EEG changes in tuberculous meningitis: a clinicoradiological correlation

Abstract

Objectives: The present study is aimed at describing electroencephalographic (EEG) changes in the tubercular meningitis (TBM) and correlating these with clinical and radiological findings.

Methods: All the patients underwent a detailed neurological evaluation, CSF analysis, EEG and CT scan studies. Outcome was assessed by the Barthel index (BI) score at the end of 3 months, into good (BI≥12) and poor (BI<12). Thirty-two patients with TBM have been included of which 3 were definite and the remaining highly probable. Their mean age was 28 (range 8–62) years and 8 of whom were females. The majority of these patients were in stage III.

Results: Clinical signs of raised intracranial tension were present in 9 and history of seizure in 11 patients. Cranial CT scan was abnormal in 22 patients. The CT scan abnormalities included hydrocephalus in 20, infarction in 11, exudates in 7 and tuberculoma in 4 patients. The EEG was abnormal in 24 patients. The EEG abnormalities included diffuse theta to delta slowing in 22 patients, intermittent rhythmic delta activity in frontal region in 15, right to left asymmetry in 5 and epileptiform discharges in 4 patients. At the end of 3 months, 5 patients died, 13 had poor, 3 partial and 11 complete recovery. The EEG findings correlated with the severity of meningitis, the degree of coma and outcome at 3 months as assessed by Barthel index score.