HEARING IMPAIRMENT IN CHILDREN UNDER 16 M ONTHS AFTER BACTERIAL-MENINGITIS WITH REFERENCE TO ELASTASE IN CEREBROSPINAL-FLUID

Hearing impairment as a sequela of acute bacterial meningitis is a wel l known complication. Dexamethasone therapy in addition to antibiotics is beneficial in the reduction of deafness, implicating that inflamma tion may be one reason for hearing impairment. The risk of hearing imp airment in different types of bacterial meningitis is well studied. In very young children < 1.5 years of life the incidence of hearing loss and the possible correlation of laboratory data with the development of deafness is yet unknown. We therefore examined the brainstem audito ry evoked potentials in 25 children between the first month and the 16 th month of life who we treated for meningitis during 3 years in our h ospital. 11 children were treated with dexamethasone. In 9 children we found abnormal brainstem auditory evoked potentials, which we control led every 3 months. 7 children had transient conductive hearing impair ment with good recovery during the first year after the disease. In 2 cases we found permanent bilateral sensorineural hearing loss. There w as a significant relationship between hearing loss and elastase in cer ebrospinal fluid. Dexamethasone reduced this relationship. A screening of hearing should be performed as routine control in all patients wit h acute meningitis. The association of high elastase in cerebrospinal fluid and later hearing impairment indicates a pathophysiological rela tion between activation of granulocytes and hearing loss.