背景:急性脑病,虽然在急诊科常见的介绍,通常是由多种新陈代谢引起的,血管,传染性,结构,或精神病病因。在代谢原因中,高氨血症是比较常见的,通常发生在肝硬化或肝功能障碍的情况下。然而,非肝硬化性高氨血症是一种罕见的病例,对临床医生提出了独特的挑战.
方法:在这里,我们报告了一例50岁的白人女性化疗后有膀胱癌病史的罕见病例,根治性膀胱切除术,和回盲部改道,他们出现了严重的精神状态改变,战斗性,和3天尿量减少的病史。她的实验室检查值得注意的是高氨血症高达289μmol/L,低钾血症,和高氯血症非阴离子间隙代谢性酸中毒;她的肝功能检查正常。尿培养显示屎肠球菌阳性。计算机断层扫描成像显示完整的回肠尿路改道伴慢性回肠结石。服用适当的抗生素后,乳果糖,还有柠檬酸钾,她的脑病迅速消退,高氨血症显著减少。她的高氯血症代谢性酸中毒持续存在,但她的低钾血症已经解决了.
结论:这种情况是尿路改道的独特后果之一。尿路上皮组织通常对尿溶质是不可渗透的。然而,当使用肠段时,发生溶质的异常吸收,包括将尿氯化物换成血清碳酸氢盐,导致持续性高血非阴离子间隙代谢性酸中毒。此外,产生尿素的生物体中氨的过量产生可导致血液中的异常吸收和随后的肝代谢能力过饱和,从而导致高氨血症性脑病。虽然这是一个罕见的案例,迅速识别和治疗这些代谢异常是至关重要的,以防止严重的中枢神经系统并发症,如改变的精神状态,昏迷,甚至是尿路改道患者的死亡。
BACKGROUND: Acute encephalopathy, while a common presentation in the emergency department, is typically caused by a variety of metabolic, vascular, infectious, structural, or psychiatric etiologies. Among metabolic causes, hyperammonemia is relatively common and typically occurs in the setting of cirrhosis or liver dysfunction. However, noncirrhotic hyperammonemia is a rare occurrence and poses unique challenges for clinicians.
METHODS: Here we report a rare
case of a 50-year-old Caucasian female with history of bladder cancer status post chemotherapy, radical cystectomy, and ileocecal diversion who presented to the emergency department with severe altered mental status, combativeness, and a 3-day history of decreased urine output. Her laboratory tests were notable for hyperammonemia up to 289 μmol/L, hypokalemia, and hyperchloremic nonanion gap metabolic acidosis; her liver function tests were normal. Urine cultures were positive for Enterococcus faecium. Computed tomography imaging showed an intact ileoceal urinary diversion with chronic ileolithiasis. Upon administration of appropriate antibiotics, lactulose, and potassium citrate, she experienced rapid resolution of her encephalopathy and a significant reduction in hyperammonemia. Her hyperchloremic metabolic acidosis persisted, but her hypokalemia had resolved.
CONCLUSIONS: This
case is an example of one of the unique consequences of urinary diversions. Urothelial tissue is typically impermeable to urinary solutes. However, when bowel segments are used, abnormal absorption of solutes occurs, including exchange of urinary chloride for serum bicarbonate, leading to a persistent hyperchloremic nonanion gap metabolic acidosis. In addition, overproduction of ammonia from urea-producing organisms can lead to abnormal absorption into the blood and subsequent oversaturation of hepatic metabolic capacity with consequent hyperammonemic encephalopathy. Although this is a rare
case, prompt identification and treatment of these metabolic abnormalities is critical to prevent severe central nervous system complications such as altered mental status, coma, and even death in patients with urinary diversions.