Audiologic and vestibular assessment in children and adolescents with transfusion dependent beta thalassemia major: The era of deferasirox film coated tablet.

BACKGROUND: Hearing impairment has frequently been described in ß-thalassemia patients with a significant impact on the patients' quality of life. Most studies provided evidence of deferoxamine (DFO) dose-related ototoxicity, however, the data is scarce regarding deferasirox (DFX) as a sole iron chelator. AIM: We aimed to assess the prevalence and risk factors of sensorineural hearing loss (SNHL) and vestibular dysfunction in regularly transfused ß-thalassemia patients who had been treated with DFX film coated tablets. METHODS: We conducted a case control study on 57 transfusion dependent ß-thalassemia patients with a mean age of 15.3 years who received DFX FCT as monotherapy for at least one consecutive year, and 57 healthy age and sex-matching controls. Comprehensive audiological evaluations using pure tone audiometry (PTA) and transient evoked otoacoustic emission (TEOAE) as well as vestibular evaluation using Video-nystagmography (VNG) were done. RESULTS: SNHL was identified in 12 patients (21.1 %) using PTA and a statistically significant difference was detected between controls and patients at 6 KHz and 12 KHz frequencies. A higher incidence of SNHL was detected using TEOAE, 22 patients (43.1 %) failed to pass TEOAE, with a statistically significant decrease in the signal at frequencies 1, 4 KHz bilaterally and at frequencies 1.5, 2 KHz in the right ear compared to controls. Canal paresis was detected in 21 (36.8 %) of thalassemic children using bithermal caloric test with significantly more unilateral weakness than control children (P = 0.008). We found no significant correlation between audio-vestibular dysfunction and age, sex, serum ferritin, frequency of blood transfusion and dose of DFX FCT in thalassemic children. CONCLUSION: We conclude that the incidence of SNHL and vestibular dysfunction was high among transfusion dependent ß-thalassemia patients. Therefore, we recommend performing pre-treatment baseline audio-vestibular assessment and yearly audio-vestibular monitoring to early detect high risk patients and initiate timely management to prevent permanent damage.

Auditory cortical processing in cochlear-implanted children with different language outcomes.

PURPOSE: Behavioral evaluation of language development is an important index for the usefulness of cochlear implantation. However, it could not apply to infants and very young children. It is useful to adopt an objective measure to examine speech discrimination in this population. Thus, the current study aimed to predict the different behavioral language performance (good versus poor) in cochlear implant (CI) recipients through the auditory cortical assessment of speech discrimination with mismatch negativity (MMN). METHODS: The study comprised 40 CI children who were divided into two groups according to their behavioral language evaluation outcomes: 20 good and 20 poor CI performers. They were age, gender, and socioeconomically matched. The MMN was examined and compared between both groups with finding out the relationship between MMN and different variables. RESULTS: MMN existed in all good performers and 87.5% of the poor performers. There were significantly shorter latency, larger amplitude, and a larger area of MMN in the good performers. The MMN results correlated with a significant predictive effect on the behavioral measures of language evaluation. CONCLUSION: The MMN is a clinically applicable objective measure of speech discrimination proficiency. Hence, it could be useful in CI programming and auditory cortical monitoring during rehabilitation.