Operculum syndrome: unusual feature of herpes simplex encephalitis.

Herpes simplex encephalitis in adults and young patients carries a high mortality and morbidity. Its presentation may be nonspecific, sometimes hampering early diagnosis. Two young children are reported with herpes simplex encephalitis in whom the operculum syndrome was an outstanding feature. This syndrome is caused by focal, bilateral cortical damage to the anterior opercular regions resulting in anarthria and impairment of mastication and swallowing. After initiation of treatment with acyclovir in the early stage of the disease, the outcomes in both patients were characterized by good general recovery with persistence of deficits of speech, mastication, and swallowing, more pronounced in the patient who was comatose during the illness. Early recognition of the operculum syndrome as a presenting feature of herpes simplex encephalitis may expedite the diagnosis and thereby improve the prognosis.