Meningo-encephalitis presenting as an acute paranoid psychosis.

A twenty-seven year old women with meningo-encephalitis and paranoid symptoms is presented. The patient was admitted to a psychiatric unit where, two months previously, her brother had been under treatment for a paranoid schizophrenic episode. The diagnostic lumbar puncture was performed after several days of increasing periods of disorientation, stupor, incontinence, posturing, and perseveration. There was no fever, no signs of meningeal irritation, and no localizing neurologic deficit. The problem of recognizing organic brain disease presenting as an acute psychotic episode is discussed. In this case, the positive family history was given inappropriate emphasis, while the good pre-morbid adjustment of the patient and the symptoms of confusion and headache were inadequately considered. Viral meningo-encephalitis, particularly that due to herpes simplex, often presents with a picture of behavioral abnormalities and minimal physical signs, and is easily confused with a functional process.