IgD-Lambda Multiple Myeloma without Renal Failure: An Unusual Presentation

Abstract

Immunoglobulin D (IgD) multiple myeloma is a rare form of myeloma having often an aggressive course, affecting 2% of all cases. It shows frequentely renal failure, Bence Jones proteinuria and the difficulties of diagnosis. We report a case of a 59 years old man with IgD multiple myeloma associated with good renal function. The patient was hospitalized in the hematology department for bone pain and alteration of the general condition. A further evaluation for multiple myeloma revealed presence of a monoclonal protein band in Beta2 region in serum protein electrophoresis (SPE). Urine protein electrophoresis (UPE) showed presence of BenceJones proteinuria.The immunofixation electrophoresis (IE) of the serum reported as IgD-Lambda paraproteinaemia. Laboratory studies showed also an anemia , hypercalcemia, but fortunatuly, our patient did not have renal failure, as is common with myeloma. Bone marrow examination showed infiltration by plasma cells. Thus, the patient was put on chemotherapy and stem cell autotransplantation with a good clinical and biological improvement. This case is reported to emphasize the importance of performing IgD immunofixation routinely for all suspected multiple myeloma patients because many cases are erroneously diagnosed as light chain disease. And it describes a rare case of an even rarer and uncommon situation and highlights the fortunate situation of this patient's unfortunate disease.