Proper Follow-up After Failed Hearing Screen in Newborns

A recent study, titled, “The loss to follow up of failed hearing screen and missed opportunities to detect congenital cytomegalovirus are better identified with the implementation of a new electronic health record system protocol” (June 2021 International Journal of Pediatric Otorhinolaryngology 148(4):110818 DOI:10.1016/j.ijporl.2021.110818), sought to identify areas for improvement in capturing children who failed their newborn hearing screen within 21 days in order to test for congenital cytomegalovirus (cCMV). The study focused on factors that prohibited follow-up hearing screening within three weeks and whether use of an electronic health record could help reveal those lost to follow up. We found the primary reason for loss to follow-up or delay in repeat audiologic testing was distance from their residence to the birth center where the initial newborn hearing screen was performed. We also found that lack of awareness of cCMV precluded any sense of urgency in identification of these babies. By implementing protocols to identify those babies who failed their newborn hearing screen and send cCMV testing prior to discharge, the rate of capture improved over time. Our current protocols allow for cCMV salivary testing after failure of the first screen to prevent the risk of discharge from the newborn nursery prior to obtaining follow up testing.

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CMV is a ubiquitous viral infection that is primarily asymptomatic when acquired after birth. Pregnant mothers with small infants or children in day care are more susceptible to infection with CMV. The risk of vertical transmission to the developing fetus is highest in the first trimester and can convey the most harm to the fetus, including hearing loss, microcephaly, neurologic delays and ophthalmologic problems. ^1–3 Symptomatic cCMV is generally readily apparent at birth with these findings, along with petechiae, elevated liver enzymes, thrombocytopenia and a characteristic “blueberry muffin” type rash. Asymptomatic cCMV is much more insidious and may only show up as a failed newborn hearing screen in about 7-10% of cases. ^4–7

Many children with asymptomatic cCMV pass their initial hearing screen and can develop delayed onset, progressive, or fluctuating sensorineural hearing loss. Identifying these children is much more difficult and requires diligence in follow--up. cCMV needs to be identified within three weeks before the baby has a potential for contracting acquired CMV, which does not carry the same long-term sequelae. Identification is done initially with a salivary or urine PCR test followed by a confirmatory culture if the PCR is positive. ^8,9 Treatment is then individualized based on recommendations from the pediatric infectious disease team.

Newborn hearing screening is performed during the first 24 hours after birth using an automated ABR. If the result is “refer,” the test is repeated within the next 12-24 hours. An additional “refer” then prompts an audiologic follow-up. This entails a non-sedated (natural sleep) ABR diagnostic test, otoacoustic emission testing, and tympanometry. This test is scheduled after the patient is discharged from the nursery and attempts are made to perform this diagnostic test within three weeks of birth. ¹⁰

Early identification of hearing loss is one of the primary objectives of the Joint Committee on Infant Hearing. Their most recent 2019 recommendations include identification of hearing loss within one month, diagnostic confirmation within two months, and habilitation within three months to prevent communication and educational delays. ¹¹

Our study examined trend over time regarding follow-up after initial failed newborn hearing screen in term infants, rate of CMV testing in those who failed their hearing screen, and length of time to outpatient follow-up. We identified 444 term infants who failed their first and second inpatient hearing screens from 2013-2016; 54 of them were found to have permanent hearing loss. Another 60 children were lost to follow--up with no audiological data available after their hospital discharge. Only two were identified with cCMV and both of them had profound SNHL leading to cochlear implantation. This accounted for a 0.4% CMV positive rate amongst those who failed their newborn hearing screen, although only 38 of the 444 were tested for cCMV overall.

We evaluated demographic and geographic data with the primary driver of lost to follow-up being the distance of residence from the birth hospital where the hearing screen took place. Providing contact information for audiology centers near the patient’s place of residence, education of the parents and primary care provider on the importance of close follow up, as well as timeliness of cCMV testing, are things that can be done to improve both identification and longer-term outcomes for these children. Increasing public awareness of CMV, its sequalae, and steps for infection prevention can make a big difference in identification and advocacy for early testing, along with close audiologic monitoring in cCMV positive cases.