Sonographic septation: a predictor of sequelae of tuberculous pleurisy after treatment

Findings in the literature have been quite conflicting with respect to predicting residual pleural thickening (RPT) in tuberculous pleurisy (TP). The aim of this study was to determine which sonographic feature of TP might help in predicting the development of RPT.

Eighty-seven patients with TP were enrolled prospectively. The initial sonographic features were classified as anechoic, homogenously echogenic, complex non-septated and complex septated. The RPT level was measured 12 months after the start of antituberculosis (TB) treatment. Spirometry was performed 6 and 12 months after the start of anti-TB treatment.

A higher odds of an RPT level >10 mm was found in patients with positive TB bacillus culture in pleural fluid (OR, 20.9; 95% CI, 2.2 to 198.0) and a complex septated sonographic pattern (OR, 145.0; 95% CI, 22.3 to 942.3). A complex septated sonographic pattern can predict RPT with a sensitivity of 80%, specificity of 96%, positive predictive value of 84% and negative predictive value of 94%. Patients with an RPT level >10 mm had a lower forced vital capacity than those without (75.4% (9.2%) predicted vs 83.2% (9.5%) predicted, p<0.01)

A complex septated sonographic pattern is a useful sign to predict an RPT level >10 mm 1 year after the start of anti-TB treatment. An RPT level >10 mm is associated with a high probability of decreased lung volumes. Therefore, the initial sonographic feature is beneficial in predicting the sequelae of TP after treatment.