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Updated: Sep 10, 2026
Neuro-rehabilitation Approach for Sudden Sensorineural Hearing Loss
Published on: January 25, 2016
A wider role for congenital cytomegalovirus infection in sensorineural hearing loss
Maria Barbi1, Sandro Binda, Simona Caroppo
1Insituto di Virologia, Università di Milano, Milan, Italy. maria.barbi@unimi.it
Insights
Congenital cytomegalovirus (CMV) infection is a significant cause of sensorineural hearing loss (SNHL) in infants. This study found CMV DNA in 10% of infants with early-diagnosed SNHL and 34.2% of children with later-diagnosed, unexplained deafness.
Area of Science:
- Pediatrics
- Infectious Diseases
- Audiology
Background:
- Identifying congenital cytomegalovirus (CMV) infection in infants is challenging, hindering understanding of its role in sensorineural hearing loss (SNHL).
- Previous assessments of CMV's impact on SNHL etiology have been limited by diagnostic difficulties.
Purpose of the Study:
- To estimate the prevalence of congenital CMV infection in children diagnosed with SNHL.
- To utilize stored neonatal dried blood spots for CMV DNA detection to assess its contribution to SNHL.
Main Methods:
- Retrieved Guthrie cards from 130 children with SNHL (>40 dB hearing loss).
- Extracted CMV DNA using thermal shock and amplified it via PCR.
Main Results:
- Congenital CMV infection accounted for 10% of SNHL cases diagnosed within the first two months of life.
- In children with unexplained deafness diagnosed later, CMV DNA was detected in 34.2% of cases.
- Among children with severe SNHL (>70 dB) of unknown cause, 42.7% tested positive for CMV.
Conclusions:
- Congenital CMV infection plays a more substantial role in SNHL etiology than previously recognized.
- CMV infection may be responsible for 20-30% of all childhood deafness cases.
- Congenital CMV infection alone accounts for a significant portion of deafness previously attributed to various congenital infections, particularly in cases with unknown etiology.
Background:
Diagnostic problems in identifying congenital infection cases in infancy have thus far impaired the assessment of the role of congenital cytomegalovirus (CMV) infection in the etiology of sensorineural hearing loss (SNHL).
Objective:
To estimate the impact of congenital infection in children with SNHL by detection of CMV DNA in stored samples of neonatal dried blood (dried blood spots test).
Methods:
The Guthrie cards of 130 children with hearing loss >40 dB hearing loss were retrieved from the regional screening center. CMV DNA was extracted by thermal shock and amplified by PCR.
Results:
The percentage of SNHL cases attributable to congenital CMV infection was 10% (9 of 87) in infants whose SNHL had been diagnosed in their first 2 months of life and 34.2% (13 of 38) in children with deafness of unidentified cause that was diagnosed in early childhood. In the latter group 42.7% (12 of 28) of the children with a hearing loss of >70 dB were CMV-positive.
Conclusions:
The results suggest that congenital CMV infection has a more relevant role in the etiology of SNHL than previously reported. The data obtained in both groups suggest that 20 to 30% of all deafness cases are caused by CMV. The percent of congenital CMV cases alone appears to account for all the cases previously attributed to all congenital infections. More than 40% of deafness cases with an unknown cause, needing rehabilitation, are caused by congenital CMV.
