Effects of long-term low-dose corticosteroid therapy on humoral immunity

Background: Corticosteroids are agents that suppress the immune system. Their suppressive activity is predominantly restricted to cell-mediated immunity, with a marginal inhibitory effect on humoral immunity. Objective: To describe an acquired reversible B-cell deficiency in a patient treated with low-dose corticosteroids for 36 years. Methods: A broad range of T- and B-cell parameters were studied over time, during and after discontinuation of corticosteroid therapy. Published works on this topic in animal and human models are reviewed. The findings unique to this patient are highlighted. Results: While undergoing long-term corticosteroid therapy, a patient developed a clinical and immunologic picture suggestive of common variable immunodeficiency, with predominantly qualitative and quantitative B-cell abnormalities. These abnormalities resolved within 2 years after tapering of corticosteroid therapy. Conclusions: Long-term low-dose corticosteroid use may reversibly decrease B-cell counts and specific antibody responses.