Evaluation of hearing loss with auditory brainstem responses in the early and late period of bacterial meningitis in children.

The hearing function of 50 children with bacterial meningitis was evaluated at the second and 10th days, and eight weeks after admission with auditory brain system responses (ABR) to investigate whether meningitis causes hearing loss. Normal values were obtained in all tests from both ears of 24 patients (48 per cent). Twelve patients (24 per cent) had temporary, and seven (14 per cent) patients had persistent mild degree hearing loss. Severe hearing loss was detected bilaterally in five (10 per cent) patients and unilaterally in two (four per cent) patients. Patients, with other complications such as subdural effusion, convulsion, brain oedema and paralysis were found to have a higher incidence of hearing loss. We observed that patients treated with dexamethasone had 7.7 per cent persistent hearing loss, 11.6 per cent mild hearing loss, 34.6 per cent transient hearing loss, but in the group who did not receive dexamethasone there was 19.2 per cent persistent hearing loss, 15.3 per cent mild hearing loss and 11.6 per cent transient hearing loss. There were other significant differences between the two groups in restoration of normal body temperature, the CSF/plasma glucose concentration ratio was elevated, CSF (cerebro-spinal fluid) protein concentration was decreased and the cell count in the CSF was decreased in the dexamethasone group, significantly more than the group who were not receiving dexamethasone. The hearing loss tended to be more frequent among younger children.