Chang Nathan, Mariano Karley, Ganesan Lakshmi, Cooper Holly, Kuo Kevin
Department of Pediatric Critical Care Medicine, Lucile Packard Children's Hospital Stanford, Palo Alto, CA, USA.
Department of Pediatric Nephrology, Lucile Packard Children's Hospital Stanford, Palo Alto, CA, USA.
J Med Case Rep. 2020 Oct 10;14(1):183. doi: 10.1186/s13256-020-02536-0.
Disorders of water and sodium balance can occur after brain injury. Prolonged polyuria resulting from central diabetes insipidus and cerebral salt wasting complicated by gradient washout and a type of secondary nephrogenic diabetes insipidus, however, has not been described previously, to the best of our knowledge. We report an unusual case of an infant with glioblastoma who, after tumor resection, was treated for concurrent central diabetes insipidus and cerebral salt wasting complicated by secondary nephrogenic diabetes insipidus.
A 5-month-old Hispanic girl was found to have a large, hemorrhagic, suprasellar glioblastoma causing obstructive hydrocephalus. Prior to mass resection, she developed central diabetes insipidus. Postoperatively, she continued to have central diabetes insipidus and concurrent cerebral salt wasting soon after. She was managed with a vasopressin infusion, sodium supplementation, fludrocortisone, and urine output replacements. Despite resolution of her other major medical issues, she remained in the pediatric intensive care unit for continual and aggressive management of water and sodium derangements. Starting on postoperative day 18, her polyuria began increasing dramatically and did not abate with increasing vasopressin. Nephrology was consulted. Her blood urea nitrogen was undetectable during this time, and it was thought that she may have developed a depletion of inner medullary urea and osmotic gradient: a "gradient washout." Supplemental dietary protein was added to her enteral nutrition, and her fluid intake was decreased. Within 4 days, her blood urea nitrogen increased, and her vasopressin and fluid replacement requirements significantly decreased. She was transitioned soon thereafter to subcutaneous desmopressin and transferred out of the pediatric intensive care unit.
Gradient washout has not been widely reported in humans, although it has been observed in the mammalian kidneys after prolonged polyuria. Although not a problem with aquaporin protein expression or production, gradient washout causes a different type of secondary nephrogenic diabetes insipidus because the absence of a medullary gradient impairs water reabsorption. We report a case of an infant who developed complex water and sodium imbalances after brain injury. Prolonged polyuria resulting from both water and solute diuresis with low enteral protein intake was thought to cause a urea gradient washout and secondary nephrogenic diabetes insipidus. The restriction of fluid replacements and supplementation of enteral protein appeared adequate to restore the renal osmotic gradient and efficacy of vasopressin.
脑损伤后可出现水和钠平衡紊乱。据我们所知，中枢性尿崩症和脑性盐耗综合征合并梯度冲洗及一种继发性肾性尿崩症导致的长期多尿此前尚未见报道。我们报告一例患有胶质母细胞瘤的婴儿的罕见病例，该婴儿在肿瘤切除后，因并发中枢性尿崩症和脑性盐耗综合征合并继发性肾性尿崩症而接受治疗。
一名5个月大的西班牙裔女孩被发现患有一个巨大的、出血性的鞍上胶质母细胞瘤，导致梗阻性脑积水。在肿块切除术前，她出现了中枢性尿崩症。术后，她很快继续出现中枢性尿崩症，并同时并发脑性盐耗综合征。她接受了血管加压素输注、补钠、氟氢可的松及尿量替代治疗。尽管她的其他主要医疗问题得到了解决，但她仍留在儿科重症监护病房，接受水和钠紊乱的持续积极治疗。从术后第18天开始，她的多尿症状急剧加重，且随着血管加压素剂量增加症状并未减轻。于是咨询了肾脏病科。在此期间她的血尿素氮检测不到，推测她可能发生了髓质内尿素和渗透梯度的耗竭：即“梯度冲洗”。在她的肠内营养中添加了补充性膳食蛋白质，并减少了液体摄入量。4天内，她的血尿素氮升高，血管加压素和液体替代需求显著降低。此后不久，她转为皮下注射去氨加压素，并转出了儿科重症监护病房。
尽管在长期多尿后的哺乳动物肾脏中观察到了梯度冲洗，但在人类中尚未广泛报道。虽然这不是水通道蛋白表达或产生的问题，但梯度冲洗会导致一种不同类型的继发性肾性尿崩症，因为髓质梯度的缺失会损害水的重吸收。我们报告了一例婴儿在脑损伤后出现复杂的水和钠失衡的病例。水和溶质利尿以及低肠内蛋白质摄入导致的长期多尿被认为引起了尿素梯度冲洗和继发性肾性尿崩症。限制液体替代和补充肠内蛋白质似乎足以恢复肾脏渗透梯度和血管加压素的疗效。
