Bronchoalveolar lavage fibronectin in patients with sarcoidosis: correlation to hyaluronan and disease activity

Bronchoalveolar lavage was performed in 51 patients with sarcoidosis and in 21 healthy nonsmokers. The concentration of fibronectin was significantly higher (p less than 0.001) in lavage fluid from sarcoid patients (median 267 micrograms.l-1) than in that of controls (46 micrograms.l-1). Furthermore, a significantly higher concentration of fibronectin was found in patients with active disease than in those in whom the disease was inactive (p less than 0.001). In a six month follow-up perspective, patients with a progressive disease course had significantly higher levels of fibronectin than those who had a stable or regressive disorder (p less than 0.01). Correspondingly, lavage hyaluronan was higher (p less than 0.001) in sarcoid patients (55 micrograms.l-1) than in controls (9 micrograms.l-1) and higher (p less than 0.01) in those with active than in those with inactive disease. Patients with progressive disease had higher (p less than 0.01) concentrations of hyaluronan than those in whom the disease was stable. A significant correlation was found between lavage fibronectin levels and hyaluronan (r = 0.81, p less than 0.001). The percentage of mast cells was also higher in patients with active than in those with inactive disease (p less than 0.01) and higher in progressive than in stable sarcoidosis (p less than 0.001). Ten out of 10 patients with progressive disease had mast cells greater than or equal to 0.5%, hyaluronan greater than or equal to 50 micrograms.l-1 and fibronectin greater than or equal to 350 micrograms.l-1 compared to eight out of 41 patients with stable or regressive disease