Prevalence of hearing loss in patients with Beta thalassemia major, Hajar hospital of Shahrekord, 2002.

Thalassemia Major or cooley’s anemia is a hereditary anemia and its treatments have high incidence of complications in long term. One of these complications is hearing loss (conductive and sensory neural). Adenoid hypertrophy is the most important cause of conductive hearing loss and toxic effect of desferal is the most common cause of sensory neural hearing loss. The aim of this study was to find the prevalence of hearing loss in thalassemic patients referred to Hajar hospital of Shahrekord in 2002. This survey was performed on 78 patients with beta thalassemia major that regularly received transfusion therapy from about 6 months of age. For all of the patients audiometry were performed, serum ferritin level were measured, desferal dosage were asked and therapeutic index were calculated. Therapeutic index was lower than 0.025 at 89% of the patients, conductive hearing loss (CHL) was observed in 8 patients (10.3%) and sensory neural hearing loss (SNHL) was not seen. In patients with CHL, adenoid X-ray performed, and there was a significant correlation between CHL and adenoid hypertrophy (P<0.05). There was no correlation between hearing loss and age, serum ferritin level or desferal dosage. Absence of SNHL indicated good management of the patients. Appropriate control of thalassemic patients for level of serum ferritin and dosage of desferal and detection of therapeutic index can reduce sensory neural hearing loss. Also periodic control of these patients for hearing disorders can detect CHL and adenoid hypertrophy