title: Progression of Monoclonal Gammopathy with Undetermined Significance to Multiple Myeloma Diagnosed by Kidney Biopsy: A Case Report.
abstract: Monoclonal gammopathy with undetermined significance (MGUS) carries a risk of progression to multiple myeloma, and progression is usually diagnosed with changes in M-protein or bone marrow biopsy. We report a case of 62-year-old female patient showing MGUS progression to multiple myeloma without significant changes in M-protein but diagnosed by kidney biopsy. During the follow-ups, azotemia and tubular proteinuria were aggravated without elevation of M-protein. Kidney biopsy showed intratubular and glomerular inclusions associated with plasma cell dysplasia. The progression of MGUS to multiple myeloma was diagnosed by this kidney biopsy. The patient's renal function and tubular proteinuria were markedly improved after chemotherapy.
authors.affiliation: Department of Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jin Hae
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Kim
authors.affiliation: Department of Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Young Nam
authors.initials: YN
authors.lastname: Kim
authors.affiliation: Department of Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Hye In
authors.initials: HI
authors.lastname: Kim
authors.affiliation: Department of Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jun Young
authors.initials: JY
authors.lastname: Kim
authors.affiliation: Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Ghee Young
authors.initials: GY
authors.lastname: Kwon
authors.affiliation: Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Kihyun
authors.initials: K
authors.lastname: Kim
authors.affiliation: Division of Nephrology, Department of Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Hye Ryoun
authors.initials: HR
authors.lastname: Jang
keywords: Monoclonal gammopathy of undetermined significance; Multiple myeloma; Proteinuria