Congenital cytomegalovirus infection is the most common cause of nonhereditary sensorineural hearing loss during childhood, according to researchers from Belgium.
Julie Goderis, MD, of University Hospital Ghent in Belgium, and colleagues conducted a systematic review of relevant articles on congenital cytomegalovirus (CMV) and hearing published within the last 50 years. Thirty-seven studies were included in the analysis.
Results indicated an overall prevalence of congenital CMV of 0.58% in developed countries.
Approximately 90.2% of children with CMV were asymptomatic and 9.8% were symptomatic. Nearly 33% of children with symptomatic CMV had hearing loss compared with 9.9% of asymptomatic children.
Overall, an average 0.5 per 1,000 children experienced hearing loss due to congenital CMV infection.
Among symptomatic children with congenital CMV, 71.2% had bilateral hearing loss and 28.8% had unilateral hearing loss. Over half of bilateral hearing loss was severe to profound (65.1%) and warranted hearing amplification and rehabilitation. Delayed onset of hearing loss occurred among 18.1% of symptomatic children. An estimated one in six symptomatic children with hearing loss experienced progressive loss, and one in five had fluctuations in hearing loss.
Among asymptomatic children, 57% had unilateral hearing loss. The majority of hearing loss among these children was severe to profound, though the percentage of asymptomatic children with bilateral hearing loss that was severe to profound was less than that of symptomatic children. Approximately 42.6% of asymptomatic children with hearing loss required amplification and rehabilitation. Nine percent of asymptomatic children with hearing loss had delayed onset. One in five asymptomatic children with hearing loss had progressive loss, and one in four experienced fluctuations in hearing loss.
Researchers analyzed three additional studies to evaluate the relationship between maternal seroimmunity and hearing status in relation to primary or non-primary infection. Hearing loss occurred in 12.1% of primary infections and 11.8% of non-primary infections.
“This systematic review confirms the important role of congenital CMV in childhood sensorineural hearing loss. However, because of the lack of systematic screening for congenital CMV in newborns and the characteristics of the disease, underestimation of its role in hearing loss is likely,” the researchers wrote. “Until a CMV vaccine becomes available, behavioral and educational interventions are the most effective strategy to prevent maternal CMV infection.”
Disclosure: The researchers report no relevant financial disclosures.