Immunologic studies in patients with recurrent bronchopulmonary infections.

In view of the known association of several different immune deficiency disorders with infections of the respiratory tract, a number of immunologic parameters were investigated in 15 patients with recurrent brochopulmonary infections. The patients' neutrophils all demonstrated normal intracellular killing of Staphylococcus aureus, and responded normally to chemotactic stimuli. Although assays of complement 3c were normal in all patients' sera, defective total hemolytic complement activity was consistently shown in 1 patinets manifested elevated serum immunoglobulin concentrations. Severe alpha1 -antitrypsin deficiency (Pi ZZ phenotype) was discovered in 1 patient. Three patients displayed cutaneous anergy to a battery of skin-test antigens, but lymphocytes from all patients studied responded normally to in vitro phytohemagglutinin stimulation. A "blocking" factor found in the serum of 3 patients suppressed the in bitro transformation of normal Candida-responsive lymphocytes by Candida albicans antigen. "Cold" lymphocytotoxins were detected in the sera of 10 patients, but in only 3 of 19 control sera. Although the significance of these findings is unknown, they may possibly have pathogenetic relevance in a small number of the patients studied.