[Reversible posterior leukoencephalopathy syndrome in Hashimoto's encephalopathy: a case report].

A 45-year-old woman with breast cancer was admitted to our hospital because of several episodes of disturbed consciousness and generalized convulsions. While these symptoms resolved quickly, dysphagia and bilateral blepharoptosis persisted. Neurological findings were improved by steroid therapy. MRI on the first hospital day showed T2/FLAIR high intensity lesions in both occipital lobes, but these lesions diminished on the 8th day, indicating reversible posterior leukoencephalopathy syndrome. A new lesion appeared in the left temporal lobe on the 8th day. A diagnosis of Hashimoto's encephalopathy (HE) was made due to the following features: 1) encephalitis not due to herpes simplex virus, 2) high titers of antithyroid antibodies in serum, 3) marked effectiveness of steroid therapy, and 4) antibodies against the amino terminal of alpha-enolase, a specific antigen for HE.