الفهرس 
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Abstract
Vitiligo is an acquired depigmentary disorder that causes destruction of melanocytes in the skin, mucous membranes, uveal tract and retinal pigment epithelium of eyes and inner ear(Kemp and Waterman 2001).
The affection of extra-cutaneous melanocytes (auditory and ocular) in some vitiligo patients and the presence of other autoimmune disorders in association with vitiligo suggest that systemic immunological events directed against pigment cells might play a role in the development of the disease (Nordlund and Lerner 1992).
This study was designed to evaluate the effect of melanin deficiency in patients with vitiligo on cochlear and brainstem auditory function and to study the associated ocular and systemic abnormalities of vitiligo.
Subjects:
Study group included 40 vitiligo patients, their age range from 18-40 years and all the patients with a definitive diagnosis of vitiligo and control group included 20 normal subjects closely matched to the study group in age and sex.
Exclusion criteria for both study and control groups:
History of ototoxic drug intake, history of chronic noise exposure, history of head trauma and middle ear disorders.
Informed consent was obtained from all participants in the study and the study protocol was approved by Ethical Committee, faculty of Medicine, Assiut University.
Equipment:
Dual channel clinical audiometer (Madsen model Orbiter 922), double wall sound treated booth (″IAC″ model 1602-A-t), immittancemeter (impedance audiometer interacoustics model AZ 26), evoked response audiometer Nickolet Spirit version 2 and intelligent hearing system for TEOAEs.
Methods:
Detailed dermatological history and full dermatological examination of vitiligo patients, complete ocular examination, relevant lab investigations including CBC, liver and kidney function tests, random blood sugar level, autoimmune profile (ESR, RF, ASOT and ANA) and thyroid profile (T3, T4 and TSH) for vitiligo patients, otoscopic examination, basic audiological evaluation including (conventional PTA, speech audiometry and immittancemetry), high frequency PTA, TEOAEs and ABR.
Results:
The results of this study revealed that there were statistically significant elevation of hearing thresholds at frequencies 4, 8 and 10 KHz, no statistically significant differences in ABR parameters and statistically significant differences in TEOAEs S/N ratio values at all frequency bands tested and the overall responsesin the study group in comparison to control group.
Results of different audiological tests were not significantly related to the age of the patients, duration and severity of the disease, type of vitiligo and autoimmune profile.
Ophthalmic examination of vitiligo patients revealed that the ocular abnormalities (retinal or iris hypopigmentary disorders) were observed in 4 patients (10%).There were no statistically significant differences between the patients with and those without ocular abnormalities in all studied audiological tests (PTA, TEOAEs and ABR).
The disease duration and severity had statistically significant effect on the presence or absence of ocular abnormalities. However, the type of vitiligo and autoimmune profile had no statistically significant effect on the presence or absence of ocular abnormalities.