Detection of sensorineural hearing loss using automated auditory brainstem-evoked response and transient-evoked otoacoustic emission in term neonates with severe hyperbilirubinaemia.

INTRODUCTION

This study was designed to compare the sensitivity and specificity of detecting sensorineural hearing loss (SNHL) using the transient-evoked otoacoustic emissions (OAE) machine (the Madsen TE Echoscreen) and automated auditory brainstem response (AABR) machine (the Sabre Compac portable AABR) in term neonates exposed to severe hyperbilirubinaemia.

METHODS

This was a prospective study carried out over a 30-month period in a neonatal intensive care unit. Term infants (gestation equal to or greater than 37 weeks) with severe hyperbilirubinaemia (peak total serum bilirubin level equal to or greater than 300 umol/L) were recruited. Hearing tests were carried out before discharge.

RESULTS

The median age of the 250 study infants when OAE and AABR were tested, was eight days (IQR four days) and their median age when auditory brainstem-evoked response (ABR) was done was 58 days (IQR 56 days). Based on the findings of ABR, 32 (12.8 percent) infants had unilateral or bilateral SNHL. There was no significant difference in the peak total serum bilirubin levels between infants with SNHL (median 333 umol/L, IQR 57) and those without (median 340 umol/L, IQR: 58) (p-value is 0.3). The sensitivity of OAE for detecting SNHL was 15.9 percent, and its specificity 95.2 percent. The sensitivity of the Sabre Compac portable AABR machine for detecting SNHL was 40.9 percent and its specificity was 63.2 percent.

CONCLUSION

Both the OAE machine and the Sabre AABR machine were not sensitive enough for mass screening of SNHL in infants exposed to severe hyperbilirubinaemia.