Sorbitol dehydrogenase deficiency with peripheral neuropathy (SORDD) is an autosomal recessive disorder characterized by onset of distal muscle weakness mainly affecting the lower limbs and resulting in difficulty walking. Onset of symptoms is usually in the first or second decades of life, although later adult onset has been reported; the disorder is slowly progressive. Nerve conduction velocities are most consistent with an axonal process. More variable features include distal sensory impairment, upper limb tremor, and scoliosis. Laboratory studies show increased serum sorbitol (summary by Cortese et al., 2020).