SUCCESSFUL TREATMENT OF OSTEOPOROSIS IN SYSTEMIC - MASTOCYTOSIS WITH INTERFERON-ALPHA-2B

Osteoporosis is frequently seen in systemic mastocytosis. Although dip hosphonate therapy has been shown to be transiently effective, therapy options for this form of osteopenia are very limited. We have treated three patients with systemic mastocytosis and osteopenia successfully with interferon alpha-2b, Two patients had urticaria pigmentosa and t wo severe back pain due to vertebral compression fractures. All patien ts received a daily interferon dose of 3 x 5 mio units/week s.c. for a period of 6 months, Therapy was well tolerated, and back pain resolve d in both patients, A marked decrease of mast cell numbers in the bone marrow and a significant increase of bone mineralization and bone den sity was observed in all patients. Our data suggest that alpha interfe ron may be a new treatment option for osteopenia in systemic mastocyto sis, radiologic evidence of osteopenia is present in 75% of cases [10] . Bone histology almost always shows a combination of osteosclerosis a nd osteopenia with a stippled radiographic pattern [3]. Symptomatic bo ne disease may manifest with severe bone or back pain due to vertebral compression fractures. Currently, an effective treatment of mastocyto sis associated osteopenia is unknown, although a transient improvement has been reported with diphosphonate therapy [2]. Because a marked ef fect of interferon alpha-2b (IFN) was seen in a patient with malignant mastocytosis [5], we have treated three patients with SM and severe o steoporosis with IFN.