Corneal dystrophy-perceptive deafness syndrome, also known as Harboyan syndrome, is a rare genetic disorder characterized by congenital hereditary corneal dystrophy that occurs alongside progressive hearing loss of post-lingual onset.[2]
Signs and symptoms
The following is a list of the symptoms people with this condition exhibit:[3]
- Corneal dystrophy
- Clouding of the cornea
- Nystagmus
- Blurry vision
- Generalized vision impairment
- Progressive post-lingual hearing loss
The latter usually appears between the ages of 20 and 30 years old.[4]
Complications
The hearing loss and visual impairment associated with this condition can cause difficulties with living.
Treatment
Although this condition has no cure, it can be treated.
Hearing loss
- Hearing aids
- Cochlear implant
Corneal dystrophy[5]
- Contact lenses
- Corneal transplant
Diagnosis
A diagnosis can be made by general symptom examination and with both ophthalmologic and audiometric studies.
Genetics
This condition is caused by mutations in the SLC4A11 gene which are inherited in an autosomal recessive manner (most of the time).[6][7] Desir et al. (2007) identified mutations in this gene in 6 families, of which 3 were consanguineous and 3 weren't, they found homozygosity for the mutation in the consanguineous families and compound heterozygosity in the non-consanguineous families.[8]
Prevalence
According to OrphaNet, only 24 cases from 11 families across the world have been described in medical literature, these families' origins were very diverse, including Indigenous South American, Sephardic Jewish, Brazilian (of Portuguese descent), Dutch, Romani, Moroccan, and Dominican.[9]