[An evaluation of fibronectin and IgG in bronchoalveolar lavage fluid of patients with interstitial lung diseases].

FN and IgG levels in both bronchoalveolar lavage fluid and peripheral blood were evaluated in 25 patients with ILD and in 11 normal controls. The results showed: (1) In normal group, the level of lavage fluid FN was similar to that of plasma (P > 0.05). FN levels in BALF of patients with ILD were not only significantly higher than those of controls, but also than those of their own plasma (P < 0.01). However, plasma FN levels showed no remarkable changes in all study groups. (2) IgG levels were significantly increased in BALF of patients with ILD and were somewhat elevated in serum. (3) There were significant correlations between lavage FN or IgG levels and total cell counts in ILD, lavage FN and percentage of neutrophils in IPF, and lavage FN or IgG and percentage of lymphocytes in non-IPF. (4) A highly significant correlation existed between FN and IgG levels in BALF of patients with ILD. These data suggested that FN is significantly increased in patients with ILD. Elevation of lavage FN in ILD may be served as a marker of activity in assessment of alveolitis and elevation of lavage IgG appears to reflect an aspect of activity of humoral immunologic reaction in patients with ILD.