A case of POEMS syndrome associated with essential thrombocythaemia and dermal mastocytosis.

We describe a case of POEMS syndrome presenting with the recognized features of polyneuropathy, organomegaly, endocrine abnormalities, monoclonal protein, skin changes and anasarca. The patient was found to have both a solitary sclerotic plasmacytoma of the pelvis and evidence of Castleman's disease of lymph nodes. A number of unusual and unique features are also documented. Histological examination of affected skin demonstrated changes similar to urticaria pigmentosa including local oedema and mast cell infiltration. There was marked thrombocythaemia which has been seen in only one previous case and in addition the patient developed diffuse vascular calcification in the absence of recognized aetiological factors. Radiotherapy of the pelvic lesion and chemotherapy to control the myeloproliferative disorder gave rise to significant improvement in neuropathy. Control of anasarca required steroid therapy in addition to diuretics. The significance of these observations is discussed in relation to previous reports.