Tacrolimus Toxicity Induced by Nirmatrelvir/Ritonavir in a Renal Transplant Recipient Managed With Phenytoin: A Case Report and Literature Review

IF 0.8 4区医学 Q4 IMMUNOLOGY

Transplantation proceedings Pub Date : 2025-09-01 DOI:10.1016/j.transproceed.2025.06.019

Ching-Yu Wang , Cheng-Hsu Chen , Shang-Feng Tsai

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引用次数: 0

Abstract

Introduction

The COVID-19 pandemic has led to widespread use of nirmatrelvir/ritonavir in high-risk populations. Ritonavir, a strong CYP3A4 inhibitor, can significantly increase tacrolimus levels, causing toxicity in transplant recipients. This report presents a case of nirmatrelvir/ritonavir -induced tacrolimus toxicity in a kidney transplant patient, successfully managed with phenytoin, a CYP3A4 inducer.

Case report

A 63-year-old male kidney transplant recipient experienced malaise and hand tremors after nirmatrelvir/ritonavir treatment for mild COVID-19. Lab tests revealed ac1ute kidney injury and supratherapeutic tacrolimus levels (>60 ng/mL). Tacrolimus was discontinued, and hydration was initiated. Persistent toxicity required phenytoin, leading to rapid improvement. A renal biopsy showed no toxicity, and the patient was discharged without complications.

Discussion

Among 51 reported cases of nirmatrelvir/ritonavir -induced tacrolimus toxicity, 13 used CYP3A4 inducers. This case highlights phenytoin's efficacy in reducing toxicity and protecting renal function. Timely initiation with a loading dose is crucial for optimal outcomes.

Conclusion

Early recognition and prompt management with hydration and CYP3A4 inducers, such as phenytoin, are essential in mitigating nirmatrelvir/ritonavir -associated tacrolimus toxicity.

查看原文本刊更多论文

苯妥英治疗肾移植受者尼马特利韦/利托那韦致他克莫司毒性：1例报告及文献复习。

2019冠状病毒病大流行导致高危人群广泛使用尼马特利韦/利托那韦。利托那韦是一种强效CYP3A4抑制剂，可显著增加他克莫司水平，对移植受者造成毒性。本报告报告了一例尼马特利韦/利托那韦诱导的肾移植患者他克莫司毒性，并成功地用苯妥英（一种CYP3A4诱导剂）进行了治疗。病例报告：一名63岁男性肾移植受者在尼马特利韦/利托那韦治疗轻度COVID-19后出现不适和手部震颤。实验室检查显示急性肾损伤和超治疗性他克莫司水平（bbb60 ng/mL）。停用他克莫司，开始水合治疗。持续的毒性需要苯妥英，导致迅速改善。肾活检显示无毒性，患者无并发症出院。讨论：在51例报告的尼马特利韦/利托那韦引起的他克莫司毒性中，13例使用了CYP3A4诱导剂。本病例强调了苯妥英在降低毒性和保护肾功能方面的功效。及时开始与负荷剂量是最佳结果的关键。结论：早期识别和及时处理水合作用和CYP3A4诱导剂，如苯妥英，对于减轻尼马特利韦/利托那韦相关的他克莫司毒性至关重要。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Transplantation proceedings 医学-免疫学

CiteScore

1.70

自引率

0.00%

发文量

502

审稿时长

60 days

期刊介绍： Transplantation Proceedings publishes several different categories of manuscripts, all of which undergo extensive peer review by recognized authorities in the field prior to their acceptance for publication. The first type of manuscripts consists of sets of papers providing an in-depth expression of the current state of the art in various rapidly developing components of world transplantation biology and medicine. These manuscripts emanate from congresses of the affiliated transplantation societies, from Symposia sponsored by the Societies, as well as special Conferences and Workshops covering related topics. Transplantation Proceedings also publishes several special sections including publication of Clinical Transplantation Proceedings, being rapid original contributions of preclinical and clinical experiences. These manuscripts undergo review by members of the Editorial Board. Original basic or clinical science articles, clinical trials and case studies can be submitted to the journal?s open access companion title Transplantation Reports.