[The prevalence and evolution of hypoacusis in Cooley's disease].

With the improved life expectation of patients with beta-thalassemia-major (BTM) or Cooley's Disease, new clinical problems, such as hearing damage, have emerged. The authors describe audiometric data of 50 patients with BTM. High-frequency thresholds were higher in BTM than those of a control group. Prevalence of hearing loss in BTM was 14-26%, depending on the frequency range considered, while in the control group it was between 4.3-19.1%. The prevalence of hearing loss in BTM with respect to that of the general population was 7-10% higher. Hearing loss ranged from mild to moderate. A good correlation was found between hearing loss and the cumulative dose of desferoxamine administered. These data were indicative of an ototoxic effect of this drug. Many patients (28.6%) showed significant hearing threshold deterioration after 3 years. On the light of these results, the authors suggest regular audiologic follow-up of patients with BTM.