[Light chain multiple myeloma revealed by an amyloid arthropathy. A report of two cases].

INTRODUCTION

Amyloid arthropathy occurs in 5-15% of patients with multiple myeloma. It is rarely inaugural. Some cases are reported in which the articular manifestations are present many months before the diagnosis of myeloma. We report two unusual cases where the amyloid arthropathy reveals the multiple myeloma.

EXEGESIS: Case 1: A 54-year-old man take medical advice for a polyarthritis evolving for 6 months. He has no evidence of multiple myeloma except a hypercalcemia and a hypoalbuminemia. The diagnosis of multiple myeloma is based on an immunobinding of plasmatic proteins. It is a light chain multiple myeloma, lambda type. Amylosis is revealed by biopsy specimens from the synovial tissue of the knee. The patient died rapidly because of an intestinal hemorrhage. Case 2: A 78-year-old woman complains from a polyarthritis evolving for 4 months. She has besides an elevated erythrocyte sedimentation rate, an anemia and a renal insufficiency, a profound hypogammaglobulinemia. There is no radiological abnormalities. The diagnosis of multiple myeloma is based on serum and urine immunoelectrophoresis. It is a light chain multiple myeloma, lambda type. The patient is at her sixth monthly course of cyclophosphamid and prednisone. As far as amyloid arthropathy is concerned, it is relatively improved by corticoid intra-articular injections.

CONCLUSION

These are two case reports of a light chain multiple myeloma of lambda type, associated to an amyloid arthropathy in its polyarticular presentation, mimicking a rheumatoïd arthritis. The revelatory nature of the amyloid arthropathy is interesting to report.