Identical male twins and brother with Cockayne syndrome.

The clinical, radiological, and neuropathological findings in early onset Cockayne syndrome are illustrated in identical twins and their brother. Their appearance of dwarfism with small head and prominent beaked nose strongly resembled that seen in the Seckel syndrome, but unlike patients with that syndrome they had a normal birth weight (for twins), thick cranial vaults, intracranial calcification, and a severe degree of mental retardation. The twins were deaf and blind, with optic atrophy and retinal pigmentation, while their brother had cataracts. Their hands and feet were large in proportion to their small trunk. They had cutaneous sensitivity to any slight exposure to ultraviolet light and severe neurologic problems with incoordination and spasticity. Radiologic findings included microcephaly, a thick cranial vault, a small pelvis, coxa valga, and "ivory epiphyses" in terminal phalanges of hands and feet. Pathologic findings included atrophy of white matter with widespread patchy demyelination, and massive siderocalcific deposits in the brain, particularly in the basal ganglia and cerebellum. While autosomal recessive inheritance is most likely, formally X-linked inheritance cannot be excluded.