Nervous system involvement in Farber disease.

A 30 months-old boy with Farber disease developed nystagmus 12 months after hematopoietic stem cell transplantation (HSCT). At 40 months, gait ataxia was evident, and brain MRI showed increased size of pericerebellar sulci and 4th ventricle. EMG showed denervation in the tongue and upper limb muscles, consistent with motor neuron disease. HSCT improves the peripheral manifestations of Farber disease, but may not prevent the progressive neurological deterioration.