Abstract:
Methylmalonic acidemia cblB type (MMA cblB) is an autosomal recessive inborn error of amino acid metabolism that results in impaired synthesis of adenosylcobalamin, a cofactor of methylmalonyl-CoA mutase. It presents with episodes of coma, vomiting, hypotonia, metabolic acidosis, and hyperammonemia. End-stage kidney disease is a long-term complication. Treatments include vitamin B12 supplementation, L-carnitine, and a low-protein diet. Liver, kidney, or combined liver-kidney transplantations are promising options, but they are not without complications. We report a patient suffering from MMA cblB who developed end-stage kidney disease at 18 years of age. Kidney transplantation allowed him to recover normal kidney function and good metabolic control. Unfortunately, after two decades, he developed non-Hodgkin lymphoma and severe chemotherapy toxicity which led to his death. The risk of lymphoproliferative diseases is known to increase after solid organ transplantation. However, in MMA, factors including mitochondrial dysfunction and oncometabolites, may further increase the risk of malignancy and drug toxicity. Our report highlights the importance of considering the increased risk of cancer in long-term follow-up of MMA cblB patients, especially after solid organ transplantation. Moreover, when chemotherapy is needed, the increased risk of toxicity and metabolic decompensation should be considered and monitored.
摘要:
甲基丙二酸血症cblB型(MMAcblB)是一种常染色体隐性遗传性先天性氨基酸代谢错误,导致腺苷钴胺合成受损,甲基丙二酰辅酶A变位酶的辅因子。它表现为昏迷发作,呕吐,低张力,代谢性酸中毒,和高氨血症。终末期肾病是一种长期并发症。治疗包括补充维生素B12,左旋肉碱,低蛋白饮食.肝脏,肾,或肝肾联合移植是有希望的选择,但它们并非没有并发症。我们报告了一名患有MMAcblB的患者,该患者在18岁时发展为终末期肾脏疾病。肾移植使他恢复正常的肾功能和良好的代谢控制。不幸的是,二十年后,他患有非霍奇金淋巴瘤和严重的化疗毒性,导致他死亡。已知淋巴增生性疾病的风险在实体器官移植后增加。然而,在MMA中,因素包括线粒体功能障碍和细胞代谢产物,可能会进一步增加恶性肿瘤和药物毒性的风险。我们的报告强调了在MMAcblB患者的长期随访中考虑癌症风险增加的重要性,尤其是实体器官移植后。此外,当需要化疗时,应考虑并监测毒性和代谢失代偿风险的增加.