[IgD multiple myeloma mimicking free light chain myeloma complicated by factor X deficiency: a case report].

IgD myeloma is an extremely rare haemopathy with severe clinical presentation. It can be confused with non-secretory or free light chain myeloma. We here report the case of a 72-year old female patient presenting with bone pain and diffuse ecchymosis and deterioration of her general condition. Laboratory tests showed monoclonal gammopathy associated with severe acute renal failure and low total protein (TP) (48%) with factor X deficiency. Etiological assessment confirmed the diagnosis of IgD lambda myeloma stage IIIb, according to Durie and Salmon, International Staging System (ISS) score III unfavorable cytogenetics. Patient's outcome was favorable after treatment with proteasome inhibitor, anti-CD 38 and corticosteroid therapy. Adequate treatment of IgD myeloma, using new therapeutic approaches and hematopoietic stem cell autotransplantation, can improve the prognosis.