Causes and Treatments
Ichthyosis is a group of skin diseases that causes extremely dry, thick, and scaly skin. The skin often looks like it has fish scales. Although there are over 20 kinds of ichthyosis, approximately 95% of people who have a form of the disease have the mildest form, ichthyosis vulgaris, also known as ichthyosis simplex.
Who Gets Ichthyosis Vulgaris?
Ichthyosis vulgaris, commonly referred to as just ichthyosis, typically begins in childhood, between 3 months and 5 years of age. Children usually develop it because they have inherited a gene(s) for the disease from one or both parents. Because it is passed through the genes, this type is called inherited ichthyosis vulgaris.
Adults may also develop ichthyosis, but this is far less common. Adults typically get acquired ichthyosis vulgaris, which occurs when a disease or medication causes it to develop. Diseases that can trigger ichthyosis include kidney failure, some cancers, and human immunodeficiency virus (HIV).
Whether ichthyosis vulgaris begins in childhood or adulthood, it can be so mild that it is mistaken for extremely dry skin. Many people never realize they have ichthyosis because applying moisturizer keeps their skin free of scales.
Ichthyosis affects all races and both sexes equally.
Image used with permission of Journal of the American Academy of Dermatology: J Am Acad Dermatol. 2006; 55:647-56.
What Causes Ichthyosis?
The gene responsible for normal skin development may be faulty in one or both parents, or it can mutate while the baby is developing in the womb, causing a deficiency in filaggrin. Filaggrin is a protein that is necessary to create a healthy outer layer of skin.
Without enough filaggrin, the body cannot shed skin cells as it should. As older skin cells build up on the skin’s surface, the skin thickens and becomes scaly.
Symptoms of Ichthyosis
Ichthyosis is characterized by dry, itchy, scaly, and thickened skin. Scales tend to be white, gray, or brown and typically appear on the front of the legs, back of the arms, scalp, back, or stomach. Thickened skin usually occurs on the palms of the hands and soles of the feet.
You may also develop keratosis pilaris, or rough bumps on the skin, particularly the arms, thighs and buttocks. Symptoms tend to worsen in the winter when air is cold and dry.
In cases of severe ichthyosis, deep cracks can form on the palms and soles and become infected. In addition, you may not be able to sweat normally, which can cause you to overheat.
Treatment for Ichthyosis
Since there is no cure for inherited ichthyosis vulgaris, treatment focuses on managing the disease and lessening the symptoms. Your Water’s Edge Dermatology practitioner will recommend ways to reduce the scale and dry skin.
Soaking in a warm bath can help hydrate your skin and soften the scale. You can then slough off the scale by gently rubbing it with an abrasive sponge, buff puff, or pumice stone.
You should apply moisturizer to damp skin within 2 minutes of bathing to seal in water from a bath or shower. Moisturizers that contain an active ingredient like urea, alpha hydroxyl acid, or lactic acid can also help reduce scale. You should also apply petroleum jelly to deep cracks in thickened skin.
When to See a Dermatologist
If applying moisturizer twice a day fails to get rid of your scaly skin, you should see a dermatologist to find out if you have ichthyosis or another skin condition.
If your skin is cracking, it is important to consult a dermatologist to avoid secondary infection. If you develop a skin infection, your Water’s Edge Dermatology practitioner can prescribe an oral or topical medication to treat it.