BACKGROUND: Aminoglycoside-induced ototoxicity has been reported in neonates but 
its incidence is poorly defined, whereas vancomycin-induced ototoxicity has not 
been reported in neonates.
OBJECTIVE: To compare hearing test results in infants in a neonatal intensive 
care unit (NICU) who were or were not treated with extended interval gentamicin 
dosing and/or standard vancomycin dosing.
METHOD: A database of otoacoustic emissions (OAE), over a 5-year period of NICU 
admissions, was combined with databases of gentamicin and vancomycin dosing to 
compare patients treated or not treated with these antibiotics.
RESULTS: A total of 2,347 OAE results was available. OAE failure rates were: no 
gentamicin and no vancomycin (noGnoV), 7% (85/1,233); gentamicin but no 
vancomycin (GnoV), 4% (42/949); vancomycin but no gentamicin (VnoG), 22% (9/41) 
and gentamicin and vancomycin (GandV), 14% (17/124). Compared to noGnoV there 
was a decreased risk of OAE failure in GnoV (p = 0.022, OR 0.64, 95% CI 
0.44-0.94) and an increased risk in VnoG (p = 0.003, OR 3.46, 95% CI 1.54-7.75) 
and GandV, (p = 0.006, OR 2.20, 95% CI 1.26-3.83).
CONCLUSIONS: Gentamicin, as used and evaluated in this audit, showed no evidence 
of an increased risk of ototoxicity; what was observed was a statistically 
significant decrease in OAE failure rate. Vancomycin, by contrast, was 
associated with ototoxicity.