Early diagnosis and evolution of deafness in childhood bacterial meningitis: a study using brainstem auditory evoked potentials.

Fifty-one children with bacterial meningitis were studied prospectively using serial recordings of brainstem auditory evoked potential (BAEP) from the earliest phase of the disease, according to a standardized protocol. The objectives were to make an early diagnosis and follow the evolution of deafness in the course of meningitis and evaluate the prognostic value of BAEP. Thirty-five children (68.6%) always had normal recordings; 11 children (21.6%) had transient BAEP abnormalities (prolonged wave V latency or elevated threshold for wave I), and five children (9.8%) had persistent pathologic BAEP recordings from the first examination at 48 hours until discharge from the hospital and have a persistent deafness. All recordings that were normal or pathologic at discharge were confirmed by behavioral audiometry 3 months later. These results show the early occurrence of deafness in the course of meningitis with a crucial phase of possible recovery or worsening occurring during the first 2 weeks. There were no cases of "late" deafness or "late" recovery (there was sometimes slight improvement) occurring after discharge; thus BAEPs have a prognostic value. However, observation of a child with clinically proven selective high-frequency postmeningitic deficit but without a hearing handicap, a disorder that was diagnosed early with BAEP (which tests only the high frequencies), is a warning that this method alone is insufficient and that clinical auditory surveillance and conventional audiometry remain necessary.

[Importance of auditory "screening" in the school and preschool environment in relation to language disorders]. / Importance du "screening" auditif en milieu préscolaire et scolaire lors de troubles du langage.

Having recalled the acoustics spectrum of the human voice and different types of deafness, the author describes alarm signs of various hearing disorders. Bearing in mind the importance of early detection of deafness for optimal speech development, special emphasis is put on the necessity of mass hearing screening in kindergarten and nursing school. However, the diagnosis may be delayed in less severe deafness; medium hearing loss between 35 to 65 dB being scarcely detected before age 5! In this respect teacher's and school health professional's particular attention should bring the child to a specialised diagnostic and therapeutic center where medical or surgical audioprosthetic treatments could be performed before developmental retardation occurs. Two case records are presented.