Predictive Role of Electroencephalography in Regard to Neurological and Cognitive Sequelae After Acute Central Nervous System Infection

Abstract

Introduction: Electroencephalography can also be used to monitor long-term recovery of the patient after acute phase of the disease. Impaired neurocognitive function after infection, similar to brain injury, may present a transient but also prolonged problem for the functioning of an individual. Some studies have shown that importance of EEG may not be significant in sequel monitoring, because the extensive changes in EEG seen with severe forms of CNS infection do not necessarily imply a longer-term poor outcome. Aim: To examine the predictive potential of electroencephalography (EEG) in regard to the emergence of neurological and cognitive sequelae of acute central nervous system (CNS) infection. Methods: The study included 62 patients treated at the Clinic for Infectious Diseases, Clinical Center of Sarajevo University, who were diagnosed with acute CNS infection. The EEG record was characterized as: normal, non-specific changes of mild, moderate and severe degree and specific changes. The sequelae (headache, cognitive dysfunction, neurological and neurophysiological disorders, audiological and behavioral disorders) was evaluated by combining neurological, psychiatric, pediatric, otolaryngological, ophthalmic and infectological examination in the Neuroinfective Counseling Department for up to 6 months after discharge. Results: After a treatment of an acute CNS infection 25 (40.3%) patients had no sequelae and 37 (59.7%) were with sequelae. The EEG in the initial stage of the disease (Wald’s coefficient = 12.8), followed by the age of the patients (Wald = 6.4), had the greatest influence on the prediction of sequela (p=0.0001). For each additional degree of verified pathological changes in the EEG, the risk of sequelae was increased by 5 degrees (OR = 5.3), respectively. There was no statistically significant association between changes in cerebrospinal fluid (CSF) findings, meningeal symptoms, and signs with sequelae development. Conclusion: Younger age, as well as severe clinical status of a patient, which implies a disorder of consciousness and seizures on admission, are associated with irreversible consequences on a previously mentally healthy individual. Pathological changes (Delta and Theta waves, spike slow complex wave) on the EEG finding significantly predicted presence of sequelae. .