Immunologic studies in bronchoalveolar fluid in a patient with allergic bronchopulmonary aspergillosis

Bronchoalveolar lavage was performed in a patient during an acute stage of allergic bronchopulmonary aspergillosis (ABPA) and repeated 17 mo later during a remission stage and cessation of corticosteroid therapy. Measurement of protein concentrations (albumin, IgG, IgA, and IgM) by laser nephelometry and crossed immunoelectrophoresis indicates that transudation of proteins occurs from the circulation into the lung compartment during the acute stage of ABPA. Furthermore, comparing total Ig concentrations and titers of ELISA IgG, IgA, and IgM antibodies against Aspergillus fumigatus with the corresponding values of serum measurements indicates a preferential local production of IgA antibodies and IgM to a lesser extent. No indications were found for a local production of either IgG, total IgE, or IgE against A. fumigatus. During remission of the ABPA, titers of antibodies in the bronchoalveolar fluid (BAF) decreased to normal levels except IgA against A. fumigatus that remained elevated. The elevated titers of IgA in the BAF and IgE antibodies in the serum against A. fumigatus together with the elevated numbers of granulocytes in the BAF during the remission stage indicate that the immunologic situation is not yet normalized.