Ataxia, Spastic, Childhood-Onset, Autosomal Recessive, With Optic Atrophy And Mental Retardation

Description

This progressive neurodegenerative disorder is characterized by early childhood onset of spastic ataxia with mental retardation, cerebellar signs, and variable optic atrophy (Hogan and Bauman, 1977).

Clinical Features

Hogan and Bauman (1977) reported 4 unrelated patients with early childhood onset of a progressive neurologic disorder characterized by delayed psychomotor development, spastic ataxia affecting the upper and lower limbs, and later onset of nystagmus and dysarthria. All had a wide-based gait and signs of cerebellar dysfunction, including tremor, dysmetria, and poor coordination of rapid alternating movements and fine finger movements. Hyperreflexia and ankle clonus were commonly present. Three patients had optic atrophy, 2 also with sensorineural hearing loss. Three patients had abnormal EEG findings during sleep, although overt seizures were not reported. Two patients also had evidence of a peripheral neuropathy. Three patients had abnormal EEG findings during sleep, although overt seizures were not reported. Two patients had sibs who were less severely affected. It is difficult to know whether this was distinct from other recessive cerebellar disorders, and Hogan and Bauman (1977) noted overlap with Behr syndrome (210000).

Senanayake (1992) described an 11-year-old girl who had developed spasticity, ataxia, internuclear ophthalmoplegia, dementia, and startle myoclonus at the age of 5 years. The deep tendon reflexes were exaggerated. Computed tomography showed generalized cerebellar atrophy. Her asymptomatic younger brother had early bilateral optic atrophy. The proband was the eldest of 3 children whose parents were first cousins. The cases of Senanayake (1992) were similar to those described by Van Bogaert and Martin (1974); see 271250. There were similarities to a partial hexosaminidase A deficiency (272800), 3-methylglutaconic aciduria III (258501), and adult Leigh disease (161700). However, no biochemical data were presented.

Inheritance

Consanguinity in 1 family and affected sibs in another family reported by Hogan and Bauman (1977) suggested autosomal recessive inheritance of this form of spastic ataxia.