Lymphocytopenia-associated sarcoidosis: CD4+ T-cell hypo-responsiveness to IL-2 and lectin

Despite classical identification of immune response impairment in sarcoidosis, such as anergy to delayed skin tests, the characterization of contributing mechanisms are still uncertain and infectious events complicating the course of the disease are unfrequent. Rarely, additional quantitative T-cell defects are reported in association with the disease. Although mechanisms of lymphocyte disorders are unknown, lymphocytopenia is usually revealed by an opportunistic infection.