title: Scanning electron microscopy of 2,8-dihydroxyadenine crystals and stones.
abstract: The lack of purine salvage enzyme, adenine phosphoribosyltransferase (APRT), leads to 2,8-dihydroxyadenine stone formation and/or crystalluria because it is insoluble in urine. Urolithiasis composed of 2,8-dihydroxyadenine is not only formed in a complete defect of APRT, but also in a partial deficiency of this enzyme. The defect is inherited as an autosomal recessive trait, the homozygous state is associated with high urinary levels of 2,8-dihydroxyadenine and with crystalluria, calculus formation, and potential nephrotoxicity. Determination of the APRT activity will facilitate quantification of the enzyme deficiency and elucidation of the hereditary history. 2,8-dihydroxyadenine excretion in the 24-hour urine and its circadian rhythm were determined using a new method of high performance liquid chromatography determination. By means of a standard case presentation, we illustrate the analysis of urinary sediments and calculi as well as the scanning electron microscopic images of this kind of stone.
authors.affiliation: Urologische Universitätsklinik Bonn, Federal Republic of Germany.
authors.forename: P
authors.initials: P
authors.lastname: Winter
authors.forename: A
authors.initials: A
authors.lastname: Hesse
authors.forename: K
authors.initials: K
authors.lastname: Klocke
authors.forename: R M
authors.initials: RM
authors.lastname: Schaefer
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000032:analysis / Q000652:urine; D000228:Adenine Phosphoribosyltransferase / Q000097:blood / Q000172:deficiency*; D000328:Adult; D000493:Allopurinol / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007669:Kidney Calculi / Q000737:chemistry* / Q000201:enzymology / Q000648:ultrastructure*; D008297:Male; D008855:Microscopy, Electron, Scanning; D013055:Spectrophotometry, Infrared
chemical_list: C002993:2,8-dihydroxyadenine; D000493:Allopurinol; D000228:Adenine Phosphoribosyltransferase; D000225:Adenine