MRI of the brain mimicking autoimmune encephalitis in Sjögren syndrome with chorea: a case report

Neurologic manifestations in primary Sjögren syndrome (SS) range in prevalence from 8 to 49%, and most of the studies suggest a prevalence of 20%. The incidence of SS patients developing movement disorders is about 2%.

The authors herein report a case of a 40-year-old lady with MRI of the brain mimicking autoimmune encephalitis in SS who presented with chorea. Her MRI findings revealed T2 and FLAIR (fluid-attenuated inversion recovery) high signal intensity areas in bilateral middle cerebellar peduncles, dorsal pons, dorsal midbrain, hypothalami, and medial temporal lobes.

There is still no evidence to support the definite use of MRI in characterizing the central nervous system involvement in primary SS, especially due to overlapping findings with age and cerebrovascular disease. Multiple areas of increased signal intensity in periventricular and subcortical white matter in FLAIR and T2-weighted image is commonly seen in primary SS patients.

It is crucial to consider autoimmune diseases like SS as a cause of chorea in adults, even in those whose imaging findings are suggestive of autoimmune encephalitis.