(Hypopigmentation; Oculocutaneous Albinism; Ocular Albinism)
Definition
Definition
Albinism refers to a group of rare inherited disorders that are present from birth. Albinism affects the amount of pigment found in the skin, hair, and eyes. People with albinism usually have little to no pigment in their eyes, skin, and hair. The degree of pigment loss can be quite variable. There are different types of albinism:
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Oculocutaneous albinism
- Type 1—complete absence of pigment. Skin, hair, and eyes lack all pigment from birth. Freckles or moles will not appear at any time during their lifetimes. This group is divided into several subtypes depending on associated characteristics.
- Type 2—decreased pigment, but may still have freckles and moles. This form of albinism is more common among persons of African descent. This form may be associated with such minor pigment loss that it is noticed only by looking at differences among other non-affected family members.
- Both Type 1 and Type 2 albinism are usually associated with visual problems including nystagmus (abnormal jumping movements of the eyes) and decreased visual acuity, which is frequently not fully improved with glasses or contact lenses.
- Type 3—reddish brown skin, reddish hair, and hazel or brown eyes, generally black South Africans
- Type 4––similar to type 2, predominantly in Japanese persons
- Ocular albinism––an X-linked albinism where there are vision problems without changes in skin or hair
- Hermansky-Pudlak––in addition to albinism, persons also have lung, bowel, and bleeding problems
- Chediak-Higashi––in addition to albinism, persons also have immune problems with defects in the immune system
Causes
Causes
Albinism is caused by altered genes. The affected genes control the body’s ability to make a pigment called melanin.
Altered genes are most often inherited from parents. Both parents will need to have the altered genes in order for the child to develop most types of albinism.
People can carry one set of altered genes and not have signs of albinism. They are called carriers. The second, healthy set of genes prevents the disease from developing.
Risk Factors
Risk Factors
Albinism is a hereditary disorder. People at risk of inheriting albinism are:
- Children of parents who have albinism
- Children of parents who do not have albinism, but carry the altered genes that cause this disorder
- A positive family history for albinism in a sibling or other relative
Albinism is rare. All races are affected, though Type 1 occurs predominantly in Caucasians and Type 2 in African Americans. Most children with albinism are born to parents with normal hair and skin color for their ethnic background.
Symptoms
Symptoms
The symptoms of albinism depend on the specific type of albinism. Some types affect the skin, hair, and eyes. Other types affect only the eyes or only the skin.
Eye Symptom—StrabismusCopyright © Nucleus Medical Media, Inc.
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Symptoms may include:
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Eye problems, such as:
- Strabismus or crossed or wandering eye
- Poor vision that usually cannot be fully corrected with glasses or contacts
- In some cases, functional blindness
- Nystagmus or irregular, rapid eye movement
- Amblyopia or “lazy” eye
- Photophobia–sensitivity to bright lights or glare
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Skin problems, including:
- Little or no pigmentation resulting in extremely light or white skin
- Extreme sensitivity to sunburn
- Very high susceptibility to skin cancer
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Hair problems, including:
- White hair
- Lighter than expected hair (often the forelock) being white
- Certain rare types of albinism, such as Hermansky-Pudlak syndrome, can cause other symptoms.
Diagnosis
Diagnosis
In many types of albinism, the disorder can be diagnosed by observing major or total absence of pigmentation of the hair, skin, and eyes and by vision problems. Most types of albinism affect the eyes. Certain eye tests (including an electroretinogram) are used to help confirm the diagnosis. For some types of albinism, DNA genetic testing can also be used to confirm the diagnosis.
While albinism is always visible at birth, it may be so mild that affected persons are unaware of their diagnosis unless abnormal eye movements or vision develop.
Prognosis
- People with the most common forms of Type 1 and Type 2 albinism and ocular albinism have a normal lifespan.
- An increased risk of skin cancer exists. With careful monitoring, this risk can be reduced. Since melanoma skin cancer may occur, it is important to have frequent skin exams by a dermatologist (skin specialist).
- Affected people usually have unaffected children unless married to another individual with albinism.
- Albinism does not cause a delay in development or intellectual disability.
Treatment
Treatment
There is no cure for albinism. Treatment is aimed at preventing or limiting symptoms. In some cases, specific treatment for certain symptoms is needed.
Preventive Treatment
Preventive treatment may include:
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Protect the skin:
- Sunburn and skin cancer risks can be reduced by avoiding the sun as much as possible
- Wear sunscreen with SPF 30 or higher with UVA and UVB protection
- Cover as much skin as possible with clothing when exposed to the sun
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Protect the eyes:
- Wear sunglasses with UV protection whenever exposed to the sun
- Sunglasses (UV protected) may relieve sensitivity to light
Specific Treatment of Symptoms
Specific treatment of symptoms for albinism may include:
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For eyes:
- Glasses, contacts, and/or optical aids to help improve vision
- Surgery to correct certain eye problems, including crossed eyes or “lazy” eye
- Visual aids (in the classroom) to help children with albinism
- For skin: Surgery to treat and/or remove skin cancer, if necessary
Prevention
Prevention
There is no known way to prevent albinism. If you have albinism or have a family history of the disorder, you can talk to a genetic counselor when deciding to have children to understand the risks to your offspring.
RESOURCES:
National Organization for Albinism and Hypopigmentation (NOAH) http://www.albinism.org
CANADIAN RESOURCES:
Canadian Ophthalmological Society http://www.eyesite.ca
References:
Perry PK, Silverberg NB. Cutaneous malignancy in albinism. Cutis. 2001 May;67(5):427-430.
Rees JL. Genetics of hair and skin color. Annu Rev Genet. 2003;37:67-90.
Surace EM, Domenici L, et al. Amelioration of both functional and morphological abnormalities in the retina of a mouse model of ocular albinism following AAV-mediated gene transfer. Mol Ther. 2005 Oct;12(4):652-658.
Last Updated: 12/20/2014