ObjectiveDue to the similarities in the physiological mechanisms and antigenicity of the kidney and cochlea, they are simultaneously affected by certain diseases and drugs. Therefore, the purpose of this study was to investigate whether the hearing functions of patients with nephrotic syndrome (NS) were affected by the severity of the disease and the cyclosporine treatment. MethodsThe sample of this study consisted of 87 participants, including 65 patients (130 ears) with NS and 22 age- and sex-matched normal hearing children (44 ears). Based on the severity of the disease, the patients were divided into two groups: infrequently relapsing nephrotic syndrome (IRNS) and steroid-dependent or frequently relapsing nephrotic syndrome (SD/FRNS). Their audiologic tests, including Pure-tone Audiometry and Distortion-Product Otoacoustic Emission (DPOAE), were compared with the tests of the control group. In addition, the audiologic tests of the NS patients who received cyclosporine were compared with those who did not. ResultsIn the pure-tone audiometry, there were statistically significant differences between the IRNS, SD/FRNS, and control groups at 2000, 4000 Hz, and pure-tone average (PTA). Hearing levels of the SD/FRNS group at 2000, 4000 Hz, and PTA were higher than those of the control group. At 6000 Hz in pure-tone audiometry, there was a very weak positive correlation between the hearing level and the number of relapses. At 250 Hz and PTA, hearing levels of the group that received cyclosporine were higher compared to the group that did not receive it. In DPOAE, there was no significant difference between the groups according to the severity of the disease and the use of cyclosporine. ConclusionDuring the follow-up of the patients with NS, their hearing functions should be questioned, especially in patients with SD/FRNS and receiving cyclosporine treatment.