Evaluation of hearing loss and otolaryngeal disorders in beta thalassemic patients treated with desferrioxamine

Thalassemia is one of the most prevalent heamoglobinopathies in the world in particular in Iran. Major thalassemia patients need blood transfusion and desferrioxamin injections throughout their life. Regarding improved life quality of thalassemic patients, new clinical problems, such as hearing loss, need more attention. This study was done to determine the frequency of hearing loss and otolaryngeal disorders together with their related factors in major beta thalassemic patients. This was a descriptive analytic study and 84 beta thalassemia patients were examined and evaluated for hearing loss by an otolaryngologist. Standard pure tone audiometry was performed for the patients. Serum ferritin level was measured. Considering blood transfusion the patients were divided into two groups: those with suitable transfusions and those with unsuitable transfusions. Also in regard to desferrioxamin injections again the patients were divided into two groups: those with regular injections and those with irregular injections. Among 84 beta thalassemic patients (40 M, 44 F) with mean age of 12.8±5.7 years, 10 (11.9%) had sensorineural hearing loss, 8 (9.5%) had conductive hearing loss, while 8 (9.5%) showed mixed hearing loss. There was no relationship between hearing loss and age, sex, ferritin level, but hearing loss had a significant relationship with doses and duration of desferrioxamine therapy (P<0.01). Also hearing loss had no significant relationship with regular and irregular blood transfusions and desferrioxamine injections (P<0.01). The results of this study implicated that high dose desferrioxamine was the main factor in the pathogenesis of ototoxicity in thalassemic patients. For management of these patients it is necessary to use proper doses of desferoxamine. Also blood transfusions should be proportional to body iron burden and hemoglobin. In addition, regular periodic otolaryngologic and audiometric follow up examinations are required for early diagnosis of hearing disorders in prevention of permanent hearing loss.