title: Obstructive uropathy and severe acute kidney injury from renal calculi due to adenine phosphoribosyltransferase deficiency.
abstract: BACKGROUND
  Adenine phosphoribosyltransferase (APRT) deficiency is an uncommon genetic cause of chronic kidney disease due to crystalline nephropathy.
  
  
  METHODS
  A case of a Chinese boy with APRT deficiency presenting with severe acute kidney injury secondary to obstructive uropathy from multiple renal calculi was reviewed.
  
  
  RESULTS
  The patient underwent staged removal of the calculi. Infrared spectrometry of the renal calculi showed 2,8-dihydroxyadenine. APRT deficiency was confirmed with abolished APRT enzyme activity in red blood cells. He was started on allopurinol and low purine diet with complete resolution of the residual calculi.
  
  
  CONCLUSIONS
  APRT deficiency should be considered in patients with multiple radiolucent renal calculi.
authors.affiliation: Department of Pediatrics (Nephrology Service), KK Women's and Children's Hospital, Singapore, Singapore.
authors.forename: Siew Le
authors.initials: SL
authors.lastname: Chong
authors.affiliation: Department of Pediatrics (Nephrology Service), KK Women's and Children's Hospital, Singapore, Singapore. Ng.Yong.Hong@kkh.com.sg.|, 100 Bukit Timah Road, Singapore, 229899, Singapore. Ng.Yong.Hong@kkh.com.sg.
authors.forename: Yong Hong
authors.initials: YH
authors.lastname: Ng
mesh_terms: D058186:Acute Kidney Injury / Q000209:etiology*; D000228:Adenine Phosphoribosyltransferase / Q000172:deficiency*; D002681:China; D006801:Humans; D007223:Infant; D007669:Kidney Calculi / Q000150:complications* / Q000209:etiology*; D008297:Male; D008661:Metabolism, Inborn Errors / Q000150:complications*; D012720:Severity of Illness Index; D014517:Ureteral Obstruction / Q000209:etiology*; D001748:Urinary Bladder Neck Obstruction / Q000209:etiology*; D052878:Urolithiasis / Q000150:complications*
chemical_list: D000228:Adenine Phosphoribosyltransferase
keywords: 2,8-dihydroxyadenine; acute renal failure; adenine phosphoribosyltransferase deficiency; urolithiasis