A physical examination of a 29-year-old man with a headache and diarrhea revealed thyroid swelling. A neurological examination revealed that the deep tendon reflexes of the upper and lower limbs were increased, and postural tremors were observed. Brain magnetic resonance imaging showed a high signal in the splenial region (Picture A, B). After 29 days, the lesion had disappeared, and we classified it as clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) (Picture C, D). Tests were negative for viruses, tuberculosis, and legionella and were normal for vitamin and autoimmune diseases. The thyroid function was elevated, and a thyroid-stimulating hormone receptor antibody was positive. Therefore, we considered hyperthyroidism to have been the cause of MERS. Clinicians should consider hyperthyroidism as a potential cause of MERS, even though it is rare (1,2).
Picture.
Informed consent was obtained from the patient to publish his information.
Author's disclosure of potential Conflicts of Interest (COI).
Tsubasa Takizawa: Honoraria, Amgen, Daiichi Sanyo, Eli Lilly Japan and Otsuka.
Financial Support
The publication of this article was supported by a Keio University Global Research Institute (KGRI) Start-up grant for TT.
References
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