Xeroderma Pigmentosum-Cockayne Syndrome Complex

Xeroderma pigmentosum/Cockayne syndrome complex (XP/CS complex) is characterized by the cutaneous features of xeroderma pigmentosum (XP) (see this term) together with the systemic and neurological features of Cockayne syndrome (CS; see this term).

Epidemiology

Less than 30 cases have been described to date.

Clinical description

The disease manifests during infancy. Patients present with cutaneous UV-sensitive lesions that generally develop into skin cancer, and also develop characteristic CS manifestations such as microcephaly, hydrocephalus, cachexia, premature aging, dwarfism, skin atrophy, arteriosclerosis, progressive hearing loss, cognitive deficit, spasticity, ataxia, pigmentary retinopathy and optic atrophy. In contrast to the neurological abnormalities of XP which are predominantly secondary to neuronal degeneration, in XP/CS complex, dysmyelination typical of CS is observed.

Etiology

Affected individuals have mutations in one of three XP genes: ERCC3 (2q21), ERCC2 (19q13.3), or ERCC5 (13q22-q34). Recently, one patient with XP/CS complex and additional features of Fanconi anemia (see this term) was reported with a mutation in the ERCC4 gene (16p13.3).

Genetic counseling

Transmission is autosomal recessive and genetic counseling is possible.