title: Severe intraglomerular detachment of podocytes in a Gitelman syndrome patient.
abstract: We report the case of a 38-year-old woman diagnosed with Gitelman syndrome. A kidney biopsy showed abundant floating cells in the Bowman's space of the mildly cystic glomeruli, moderate tubulointerstitial changes and apparent intimal thickening of small arteries. These floating cells were immunohistologically identified as podocytes, by the expression of podocalyxin, vimentin, Wilms' tumor 1, synaptopodin and nephrin with positivities of 100%, 88.4%, 80.4%, 74.7% and 22.6%, respectively. In these phenotypes, nephrin expression was notably decreased in both detached and capillary-attached podocytes in comparison with normal control podocytes. Immunostaining of both detached and capillary-attached podocytes for Bax, Bcl-2, desmin, fibroblast-specific protein-1, α-smooth muscle actin and Ki-67 was negative, as were TUNEL assays. These results suggest that apoptosis and epithelial-mesenchymal transition were not the main cause of podocyte detachment in this patient. In addition, levels of urinary podocalyxin were not elevated, suggesting the detached podocytes were not excreted in the urine. To the best of our knowledge, this is the first report of severe intraglomerular non-apoptotic detachment of podocytes in Gitelman syndrome. This podocyte detachment may be associated with nephron obstruction and reduced nephrin expression.
authors.affiliation: Division of Nephrology, Department of General Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan. ntakahas@u-fukui.ac.jp
authors.forename: Naoki
authors.initials: N
authors.lastname: Takahashi
authors.forename: Hideki
authors.initials: H
authors.lastname: Kimura
authors.forename: Shinichi
authors.initials: S
authors.lastname: Mizuno
authors.forename: Masanori
authors.initials: M
authors.lastname: Hara
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Hirayama
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kurosawa
authors.forename: Shouji
authors.initials: S
authors.lastname: Tsutaya
authors.forename: Minoru
authors.initials: M
authors.lastname: Yasujima
authors.forename: Seiji
authors.initials: S
authors.lastname: Yokoi
authors.forename: Daisuke
authors.initials: D
authors.lastname: Mikami
authors.forename: Kenji
authors.initials: K
authors.lastname: Kasuno
authors.forename: Hironobu
authors.initials: H
authors.lastname: Naiki
authors.forename: Masayuki
authors.initials: M
authors.lastname: Iwano
authors.forename: Haruyoshi
authors.initials: H
authors.lastname: Yoshida
mesh_terms: D000328:Adult; D005260:Female; D053579:Gitelman Syndrome / Q000473:pathology*; D006801:Humans; D007678:Kidney Glomerulus / Q000473:pathology; D008565:Membrane Proteins / Q000096:biosynthesis; D050199:Podocytes / Q000378:metabolism / Q000473:pathology*; D012795:Sialoglycoproteins / Q000096:biosynthesis
chemical_list: D008565:Membrane Proteins; D012795:Sialoglycoproteins; C113267:nephrin; C001643:podocalyxin