transforming-growth-factor-beta and Empyema

Clubbing was first described by Hippocrates more than 2.500 years ago. It may be seen alone or as part of an entity called hypertrophic osteoarthropathy which include periostitis, arthritis and sometimes thickening and edema of the skin around the affected joints. Pulmonary diseases such as cancer, abscess, empyema, bronchiectasis and cystic fibrosis are the major diseases known to be associate with hypertrophic osteoarthropathy. Digestive tract cancer, cyanogenic congenital heart disease are well known association. Many theories have attempted to explain the appearance of this sign but few have persisted. In this article, we review characteristics, relation with etiology and the basis of the pathophysiology of hypertrophic osteoarthropathy and particularly of clubbing.

Topics: Bronchiectasis; Causality; Cystic Fibrosis; Digestive System Neoplasms; Empyema; Ferritins; Heart Defects, Congenital; Humans; Lung Abscess; Lung Neoplasms; Osteoarthropathy, Secondary Hypertrophic; Platelet-Derived Growth Factor; Prostaglandins; Transforming Growth Factor beta

Transforming growth factor-beta1 (TGF-beta1) is a growth factor that is implicated in fibrosis of many organs. The purpose of this study was to determine the sequential levels of TGF-beta1 in the pleural fluid of rabbits that had undergone empyema induction, as fibrosis of the pleural space develops. Thirty-seven rabbits underwent empyema induction. Rabbits were sacrificed on Days 1, 2, 3, 4, 5, 6, and 8. Pleural fluid and viscera pleura specimens were collected at autopsy. TGF-beta1 levels were measured in pleural fluid using a commercially available ELISA kit, and pathologic specimens were scored for evidence of fibrosis (pleural thickness and number of fibroblasts). The median levels of pleural fluid TGF-beta1 increased from 8,100 pg/ml (Days 1 and 2) to 39,600 pg/ml (Day 8). Pleural fluid TGF-beta1 levels closely correlated with microscopic pleural thickness (r = 0.7, p < 0.001) and number of fibroblasts present in the visceral pleura (r = 0.68, p < 0.001). The first increase in pleural fluid levels of TGF-beta1 (Day 3) occurred before the increase in pleural thickness (Day 4) and before the increase in number of fibroblasts (Day 4). In conclusion, pleural fluid levels of TGF-beta1 rise in experimental empyema as pleural fibrosis develops. The rise in empyemic pleural fluid TGF-beta1 levels correlates with markers of pleural space fibrosis.

Topics: Analysis of Variance; Animals; Biomarkers; Biopsy, Needle; Disease Models, Animal; Empyema; Female; Fibrosis; Immunohistochemistry; Male; Pleural Diseases; Pleural Effusion; Probability; Rabbits; Sensitivity and Specificity; Transforming Growth Factor beta; Transforming Growth Factor beta1