title: Discrete renal deposition of IgM heavy chain and κ light chain in Waldenström macroglobulinemia (IgM-κ).
abstract: We report previously undescribed renal lesions associated with monoclonal gammopathy in a 59-year-old man with Waldenström macroglobulinemia (IgM-κ). Light microscopy showed mesangial proliferation and thickening of glomerular basement membranes (GBMs) and tubular basement membranes (TBMs). Neither intraglomerular thrombi nor nodular glomerulosclerosis was observed. Immunofluorescence studies disclosed essentially discrete localization of IgM heavy chain within the mesangial area and κ light chain along GBMs and TBMs. Electron microscopy showed continuous linear deposits of finely granular electron-dense material along the inner aspect of GBMs and TBMs. Repeated rituximab treatment and chemotherapy (melphalan and prednisolone) led to the improvement of proteinuria.
authors.affiliation: Department of Hematology, Nephrology, and Rheumatology , Akita University Graduate School of Medicine , Akita , Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Komatsuda
authors.affiliation: Department of Hematology, Nephrology, and Rheumatology , Akita University Graduate School of Medicine , Akita , Japan.
authors.forename: Rie
authors.initials: R
authors.lastname: Masai
authors.affiliation: Department of Hematology, Nephrology, and Rheumatology , Akita University Graduate School of Medicine , Akita , Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Togashi
authors.affiliation: Department of Nephrology and Dialysis , Akita Kumiai General Hospital , Akita , Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ohtani
authors.affiliation: Department of Hematology, Nephrology, and Rheumatology , Akita University Graduate School of Medicine , Akita , Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Sawada
authors.affiliation: Department of Hematology, Nephrology, and Rheumatology , Akita University Graduate School of Medicine , Akita , Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Wakui
keywords: Waldenström macroglobulinemia; kidney lesion; monoclonal immunoglobulin deposition disease; rituximab