Congenital CMV Screening in Infants with Failed Newborn Hearing Screens

Background: Congenital CMV (cCMV) infection is a leading cause of non-genetic sensorineural hearing loss (SNHL). Although cCMV infection can lead to a range of manifestations, including microcephaly and neurodevelopmental delay, SNHL may be the only initial finding in 15% of infants with cCMV. Diagnosing cCMV requires detecting the virus during the first 21 days of life, and can be hampered by lack of clinician awareness and absence of routine patient follow-up within the testing window. A cCMV diagnosis provides families with information regarding prognosis, need for additional neurodevelopmental screening, and can eliminate the need for future unnecessary testing for genetic causes of SNHL. Local Problem: Targeted screening programs of cCMV infection in infants who fail their newborn hearing screen have been legislated in several states. Prior to initiation of this project, our institution did not routinely test for cCMV as a cause of congenitally acquired hearing loss. This misses a window of diagnosis and opportunities for early intervention. Interventions: An institution-wide guideline was implemented for screening. All infants who fail second newborn hearing screens with Audiology, and who are less than 21 days old, are eligible for cCMV testing. After a failed hearing newborn screen in Audiology clinic, parents are provided educational material about cCMV and information inviting them to the Pediatrics Clinic, where a non-sterile urine specimen is obtained for CMV PCR testing. The Pediatric Infectious Disease clinic will see all patients with a positive result. Results: Following initiation of the protocol, 17 out of 263 infants screened by Audiology over 10 months failed their second newborn hearing screen. Of these, 12 were less than 21 days of life and thus eligible for cCMV screening. Of the 12 infants who were eligible for cCMV screening, 6 infants completed testing and all were negative. Interim analysis suggested that delayed evaluation after 21 days of life occurred due the fact that the number of infants needing hearing evaluation exceeded Audiology capacity. Interventions were made to improve the specificity of initial hearing screens on the newborn nursery, resulting in fewer infant referrals for hearing loss (Figure 1). Conclusions: Targeted screening for cCMV in infants who failed their second newborn hearing screen achieved a 50% test rate of eligible infants, compared to 0 tests prior to implementation. After investigating the poor rate of follow-through with testing, additional measures were taken to ensure capture of patients for testing by arranging an acute nursing appointment with the patient if needed following audiology testing to facilitate obtaining a urine sample. The results of these additional interventions are pending.