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Ichthyosis vulgaris
By Mayo Clinic staffOriginal Article: http://www.mayoclinic.com/health/ichthyosis-vulgaris/DS00734
Definition
Ichthyosis vulgaris, sometimes called fish scale disease or fish skin disease, is an inherited skin disorder in which dead skin cells accumulate in thick, dry scales on your skin's surface. The scales of ichthyosis vulgaris can be present at birth, but usually first appear during early childhood. Sometimes ichthyosis vulgaris disappears entirely for most of the adult years, only to return later.
Most cases of ichthyosis vulgaris are mild, but some are severe. Sometimes other skin diseases are associated with ichthyosis vulgaris, such as the rash-producing atopic dermatitis. No cure has been found for ichthyosis vulgaris, and treatments focus on controlling the condition.
Symptoms
Severity of symptoms may vary widely among family members who have the condition. Symptoms include:
- Dry, scaly skin
- Tile-like, small scales, in polygon shapes
- Scales colored white, dirty gray or brown — with people with darker skin tending to have darker colored scales
- Flaky scalp
- Deep, painful cracks in your palms and soles in severe cases
The scales usually appear on your elbows and lower legs and may be especially thick and dark over your shins. Most cases of ichthyosis vulgaris are mild, but some can be severe.
Symptoms usually worsen or are more pronounced in cold, dry environments and tend to improve or even resolve in warm, humid environments.
Ichthyosis vulgaris is the most common of the ichthyoses, a group of skin diseases characterized by scaliness. Other less common forms of ichthyosis include:
- Lamellar ichthyosis. This severe form is also known as congenital ichthyosiform erythroderma or nonbullous congenital ichthyosiform erythroderma. Present at birth, this form lasts throughout life. Infants with lamellar ichthyosis are born encased in a filmy (collodion) membrane that's shed after 10 to 14 days, revealing skin that's covered in scales. The scales can range from fine and white to thick and dark and generally occur over the entire body, although they may be larger on the legs. Lamellar ichthyosis can be extremely disfiguring and may cause great psychological suffering for children and adults with the disease.
- X-linked ichthyosis. Starting soon after birth, this type of ichthyosis occurs only in males. The noticeable, dirty-brown scales that characterize this skin disease are most pronounced on the back of the neck, on the arms and behind the knees. Symptoms generally don't improve with age.
- Epidermolytic hyperkeratosis. Also known as bullous congenital ichthyosiform erythroderma, this rare form of ichthyosis is usually present at birth and begins with blistering skin. In time, the skin peels away in large sheets and becomes rough or looks like it has warts. The affected skin is most pronounced on the knees, elbows, wrists and other flexural areas.
When to see a doctor
If you suspect you or your child has ichthyosis, talk to your family doctor or a dermatologist. He or she can diagnose the condition by examining the characteristic scales. Also, be sure to seek medical advice if the symptoms worsen or don't improve with self-care measures. You may need stronger medication to manage the condition.
Causes
Ichthyosis vulgaris is characterized by chronic, excessive buildup of the protein in the upper layer of the skin (keratin). This buildup is a result of your skin's natural shedding process being slowed or inhibited.
Ichthyosis vulgaris is most often caused by a genetic mutation, inherited in an autosomal dominant pattern. That means a child has to inherit only one copy of the affected gene to develop the disease. Children with the inherited form of the disorder usually have normal skin at birth, but develop scaling and roughness during the first few years of life. At times, ichthyosis vulgaris may disappear during the adult years, only to return later.
Ichthyosis not caused by genetic abnormalities, referred to as acquired ichthyosis, is rare. This type usually shows up in adulthood. It's usually associated with other diseases, such as cancer, thyroid disease or chronic renal failure.
Complications
Ichthyosis can affect more than the appearance of your skin; it can affect your skin's ability to function normally. As a result, some people with ichthyosis may experience:
- Overheating. In rare cases, ichthyosis interferes with sweating. Skin thickness and scales prevent sweat from reaching the surface of your skin, which inhibits cooling.
- Secondary infection. Skin splitting and cracking may lead to infections, either on your skin or a wider infection in your body.
Preparing for your appointment
If the appointment is for your child, you're likely to start by seeing your child's pediatrician. If the appointment is for you, you're likely to start by seeing your family doctor or a general practitioner. However, in some cases when you call to set up an appointment, you may be referred immediately to a specialist in skin conditions (dermatologist).
Here's some information to help you prepare for the appointment.
