There is a lot of hope that CI is the answer for single-sided deafness but, at this point, it is just hit or miss. There are no high-quality studies proving that it really works in this group of kids. —Judith E. C. Lieu, MD, MSPH
Explore This IssueJune 2019
Case 2: Congenital CMV and Hearing Loss
Case two is a newborn who has failed a hearing screening. Auditory brainstem response (ABR) is done in an expedited fashion per protocol before three weeks of age. The child is diagnosed with mild to moderate bilateral SNHL with a normal physical exam.
According to John H. Greinwald, Jr., MD, of the Ear and Hearing Center and professor in the departments of otolaryngology and pediatrics at the University of Cincinnati, the key in this case is to get an expedited cytomegalovirus (CMV) test. In Ohio, all newborns who fail their initial screening have ABR within two weeks. CMV is the most common non-genetic cause of hearing loss in children, he said, with roughly 10% to 15% of patients eventually developing hearing deficits.”
“A CMV microculture of a salivary swab/urine is also widely available and is highly sensitive and specific, said Dr. Greinwald. “The downsides are that it is slightly more time consuming and can have somewhat higher personnel costs.
“The CHIMES study indicates that if there is suspected congenital SNHL then you do early CMV screening and, if that is positive, then you give valganciclovir or ganciclovir for six weeks,” he added. “If those cannot be not tolerated, then consider a pressure equalizing tube and intratympanic antiviral therapy.”
Dr. Papsin said he disagreed on one point. “We screen for congenital CMV because it is important to identify this at birth. We have tried directed screening where we only do CMV testing on those who have failed a hearing screen, but we miss a lot of asymptomatic children who will go on to develop hearing loss. CMV is the new boogeyman of infant screening.”
Case 3: Child with Moderate-Severe Bilateral SNHL
Case three is a 5-year-old with moderate to severe bilateral SNHL who was treated with hearing aids for several years. His speech development is doing well, and there has been no evaluation for the etiology of the hearing loss.
Dr. Greinwald said, “In our practice we consider [that] all children from preschool to kindergarten who fail are likely congenital and that they are going to have similar causes of hearing loss. He said that more than half of hearing loss is genetic, with a lot of the literature showing that it is primarily non-syndromic. He cautioned that, while otolaryngologists should perform a physical exam, it is not always reliable, and he advised consulting with ophthalmology, genetics, and developmental pediatrics.
As for genetics, he said there is single gene testing (e.g., GJB2, 12SrRNA, SLC26A4) and multigene testing with Nexgen technology. There is also non-sydromic (recessive) and syndromic (Usher, SLC26A4, Alports, and Jervell and Lange-Nielsen). “With regard to genetics, our philosophy is that we are mostly looking for recessive causes of deafness,” he added. “You usually don’t need a genetic test to determine that someone has a dominant cause of deafness, since it is rare to find a new mutation. Many of these will look non-syndromic regardless of the child’s age. As for genetic counseling, there are not enough counselors available. If the child has craniofacial issues, then you should consult a medical geneticist.”
He also said that 20% of congenital SNHL cases will have inner ear malformations and, while imaging is important, it is expensive and insurance doesn’t typically cover it. “I argue that we image a newborn, not a 5-year-old, and that we do all MRIs at three months because, at that point, sedation is unnecessary,” he added.