Levels of transferrin in bronchoalveolar lavage fluid in sarcoidosis.

There has been only one report showing high levels of transferrin (Tf) in bronchoalveolar lavage fluid (BALF) in patients with sarcoidosis. This study was designed to assess the levels of Tf in both BALF and serum and to examine the relationship between the levels of Tf and other disease markers in sarcoidosis. Subjects were 64 sarcoidosis and 10 healthy controls. Tf in BALF and serum was measured by nephelometric assay. Median Tf levels in BALF from sarcoidosis was 0.70 (range, 0.00-3.97) mg/dl, which was significantly higher compared with controls (0.36 (range, 0.00-1.02) mg/dl; p = 0.005). In contrast, median Tf levels in serum from sarcoidosis was 258 (range, 171- 383) mg/dl, which was significantly lower compared with controls (322 (range, 234-356) mg/dl; p = 0.003). Tf levels in BALF were significantly correlated with both the percentage of lymphocytes (r = 0.617, p = 0.001) and serum angiotensin-converting enzyme activity (r = 0.363, p = 0.003) and serum soluble interleukin-2 receptor (r = 0.450, p = 0.001) in sarcoidosis. Levels of Tf in BALF from patients with sarcoidosis were not influenced by smoking status. The levels of Tf in sarcoidosis are high in BALF, but low in serum. Increased levels of Tf in BALF may reflect the disease activity.