Raza Hafiz Muhammad Ali, Ibrahim Atif, Talwar Manish, Balaraman Vasanthi, Bhalla Anshul, Wall Barry M, Cossey L Nicholas
Department of Medicine, North Mississippi Medical Center (NMMC), Tupelo, MS, USA.
Department of Nephrology, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA.
Am J Case Rep. 2025 Jun 6;26:e946972. doi: 10.12659/AJCR.946972.
BACKGROUND The renal condition known as 2,8-dihydroxyadeninuria is an autosomal recessive disorder caused by adenine phosphoribosyl transferase (APRT) deficiency, which most commonly manifests as nephrolithiasis. APRT deficiency has also led to the development of chronic kidney disease and end-stage kidney disease in the absence of nephrolithiasis and has also been shown to recur following kidney transplantation. CASE REPORT This report aims to highlight the diagnostic and therapeutic challenges associated with APRT deficiency by presenting 2 patients with end-stage kidney disease who developed 2,8-dihydroxyadenine (DHA) crystalline nephropathy early in their post-transplant course. Neither patient had been diagnosed with APRT deficiency prior to transplantation, and one lacked a history of nephrolithiasis. Allograft biopsies revealed DHA crystal deposition with acute tubular injury, and genetic analysis confirmed APRT deficiency. Management included xanthine oxidase inhibitors, a low-purine diet, and modification of the immunosuppressive regimen with belatacept to reduce long-term tubulointerstitial injury. Both patients achieved stable long-term allograft function at 2 years, with follow-up biopsies at 1 year, showing a significant decrease in crystal deposition. CONCLUSIONS This case report underscores the importance of early recognition of APRT deficiency through timely biopsy, crystal identification, and genetic testing to guide effective treatment and prevent irreversible damage. It highlights the need for heightened clinical suspicion and tailored post-transplant management strategies in patients with recurrent DHA nephropathy.
背景 被称为2,8 - 二羟基腺嘌呤尿症的肾脏疾病是一种由腺嘌呤磷酸核糖转移酶（APRT）缺乏引起的常染色体隐性疾病，最常见的表现为肾结石。APRT缺乏在无肾结石的情况下也会导致慢性肾病和终末期肾病的发生，并且在肾移植后也会复发。病例报告 本报告旨在通过介绍2例终末期肾病患者来突出与APRT缺乏相关的诊断和治疗挑战，这2例患者在移植后的早期病程中发生了2,8 - 二羟基腺嘌呤（DHA）结晶性肾病。2例患者在移植前均未被诊断出APRT缺乏，其中1例没有肾结石病史。移植肾活检显示DHA晶体沉积伴急性肾小管损伤，基因分析证实为APRT缺乏。治疗包括使用黄嘌呤氧化酶抑制剂、低嘌呤饮食以及将免疫抑制方案改为使用贝拉西普以减少长期的肾小管间质损伤。2例患者在2年时均实现了移植肾长期稳定功能，在1年时进行的随访活检显示晶体沉积显著减少。结论 本病例报告强调了通过及时活检、晶体鉴定和基因检测来早期识别APRT缺乏以指导有效治疗并防止不可逆损伤的重要性。它突出了对于复发性DHA肾病患者提高临床怀疑度和制定个体化移植后管理策略的必要性。
