title: An Adult Case of Bartter Syndrome Type III Presenting with Proteinuria.
abstract: Bartter syndrome (BS) I-IV is a rare autosomal recessive disorder affecting salt reabsorption in the thick ascending limb of the loop of Henle. This report highlights clinicopathological findings and genetic studies of classic BS in a 22-year-old female patient who presented with persistent mild proteinuria for 2 years. A renal biopsy demonstrated a mild to moderate increase in the mesangial cells and matrix of most glomeruli, along with marked juxtaglomerular cell hyperplasia. These findings suggested BS associated with mild IgA nephropathy. Focal tubular atrophy, interstitial fibrosis, and lymphocytic infiltration were also observed. A genetic study of the patient and her parents revealed a mutation of the CLCNKB genes. The patient was diagnosed with BS, type III. This case represents an atypical presentation of classic BS in an adult patient. Pathologic findings of renal biopsy combined with genetic analysis and clinicolaboratory findings are important in making an accurate diagnosis.
authors.affiliation: Department of Pathology, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Korea.
authors.forename: Eun Jung
authors.initials: EJ
authors.lastname: Cha
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Korea.
authors.forename: Won Min
authors.initials: WM
authors.lastname: Hwang
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Korea.
authors.forename: Sung-Ro
authors.initials: SR
authors.lastname: Yun
authors.affiliation: Department of Pathology, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Korea.
authors.forename: Moon Hyang
authors.initials: MH
authors.lastname: Park
keywords: Bartter syndrome; Hypokalemia; Juxtaglomerular cell hyperplasia