Korean J Transplant.  2022 Nov;36(Supple 1):S242. 10.4285/ATW2022.F-3829.

Successful eculizumab rescue therapy of atypical hemolytic uremic syndrome in kidney transplant recipient: a case report

• Min EK
• Kim HJ
• Kim S
• Lim BJ
• Kim JS
• Han SH
• Huh KH

• KMID: 2535459
• DOI: http://doi.org/10.4285/ATW2022.F-3829

Abstract

Atypical hemolytic uremic syndrome (aHUS) is a form of thrombotic microangiopathy (TMA) that results in end-stage renal disease (ESRD) in up to half of patients without prompt treatment. Patients with aHUS often have predisposing dysfunction related to complement pathway where continuous activation of complement proteins is triggered by various events, including organ transplantation. Use of eculizumab, a terminal complement protein blockage, has been reported in several studies to be effective in posttransplant TMA. This is a report of aHUS in kidney transplant recipient which was successfully rescued with early use of eculizumab. The patient was 32-year-old male with ESRD from IgA nephropathy and the donor was his 60-yearold mother. Cross matching tests were all negative and the graft showed immediate good function. On postoperative day (POD) 3, thrombocytopenia, anemia without bleeding, and elevated lactate dehydrogenase made clinical diagnosis of TMA. Plasma exchange (PE) was immediately initiated along with tacrolimus withdrawal, and differential diagnosis of TMA and biopsy were performed. Despite 10 PE sessions, hematological response was only partial and renal dysfunction was persistent, prompting initiation of eculizumab (900 mg weekly) treatment from POD 18 under suspicion of aHUS (Fig. 1). Biopsy confirmed TMA without evidence of rejection. NGS reported gene mutations classified to variant of unknown significance in coagulation-as-sociated genes. Laboratory data gradually improved during three doses of eculizumab, and the patient was discharged on POD 33 with serum creatinine level of 1.82 mg/dL (Fig. 1). Total 16 doses of eculizumab were administered for 27 weeks. At last fol-low-up on posttransplant 27 months, transplanted kidney was maintaining its functioning with serum creatinine level of 1.83mg/dL without proteinuria. De novo TMA after kidney transplantation can be caused by sustained activation of complement pathway and that early eculizumab treatment might be important in successful treatment of aHUS that is refractory to conven-tional PE.