SEVERE OSTEOPOROSIS DUE TO SYSTEMIC MAST-CELL DISEASE - SUCCESSFUL TREATMENT WITH INTERFERON-ALPHA-2B

We describe a 33-yr-old man suffering from severe vertebral osteoporos is and urticaria pigmentosa due to systemic mast cell disease (SMCD). Because i.v. clodronate therapy could not prevent further vertebral fr actures, an additional treatment with interferon alpha-2b was initiate d. During 24 months of treatment, our patient had no further pain epis odes, no new vertebral fractures were discovered, trabecular bone mine ral density (BMD) increased significantly and urticarial symptoms impr oved. Nevertheless, the extent of skin lesions remained unchanged. Oil histological examination, a remarkable decrease of mast cells was obs erved in the bone marrow, but not in the skin. Five months after disco ntinuation of interferon alpha-2b, trabecular BMD decreased and urtica rial symptoms deteriorated. These findings illustrate a beneficial eff ect of interferon alpha-2b on SMCD-induced osteoporosis as well as urt icarial symptoms, and raise the question whether this treatment may ha ve a diverse impact on mast cell populations in different tissues.