MULTIPLE MYELOMA ASSOCIATED WITH AL AMYLOIDOSIS PRESENTING AS NEPHROTIC SYNDROME: A RARE CASE REPORT

Abstract

Background: AL amyloidosis is an uncommon systemic condition due to deposits of monoclonal immunoglobulin light chains in different organs, predominantly kidneys. Myeloma is a plasma cell tumor which can occur together with AL amyloidosis and can result in organ dysfunction and poor prognosis. Renal involvement is often manifested as nephrotic syndrome and can be the first presentation of the disease. Case Presentation : A 62-year-old man had come with progressive bilateral pedal edema, facial swelling, foamy urine, generalised weakness, and anorexia for 3 months. His investigations were suggestive of nephrotic range proteinuria (8.4 g/day), hypoalbuminemia, hyperlipidemia, anemia, raised erythrocyte sedimentation rate, and impaired renal function. His serum protein electrophoresis showed a monoclonal M-spike while immunofixation electrophoresis was suggestive of monoclonal lambda light chains. The bone marrow biopsy showed approximately 30% clonal plasma cells suggesting multiple myeloma. The renal biopsy was positive for Congo red staining with apple green birefringence in polarised light suggesting amyloidosis. He was started on a chemotherapy combination consisting of bortezomib, cyclophosphamide, and dexamethasone along with treatment for nephrotic syndrome. There was marked improvement in his proteinuria, serum albumin, renal function, and other hematological parameters. Conclusion: This case underscores the necessity to include AL amyloidosis and plasma cell dyscrasia in the differential diagnosis in cases where there is an atypical presentation of nephrotic syndrome. It is crucial to make an early diagnosis through appropriate investigations such as laboratory studies, bone marrow study, and kidney biopsy for better prognosis.