Cockayne syndrome

Epidemiology

rare

Pathology

• accelerated atherosclerosis
• cachectic dwarfism
• transcription-coupled repair deficiency*
• no apparent increased risk of malignant neoplasms
• delayed neural development & severe progressive neurologic degeneration

* Cells from individuals with Cockayne syndrome are deficient in a subpathway of nucleotide excision repair, transcription-coupled repair.

Genetics

• autosomal recessive disorder
• associated with defects in ERCC8 (type A)
• associated with defects in ERCC6 (type B)

Clinical manifestations

• normal appearance at birth (type 1)
  • severe form (type 2) manifests prenatally
• photosensitivity
• progeroid appearance: loss of adipose tissue resulting in thin, atrophic, hyperpigmented skin, particularly over the face, combined with premature graying of the hair results in a precociously senile appearance
• slow growth, cachectic dwarfism
• pigmentary degeneration of the retina
• optic atrophy
• cataracts
• partial sensorineural deafness
• mental retardation
• large & protruberant ears
• pinched nose
• carious teeth
• cool & sometimes cyanotic hands & feet
• an unsteady gait with tremor
• limitation of joint mobility

Diagnostic procedures

• nerve conduction study
  • may show decreased nerve conduction velocity

Differential diagnosis

• some overlap with certain forms of xeroderma pigmentosum
  • unlike xeroderma pigmentosum
    • not associated with increased freckling & other pigmentation abnormalities in the skin
    • no significant increase in skin cancer

More general terms

• progeroid syndrome
• dwarfism (nanism)
• genetic disease of the eye

Additional terms

• nucleotide excision repair

Database

• OMIM: https://mirror.omim.org/entry/216400
• OMIM: https://mirror.omim.org/entry/133540