title: Stone forming risk factors in patients with type Ia glycogen storage disease.
abstract: OBJECTIVE
  Patients with type Ia glycogen storage disease have an increased recurrent nephrolithiasis rate. We identified stone forming risk factors in patients with type Ia glycogen storage disease vs those in stone formers without the disease.
  
  
  METHODS
  Patients with type Ia glycogen storage disease were prospectively enrolled from our metabolic clinic. Patient 24-hour urine parameters were compared to those in age and gender matched stone forming controls.
  
  
  RESULTS
  We collected 24-hour urine samples from 13 patients with type Ia glycogen storage disease. Average +/- SD age was 27.0 +/- 13.0 years and 6 patients (46%) were male. Compared to age and gender matched hypocitraturic, stone forming controls patients had profound hypocitraturia (urinary citrate 70 vs 344 mg daily, p = 0.009). When comparing creatinine adjusted urinary values, patients had profound hypocitraturia (0.119 vs 0.291 mg/mg creatinine, p = 0.005) and higher oxalate (0.026 vs 0.021 mg/mg creatinine, p = 0.038) vs other stone formers.
  
  
  CONCLUSIONS
  Patients with type Ia glycogen storage disease have profound hypocitraturia, as evidenced by 24-hour urine collections, even compared to other stone formers. This may be related to a recurrent nephrolithiasis rate greater than in the overall population. These findings may be used to support different treatment modalities, timing and/or doses to prevent urinary lithiasis in patients with type Ia glycogen storage disease.
authors.affiliation: Division of Medical Genetics, Duke University Medical Center, Durham, North Carolina 27710, USA.
authors.forename: Charles D
authors.initials: CD
authors.lastname: Scales
authors.forename: Aravind S
authors.initials: AS
authors.lastname: Chandrashekar
authors.forename: Marnie R
authors.initials: MR
authors.lastname: Robinson
authors.forename: David A
authors.initials: DA
authors.lastname: Cantor
authors.forename: Jennifer
authors.initials: J
authors.lastname: Sullivan
authors.forename: George E
authors.initials: GE
authors.lastname: Haleblian
authors.forename: Victor A
authors.initials: VA
authors.lastname: Leitao
authors.forename: Roger L
authors.initials: RL
authors.lastname: Sur
authors.forename: Kristy M
authors.initials: KM
authors.lastname: Borawski
authors.forename: Dwight
authors.initials: D
authors.lastname: Koeberl
authors.forename: Priya S
authors.initials: PS
authors.lastname: Kishnani
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Preminger
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D005953:Glycogen Storage Disease Type I / Q000150:complications* / Q000652:urine*; D006801:Humans; D008297:Male; D008875:Middle Aged; D053040:Nephrolithiasis / Q000453:epidemiology / Q000209:etiology* / Q000652:urine*; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors; D055815:Young Adult