The CSF showed pleocytosis and high protein. Herpes simplex virus (HSV) infection was confirmed on PCR. The limbic system's clinical findings and predominant involvement in imaging are highly suggestive of herpes simplex encephalitis. The patient was commenced on anti-virals but subsequently succumbed to the infection.

Differential includes an MCA territory infarct; however, sparing the basal ganglia helps distinguish it from herpes encephalitis. Autoimmune encephalitis is a consideration within the correct clinical scenario of underlying malignancy.