title: Adenine phosphoribosyltransferase deficiency: a case diagnosed by GC-MS identification of 2,8-dihydroxyadenine in urinary crystals.
abstract: Light microscopy of the urinary sediment from a child suffering from urinary tract disease showed massive crystalluria. Most of the sediment consisted of characteristic round and brownish crystals. 2,8-Dihydroxyadenine was identified in the crystals by means of gas chromatography-mass spectrometry. The diagnosis of adenine phosphoribosyltransferase deficiency was established by the finding of a very low activity of this enzyme in erythrocytes from the patient, and of half the normal activity in the patients. The patient was first treated with a diet low in purine and with a high liquid intake. She stayed symptomless on this regimen, but the crystalluria persisted. On low doses of allopurinol the crystalluria disappeared.
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000652:urine; D000228:Adenine Phosphoribosyltransferase / Q000097:blood / Q000172:deficiency*; D002675:Child, Preschool; D004912:Erythrocytes / Q000201:enzymology; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D010430:Pentosyltransferases / Q000172:deficiency*; D011686:Purine-Pyrimidine Metabolism, Inborn Errors / Q000201:enzymology / Q000652:urine*
chemical_list: C002993:2,8-dihydroxyadenine; D010430:Pentosyltransferases; D000228:Adenine Phosphoribosyltransferase; D000225:Adenine