MRI Findings of Two Patients With Hashimoto Encephalopathy

Hashimoto encephalopathy (HE), also known as steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT), is a rare type of autoimmune encephalitis that typically presents with cognitive and neuropsychiatric symptoms that resolve with steroids. Positive neuroimaging findings of HE are rarely reported in the literature. We present two cases of HE with abnormal MRI findings, including signal abnormalities in the claustrum, cerebral white matter, and mesial temporal lobes. HE and other forms of autoimmune encephalopathies can often be misdiagnosed as viral encephalopathies. As such detection of subtle neuroimaging findings in the context of suspicious clinical history should prompt further investigations to ensure accurate and timely diagnosis.