The electroencephalogram in adult patients with fever.

In order to determine if adult patients have reversible EEG abnormalities concurrent with fever, EEGs were recorded during fever in patients without neurologic disease or systemic disease capable of involving the central nervous system, and these were compared blindly with EEGs from the same patients taken at least 30 days after the febrile illness had disappeared. Fourteen patients completed the study, 10 men and 4 women, between the ages of 24 and 56 years, with fever secondary to localized infection. The global frequency of abnormal EEGs was high compared with the general population, since only 6 patients had both records completely normal; in 4 of these 6 cases during fever there were sleep patterns, mainly the first phase of slow wave sleep. Patients with localized abnormalities during fever showed the same abnormality in the EEG taken without fever, with two exceptions, one in which the abnormal finding disappeared and one in which another abnormality replaced the first one. Two patients had normal EEGs during fever and paroxysmal theta waves with predominance in their EEGs taken one month later. Fever in adults seems not to provoke rapidly reversible EEG changes. The high proportion of abnormal EEGs in these patients, and the appearance of new abnormalities in two cases after fever, deserves further research concerning the long-term effects of febrile illness on the EEG in adult patients.