El Beltagi Ahmed, Norbash Alexander, Vattoth Surjith
Department of Radiology, Al-Sabah Hospital, Kuwait
Department of Radiology, Boston University School of Medicine, USA.
Neuroradiol J. 2015 Oct;28(5):523-8. doi: 10.1177/1971400915609340. Epub 2015 Oct 6.
Gitelman syndrome is an autosomal recessive renal tubular disorder characterized by hypokalemic metabolic alkalosis, hypomagnesemia and hypocalciuria. The syndrome is caused by a defective thiazide-sensitive sodium chloride co-transporter in the distal convoluted tubules of the kidneys. Gitelman syndrome could be confused with Bartter syndrome; the main differentiating feature is the presence of low urinary calcium excretion in the former. Descriptions of neuroradiological imaging findings associated with Gitelman syndrome are very scarce in the literature and include basal ganglia calcification, idiopathic intracranial hypertension and sclerochoroidal calcification. Cauda equina syndrome-like presentation has been reported, but without any corresponding imaging findings on lumbar spine MRI. We report a 13-year-old male with Gitelman syndrome who presented with altered mental status following a fall and scalp laceration and unremarkable brain CT, followed during hospitalization by somnolence and seizures. Metabolically the patient demonstrated hypokalemia and hypomagnesemia. MRI demonstrated features of encephalopathy including predominantly right-sided cerebral hemispheric signal abnormality and cytotoxic edema, with bilateral symmetric involvement of the thalami, midbrain tegmentum and tectum and cerebellar dentate nuclei. MRI after five months obtained during a later episode of encephalopathy showed resolution of the signal abnormalities with setting in of brain atrophy and also areas of newly developed cytotoxic edema in the left thalamus, bilateral dorsal midbrain and right greater than left dentate nuclei. The described abnormalities, either recurrent or in isolation, have not previously been published in patients with Gitelman syndrome. We believe that the findings are due to alteration of respiratory chain function secondary to the metabolic derangement and hence have a similar imaging appearance as encephalopathy related to mitochondrial cytopathy or metabolic encephalopathy.
吉特曼综合征是一种常染色体隐性遗传性肾小管疾病，其特征为低钾血症性代谢性碱中毒、低镁血症和低钙尿症。该综合征是由肾脏远曲小管中对噻嗪类敏感的氯化钠共转运体缺陷引起的。吉特曼综合征可能会与巴特综合征相混淆；主要的鉴别特征是前者存在低尿钙排泄。文献中关于吉特曼综合征相关神经放射影像学表现的描述非常少见，包括基底节钙化、特发性颅内高压和脉络膜巩膜钙化。曾有马尾综合征样表现的报道，但腰椎MRI未发现相应影像学表现。我们报告一名13岁男性吉特曼综合征患者，其在跌倒和头皮裂伤后出现精神状态改变，脑部CT检查无异常，住院期间出现嗜睡和癫痫发作。代谢方面，患者表现为低钾血症和低镁血症。MRI显示脑病特征，主要为右侧大脑半球信号异常和细胞毒性水肿，丘脑、中脑被盖和顶盖以及小脑齿状核呈双侧对称受累。在后来一次脑病发作期间五个月后进行的MRI显示信号异常消失，出现脑萎缩，同时左侧丘脑、双侧中脑背侧和右侧大于左侧的齿状核出现新的细胞毒性水肿区域。所描述的这些异常，无论是反复出现还是单独出现，此前在吉特曼综合征患者中均未发表过。我们认为这些发现是由于代谢紊乱继发呼吸链功能改变所致，因此具有与线粒体细胞病或代谢性脑病相关的脑病相似的影像学表现。
