NIH Rare Diseases :
52
The following summary is from Orphanet , a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 1490 Definition Corneal dystrophy-perceptive deafness (CDPD) or Harboyan syndrome is a degenerative corneal disorder characterized by the association of congenital hereditary endothelial dystrophy (CHED; see this term) with progressive, postlingual sensorineural hearing loss . Epidemiology To date, 24 cases from 11 families of various origins (Asian Indian, South American Indian, Sephardi Jewish, Brazilian Portuguese, Dutch, Gypsy, Moroccan and Dominican) have been reported. Clinical description The ocular manifestations in CDPD include diffuse bilateral corneal edema occurring with severe corneal clouding, blurred vision, visual loss and nystagmus . They are apparent at birth or within the neonatal period and are indistinguishable from the ocular findings characterizing autosomal recessive CHED (CHED2). Hearing deficit in CDPD is slowly progressive and is typically identified in patients between 10 and 25 years of age. There are no reported cases with prelingual deafness, however, significant hearing loss in children as young as 4 years old has been detected by audiometry, suggesting that hearing may be affected early in the disease course, even at birth. Etiology CDPD is caused by mutations in the SLC4A11 gene located at the CHED2 locus on chromosome 20p13-p12, indicating that CHED2 and CDPD are allelic disorders. A total of 62 different SLC4A11 mutations have been reported in 98 families (92 with CHED2 and six with CDPD). Diagnostic methods Diagnosis is based on clinical criteria, detailed ophthalmological assessment and audiometry. Molecular confirmation of the clinical diagnosis is feasible. Differential diagnosis A variety of genetic, metabolic, developmental and acquired diseases presenting with clouding of the cornea should be considered in the differential diagnosis (Peters anomaly, sclerocornea, limbal dermoids and congenital glaucoma ; see these terms). Audiometry must be performed to differentiate CDPD from CHED2. Autosomal recessive types of CHED (CHED2) and CDPD should be carefully distinguished from the less severe autosomal dominant type, CHED1. Genetic counseling More than 50% of the reported CDPD cases have been associated with parental consanguinity and all reported cases have been consistent with autosomal recessive transmission. Management and treatment The ocular abnormalities in patients with CDPD may be treated with topical hyperosmolar solutions. However, corneal transplantation (penetrating keratoplasty) represents the definitive treatment. Corneal transplantation results in substantial visual gains and has a relatively good surgical prognosis . Audiometric monitoring should be offered to all patients. Hearing aids may be necessary in adolescence. Visit the Orphanet disease page for more resources.
MalaCards based summary :
Corneal Dystrophy and Perceptive Deafness, also known as
corneal dystrophy-perceptive deafness syndrome, is related to
corneal dystrophy and
corneal endothelial dystrophy. An important gene associated with Corneal Dystrophy and Perceptive Deafness is
SLC4A11 (Solute Carrier Family 4 Member 11), and among its related pathways/superpathways are
Transport of glucose and other sugars, bile salts and organic acids, metal ions and amine compounds and
O2/CO2 exchange in erythrocytes. Affiliated tissues include
endothelial,
eye and
brain, and related phenotypes are
corneal opacity and
sensorineural hearing impairment
Disease Ontology :
12
A syndrome characterized by congenital corneal endothelial dystrophy and progressive, postlingual sensorineural hearing loss that has material basis in homozygous or compound heterozygous mutation in SLC4A11 on chromosome 20p13.
OMIM :
56
Harboyan syndrome, or corneal dystrophy and perceptive deafness (CDPD), consists of congenital corneal endothelial dystrophy and progressive sensorineural deafness, and is transmitted as an autosomal recessive trait (summary by Desir et al., 2007).
(217400)
UniProtKB/Swiss-Prot :
73
Corneal dystrophy and perceptive deafness: An ocular disease characterized by the association of corneal clouding with progressive perceptive hearing loss.