Schindler disease, a rare autosomal recessive disorder, occurs with two main clinical phenotypes. Type 1 disease is an infantile neuroaxonal dystrophy in which there is neurological degeneration resulting in psychomotor retardation, blindness and myoclonic seizures. In type 2 disease there is mild mental retardation and angiokeratoma corporis diffusum. Since so few patients have been described, the full clinical spectrum of severity remains unknown.
Deficiency of a-N-acetylgalactosaminidase is the basic defect.