title: Renal oxypurine deposition in Lesch-Nyhan syndrome: sonographic evaluation.
abstract: Lesch-Nyhan syndrome is a rare X-linked recessive disorder of purine metabolism associated with a virtually complete deficiency of the enzyme hypoxanthine-guanine phosphoribosyl-transferase (HPRT). The disease is characterized by hyperuricemia, self-multilation, choreoathetosis, spasticity, and mental retardation. The abnormalities of purine metabolism are present at birth and may lead to uric acid crystalluria and stone formation early in life. Radiographic findings described in Lesch-Nyhan syndrome include faintly radio-opaque stones on abdominal radiographs or, if renal disease is present, small kidneys with poor function on intravenous urogram. Radiolucent stones are usually composed of uric acid; however, several cases of xanthine and hypoxanthine-containing calculi in Lesch-Nyhan patients receiving allopurinl therapy have also been described. Oxypurine is the collective name for the compounds hypoxanthine, xanthine, and uric acid, and all may be radiolucent. We report a case of Lesch-Nyhan syndrome with presumed renal parenchymal oxypurine deposition demonstrated readily by ultrasonography but not detected on standard radiographs or intravenous urograms.
authors.affiliation: Department of Diagnostic Radiology and Nuclear Medicine, Children's Hospital, Stanford, California.
authors.forename: S K
authors.initials: SK
authors.lastname: Stevens
authors.forename: B R
authors.initials: BR
authors.lastname: Parker
mesh_terms: D000493:Allopurinol / Q000009:adverse effects*; D002648:Child; D006801:Humans; D019271:Hypoxanthine; D007042:Hypoxanthines / Q000032:analysis; D007669:Kidney Calculi / Q000032:analysis / Q000175:diagnosis* / Q000209:etiology; D007926:Lesch-Nyhan Syndrome / Q000188:drug therapy*; D008297:Male; D014463:Ultrasonography; D014527:Uric Acid / Q000032:analysis; D019820:Xanthine; D014970:Xanthines / Q000032:analysis
chemical_list: D007042:Hypoxanthines; D014970:Xanthines; D019820:Xanthine; D014527:Uric Acid; D019271:Hypoxanthine; D000493:Allopurinol