title: International registry for primary hyperoxaluria.
abstract: OBJECTIVE
  Primary hyperoxaluria (PH) is an inherited disorder that causes calcium urolithiasis and renal failure. Due to its rarity, experience at most centers with this disease is limited.
  
  
  METHODS
  A secure, web-based, institutional review board/ethics committee and American Health Insurance Portability and Accountability Act (HIPAA)-compliant registry was developed to facilitate international contributions to a data base. To date 95 PH patients have been entered.
  
  
  RESULTS
  PH type was confirmed in 84/95 (PH1 79%, PH2 9%). Mean age +/- SD at symptom onset was 9.5 +/- 10.2 (median 5.5) years whereas age at diagnosis was 15.0 +/- 15.2 (median 10.0) years. Urolithiasis was present at diagnosis in 90% (mean 7, median 1, stones prior to diagnosis) and nephrocalcinosis in 48%. Surprisingly 15% of the patients were asymptomatic at the time of diagnosis. Nineteen of the 95 patients were first recognized to have PH after they had reached end-stage renal disease, with the diagnosis made only after kidney transplantation in 7 patients. Patients were followed for 12.1 +/- 10.6 (median 9.4) years. Thirty-four of 95 progressed to end-stage renal failure, before (19 patients) or after (15 patients) diagnosis. In the PH1 cohort actuarial renal survival was 64% at 30 years of age, 47% at 40 years, and 29% at 50 years.
  
  
  CONCLUSIONS
  We have developed a PH registry, and demonstrated the feasibility of this secure, web-based approach for data entry. By facilitating accumulation of an increasing cohort of patients, this registry should allow more complete characterization of clinical expression of PH, an appreciation of geographic variability, and identification of treatment outcomes.
authors.affiliation: Department of Internal Medicine, Division of Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, Minn. 55905, USA. Lieske.John@mayo.edu
authors.forename: John C
authors.initials: JC
authors.lastname: Lieske
authors.forename: Carla G
authors.initials: CG
authors.lastname: Monico
authors.forename: W Scott
authors.initials: WS
authors.lastname: Holmes
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Bergstralh
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Slezak
authors.forename: Audrey L
authors.initials: AL
authors.lastname: Rohlinger
authors.forename: Julie B
authors.initials: JB
authors.lastname: Olson
authors.forename: Dawn S
authors.initials: DS
authors.lastname: Milliner
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D018450:Disease Progression; D005240:Feasibility Studies; D006801:Humans; D006960:Hyperoxaluria, Primary / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D007223:Infant; D038622:Internationality; D007668:Kidney / Q000503:physiopathology; D007676:Kidney Failure, Chronic / Q000209:etiology / Q000601:surgery; D016030:Kidney Transplantation; D012042:Registries; D012189:Retrospective Studies