Leber Congenital Amaurosis
Incidence
It is best regarded as a group of genetic conditions most transmitted as autosomal recessive (AR) inheritance. It is responsible for 10 to 20 % of congenital blindness.
Clinical Characteristics
There is congenital blindness, roving eye movements, or nystagmus. May have saccadic palsy similar to ocular motor apraxia. Fundi is frequently normal in infancy but optic atrophy and atypical retinitis pigmentosa usually appears late in infancy or childhood. There are variable neurological deficits present associated with each such as hipotonia, mental retardation, seizures, deafness, occasional polycystic renal disease or hepatomegaly with absent peroxisomes. Absent ERG. In older children, there is typical retinitis pigmentosa. On CT, there is hipoplasia of cerebellar vermis and polymicrogyria reported. A sibship with hyperthreoninemia and hyperthreoninuria has been described.
Precipitants
no
Provocation Tests
no
Diagnostic Procedures
ERG flat, absent. May have abnormal aminoacids (hyperthreoninemia and hyperthreoninuria has been described).