A novel case of Heimler syndrome in a young child with compound heterozygous PEX26 mutations: clinical and genetic insights with literature review.
Aurore Aziz, Tristan Bernard-Cuisinier, Daniele Denis et al.
✦ AI-curated · Sources linked
Case in brief
A male infant born at 36 weeks had congenital bilateral sensorineural hearing loss, confirmed by abnormal auditory brainstem responses, and received bilateral cochlear implants. Poor visual behavior prompted ophthalmologic assessment, which showed peripheral retinal “salt-and-pepper” changes and markedly attenuated vessels. Full-field electroretinography showed severely reduced responses, and optical coherence tomography demonstrated abnormal retinal layering. Trio whole-exome sequencing identified two novel compound heterozygous PEX26 variants. The findings supported a diagnosis of Heimler syndrome, a peroxisomal biogenesis disorder; the report describes early cochlear implantation but does not state a visual outcome.
What made this case unusual
The combination of congenital hearing loss with early visual abnormalities, including distinctive peripheral retinal changes and abnormal retinal layering, led to identification of Heimler syndrome associated with two novel compound heterozygous PEX26 variants.
Diagnostic / clinical pearl
In a child with congenital sensorineural hearing loss and poor visual behavior, retinal examination and imaging, alongside genetic testing, can help identify Heimler syndrome.