Light chain deposition disease with typical morphologic and ultrastructural findings

Abstract

Light chain deposition disease (LCDD), a rare form of monoclonal gammopathy, is characterized by deposits of amorphous light-chain material mainly in the kidneys and usually associated with Multiple Myeloma (MM). A patient with LCDD having typical morphological, immunohistochemical and ultrastructural changes in kidney biopsy was diagnosed and presented here. We described a 55 year-old woman who had presented with generalized edema, malaise, nausea and vomiting. Laboratory examination revealed anemia, hypergammaglobulinemia, hypoalbuminemia, Bence-Jones proteinuria. Diagnosis of MM was established on the basis of laboratory features, bone marrow aspiration (material was insufficient but had 15-20% plasma cells) and trephine bone marrow biopsy (plasma cell infiltration with moderate reticulin). Renal biopsy disclosed prominent nodular expansion of the mesangium. Ultrastructurally granular electron dense deposits were observed along the glomerular and tubular basement membrane and mesangium typical of LCDD. An immunohistochemical study showed depositions of kappa light chain in the nodules and tubular basement membrane. Patient was accepted as LCDD and treated with 6 course of VAD (including vincristine, doxorubicine, dexamethasone). Partial remission was achieved and high dose chemotherapy and stem cell transplantation were planned.