Introduction: The cochlear cells in kidney and inner ear have similar anatomic, physiologic, immunologic and pathologic properties in microscopic view. Renal glomerule is similar to stria vascularis as compared with the tubules. For this reason nephrotoxic drugs, electrolyte imbalances, biochemical, immunological, osmotic and vascular differences may influence on middle- inner ear and central pathway. Here, we aimed to evaluate the middle ear mechanism, outer hairy cell function in inner ear and hearing threshold in renal transplant (RT) patients.
Methods: From November 1975 to December 2019, we performed 3071 renal transplant procedures in Başkent University. In this prospective study; 30 RT recipients (60 ears; study group) and 30 healthy volunteers (60 ears; control group) were included. All patients underwent audiologic assessment by means of pure-tone audiometry, otoacoustic emission (OAEs) and contralateral suppression TEOAEs (CS-TEOAEs) measurements.
Results: Mean follow-up time after RT was 6.8 ± 6.1years (1-20 years). Hearing performance for the four frequency averages between groups was significantly different (p=0.002). When the cochlea outer hairy cells were evaluated, the signal-to-noise ratio was significantly lower at frequencies of 1000 and 1400 Hz between the patient and the control group (p=0.000, p=0.008). When the frequency-specific suppressions were assessed, there was no significantly lower suppression in all frequency in the RT group, but significantly lower suppression was found in all frequencies (for all frequency, p=0000).
Conclusion: Our results support the presence of auditory dysfunction in RT recipients. Low levels of OAEs support that RT recipients are prone to cochlear dysfunction. Therefore, audiometric evaluation of patients should be done before and after RT.