Division of Medical Toxicology, Henry J.N. Taub Department of Emergency Medicine, Baylor College of Medicine, 1504 Ben Taub Loop, Houston, TX, 77030, USA.
Division of Medical Toxicology, Ronald O. Perelman Department of Emergency Medicine, NYU School of Medicine, New York, NY, USA.
J Med Toxicol. 2021 Jan;17(1):70-74. doi: 10.1007/s13181-020-00802-7. Epub 2020 Aug 12.
Although hemodialysis is recommended for patients with severe metformin-associated lactic acidosis (MALA), the amount of metformin removed by hemodialysis is poorly documented. We analyzed endogenous clearance and hemodialysis clearance in a patient with MALA.
A 62-year-old man with a history of type II diabetes mellitus presented after several days of vomiting and diarrhea and was found to have acute kidney injury (AKI) and severe acidemia. Initial serum metformin concentration was 315.34 μmol/L (40.73 μg/mL) (typical therapeutic concentrations 1-2 μg/mL). He underwent 6 h of hemodialysis. We collected hourly whole blood, serum, urine, and dialysate metformin concentrations. Blood, urine, and dialysate samples were analyzed, and clearances were determined using standard pharmacokinetic calculations.
The total amount of metformin removed by 6 h of hemodialysis was 888 mg, approximately equivalent to one therapeutic dose. Approximately 142 mg of metformin was cleared in the urine during this time. His acid-base status and creatinine improved over the following days. No further hemodialysis was required.
We report a case of MALA likely secondary to AKI and severe volume depletion. The patient improved with supportive care, sodium bicarbonate, and hemodialysis. Analysis of whole blood, serum, urine, and dialysate concentrations showed limited efficacy of hemodialysis in the removal of metformin from blood, contrary to previously published data. Despite evidence of acute kidney injury, a relatively large amount of metformin was eliminated in the urine while the patient was undergoing hemodialysis. These data suggest that clinical improvement is likely due to factors besides removal of metformin.
尽管对于严重的二甲双胍相关性乳酸性酸中毒（MALA）患者推荐进行血液透析治疗，但血液透析清除二甲双胍的量却记录不佳。我们分析了一位 MALA 患者的内源性清除率和血液透析清除率。
一位 62 岁男性，有 2 型糖尿病病史，因数日呕吐和腹泻就诊，被诊断为急性肾损伤（AKI）和严重酸中毒。初始血清二甲双胍浓度为 315.34 μmol/L（40.73 μg/mL）（典型治疗浓度为 1-2 μg/mL）。他接受了 6 小时的血液透析。我们每小时采集全血、血清、尿液和透析液中的二甲双胍浓度。对血液、尿液和透析液样本进行分析，并使用标准药代动力学计算确定清除率。
6 小时血液透析清除的二甲双胍总量约为 888mg，约相当于一个治疗剂量。在此期间，约有 142mg 的二甲双胍从尿液中清除。他的酸碱状态和肌酐在接下来的几天中得到改善，之后无需再进行血液透析。
我们报告了一例可能由 AKI 和严重容量不足引起的 MALA 病例。患者通过支持性治疗、碳酸氢钠和血液透析得到改善。对全血、血清、尿液和透析液浓度的分析表明，血液透析对二甲双胍从血液中的清除效果有限，与之前发表的数据相反。尽管存在急性肾损伤的证据，但患者在进行血液透析时，仍有相对大量的二甲双胍从尿液中排出。这些数据表明，临床改善可能不仅仅是由于二甲双胍的清除。
