Herpes Simplex Encephalitis with an Extensive Cerebral Lesion.

A 63-year-old man began acting abnormally 2 days after development of a fever. He was admitted to a nearby hospital where a brain CT scan showed no abnormality. After experiencing a clonic convulsion the day following admission, he fell into a coma. Five days after admission, CT scans revealed low-density areas in the left temporal lobe, and acyclovir was administered based on a tentative diagnosis of herpes simplex encephalitis. Twelve days after admission, the patient was transferred to the Emergency Department of Kawasaki Medical School Hospital. MR imaging revealed bilateral expansion of the lesions, and his EEG showed periodic lateralized epileptform discharges (PLEDs) on both sides. HSV-DNA in his spinal fluid was positive as determined by PCR examination. Acyclovir 1, 500mg/day was continued for 3 weeks, and the patient's consciousness improved slightly. Although lesions improved, as indicated by MRI, SPECT showed high uptake on the left side at least up to 71 days after fever onset. The patient survived with apallic syndrome. Although pharmacological intervention improved the prognosis of this disease, treatment must be initiated promptly.