Sajith J, Ditchfield A, Katifi H A
Department of Adult Medicine, Queen Elizabeth Hospital, Woolwich, London, UK.
BMC Neurol. 2006 Sep 10;6:33. doi: 10.1186/1471-2377-6-33.
Extrapontine myelinolysis presenting with extra pyramidal features suggestive of parkinsonism may be a challenging clinical syndrome. Clinicians should maintain their vigilance while correcting electrolyte imbalances, especially with associated co-morbidity.
A 41-year-old woman presented with acute parkinsonism like features while on a holiday. This followed slow correction of hyponatraemia after repeated vomiting. MRI changes were suggestive of Extrapontine myelinolysis(EPM). This case is at variance with four previous cases reported in the medical literature in that the patient made a full clinical recovery and the MR changes resolved with symptomatic support alone.
Extrapontine myelinolysis could make a complete recovery with symptomatic support alone. During hyponatraemia correction, rapid osmotic shifts of fluid that cause hypernatremia, causes myelinolysis rather than absolute serum sodium level. Even gradual correction of hyponatraemia can produce myelinolysis, especially with pre-existing malnourishment, alcoholism, drug misuse, Addison's disease and immuno-suppression. Pallidial sparing is typical of EPM in MRI scans.
表现为提示帕金森综合征的锥体外系特征的脑桥外髓鞘溶解症可能是一种具有挑战性的临床综合征。临床医生在纠正电解质失衡时应保持警惕，尤其是伴有合并症时。
一名41岁女性在度假期间出现类似急性帕金森综合征的特征。这是在反复呕吐后低钠血症缓慢纠正之后出现的。MRI改变提示脑桥外髓鞘溶解症（EPM）。该病例与医学文献中报道的先前4例病例不同，该患者实现了完全临床康复，且仅通过对症支持治疗，MRI改变就得以缓解。
仅通过对症支持治疗，脑桥外髓鞘溶解症即可实现完全康复。在纠正低钠血症期间，导致高钠血症的液体快速渗透变化会引起髓鞘溶解，而非绝对血清钠水平。即使是低钠血症的逐渐纠正也可能导致髓鞘溶解，尤其是在存在营养不良、酗酒、药物滥用、艾迪生病和免疫抑制的情况下。苍白球不受累是MRI扫描中EPM的典型表现。
