Predictors of radiological sequelae of pulmonary tuberculosis

In patients with pulmonary tuberculosis, clinical factors that are associated with poor radiological outcome have not been adequately addressed in the medical literature. The aim of this study was to explore some of these factors in patients admitted to a large chest hospital in Saudi Arabia with pulmonary tuberculosis.

Chest radiographs of 1,080 patients with pulmonary tuberculosis were reviewed. Post-treatment residual changes were classified from 1 to 5 according to the severity of these changes. Data analysis was done by tabulating these classes against different variables that were likely to influence the final radiological appearance at the end of the treatment period.

Near-complete or complete clearance of chest radiography (Class 1) was seen in 43.5% of patients <20 years old compared to 30.3% in patients > 40 years old (p < 0.05). The latter group also had significantly higher rate of pleural thickening (9.4% vs. 3.6%), higher rate of fibronodular densities (24.9% vs. 19.5%) and higher rate of persistent cavitation (18.3% vs. 11.9%). Females had a significantly lower rate of chest radiography clearance (30.5%)) than males (41.4%). Patients with a duration of respiratory symptoms of <4 weeks had 45.2% Class 1 radiography compared to 24.6% for those with longer duration of symptoms (> 8 weeks). Chest radiography clearance was more frequent (51.6%)) in patients with good compliance with drug therapy compared to those with poor compliance (18.8%). Persistent cavitation (Class 5) was seen in 30.4% of cases with a past history of tuberculosis and in only 14% of cases with no such history.

Old age, female gender, long duration of symptoms (delayed diagnosis), poor compliance with treatment and positive history of tuberculosis were associated with poor radiological outcome.