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Abstract Hepatitis C virus (HCV) infection is a serious global health problem that affects about 300 million people worldwide. It is estimated that three to four million people are infected every year. The backbone of HCV treatment is pegylated interferon-alfa and ribavirin (RBV) combined therapy. In general, treatment duration of 48 weeks is recommended. HCV RNA measurements at week 4, 12 and 24 are important for a response- guided treatment approach for PEG-IFN/RBV. If at these time points, the viral load threshold is exceeded or detected in serum, therapy should be stopped. Although the systemic side effects have of HCV combined therapy have been well-documented, little is known about its effect on the hearing system. One of the proposed side effects of therapy was ototoxicity. This study aimed to study the effect of combined pegylated interferon and ribavirin (PEG-INF/RBV) therapy on the hearing profile of hepatitis C (HCV) patients. The proposed ototoxic effect was studied through a test battery approach which entailed history taking, otoscopic examination, immittancemetry, speech audiometry, pure tone audiometry (PTA) including testing frequencies in the conventional range (250, 500, 1000, 2000, 3000, 4000, 6000 & 8000 Hz) and in the extended high frequency range (9000, 10000, 11200 & 12500 Hz), and distortion product otoacoustic emissions (DPOAEs) in the form of a DP gram. Patients were tested immediately prior to the commencement of therapy, at the end of the 12th week of therapy and at the end of the 24th week of therapy. This study was carried out on 74 chronic hepatitis C patients assigned to combined therapy (PEG-INF+RBV). Of those 74 patients 45 (60.8%) were males and 29 (39.2%) were females. Patients ranged from 20- 59 years of age; with the greatest bulk (60.7%) appearing to be in the age group of >40 – 59 years. Detailed history of otologic complaints was taken throughout the study. Prior to the commencement of therapy, neither of our patients complained of hearing loss, tinnitus, vertigo nor otalgia; thus fulfilling the selection criteria for our study. Throughout the 24 weeks of the study, otologic complaints were insignificant except for tinnitus; where a significant rise was observed from 0% to 31.1% by the end of the study. Audiometric results showed that of all tested frequencies, a statistically significant difference in hearing thresholds was identified for the frequencies 3000, 4000, 6000, 8000, 9000 and 10000 Hz in the time period 0-24 weeks of treatment; with an apparent critical time period of 12-24 weeks. Whereas, at higher frequencies (11200 and 12500 Hz), a statistically significant difference in hearing thresholds was observed in the time period 0-24 weeks of treatment; suggesting a critical time period of 0-12 weeks. |