Redant S, Empain A, Mugisha A, Kamgang P, Attou R, Honoré P M, De Bels D
Department of Intensive Care, Université Libre de Bruxelles (ULB), CHU Brugmann-Brugmann University Hospital, 4, Place Arthur Van Gehuchten, 1020, Brussels, Belgium.
Department of Metabolic Diseases, Hôpital universitaire des enfants reine Fabiola, Université Libre de Bruxelles (ULB), Brussels, Belgium.
Ann Intensive Care. 2021 Jan 6;11(1):2. doi: 10.1186/s13613-020-00797-y.
Hyperammonemia caused by a disorder of the urea cycle is a rare cause of metabolic encephalopathy that may be underdiagnosed by the adult intensivists because of its rarity. Urea cycle disorders are autosomal recessive diseases except for ornithine transcarbamylase deficiency (OTCD) that is X-linked. Optimal treatment is crucial to improve prognosis. Main body We systematically reviewed cases reported in the literature on hyperammonemia in adulthood. We used the US National Library of Medicine Pubmed search engine since 2009. The two main causes are ornithine transcarbamylase deficiency followed by type II citrullinemia. Diagnosis by the intensivist remains very challenging therefore delaying treatment and putting patients at risk of fatal cerebral edema. Treatment consists in adapted nutrition, scavenging agents and dialysis. As adults are more susceptible to hyperammonemia, emergent hemodialysis is mandatory before referral to a reference center if ammonia levels are above 200 µmol/l as the risk of cerebral edema is then above 55%. Definitive therapy in urea cycle abnormalities is liver transplantation.
Awareness of urea cycle disorders in adults intensive care units can optimize early management and accordingly dramatically improve prognosis. By preventing hyperammonemia to induce brain edema and herniation leading to death.
尿素循环障碍引起的高氨血症是代谢性脑病的罕见病因，因其罕见，成人重症监护医生可能对其诊断不足。除X连锁的鸟氨酸转氨甲酰酶缺乏症（OTCD）外，尿素循环障碍是常染色体隐性疾病。最佳治疗对改善预后至关重要。
我们系统回顾了自2009年以来文献报道的成人高氨血症病例。我们使用了美国国立医学图书馆的PubMed搜索引擎。两个主要病因是鸟氨酸转氨甲酰酶缺乏症，其次是II型瓜氨酸血症。重症监护医生进行诊断仍然非常具有挑战性，因此会延误治疗，使患者面临致命脑水肿的风险。治疗包括调整营养、使用清除剂和透析。由于成年人更容易发生高氨血症，如果氨水平高于200µmol/L，在转诊至参考中心之前必须进行紧急血液透析，因为此时脑水肿的风险高于55%。尿素循环异常的确定性治疗是肝移植。
成人重症监护病房对尿素循环障碍的认识可以优化早期管理，从而显著改善预后。通过预防高氨血症诱发脑水肿和脑疝导致死亡。
