title: Cutaneous calcification in patients with end-stage renal disease: a regulated process associated with in situ osteopontin expression.
abstract: BACKGROUND
  Cutaneous calcification, or calcinosis cutis (CC), is found in approximately 1% of patients with end-stage renal disease (ESRD) undergoing chronic dialysis. While the pathogenesis is not well understood, it may be similar to those for medial and intimal vascular calcifications, which are actively regulated processes.
  
  
  METHODS
  In a retrospective study of 9 patients, the role of an active calcification process leading to CC was assessed by the immunohistochemical detection of osteopontin, which is a regulator of osseous and extra-osseous calcification processes. Calcinosis cutis was associated with female sex, vascular comorbidity, inconstant secondary hyperparathyroidism, and elevated levels of plasma calcium-phosphorus product. Six patients had a favorable outcome after the lowering of plasma calcium levels during dialysis or after parathyroidectomy.
  
  
  CONCLUSIONS
  Calcinosis of the vascular media of subcutaneous vessels was the most common histologic feature and was always associated with osteopontin staining, suggesting that CC is a regulated process. Moreover, to our knowledge, extravascular staining of osteopontin in sweat glands, nerves, and macrophages was demonstrated for the first time in this study.
authors.affiliation: Department of Pathology, AP-HP, Saint-Louis Hospital, INSERM U728, Paris, France. jacqueline.rivet@sls.ap-hop-paris.fr
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Rivet
authors.forename: Celeste
authors.initials: C
authors.lastname: Lebbé
authors.forename: Pablo
authors.initials: P
authors.lastname: Urena
authors.forename: Florence
authors.initials: F
authors.lastname: Cordoliani
authors.forename: Franck
authors.initials: F
authors.lastname: Martinez
authors.forename: Anne C
authors.initials: AC
authors.lastname: Baglin
authors.forename: Pierre
authors.initials: P
authors.lastname: Aubert
authors.forename: Selim
authors.initials: S
authors.lastname: Aractingi
authors.forename: Pierre
authors.initials: P
authors.lastname: Ronco
authors.forename: Philippe
authors.initials: P
authors.lastname: Fournier
authors.forename: Anne
authors.initials: A
authors.lastname: Janin
mesh_terms: D000328:Adult; D000368:Aged; D002114:Calcinosis / Q000453:epidemiology* / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D005260:Female; D005602:France / Q000453:epidemiology; D006801:Humans; D007150:Immunohistochemistry; D007676:Kidney Failure, Chronic / Q000150:complications*; D008297:Male; D008499:Medical Records; D008875:Middle Aged; D053495:Osteopontin; D012189:Retrospective Studies; D012795:Sialoglycoproteins / Q000378:metabolism; D012871:Skin Diseases / Q000453:epidemiology* / Q000209:etiology / Q000378:metabolism / Q000473:pathology
chemical_list: C506895:SPP1 protein, human; D012795:Sialoglycoproteins; D053495:Osteopontin