Silent Hearing Loss in Kidney Transplant Patients Receiving Tacrolimus: A Fact or a Myth?

Abstract

Background: It has been claimed that tacrolimus may have harmful effects on the auditory system, where it has been linked to ototoxicity and sensorineural hearing loss (SNHL). We evaluated silent SNHL in kidney transplant recipients (KTRs) receiving tacrolimus and the different factors affecting it compared to healthy controls. Materials and Methods: In this case control study, hearing functions were studied in 42 KTRs receiving tacrolimus as maintenance immunosuppressive therapy for more than 3 months in comparison to 27 age- and gender-matched healthy subjects using tympanometry, pure-tone audiometry (PTA), extended high frequency audiometry (EHFA), and transient evoked oto-acoustic emissions (TEOAEs). Also, different factors were studied in relation to SNHL. Results: PTA showed that 23.8%, 21.4%, and 4.8% had mild, moderate, and severe SNHL, respectively. One-fifth of KTRs had severe SNHL, according to EHFA. According to TEOAEs, 28.6% of KTRs had abnormal hearing. There was a significant positive correlation between the tacrolimus trough levels and the results of both the PTA (P = 0.002) and EHFA (P = 0.035) tests. Conclusion: SNHL was detected in about half of the studied KTRs. Silent SNHL in KTRs might be associated with higher tacrolimus trough levels.