AUDITORY PATTERN IN DEAFNESS FOLLOWING MENINGOCOCCAL MENINGITIS
N.N. Mathur
Lady Hardinge Medical College, New Delhi, India
Forty four cases complaining of hearing loss following the attack of meningococcal meningitis most of them during its epidemic in Delhi between March 1985 and July 1985 and others as sporadic cases reported later were taken up for the audiological and clinical study. The different audiological tests including pure tone audiometry and the Auditory brainstem response were done at regular intervals for 21/2 years in such 88 ears of 44 cases. Most of the cases were in the age group 8-12 years with the youngest at 4 and eldest at 25 years. The initial hearing loss in these 88 ears was mild in l8, moderate in 18, severe in 28 and profound in 24 ears. However during the follow- up of 21/2 years 8 patients recovered completely, and 14 cases became worse. Most of the cases had the auditory involvement between 24-48 hours of illness and the audiological tests were performed as soon as it was possible to undertake them.
The severity of Sensorineural hearing loss (SNHL) following meningococcal meningitis may vary from mild to profound and in most of the cases it is bilateral and irreversible. It may be both cochlear and retrocochlear Factors influencing the auditory outcome in such cases include age of the patients and the severity of initial hearing loss. Younger patients usually have severe hearing loss and their auditory outcome is worse. Most of the patients have the auditory involvement during the peak of the meningeal inflammation ie. between 24-48 hours of onset of illness. Evidence of SNHL in the patients of meningococcal meningitis suggests that the hearing evaluation must be done in all these cases both during and after the disease.