LAUSR

Dear Editor, It is worthy to comment on the interesting study by Patil et al. on the pulmonary functions’ assessment in post‐tuberculosis (TB) cases in India.[1] On employing spirometry, the authors measured various components of pulmonary function tests (PFTs). They found that, in symptomatic post‐TB cases, obstructive pattern was the predominant type documented in 42% of cases. However, in asymptomatic post‐TB cases, obstructive pattern was documented in 32%, mixed pattern in 14%, and normal spirometry in 46% cases. In symptomatic and asymptomatic cases, obstructive pattern was documented in 210 cases and 160 cases, respectively (P < 0.00001). Abnormal lung function was documented in 70% and 54% in symptomatic and asymptomatic post‐TB cases, respectively (P < 0.00001).[1] I presume that such results ought to be cautiously taking owing to the presence of the following methodological limitation. It is obvious that reference values of PFT components are affected by many factors including regional, environmental, and anthropometric factors.[2] To my knowledge, population in India is polygenetic and it is an astonishing amalgamation of various cultures and ethnicities. The author did not consider the ethnic groups of the studied cohort. This is an important point as noticeable differences in spirometric reference values among different ethnic groups do exist.[3] Despite the aforementioned limitation, the study results have clinical implications in the management of TB patients.