Congenital cytomegalovirus (cCMV) infection is the most common nongenetic cause of sensorineural hearing loss in children. Due to the close anatomical relationship between the auditory and the vestibular sensory organs, cCMV can also be an important cause of vestibular loss. However, the prevalence and nature of cCMV-induced vestibular impairment is still underexplored. The aim of this study was to investigate the occurrence and characteristics of vestibular loss in a large group of cCMV-infected children, representative of the overall cCMV-population.
Ninety-three children (41 boys, 52 girls) with a confirmed diagnosis of cCMV were enrolled in this prospective longitudinal study. They were born at the Ghent University Hospital or referred from another hospital for multidisciplinary follow-up in the context of cCMV. The test protocol consisted of regular vestibular follow-up around the ages of 6 months, 1 year, 2 years, and 3 years with the video Head Impulse Test, the rotatory test, and the cervical Vestibular Evoked Myogenic Potential test.
On average, the 93 patients (52 asymptomatic, 41 symptomatic) were followed for 10.2 months (SD: 10.1 mo) and had 2.2 examinations (SD: 1.1). Seventeen (18%) patients had sensorineural hearing loss (7 unilateral, 10 bilateral). Vestibular loss was detected in 13 (14%) patients (7 unilateral, 6 bilateral). There was a significant association between the occurrence of hearing loss and the presence of vestibular loss (p < 0.001), with 59% (10/17) vestibular losses in the group of hearing-impaired children compared to 4% (3/76) in the group of normal-hearing subjects. In the majority of the cases with a vestibular dysfunction (85%, 11/13), both the semicircular canal system and the otolith system were affected. The remaining subjects (15%, 2/13) had an isolated semicircular canal dysfunction. Sixty-one patients already had at least one follow-up examination. Deterioration of the vestibular function was detected in 6 of them (10%, 6/61).
cCMV can impair not only the auditory but also the vestibular function. Similar to the hearing loss, vestibular loss in cCMV can be highly variable. It can be unilateral or bilateral, limited or extensive, stable or progressive, and early or delayed in onset. As the vestibular function can deteriorate over time and even normal-hearing subjects can be affected, vestibular evaluation should be part of the standard otolaryngology follow-up in all children with cCMV.