Impact of congenital cytomegalovirus infection on vestibular dysfunction and hearing outcomes in a cohort of children

This study aims to evaluate long-term vestibular function and hearing outcomes in a cohort of children with congenital cytomegalovirus infection (cCMV) using a comprehensive battery of vestibular and hearing tests, and possible relationships between vestibular and cochlear damage and relevant clinical presentation variables of cytomegalovirus (CMV) infection. A prospective cohort study was carried out from June 2016 to December 2023 and included 40 children affected by cCMV. Our sample was composed by 35% males and 65% females, with age at first vestibular assessment ranging from 3 to 8 years old, and 30% (12) were symptomatic at birth. All patients received their diagnosis during the neonatal period, with none diagnosed retrospectively through dried blood spots. The median follow-up period was 5.3 years (ranging from 4.6 to 6.0). Comparing children with and without symptoms related to CMV, the presence of hearing loss (50% vs. 0.0%, p = 0.0002), psychomotor delay (25% vs. 0.0%, p = 0.024) and vestibular dysfunction (VD) (66.7% vs. 17.9%, p = 0.0075) were significantly increased in symptomatic patients. The VD was confirmed with a reduced gain of the lateral semicircular canals (LSCC) at the video head impulse test (vHIT) (58.3% vs. 17.9%, p = 0.021), and with the absence of response at cervical vestibular evoked myogenic potentials (cVEMPs) (54.5% vs. 3.7%, p = 0.0009). Comparing children with and without VD, we found a significant presence of reduced LSCC gain during the vHIT (93.3% vs. 0.0%, p < 0.0001), of an exclusive alteration in cVEMPs (61.5% vs. 0.0%, p < 0.0001), of hearing loss (46.2% vs. 0.0%, p = 0.0004), of patients with symptoms related to cCMV at birth (61.5% vs. 14.8%, p = 0.0075), of pathological neuroimaging at onset (61.5% vs. 7.4%, p = 0.0006), presence of antiviral therapy (61.5% vs. 11.1%, p = 0.0017) and positive viremia at onset (100% vs. 63%, p = 0.018). Finally, about time of maternal CMV infection the first trimester was associated to children with VD, while the third trimester to children without VD. cCMV infection can involve the entire inner ear: vestibular function seems to be more affected than cochlear function. Therefore, vestibular evaluation should be included in the audiological work up and follow-up in children with cCMV.