BRONCHOALVEOLAR LAVAGE IN EXTRINSIC ALLERGIC ALVEOLITIS - EFFECT OF TIME ELAPSED SINCE ANTIGEN EXPOSURE

The aim of the present study was to investigate whether bronchoalveola r lavage (BAL) cell profile and immunoglobulin levels from patients wi th extrinsic allergic alveolitis (EAA) were related to the time elapse d between last antigen exposure and BAL. For this purpose, an analysis was performed of BAL fluid (BALF) obtained from 59 nonsmoking EAA pat ients at various time-points after termination of antigen exposure and BAL. BALF early after antigen provocation (group 1: <24 h) contained high absolute and relative numbers of lymphocytes, neutrophils, eosino phils and mast cells, and a low relative number of alveolar macrophage s. When obtained after recent antigen exposure (group 2: 2-7 days), BA LF showed high numbers of lymphocytes, plasma cells and mast cells, an d high levels of immunoglobulins M, G and A (IgM, IgG and IgA). In BAL obtained one week or more after the final antigen exposure, (Group 3: 8-30 days; Group 4: 1-12 months) the distribution of all constituents showed a tendency to return to normal values, with the exception of t he lymphocytes. These results demonstrate that BAL cell profile and im munoglobulin levels in EAA are highly dependent on the time-point at w hich the material is obtained in relation to the last exposure to the causative antigen.