ABSTRACT
A Thai male, aged 36 yrs, presented with chronic progressive sensorimotor polyneuropathy and mixed osteosclerotic and lytic lesions at the lumbar vertebrae (L). Generalized hyperpigmentation, bilateral gynecomastia, small testes, hepatomegaly, lymphadenopathy and ascites were observed. Computerized tomography of the lumbosacral spines revealed osteosclerotic changes at L3,4,5 with spiculated bony proliferation at the transverse processes and posterior components of the spines. Histopathological examination of the lesion was compatible with plasmacytoma. Proliferative vasculopathy was demonstrated in plasmacytoma. Serum immunofixation showed an IgM monoclonal gammopathy. Further investigation demonstrated secondary adrenal insufficiency with low level of plasma testosterone. The patient responded well to local radiotherapy and intermittent chemotherapy with melphalan and prednisolone. The histopathological findings of proliferative vasculopathy suggested the important role of capillary leakage as a factor responsible for systemic manifestations in the POEMS syndrome. The reported cases of this syndrome among Thais are summarized.