[A case of hereditary motor and sensory neuropathy with congenital cataract and mental retardation].

A 6-year-old boy with hereditary motor and sensory neuropathy (HMSN), congenital cataract and mental retardation was reported. The condition commenced with distal weakness and wasting of lower limbs. Subsequently marked right pes cavus and equinovarus deformity appeared. Motor and sensory conduction velocities in the limbs were slowed. Pathological examination of biopsied sural nerve showed significant loss of large myelinated fibers. Neither demyelination nor onion bulbs were observed. For clinical and neuropathological findings, the present case did not fit in with previously reported cases of HMSN. The case was classified as a new variant of HMSN type II.