Evaluation of Gentamicin Ototoxicity in Newborn Infants: A Retrospective Observational Study

Background The main purpose of this study was to demonstrate the effect of gentamicin on hearing tests in newborns treated with gentamicin in our NICU, and to contribute to the selection of antibiotics more consciously. Materials and Methods: Infants who were hospitalized and followed up in the NICU of Karabük University Medical Faculty Hospital, Karabük, Turkey, between December ۲۰۱۹ and November ۲۰۲۰ were included in our study. During the study period, ۳۳۱ infants hospitalized in the NICU and meeting the inclusion criteria were included.The infants were divided into two groups, with and without gentamicin treatment, and their demographic characteristics, respiratory support treatment and hearing test results were retrospectively analyzed and the results were compared. Automated auditory brainstem response (ABR) was used for newborn hearing screening at discharge. Results: Demographically, maternal age and birth weight were found to be significantly lower in gentamicin patients. Delivery method and gestational age were similar between the two groups. While the rates of passing the first test in the ABR screening were higher in the gentamicin group (p=۰.۰۵۱), only ۱ infant in the same group failed the ABR second screening. This infant was ۳۴ weeks old, a fraternal twin born at ۲۲۰۰ g, and no hearing loss was found in the infant’s twin. When the anamnesis was observed in detail, the infants’ uncle manifested a history of hospitalization for the treatment of urinary tract infection in his youth. In the meantime, his history of amikacin treatment and consequent experience of sensorineural hearing loss was revealed. Conclusion We concluded that gentamicin does not affect the hearing test when it is not used in the short-term (۵-۷ days), extended dosing intervals (۲۴-۴۸ hours), and ototoxic drugs such as loop diuretics.