Management of Prenatal Expanded Genetic Carrier Screening Results for Autosomal Recessive Sensorineural Hearing Loss.

Abstract

Objective: Expanded carrier screening (ECS) identified couples at-risk to have a baby with an autosomal recessive genetic condition. Several genes implicated in sensorineural hearing loss (SNHL) are included in prenatal or preconception genetics ECS testing. Early identification of SNHL risk may enable prognostication of hearing loss, early educational intervention, and minimization of unnecessary diagnostic testing. We sought to describe cases where ECS enabled early SNHL-risk identification.

Study design: Retrospective chart review.

Setting: Maternal-Fetal Care Center and Otolaryngology department at an academic tertiary hospital.

Methods: Medical records of parent-infant dyads with positive ECS results for variants in autosomal recessive SNHL genes were reviewed. Data regarding genetic diagnostic testing, newborn hearing screening, time to HL diagnosis, audiological evaluation, and clinical consultations were compiled.

Results: Fifteen pregnant with positive ECS results for SNHL were referred for consultation with a pediatric otolaryngologist and genetic counselor. Generally, these couples were highly educated and adequately insured. 14 had pathogenic variants for GJB2 and 1 for USH2A. Four couples pursued prenatal genetic diagnosis via amniocentesis; 11 couples deferred genetic testing to the postnatal period or waited for initial hearing evaluation. Six babies inherited biallelic GJB2 mutations. Four were found to have SNHL on ABR by age 5 weeks and received follow-up management, 1 had a normal hearing evaluation despite being gene-positive, and 1 was lost to follow-up before hearing evaluation.

Conclusions: Carrier screening and confirmatory prenatal or neonatal genetic testing provided considerable lead time for early audiometric testing and appropriate intervention services including hearing aid fitting.