This study was carried out to determine the characteristics and incidence of hearing loss and vestibular disturbance in Behcet's syndrome with a large number of patients. Sixty-two patients with Behcet's syndrome were included in this study, 34 men and 28 women whose mean age was 33.7 (15-60). Sixty-two healthy normal control subjects (38 male and 24 female) were included. Patient and control groups were questioned about any history of audio-vestibular disturbance and underwent physical and ENT examination and the following audiologic tests: pure tone audiometric test (0.25, 0.5, 1, 2, 4, and 6 kHz), tympanogram, speech discrimination, short increment sensitivity index, tone-decay test, auditory brainstem response. Vestibular system was evaluated by videonistagmogram and caloric test. Cranial and brainstem magnetic resonance imagine (MRI) of patients who have vestibular disturbances were practiced to examine the central nervous system. Both the patient and the control groups were tested with the HLA-B51 antigen. Pure tone audiogram showed sensory-neural hearing loss (25 dB hearing level in at least two frequencies) in 20 of the 62 (32%) Behcet's patients while the control group were normal. There was a hearing loss involving high frequencies in the audiograms of Behcet's patients with hearing disturbances. The recruitment investigation tests and auditory brain stem response confirmed cochlear involvement in all 20 patients. Caloric stimulation tests revealed a normal vestibular function in all patient and control group. In electronystagmography, 21 (34%) patients had hypometric or hypermetric saccades and smooth pursuit tests showing that 4 (6%) patients had pathological changes while the control group was normal. HLA-B51 antigen was found positive in 15 of 20 Behcet's patient with hearing loss.
Conclusion: (1) The hearing and vestibular disturbances in Behcet's syndrome is more prevalent than previously recognized; (2) Hearing loss in high frequencies in Behcet's patients is an indicator of cochlear involvement in this disease; (3) There is a higher prevalence of central vestibular syndrome in Behcet's patients than it was thought before; (4) HLA-B51 antigen may be able to be a prognostic factor for sensorineural hearing loss in Behcet's patients.