Cytokines in the culture supernatant of concanavalin A-stimulated macrophages/lymphocytes isolated from bronchoalveolar lavage (BAL) fluid in a 29-year-old patient with primary pulmonary cryptococcosis were evaluated to study the immune reaction against Cryptococcus neoformans in the lung. Before fungicidal therapy, levels of interferon-gamma and interleukin-10 were markedly elevated, and declined after therapy. There were no changes in interleukin-2 or interleukin-4 throughout the clinical course. This result suggests that IFN-gamma and IL-10 may be involved in the immune reaction against pulmonary cryptococcosis.