Pattern of Ototoxicity in a Nigerian Teaching Hospital

Abstract

Ototoxicity is a preventable cause of irreversible sensorineural hearing loss. This paper aims to highlight the pattern of ototoxicity seen in a tertiary health institution. A retrospective study of patients with ototoxicity seen over a seven year period at ENT department of Aminu Kano Teaching Hospital, Kano. Case notes were retrieved and studied. Fifty nine patients made up 37 males and 22 females were seen with 86% in the age group 20-60years. The commonest ototoxic drugs were aminoglycosides (37.3%), loop diuretics (27.1%), antimalarials (23.7%) and traditional concoctions (11.9%). The commonest presentation from most drugs was permanent sensorineural hearing loss (50-85%). Associated comorbid conditions included “febrile illness” (47.5%), hypertension (30.5%), diabetes mellitus (13.6%), renal disease (5%). Follow-up was poor. Only 18 patients presented for review beyond a second hospital visit, only those with ototoxicity from antimalarials recovered hearing. There were no effective audiometric and serum drug monitoring mechanism in place before, during or after therapy with ototoxic medications. Ototoxicity is not uncommon and attempts at prevention are feeble. Increased awareness of this condition is advised. High frequency audiometric assessment, otoacoustic emission and serum drug monitoring facilities should be provided at health institutions. Caution should be exercised when prescribing ototoxic drugs in the presence of other risk factors.

Key words: pattern, ototoxicity, hospital