RESUMO
SETTING: Residual pleural thickness (RPT) is a common complication of tuberculous pleurisy (TP), and the degree of RPT cannot be predicted in advance. OBJECTIVES: To determine whether pleural fluid content has an effect on the development of RPT. DESIGN: Forty-seven patients with TP were enrolled in the study. A set of biochemical tests: lactate dehydrogenase, glucose, total proteins, adenosine deaminase, tumour necrosis factor alpha (TNF-alpha), alpha-1 acid glycoprotein (AAG), alpha-2 macroglobulin, C-reactive protein (CRP), complement 3 and complement 4 were studied in the pleural fluid samples. After 6 months of anti-tuberculosis treatment, patients were re-evaluated for RPT. RPT was defined in a posteroanterior chest radiograph as a pleural space of >2 mm or >10 mm measured in the lower lateral chest at the level of an imaginary horizontal line intersecting the diaphragmatic dome. RESULTS: Seventeen patients (36.17%) had an RPT of <2 mm, 18 (38.29%) had an RPT of 2-10 mm, and 12 (25.53%) had an RPT of >10 mm. TNF-alpha levels were lower in patients with an RPT of <2 mm than in patients with an RPT of 2-10 mm or >10 mm (P < 0.05 and P < 0.01, respectively). The level of TNF-alpha was higher in patients with an RPT of >10 mm compared to the 2-10 mm group (P < 0.05). Meanwhile, pleural fluid glucose, AAG and CRP concentrations were significantly higher in patients with an RPT of >10 mm than in patients with <2 mm RPT (P < 0.05, P < 0.01, and P < 0.05, respectively). CONCLUSION: In TP, the development and degree of RPT are significantly correlated to the glucose, CRP, AAG, and TNF-alpha levels in the pleural fluid.
