Non-urate transporter 1, non-glucose transporter member 9-related renal hypouricemia and acute renal failure accompanied by hyperbilirubinemia after anaerobic exercise: a case report
Non-urate transporter 1, non-glucose transporter member 9-related renal hypouricemia and acute renal failure accompanied by hyperbilirubinemia after anaerobic exercise: a case report
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DOI：
10.1186/s12882-019-1618-1
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发表时间：
2019-11-26
期刊：
影响因子：
2.3
通讯作者：
Sohara, Eisei
中科院分区：
文献类型：
--
作者：
Furuto, Yoshitaka;Kawamura, Mariko;Sohara, Eisei
背景 肾性低尿酸血症（RHUC）是一种遗传性异质性疾病，由肾近端肾小管细胞中的尿酸盐重吸收转运蛋白缺陷引起。无氧运动可能会导致 RHUC 患者出现急性肾损伤，但这种损伤并非由劳力性横纹肌溶解症引起；它被称为无氧运动后伴有严重腰痛和斑片状肾缺血的急性肾功能衰竭（ALPE）。 RHUC 是 ALPE 最重要的危险因素。然而，RHUC 患者发生 ALPE 的机制尚未阐明。目前已知负责 RHUC 的基因是 SLC22A12 和 SLC2A9。病例介绍 一名 37 岁男性在运动后出现腰部疼痛。尽管从出生起就有健康的体质，但生化检查却发现低尿酸血症，每次健康检查时尿酸（UA）水平始终<1 mg/dL。我们检测到急性肾损伤，肌酐 (Cr) 水平为 4.1 mg/dL，胆红素升高；因此，病人住院了。计算机断层扫描显示没有肾结石，但发现双侧肾肿胀。磁共振成像检测到楔形病变，表明双侧肾缺血。钠和UA的排泄分数值分别为0.61和50.5%。尿液显微镜检查显示没有肾小管损伤。患者的姐姐患有低尿酸血症。该患者被诊断患有 ALPE。卧床休息、补液和营养治疗改善了肾功能和胆红素水平，患者于第 5 天出院。ALPE 发病后约 1 个月，患者的 Cr、UA 和 TB 水平分别为 0.98、0.8 和 0.9 mg/dL。由于低尿酸血症和家族史，我们怀疑家族性 RHUC，并进行了基因检测，但没有找到导致 RHUC 的典型基因。家人反对进行全面的基因分析。结论 据我们所知，这是首例 ALPE 合并高胆红素血症的报道。 RHUC 患者运动诱发的急性肾损伤中，血红素加氧酶 1 激活可能导致胆红素水平升高；这种现象提示肾缺血再灌注损伤。可能存在编码尿酸盐转运蛋白的新致病基因，其鉴定将有助于阐明尿酸盐转运机制。
Background Renal hypouricemia (RHUC) is an inherited heterogenous disorder caused by faulty urate reabsorption transporters in the renal proximal tubular cells. Anaerobic exercise may induce acute kidney injury in individuals with RHUC that is not caused by exertional rhabdomyolysis; it is called acute renal failure with severe loin pain and patchy renal ischemia after anaerobic exercise (ALPE). RHUC is the most important risk factor for ALPE. However, the mechanism of onset of ALPE in patients with RHUC has not been elucidated. The currently known genes responsible for RHUC are SLC22A12 and SLC2A9. Case presentation A 37-year-old man presented with loin pain after exercising. Despite having a healthy constitution from birth, biochemical examination revealed hypouricemia, with a uric acid (UA) level of < 1 mg/dL consistently at every health check. We detected acute kidney injury, with a creatinine (Cr) level of 4.1 mg/dL, and elevated bilirubin; hence, the patient was hospitalized. Computed tomography revealed no renal calculi, but bilateral renal swelling was noted. Magnetic resonance imaging detected cuneiform lesions, indicating bilateral renal ischemia. Fractional excretion values of sodium and UA were 0.61 and 50.5%, respectively. Urinary microscopy showed lack of tubular injury. The patient's older sister had hypouricemia. The patient was diagnosed with ALPE. Treatment with bed rest, fluid replacement, and nutrition therapy improved renal function and bilirubin levels, and the patient was discharged on day 5. Approximately 1 month after onset of ALPE, his Cr, UA, and TB levels were 0.98, 0.8, and 0.9 mg/dL, respectively. We suspected familial RHUC due to the hypouricemia and family history and performed genetic testing but did not find the typical genes responsible for RHUC. A full genetic analysis was opposed by the family. Conclusions To the best of our knowledge, this is the first report of ALPE with hyperbilirubinemia. Bilirubin levels may become elevated as a result of heme oxygenase-1 activation, occurring in exercise-induced acute kidney injury in patients with RHUC; this phenomenon suggests renal ischemia-reperfusion injury. A new causative gene coding for a urate transporter may exist, and its identification would be useful to clarify the urate transport mechanism.