ventilatory defect appears more common especially in patients with low BMI.