What you can do
- Write down any symptoms your child or you are experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
- Write down key personal information, including any major stresses or recent life changes.
- Make a list of all medications, vitamins or supplements you or your child is taking.
- Write down questions to ask your doctor.
Preparing a list of questions for your doctor will help you make the most of your time together. List your questions from most important to least important. For ichthyosis vulgaris, some basic questions to ask your doctor include:
- What is likely causing the symptoms or condition?
- Other than the most likely cause, what are other possible causes?
- What kinds of tests do I or my child need?
- Is the condition likely temporary or chronic?
- What is the best course of action?
- What are the alternatives to the primary approach you're suggesting?
- Are there any restrictions to follow?
- Is there a generic alternative to the medicine you're prescribing?
- Are there any brochures or other printed material that I can take home with me? What Web sites do you recommend?
Don't hesitate to ask other questions at any time during your appointment.
What to expect from your doctor
Your doctor is likely to ask you a number of questions, including:
- When did symptoms appear?
- Have the symptoms been continuous or occasional?
- What, if anything, seems to improve the symptoms?
- What, if anything, appears to worsen the symptoms?
- Does anyone in your immediate or extended family have similar skin changes?
What you can do in the meantime
To help soothe your or your child's skin:
- Wash only with mild soaps that have added oils and fats. Avoid deodorant and antibacterial soaps, which are especially harsh on dry skin.
- Apply moisturizer or lubricating cream while your or your child's skin is still moist from bathing. Choose a moisturizer that contains urea or propylene glycol — chemicals that help keep your skin moist. Petroleum jelly is another good choice. Cover the treated areas with plastic wrap to keep the petroleum jelly from staining clothes and furniture.
Tests and diagnosis
A doctor can often make a diagnosis by examining your skin and the characteristic scales. If there's any doubt, he or she may perform other tests, such as a skin biopsy. This may be necessary to rule out other causes of dry, scaly skin.
To diagnose ichthyosis, your doctor also will take into account:
- Personal and family history of ichthyosis
- Age when ichthyosis first started
- Presence of other skin disorders
Treatments and drugs
There's no known cure for ichthyosis, so the goal of treatment is to manage the condition.
Medications
Treatments may include:
- Alpha hydroxy acids, such as lactic acid and glycolic acid. Treatment can include prescription creams and ointments that contain acids that help control scaling and increase skin moisture.
- Retinoids. Your doctor may proscribe these vitamin A-derived medications in severe cases. They reduce the production of skin cells. Side effects from the medication may include eye and lip inflammation, bone spurs and hair loss, as well as birth defects if taken during pregnancy.
Lifestyle and home remedies
Although self-help measures won't cure ichthyosis, they may help improve the appearance and feel of damaged skin. Consider these measures to help:
- Take long soaking baths to soften the skin. Then use a rough-textured sponge, such as a loofa sponge, to remove the thickened scales.
- Choose mild soaps that have added oils and fats. Avoid deodorant and antibacterial soaps, which are especially harsh on dry skin.
- After showering or bathing, gently pat or blot your skin dry with a towel so that some moisture remains on the skin.
- Apply moisturizer or lubricating cream while your skin is still moist from bathing. Choose a moisturizer that contains urea or propylene glycol — chemicals that help keep your skin moist. Petroleum jelly is another good choice. Cover the treated areas with plastic wrap to keep the petroleum jelly from staining clothes and furniture.
- Apply an over-the-counter product that contains urea, lactic acid or a low concentration of salicylic acid twice daily. Mild acidic compounds help your skin shed its dead skin cells. Urea helps bind moisture to your skin.
- Use a portable home humidifier or one attached to your furnace to add moisture to the air inside your home.
Coping and support
Because ichthyosis vulgaris affects the appearance of your skin, it can be difficult to cope with the condition. Ask your doctor about support groups in your area. Or it might be helpful to talk to a counselor.
- About ichthyosis: FAQ. Foundation for Ichthyosis & Related Skin Types. http://www.scalyskin.org/column.cfm?ColumnID=13. Accessed April 4, 2010.
- Okulicz JF, et al. Hereditary and acquired ichthyosis vulgaris. International Journal of Dermatology 2003;42:95.
- Fleckman P, et al. The ichthyoses. In: Wolff K, et al. Fitzpatrick's Dermatology in General Medicine. 7th ed. New York, N.Y.: McGraw-Hill Medical; 2008. http://www.accessmedicine.com/content.aspx?aID=2977821. Accessed April 5, 2010.

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