Fig. 1

A Coronal brain MRI T1-weighted images with gadolinium contrast on April 13 (Day 0) demonstrate leptomeningeal enhancement (arrows). These findings were transient and were not demonstrated on an MRI scan on April 19 (Day 7). Usually, leptomeningeal enhancement is suggestive of infection, vasculitis or neurosarcoidosis; however, the results of a comprehensive screening for these conditions were normal. It was particularly important to exclude herpes CNS infection (HSV 1, HSV 2, HHV 6,7) because these infections can precede or coexist with AE [4]. B Coronal brain MRI T2-weighted FLAIR images on April 19 (Day 7) demonstrate bilateral hyperintensities in the medial temporal region (arrows), suggesting limbic encephalitis