Brainstem auditory-evoked potential evaluation in children with meningitis

Abstract

Brainstem auditory-evoked potential (BAEP) was performed on 101 children with meningitis to assess the incidence of hearing impairment. Fifty-two (51.5%) children had bacterial meningitis, six (5.9%) had viral meningitis, and 43 (42.6%) had aseptic meningitis. Fifty-one (50.5%) patients were assessed before discharge and 50 (49.5%) 9 days to 17 months later (mean = 4 months). BAEP impairment was found in 28 (27.7%) of 101 patients; 24 had sensorineural and four had conductive type of hearing loss, and 17 (60.7%) had unilateral and 11 (39.3%) had bilateral impairment. Hearing threshold was elevated in 22 (21.8%) patients, and the other six had increased latency and interpeak latencies with normal threshold. Frequency of BAEP impairment or hearing loss associated with bacterial meningitis was 34.6% and 30.8%, respectively; frequency associated with aseptic meningitis was 20.9% and 13.9%, respectively. One child with viral meningitis (coxsackie virus) had mild BAEP impairment. Most of the BAEP impairment in the bacterial meningitis group was associated with H. influenzae. Prospective BAEP study was performed in 20 patients randomly at 0.3 to 18 months to assess hearing status after antibiotic treatment, 10 with normal and 10 with abnormal BAEP. All the initially normal BAEP patients remained normal. Of the 10 patients with abnormal BAEP results initially, four returned to normal, two improved, three remained unchanged, and one deteriorated. The incidence of hearing loss after bacterial and aseptic meningitis is high. BAEP is useful to screen for possible hearing loss in children with meningitis, and follow-up BAEP is necessary for those patients with initially abnormal BAEP.