title: Kidney Function After the First Kidney Stone Event.
abstract: OBJECTIVE
  To determine whether there is a persistent decline in kidney function after the first kidney stone event.
  
  
  METHODS
  Incident symptomatic stone formers and age- and sex-matched controls underwent 2 study visits 90 days apart to assess kidney function, complete a survey, and have their medical records reviewed. Kidney function was compared between stone formers and controls adjusting for clinical, blood, and urine risk factors.
  
  
  RESULTS
  There were 384 stone formers and 457 controls. At visit 1, a median of 104 days after the stone event, stone formers compared with controls had similar serum creatinine (0.86 vs 0.84 mg/dL; P=.23), higher serum cystatin C (0.83 vs 0.72 mg/L; P<.001), higher urine protein (34.2 vs 19.7 mg/24 h; P<.001) levels, and were more likely to have albuminuria (24 h urine albumin >30 mg: 5.4% vs 2.2%; P=.02). Findings were similar after adjustment for risk factors and at visit 2, a median of 92 days after visit 1. In the 173 stone formers with serum creatinine levels from care before study participation, the mean serum creatinine level was 0.84 mg/dL before the stone event, increased to 0.97 mg/dL (P<.001) at the stone event, but returned to 0.85 mg/dL (P=.38) after the stone event (visit 1).
  
  
  CONCLUSIONS
  Incident symptomatic stone formers have a rise in serum creatinine levels that resolves. However, stone formers have sustained higher cystatin C levels and proteinuria that may affect long-term risk of chronic kidney disease.
authors: Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN.
authors: William E
authors: WE
authors: Haley
authors: Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN.
authors: Felicity T
authors: FT
authors: Enders
authors: Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN.
authors: Lisa E
authors: LE
authors: Vaughan
authors: Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN.
authors: Ramila A
authors: RA
authors: Mehta
authors: Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN.
authors: Maxton E
authors: ME
authors: Thoman
authors: Department of Radiology, Mayo Clinic, Rochester, MN.
authors: Terri J
authors: TJ
authors: Vrtiska
authors: Department of Urology, Mayo Clinic, Rochester, MN.
authors: Amy E
authors: AE
authors: Krambeck
authors: Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN.
authors: John C
authors: JC
authors: Lieske
authors: Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN. Electronic address: Rule.andrew@mayo.edu.
authors: Andrew D
authors: AD
authors: Rule
mesh_terms: D000328:Adult; D000419:Albuminuria / Q000378:metabolism; D016022:Case-Control Studies; D003404:Creatinine / Q000097:blood; D055316:Cystatin C / Q000097:blood; D005260:Female; D006801:Humans; D007668:Kidney / Q000503:physiopathology*; D007669:Kidney Calculi / Q000378:metabolism* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D012016:Reference Values
chemical_list: D055316:Cystatin C; D003404:Creatinine