X-linked Malformation Deafness: Neurodevelopmental Symptoms Are Common in Children With IP3 Malformation and Mutation
Henrik Smeds1,2,3, Jeremy Wales1,2,3, Eva Karltorp1,2
1Department of Clinical Science, Intervention and Technology, Karolinska Institute, Stockholm, Sweden.
Insights
Children with Incomplete Partition type 3 (IP3) malformation deafness often experience neurodevelopmental and mental health challenges alongside hearing loss. Early, comprehensive multidisciplinary support is crucial for their habilitation.
Area of Science:
- Otolaryngology
- Genetics
- Neurodevelopmental Pediatrics
Background:
- Incomplete Partition type 3 (IP3) malformation is a rare cause of severe to profound mixed hearing loss.
- Cochlear implantation is a potential hearing restoration option for affected children.
- Limited understanding exists regarding associated neurodevelopmental symptoms in IP3 malformation deafness.
Purpose of the Study:
- To investigate the neurodevelopmental and mental health outcomes in children with IP3 malformation deafness.
- To compare these outcomes with a control group of children with cochlear implants due to GJB2 gene mutations.
Main Methods:
- Retrospective chart review and multidisciplinary assessment of 10 children with IP3 malformation deafness and cochlear implants.
- Comparison with 10 age- and cochlear implant-matched controls with GJB2 gene mutations.
- Evaluation of hearing, language, cognition, and mental ill-health.
Main Results:
- Nine out of 10 IP3 malformation cases had POU3F4 mutations.
- Children with IP3 malformation showed poor speech recognition (especially in noise), executive dysfunction, speech delays, and atypical language/pragmatic skills.
- Parents reported concerns about psychosocial well-being; 80% had high nonverbal cognitive ability despite other deficits.
Conclusions:
- Cochlear implantation is viable for IP3 malformation deafness.
- Associated neurodevelopmental anomalies (e.g., ADHD, DLD) and mental ill-health require extensive multidisciplinary support.
- A consistent, multidisciplinary approach is essential for the comprehensive habilitation of these children.
Objective:
Incomplete partition type 3 (IP3) malformation deafness is a rare hereditary cause of congenital or rapid progressive hearing loss. The children present with a severe to profound mixed hearing loss and temporal bone imaging show a typical inner ear malformation classified as IP3. Cochlear implantation is one option of hearing restoration in severe cases. Little is known about other specific difficulties these children might exhibit, for instance possible neurodevelopmental symptoms.
Material And Methods:
Ten 2; 0 to 9; 6-year-old children with IP3 malformation deafness (nine boys and one girl) with cochlear implants were evaluated with a retrospective chart review in combination with an additional extensive multidisciplinary assessment day. Hearing, language, cognition, and mental ill-health were compared with a control group of ten 1; 6 to 14; 5-year-old children with cochlear implants (seven boys and three girls) with another genetic cause of deafness, mutations in the GJB2 gene.
Results:
Mutations in POU3F4 were found in nine of the 10 children with IP3 malformation. Children with IP3 malformation deafness had an atypical outcome with low level of speech recognition (especially in noise), executive functioning deficits, delayed or impaired speech as well as atypical lexical-semantic and pragmatic abilities, and exhibited mental ill-health issues. Parents of children with IP3 malformation were more likely to report that they were worried about their child's psychosocial wellbeing. Controls, however, had more age-typical results in all these domains. Eight of 10 children in the experimental group had high nonverbal cognitive ability despite their broad range of neurodevelopmental symptoms.
Conclusions:
While cochlear implantation is a feasible alternative for children with IP3 malformation deafness, co-occurring neurodevelopmental anomalies, such as attention deficit hyperactivity or developmental language disorder, and mental ill-health issues require an extensive and consistent multidisciplinary team approach during childhood to support their overall habilitation.
