Xeroderma pigmentosa is a rare condition passed down through families in which the skin and tissue covering the eye are extremely sensitive to ultraviolet light.

Ultraviolet light -- such as that found in sunlight -- damages the genetic material (DNA) in skin cells. Normally, the body repairs this damage. But in persons with xeroderma pigmentosa, the body does not fix the damage. As a result, the skin gets very thin and patches of varying color (splotchy pigmentation) appear.

The condition also causes spidery blood vessels in the skin (telangiectasia) and skin cancer. Skin cancer often occurs before the child is 5 years old.

• Sunburn that does not heal after just a little bit of sun exposure
• Blistering after just a little bit of sun exposure
• Spider-like blood vessels under the skin
• Patches of discolored skin that get worse
• Crusting of the skin
• Scaling of the skin
• Oozing raw skin surface
• Discomfort when being in bright light (photophobia)

The doctor will perform a physical exam and ask if you have a family history of xeroderma pigmentosa.

An eye exam may show:

• Clouding of the cornea
• Keratitis
• Lid tumors
• Blepharitis

The following tests can help diagnose the condition in a baby before the birth:

• Amniocentesis
• Chorionic villous sampling
• Culture of amniotic cells

The following tests can help diagnose the disorder after the birth of the child:

• Culture of skin fibroblasts
• Skin biopsy

Children with this condition need total protection from sunlight. Even the light coming through windows and fluorescent bulbs is dangerous.

When these children must go out in the sun, they should wear protective clothing.

Wear high protection (SPF 70 or greater) sunscreen and very dark, UV-protected glasses. Your doctor may prescribe medicine to help prevent certain skin cancers.

Xeroderma Pigmentosum Society -- www.xps.org

XP Family Support Group -- www.xpfamilysupport.org

Most persons with this condition die of skin cancer early in adulthood.

• Change in appearance of skin (disfigurement)
• Skin cancer

Call for an appointment with your health care provider if you or your child has symptoms of xeroderma pigmentosa.

Experts recommend genetic counseling for persons with a family history of xeroderma pigmentosa who wish to have children.

Abeloff MD, Armitage JO, Niederhuber JE, Kastan MB, McKena WG. Clinical Oncology. 3rd ed. Orlando, Fl: Churchill Livingstone; 2004.

Kumar V, Abbas AK, Fausto N. Robbins and Cotran Pathologic Basis of Disease. 7th ed. St. Louis, Mo: WB Saunders; 2005.