A case of 2,8-dihydroxyadenine crystal urine that did not show urine calculus

• NAGATA Katsuhiro

  Medical Laboratory Center, Kanazawa Medical University Hospital

• TANAKA Yoshi

  Medical Laboratory Center, Kanazawa Medical University Hospital

• MATSUMOTO Masami

  Medical Laboratory Center, Kanazawa Medical University Hospital

• TANAKA Chizu

  Medical Laboratory Center, Kanazawa Medical University Hospital

• NITTA Kyoko

  Department of Diabetes Internal Secretion Internal Medicine, Kanazawa Medical University

• MIYAZAWA Katsuhito

  Department of Urology, Kanazawa Medical University

• IINUMA Yoshitsugu

  Medical Laboratory Center, Kanazawa Medical University Hospital Department of Infectious Diseases, Kanazawa Medical University

Bibliographic Information

Other Title

• 尿路結石を認めなかった2,8-DHA結晶尿の1症例

Abstract

Adenine phosphoribosyltransferase (APRT) deficiency results in 2,8-dihydroxyadenine (DHA) urolithiasis with the deposition of 2,8-DHA crystals of various sizes in the bladder. Here, we report the case of a male patient in his 60s, who was diagnosed as having diabetes in 2012, and regularly came to our hospital for the treatment of chronic renal failure caused by diabetic nephropathy. Crystals suspected to be composed of 2,8-DHA were first detected about 2 years later and were consistently detected thereafter. Inspection of their chemical properties suggested that these crystals were composed of 2,8-DHA. However, the final determination was difficult as they could not be identified by infrared spectroscopic analysis, and computed tomography did not show any urinary calculus. Genetic analysis showed the patient to be homozygous for the Japanese mutant gene APRT*J/APRT*J. The timing of the first detection of 2,8-DHA coincided with that of eGFR deterioration. Therefore, the possibility that 2,8-DHA crystals were the cause of the reduced renal function was suggested. As experiments in rats confirmed that 2,8-DHA crystals cause kidney toxicity, even in the absence of calculus, the patient was started on medication for hyperuricemia, which also controls 2,8-DHA biosynthesis. In this case, the diagnosis was made and treatment commenced on the basis of a report from a clinical laboratory regarding the crystals, and is an example whereby analysis of urinary sediment contributed to clinical management.

Journal

• Japanese Journal of Medical Technology

  Japanese Journal of Medical Technology 65 (6), 695-699, 2016

  Japanese Association of Medical Technologists

Keywords

• 2,8-dihydroxyadenine crystals; 2,8-DHA
• adenine phoshoribosyl transferase (APRT) deficiency
• urinary calculi
• genetic analysis
• salts crystal cast

Details

• CRID: 1390282680718456960
• NII Article ID: 130005289378
• DOI: 10.14932/jamt.16-13
• ISSN: 21885346
• ISSN: 09158669
• Text Lang: ja
• Data Source:
  • JaLC
  • CiNii Articles
• Abstract License Flag: Disallowed