Congenital Unilateral Hearing Loss: Characteristics and Etiological Analysis in 121 Patients

Abstract

Objective: To describe the characteristics and etiological analysis in patients with congenital unilateral hearing loss. Study design: Retrospective cohort analysis. Setting: Tertiary referral center. Patients: Children with permanent congenital unilateral hearing loss born between 2007 and 2018. Patients were referred after universal newborn hearing screening or by a colleague to confirm the diagnosis and perform etiological examinations. Main outcome measures: Hearing loss type, severity, and evolution linked with the results of etiological testing. Results: In the 121 included children, aural atresia is the leading cause of congenital unilateral hearing loss (32%), followed by structural anomalies (19%) and cCMV (13%), whereas 24% remained idiopathic after etiological work-up. Severity is mainly moderately severe (33% with 56-70 dB hearing loss, majority aural atresia) or profound (31% with > 90 dB hearing loss, predominantly cochlear nerve deficiency).Syndromic features were present in 26%. Although discussed with all parents, only 26% of the children regularly used hearing amplification. Conclusions: Congenital conductive unilateral hearing loss is mainly caused by aural atresia, which proportion in congenital unilateral hearing loss proved higher than previously reported. Cochlear nerve deficiency and cCMV are the predominant etiologies of congenital unilateral sensorineural hearing loss. Etiological work-up in affected patients is mandatory as it might impact the approach, and syndromic features should be actively searched for.

Impact of unilateral hearing loss in early development

“…Most cases of UHL are congenital, or early onset [19] and are predominantly sensorineural in nature. Congenital sensorineural UHL is often related to cochlear nerve deficiency (or other structural inner ear anomalies), or congenital cytomegalovirus (CMV) infection, although many other potential origins have been identified [3,16,18]. Congenital conductive UHL in kids accounts for up to one quarter of UHL cases and is primarily related to aural atresia [16,20].…”

“…Congenital conductive UHL in kids accounts for up to one quarter of UHL cases and is primarily related to aural atresia [16,20]. Progressive, or delayed onset UHL, as might occur with enlarged vestibular aqueduct syndrome or CMV, for example, is also known to occur [16,19,21]. Despite adequate work-up, the cause may remain unknown for a large proportion of children [16,22].…”

“…Progressive, or delayed onset UHL, as might occur with enlarged vestibular aqueduct syndrome or CMV, for example, is also known to occur [16,19,21]. Despite adequate work-up, the cause may remain unknown for a large proportion of children [16,22].…”

“…UHL affects 3-6% of school-aged children in the USA [2,12,13] and may be caused by a number of congenital and acquired etiologies [14,15 && , [16][17][18]. Most cases of UHL are congenital, or early onset [19] and are predominantly sensorineural in nature.…”

Trajectory of hearing loss in children with unilateral hearing loss

“…Our previous research on a cohort of children with bilateral/unilateral loss found no significant association between risk indicators and progressive loss except that children with craniofacial anomalies were more likely to have stable hearing loss ( 24 ). Permanent conductive (structural) loss, generally associated with craniofacial anomalies such as aural atresia has been reported in 25%–33% of children with UHL ( 2 , 43 ). Onset of hearing loss, which can be related to etiology, and type and severity of hearing loss at diagnosis have also not been well-investigated in relation to progressive hearing loss.…”