Pulmonary sarcoidosis associated with acquired humoral and cellular immunodeficiency.

A previously healthy 27-year-old man with class II pulmonary sarcoidosis developed severe humoral immunodeficiency within the course of the disease with an IgG of less than 250 mg/ml and undetectable levels of IgA and IgM. Repeated skin tests were negative for seven common recall antigens. Cellular blood test demonstrated normal numbers of B cells and slight T-cell lymphopenia with a normal T-helper/suppressor subset distribution (ratio 1.6). In contrast, parallel examination of the bronchial alveolar lavage fluid (BAL) demonstrated highly elevated numbers of T cells with a subset ratio of 3.1 and significant numbers of activated T cells as revealed by the expression of Ia and Tac antigens. Functional in vitro assays showed a greatly decreased mitogenic response of blood T cells and diminished production of immunoglobulins. These data indicate that, despite a severely depressed systemic humoral and cellular immune system, T-cell activation can take place at the inflammatory site, potentially causing the lesions characteristic of sarcoidosis.