Xeroderma pigmentosum

Xeroderma pigmentosum
Other namesDeSanctis-Cacchione syndrome[1][2]

XP1 / XP2 / XP3 / XP4 / XP5 / XP6 / XP7[3]

Xeroderma pigmentosum I/II/III/IV/V/VI/VII[3]

Xeroderma pigmentosum complementation group A/B/C/D/E/F/G[3]

xeroderma pigmentosum group A/B/C/D/E/F/G[3]
An eight-year-old girl from Guatemala with xeroderma pigmentosum[4]
SpecialtyMedical genetics
SymptomsSevere sunburn after only a few minutes in the sun, freckling in sun-exposed areas, dry skin, changes in skin pigmentation[1]
ComplicationsSkin cancer, brain cancer, cataracts[1]
Usual onsetBecomes visible ~6 months of age[2]
DurationLifelong
CausesGenetic disorder (autosomal recessive)[1]
Diagnostic methodBased on symptoms and confirmed by genetic testing[5]
Differential diagnosisTrichothiodystrophy, Cockayne syndrome, cerebrooculofacioskeletal syndrome, erythropoietic protoporphyria[6]
PreventionNo cure available
TreatmentCompletely avoiding sun or UV rays, retinoid creams, vitamin D[5][6]
PrognosisLife expectancy is shortened by about 30 years.[7]
Frequency• 1 in 100,000 (worldwide)[3]

• 1 in 370 (India) [citation needed]

• 1 in 22,000 (Japan)[3]

• 1 in 250,000 (US)[8]

• 1 in 430,000 (Europe)

• 1 in 1,000,000 (UK)[3]

Xeroderma pigmentosum (XP) is a genetic disorder in which there is a decreased ability to repair DNA damage such as that caused by ultraviolet (UV) light.[1] Symptoms may include a severe sunburn after only a few minutes in the sun, freckling in sun-exposed areas, dry skin and changes in skin pigmentation.[1] Nervous system problems, such as hearing loss, poor coordination, loss of intellectual function and seizures, may also occur.[1] Complications include a high risk of skin cancer, with about half having skin cancer by age 10 without preventative efforts, and cataracts.[1] There may be a higher risk of other cancers such as brain cancers.[1]

XP is autosomal recessive, with mutations in at least nine specific genes able to result in the condition.[1][6] Normally, the damage to DNA which occurs in skin cells from exposure to UV light is repaired by nucleotide excision repair.[1] In people with xeroderma pigmentosum, this damage is not repaired.[1] As more abnormalities form in DNA, cells malfunction and eventually become cancerous or die.[1] Diagnosis is typically suspected based on symptoms and confirmed by genetic testing.[5]

There is no cure for XP.[6] Treatment involves completely avoiding the sun.[6] This includes protective clothing, sunscreen and dark sunglasses when out in the sun.[6] Retinoid creams may help decrease the risk of skin cancer.[6] Vitamin D supplementation is generally required.[5] If skin cancer occurs, it is treated in the usual way.[6] The life expectancy of those with the condition is about 30 years less than normal.[7]

The disease affects about 1 in 100,000 worldwide.[3] By region, it affects about 1 in 370 in India, 1 in 20,000 in Japan, 1 in 250,000 people in the United States and 1 in 430,000 in Europe.[8] It occurs equally commonly in males and females.[9] Xeroderma pigmentosum was first described in the 1870s by Moritz Kaposi.[5][9] In 1882, Kaposi coined the term xeroderma pigmentosum for the condition, referring to its characteristic dry, pigmented skin.[9] Individuals with the disease have been referred to as "children of the night" or "moon children".[10]

  1. ^ a b c d e f g h i j k l m "Xeroderma pigmentosum". Genetics Home Reference. U.S. Library of Medicine. 26 June 2018. Retrieved 28 June 2018.
  2. ^ a b "Xeroderma pigmentosum". dermnetnz.org. Retrieved 25 February 2020.
  3. ^ a b c d e f g h "Not found". Archived from the original on 2022-10-26. Retrieved 2023-03-06.
  4. ^ Cite error: The named reference Halpern_2008 was invoked but never defined (see the help page).
  5. ^ a b c d e "Xeroderma Pigmentosum". NORD (National Organization for Rare Disorders). 2017. Retrieved 28 June 2018.
  6. ^ a b c d e f g h "Xeroderma pigmentosum". Genetic and Rare Diseases Information Center (GARD). U.S. Department of Health and Human Services. 2018. Retrieved 28 June 2018.
  7. ^ a b Ahmad S, Hanaoka F (2008). Molecular Mechanisms of Xeroderma Pigmentosum. Springer Science & Business Media. p. 17. ISBN 9780387095998.
  8. ^ a b Lehmann AR, McGibbon D, Stefanini M (November 2011). "Xeroderma pigmentosum". Orphanet Journal of Rare Diseases. 6: 70. doi:10.1186/1750-1172-6-70. PMC 3221642. PMID 22044607.
  9. ^ a b c Griffiths C, Barker J, Bleiker T, Chalmers R, Creamer D (2016). Rook's Textbook of Dermatology, 4 Volume Set. John Wiley & Sons. ISBN 9781118441190.
  10. ^ Salway JG (2011). Medical Biochemistry at a Glance. John Wiley & Sons. p. 313. ISBN 9781118292402.