title: Progression of kidney disease varies between families with defects in the polycystic kidney disease type 1 gene in eastern Finland.
abstract: OBJECTIVE
  To characterize, for the first time, the phenotype and clinical course of autosomal dominant polycystic kidney disease (ADPKD) in Finnish patients.
  
  
  METHODS
  All patients underwent an abdominal sonographic examination and most of those with ADPKD underwent magnetic resonance angiography of the head. Haplotype analysis was used to classify 20 ADPKD families into those with defects in either the polycystic kidney disease type 1 (PKD1) or polycystic kidney disease type 2 (PKD2) genes. Evaluation of the rate of progression of kidney disease in patients with ADPKD was based on creatinine values.
  
  
  RESULTS
  Haplotype analysis showed that 16 families had defects in the PKD1 gene and one had defects in the PKD2 gene. Three families were excluded because of uninformative haplotypes. The final study population consisted of 79 unaffected family members, 109 patients with defects in the PKD1 gene and 10 with defects in the PKD2 gene. Higher prevalences of hepatic cysts (3% in healthy relatives, 60% in PKD1 patients and 90% in PKD2 patients; p < 0.001), subarachnoid hemorrhage or cerebral aneurysms (1%, 12% and 0%, respectively; p < 0.001), proteinuria (1%, 23% and 0%, respectively; p < 0.001) and hematuria (5%, 30% and 0%, respectively; p < 0.001) were found in PKD1 patients compared to the healthy relatives. PKD1 patients had a faster progression of kidney disease than PKD2 patients (p < 0.001). The progression of kidney disease varied substantially among the PKD1 families.
  
  
  CONCLUSIONS
  The relative proportions of PKD1 and PKD2 patients and the phenotype of ADPKD were similar in our Finnish patients compared to previous studies in other populations. However, the progression of kidney disease differed substantially among PKD1 families, indicating a heterogeneic genetic background of PKD1 in Finnish patients.
authors.affiliation: Department of Medicine, Kuopio University Hospital, Finland. anne.lumiaho@kuh.fi
authors.forename: Anne
authors.initials: A
authors.lastname: Lumiaho
authors.forename: Risto
authors.initials: R
authors.lastname: Ikäheimo
authors.forename: Jussi
authors.initials: J
authors.lastname: Pihlajamäki
authors.forename: Raija
authors.initials: R
authors.lastname: Miettinen
authors.forename: Lea
authors.initials: L
authors.lastname: Niemitukia
authors.forename: Ritva
authors.initials: R
authors.lastname: Vanninen
authors.forename: Erkki
authors.initials: E
authors.lastname: Lampainen
authors.forename: Markku
authors.initials: M
authors.lastname: Laakso
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018450:Disease Progression; D005260:Female; D005387:Finland; D006239:Haplotypes; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D008875:Middle Aged; D009154:Mutation; D010641:Phenotype; D016891:Polycystic Kidney, Autosomal Dominant / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology*; D011506:Proteins / Q000235:genetics*; D050396:TRPP Cation Channels
chemical_list: D008565:Membrane Proteins; D011506:Proteins; D050396:TRPP Cation Channels