Albinism

Definition

Albinism is a defect of melanin production that results in little or no color (pigment) in the skin, hair, and eyes.

Alternative Names

Oculocutaneous albinism; Ocular albinism; Hermansky-Pudlak syndrome

Causes, incidence, and risk factors

Albinism occurs when one of several genetic defects makes the body unable to produce or distribute melanin, a natural substance that gives color to your hair, skin, and iris of the eye.

The defects may be passed down through families.

There are two main types of albinism:

• Type 1 albinism is caused by defects that affect production of the pigment, melanin.
• Type 2 albinism is due to a defect in the "P" gene. People with this type have slight coloring at birth.

The most severe form of albinism is called oculocutaneous albinism. People with this type of albinism have white or pink hair, skin, and iris color, as well as vision problems.

Another type of albism, called ocular albinism type 1 (OA1), affects only the eyes. The person's skin and eye colors are usually in the normal range. However, an eye exam will show that there is no coloring in the back of the eye (retina).

Hermansky-Pudlak syndrome (HPS) is a form of albinism caused by a single gene. It can occur with a bleeding disorder, as well as with lung and bowel diseases.

Other complex diseases may lead to loss of coloring in only a certain area (localized albinism). These conditions include:

• Chediak-Higashi syndrome (lack of coloring all over the skin, but not complete)
• Tuberous sclerosis (small areas without skin coloring )
• Waardenburg syndrome (often a lock of hair that grows on the forehead, or no coloring in one or both irises)

Symptoms

A person with albinism will have one of the following symptoms:

• Absence of color in the hair, skin, or iris of the eye
• Lighter-than-normal skin and hair
• Patchy, missing skin color

Many forms of albinism are associated with the following symptoms:

• Crossed eyes (strabismus)
• Light sensitivity (photophobia)
• Rapid eye movements (nystagmus)
• Vision problems, or functional blindness

Signs and tests

Genetic testing offers the most accurate way to diagnose albinism. Such testing is helpful if you have a family history of albinism. It is also useful for certain groups of people who are known to get the disease.

Your doctor may also diagnose the condition based on the appearance of your skin, hair, and eyes. An ophthalmologist should perform a electroretinogram test, which can reveal vision problems related to albinism. A visual evoked potentials test can be very useful when the diagnosis is uncertain.

Treatment

The goal of treatment is to relieve symptoms. Treatment depends on the severity of the disorder.

Treatment involves protecting the skin and eyes from the sun:

• Reduce sunburn risk by avoiding the sun, using sunscreen, and covering up completely with clothing when exposed to the sun.
• Sunscreen should have a high sun protection factor (SPF).
• Sunglasses (UV protected) may relieve light sensitivity.

Glasses are often prescribed to correct vision problems and eye position. Eye muscle surgery is sometimes recommended to correct abnormal eye movements (nystagmus).

Support Groups

National Organization for Albinism and Hypopigmentation -- www.albinism.org

International Albinism Center -- www.med.umn.edu/ophthalmology/centers/albinism/home.html

Hermansky-Pudlak Syndrome Network -- www.hpsnetwork.org

Expectations (prognosis)

Albinism does not usually affect lifespan. Hermansky-Pudlak syndrome can, however, shorten lifespan due to lung disease or bleeding problems.

People with albinism may be limited in their activities because they can't tolerate the sun.

Complications

• Decreased vision, blindness
• Skin cancer

Calling your health care provider

Call your health care provider if you have albinism or symptoms such as light sensitivity that cause discomfort. Also call if you notice any skin changes that might be an early sign of skin cancer.

Prevention

Because albinism is inherited, genetic counseling is important. People with a family history of albinism or hypopigmentation should consider genetic counseling.

References

Summer GS. Albinism: classification, clinical characteristics, and recent findings. Optom Vis Sci. 2009;86:659-662.