Leber congenital amaurosis

الوصف

Leber congenital amaurosis, also known as LCA, is an eye disorder that is present from birth (congenital). This condition primarily affects the retina, which is the specialized tissue at the back of the eye that detects light and colour. People with this disorder typically have severe visual impairment beginning at birth or shortly afterward. The visual impairment tends to be severe and may worsen over time.

Leber congenital amaurosis is also associated with other vision problems, including an increased sensitivity to light (photophobia), involuntary movements of the eyes (nystagmus), and extreme farsightedness (hyperopia). The pupils, which usually expand and contract in response to the amount of light entering the eye, do not react normally to light. Instead, they expand and contract more slowly than normal, or they may not respond to light at all.

A specific behaviour called Franceschetti's oculo-digital sign is characteristic of Leber congenital amaurosis. This sign consists of affected individuals poking, pressing, and rubbing their eyes with a knuckle or finger. Poking their eyes often results in the sensation of flashes of light called phosphenes. Researchers suspect that this behaviour may contribute to deep-set eyes in affected children.

In very rare cases, delayed development and intellectual disability have been reported in people with the features of Leber congenital amaurosis. Because of the visual loss, affected children may become isolated. Providing children with opportunities to play, hear, touch, understand and other early educational interventions may prevent developmental delays in children with Leber congenital amaurosis.

At least 20 genetic types of Leber congenital amaurosis have been described. The types are distinguished by their genetic cause, patterns of vision loss, and related eye abnormalities.

Inheritance patterns

The source lists the following possible inheritance patterns: Autosomal dominant; Autosomal recessive. More than one pattern can apply in different cases.

Related genes

• PRPH2

• CEP290

• CRB1

• GUCY2D

• RPE65

• GDF6

• CRX

• IMPDH1

• KCNJ13

• TULP1

• LRAT

• IQCB1

• AIPL1

• LCA5

• SPATA7

• RPGRIP1

• NMNAT1

• USP45

• RDH12

• RD3

Other names

Amaurosis, Leber congenital

Congenital amaurosis of retinal origin

Congenital retinal blindness

CRB

Dysgenesis neuroepithelialis retinae

Hereditary epithelial dysplasia of retina

Hereditary retinal aplasia

Heredoretinopathia congenitalis

LCA

Leber abiotrophy

Leber congenital tapetoretinal degeneration

Leber's amaurosis