Degenerative disease of the retina. Autosomal recessive transmission but some cases of autosomal dominant transmission have been described.

From a genotypic point of view, 19 subtypes of LCA (acronym for Leber’s Congenital Amaurosis) have been described so far:

-        LCA1: mutation of the GUCY2D gene (17p31.1) [MIM 204 000]

-        LCA2: mutation of the RPE65 gene (1p31) [MIM 204 100]

-        LCA3: mutation of the SPATA7 gene (14q31) [MIM 604 232]

-        LCA4: mutation of the AIPL1 gene (17p13) [MIM 604 393]

-        LCA5: mutation of the LCA5 gene (6q14) [MIM 604 535]

-        LCA6: mutation of the RPGRIP1 gene (14q11) [MIM 613 826]

-        LCA7: mutation of the CRX gene (19q13) [MIM 613 829]

-        LCA8: mutation of the CRB1 gene (1q31) [MIM 613 835]

-        LCA9: mutation of the NMNAT1 gene (1q36) [MIM 608 553]

-        LCA10: mutation of the CEP290 gene (12q21) [MIM 611 755]: responsible of 21 % of the cases (Joubert's syndrome)

-        LCA11:  mutation of the IMPDH1 gene (7q32) [MIM 613 837]

-        LCA12: mutation of the RD3 gene (1q32) [MIM 610 612]

-        LCA13: mutation of the RDH12 gene (14q24) [MIM 612 712]

-        LCA14: mutation of the LRAT gene (4q32) [MIM 613 341]

-        LCA15: mutation of the TULP1 gene (6p21) [MIM 613 843]

-        LCA16: mutation of the KCNJ13 gene (2q37) [MIM 614 186]

-        LCA17: mutation of the GDF6 gene (8q22) [MIM 615 360]

-        LCA18: mutation of the PRPH2 gene (6p21) [MIM 608 133]

-        LCA19: mutation of the USP45 gene (6q16) [MIM 618 513]

The decrease of vision is usually obvious during the neonatal period or early childhood: dilated pupils reacting slowly to light, nystagmus, photophobia.

There are 3 categories of ophtalmologic anomalies:

(1)        retinal aplasia due to an abnormality of the photoreceptors

(2)        early degeneration of the photoreceptors

(3)        photoreceptor dysfunction with a normal retinal anatomy.

At ophthalmoscopy: progressive appearance of a picture of retinitis pigmentosa.

The onset is usually isolated but may be associated with epilepsy or psychomotor retardation. Amaurosis can also be part of a syndrome as Joubert's syndrome (see this term).

Anesthetic implications:

Visual impairment, photophobia. Sometimes epilepsy.

References:

Updated: March 2020