Aetiology of profound bilateral sensorineural hearing loss in children: clinical spectrum in North-Eastern Nigeria

Abstract

Background: profound bilateral sensorineural hearing loss has being a major hearing disability in children worldwide, most especially in tropical sub-Saharan Africa. Various aetiological factors ranging from congenital causes, maternal and childhood infections to the use of ototoxic drugs have been implicated. This study aims at highlighting the various aetiological factors and the pattern of profound bilateral sensorineural hearing loss in children.
Methodology: Case files of two thousand, seven hundred and sixty-one children aged 1-15yrs who presented to our facilities during the study period, with all types and grades of hearing loss were reviewed. Out of this four hundred and thirty-six (436) were children that presented with profound bilateral sensorineural hearing loss; the obtained data was documented on a structured pro forma questionnaire for statistical analysis. The variables include the socio-demographic data of the children, the various aetiological factors of hearing loss at presentation, laboratory investigations; and detailed clinical and audiological assessment.
Results: Among the 2761 case files of children with both conductive and sensorineural hearing loss that was retrieved, 436(15.8%) with profound bilateral sensorineural hearing loss was analyzed. There were 264 males and 172 females, with M: F =3:2, age-group of 1-4yrs was found to be the most affected with 184.0(42.2%).Generally more males affected than females. There was a decrease in the frequency of profound sensorineural hearing loss with increasing age. Unknown (idiopathic) causes were found to be the commonest aetiological factor with 144.0 (33.0%), this was followed by measles and meningitis infections with 21.6%, and 14.4% respectively.
Conclusion: Profound bilateral sensorineural hearing loss still remains a major childhood disability in our environment. More efforts should be made towards providing facilities for effective virology and genetic studies in our health care institutions. Intensive immunization campaign, especially against measles and meningitis should be emphasized nationally.