C-KIT MUTATION AND OSTEOPETROSIS-LIKE OSTEOPATHY IN A PATIENT WITH SYSTEMIC MAST-CELL DISEASE

We describe the case of a 69-year-old man with systemic mastocytosis a nd severe osteopetrosis who carries a somatic activating mutation in t he c-kit proto-oncogene. The patient initially presented with urticari a pigmentosa, progressing to systemic mast cell disease with severe an emia due to bone marrow involvement, chronic diarrhea, and hepatosplen omegaly, Direct sequencing using amplimers from reverse transcriptase- polymerase chain reactions (RT-PCR) from skin mast cell-derived RNA re vealed a point mutation in the c-kit proto-oncogene at position 2468, introducing a new recognition site for the restriction endonuclease Hi nfI, Treatment with interferon-alpha 2a, prednisone, and erythropoieti n was initiated. Subsequently, clinical sysmptoms improved significant ly and hemoglobin levels are now stable at 13 g/dl.