Background: Hyperbilirubinaemia is a contributing condition to the prevalence of neonatal hearing loss. Because of its pathophysiology, the use of Otoacoustic Emissions (OAE) and Automated Auditory Brainstem Response (AABR) testing is essential in diagnosing hearing loss. Two-tier screening models are typically used in developing world contexts; however, a combined approach to testing (using both tests) should be used for early detection. Blood serum levels should also be monitored to determine how they impact audiological test results.
Objectives: To determine the outcomes of using a combined testing approach of both OAE and Auditory Brainstem Response (ABR) for both screening and diagnostic testing of neonates with hyperbilirubinaemia and studying the relationship between the test results and the serum bilirubin levels.
Method: A cross-sectional, comparative design was utilised. Forty neonates were tested (80 ears). Neonates underwent hearing screening and diagnostic testing (ABR and/or AABR and DPOAE tests). The study was conducted at a hospital in South Africa.
Results: One-third (32.5%) of the neonates had comorbidities. Screening results indicated that the AABR test could identify more cases of abnormalities than DPOAEs (p = 0.001). Participants with a serum level greater than 10 mg/dL presented with abnormal diagnostic ABR test results while passing the DPOAE test (p 0.001).
Conclusion: Combined use of ABR and DPOAE testing yielded a greater identification of auditory pathology than using either test alone. Serum bilirubin levels can be used as an indicator for combination testing.Contribution: Combined use of ABR and DPOAE testing leads to greater identification of auditory pathology.
Keywords: auditory brainstem response; hearing loss; hyperbilirubinaemia; low birth weight; neonates; otoacoustic emissions; serum bilirubin level..