BACKGROUND: The aim of our study was to identify predictive factors for the development of residual pleural thickening (RPT) in patients with tuberculous pleurisy (TP). METHODS: A retrospective study of patients with pleural tuberculosis. The clinical and radiological characteristics, and measurements of microbiological and biochemical parameters or markers such as adenosine deaminase (ADA), interferon-gamma (IFN-gamma) and vascular endothelial growth factor (VEGF) in pleural fluid were studied. RESULTS: Thirty one patients (24 male and 7 female) with a mean age of 55.9 years were studied. There were 25 (80.6%) patients with RPT > 2 mm and 6 (19.4%) patients without RPT. Ten patients (32.2%) had RPT > or = 10 mm. The rate of pleural thickening was less in small effusions (p<0.05). IFN-gamma was higher in patients with RPT > or = 10 mm (p < 0.05) in comparison with those with RPT < 10 mm. CONCLUSIONS: Pleural fluid IFN-gamma may deserve further investigation in order to build up preventive and therapeutic strategies against RPT and its clinical complications.