Leidi Antonio, Pisaturo Marisa, Fumeaux Thierry
Department of Internal Medicine, GHOL-Nyon Hospital, Chemin Monastier 10, 1260, Nyon, Switzerland.
Department of Internal Medicine and Critical Care Medicine, GHOL-Nyon Hospital, Chemin Monastier 10, 1260, Nyon, Switzerland.
J Med Case Rep. 2019 Aug 10;13(1):248. doi: 10.1186/s13256-019-2185-6.
Hyperammonemia is a common cause of metabolic encephalopathy, mainly related to hepatic cirrhosis. Numerous nonhepatic etiologies exist but they are infrequent and not well known, thus, leading to misdiagnosis and inadequate care. Electroencephalography has a proven diagnostic and prognostic role in comatose patients. Burst suppression is a preterminal pattern found in deep coma states and is rarely associated with metabolic causes.
We report the case of an 81-year-old Caucasian man presenting with rapidly progressive somnolence and mutism. Soon after his arrival in our hospital, he developed profound coma. A comprehensive diagnostic workup was unremarkable except for admission electroencephalography showing diffuse slowing of cerebral activity with an intermittent pattern of burst suppression. He was admitted to our intensive care unit for supportive care where malnutrition-related hyperammonemia was diagnosed. His clinical course was spontaneously favorable and follow-up electroencephalography demonstrated normal cerebral activity.
Nonhepatic hyperammonemia is a rare and potentially reversible cause of encephalopathy. Ammonia level measurement should be part of the diagnostic workup in patients with unexplained coma, particularly in the setting of nutritional deficiencies or nutritional supply. Detection of diffuse and nonspecific mild to moderate slowing of cerebral activity (theta-delta ranges) on electroencephalography is common. In contrast, to the best of our knowledge, burst suppression has never been described in association with hyperammonemia.
高氨血症是代谢性脑病的常见病因，主要与肝硬化有关。存在许多非肝脏病因，但它们并不常见且鲜为人知，因此会导致误诊和护理不当。脑电图在昏迷患者中具有已证实的诊断和预后作用。爆发抑制是在深度昏迷状态下发现的终末期模式，很少与代谢原因相关。
我们报告了一例81岁的白种男性患者，表现为快速进展的嗜睡和缄默症。他入院后不久就陷入了深度昏迷。全面的诊断检查除了入院时脑电图显示脑活动弥漫性减慢并伴有间歇性爆发抑制模式外，并无异常。他被收入我们的重症监护病房进行支持治疗，在此期间诊断出与营养不良相关的高氨血症。他的临床病程自发好转，后续脑电图显示脑活动正常。
非肝脏性高氨血症是一种罕见且可能可逆的脑病病因。对于原因不明的昏迷患者，尤其是存在营养缺乏或营养供给问题的患者，氨水平测量应作为诊断检查的一部分。脑电图检测到脑活动弥漫性、非特异性的轻度至中度减慢（θ波-δ波范围）很常见。相比之下，据我们所知，爆发抑制从未被描述与高氨血症相关。
