What Is Ichthyosis?
Ichthyosis is a group of about 30 skin conditions that cause skin dryness and scaling. The condition gets its name from the Greek word for fish because the skin looks like fish scales. You might also hear it called fish scale or fish skin disease.
People with this condition lose the protective barrier that keeps moisture in their skin. They also make new skin cells too quickly or shed old cells too slowly. This leads to a buildup of thick, scaly skin. Most cases of ichthyosis are mild, but it can be more severe. Some types of ichthyosis can affect your other organs, too.
Ichthyosis can't be cured, but treatments can relieve the scaling and make you feel more comfortable.
Types of Ichthyosis
Some types only cause dry and scaly skin. Others cause problems inside the body, too.
Ichthyosis has lots of types—more than 30. Most forms of the disease are very rare. They can go along with other conditions or syndromes.
Some types include:
- Ichthyosis vulgaris. It's mild and affects about one out of every 250 people. Gray, brown, or white scales can show up usually in infancy. Most people with ichthyosis have this type.
- X-linked recessive ichthyosis. It affects about one out of 6,000 people, usually males. It starts at about 3-6 months and gets worse over time. You'll usually see scaling on the neck, face, trunk, and legs.
- Harlequin ichthyosis. You'll usually see this in newborns. It causes thick scaly plates all over the skin. It can change the way a newborn's face looks and can make it hard to move their joints.
- Epidermolytic ichthyosis. This type also happens in new babies. Infants with this type have fragile, blistered skin all over their bodies. Later, the blisters go away, and the skin gets scaly.
- Lamellar ichthyosis. Newborns with this have a clear membrane (collodion membrane) all over their bodies. After a few weeks, this covering peels away, leaving big, dark, plate-like scales.
- Congenital ichthyosiform erythroderma. This type is there at birth, too. Babies with this may also have a collodion membrane.
- Erythrokeratodermia variabilis. This type shows up in babies after a few months and can get worse or spread as they grow. Your skin may look rough, thick, or red, especially on the face, butt, arms, and legs.
- Progressive symmetric erythrokeratoderma. This type can start later in childhood compared with other types. You'll see dry, red, scaly skin, especially on the arms, legs, butt, face, ankles, and wrists.
Ichthyosis can be genetic (or inherited). It also can be acquired, meaning it happens later because of another illness or from medicine you're taking.
Inherited ichthyosisis a genetic condition. That means it's passed down to you from your parents. Sometimes, parents who don't have ichthyosis can still pass it down. Genes are the codes that tell your body to make proteins, which determine how your body looks and functions. When there are changes or mutations in a gene, it can cause disease. Ichthyosis gene mutations affect the proteins that protect your skin and keep it moist. They also affect how quickly your body gets rid of or grows new skin cells.
Ichthyosis usually shows up in infancy or early childhood. If both of your parents have a mutation that can cause it, you're likely to have a more serious condition than if only one of them has it. Sometimes, ichthyosis is genetic without being inherited. This can happen when a new mutation comes up in a developing fetus. In this case, the baby won't have enough of a protein (filaggrin) they need for their outer skin layer. They also won't shed dead skin cells the way they should.
Acquired ichthyosis shows up in adulthood. Doctors don't know why it happens, but people with it often have other conditions, including:
- Underactive thyroid gland
- Kidney disease
- Sarcoidosis, a rare disease that causes patches of inflammation inside the body
- Cancer such as Hodgkin's lymphoma
- HIV infection
Some medicines might also trigger the condition, but it's rare. These include:
Your symptoms will depend on what type of ichthyosis it is. But 95% of people with it have ichthyosis vulgaris. It's possible to have ichthyosis and not even know it. You might just think you have dry skin.
Dry, scaly skin is the main symptom. The scales form on only some parts of the body, such as the:
- Face and scalp
The scales can be white, gray, or dark brown. They might have thick or thin cracks running through them. Dryness and scaling get worse in cold, dry weather. They usually improve in warmer weather.
Other signs of ichthyosis vulgaris, the most common type, include:
- Itchy, dry skin
- Skin that's thick or rough and may look dirty, especially on the palms of your hands and soles of your feet
- White, gray, or brown scales
- Extra lines on the hands and feet that may be deep or even crack
- Rough and bumpy skin on the arms, thighs, and butt that may look like acne (keratosis pilaris)
- Trouble sweating
Other, more severe signs of ichthyosis are:
- Skin redness
- Blisters that can break to cause wounds
- Lines on the palms of the hands and soles of the feet
- Tight skin that makes it hard to move
- Hair loss or hair that breaks easily
- Dry eyes that are hard to close
- Trouble hearing
- Trouble bending your joints
Many people with ichthyosis also have eczema, a red, itchy rash. Ichthyosis usually shows up in babies or young kids before age 5. Symptoms may get worse until a child reaches puberty. Sometimes, it can get better with age. Your symptoms will depend on how severe your disease is and what's causing it. It usually doesn't go away, and you may need treatment to help with symptoms all your life.
Skin is your body's barrier. It holds moisture inside and keeps out bacteria and other invaders that might make you sick. When ichthyosis makes pieces of your skin scale off, you lose some of this protective layer.
Scaling can lead to complications such as:
- Skin infections
- Blocked sweat glands, which can lead to overheating
- Slow hair growth from scales on the scalp or hair loss
- Burning more calories because the skin has to work harder to turn over cells
Ichthyosis can cause emotional issues, too. The scales can affect the way you look. People with this condition sometimes feel depressed and have low self-esteem.
Kids with ichthyosis are more likely to get:
- Hay fever
Men with ichthyosis are also at an increased risk of:
Other complications include:
It can't be cured, but treatments can help you manage dry and scaly skin.
Rub cream, lotion, or ointment onto your skin every day to add moisture. Look for rich creams that have any of these ingredients: lanolin, alpha hydroxy acids, urea, or propylene glycol. Products with ceramides or cholesterol also keep skin moist.
Apply the lotion right after you step out of the shower or bath, while your skin is still damp. This will help hold in moisture.
Other things you can try:
- Take more than one bath a day to hydrate your skin.
- Take baths in salt water to help with burning, stinging, or itching.
- If you get infections often, try adding a little bit of bleach to your baths.
- Rub your skin with a pumice stone or rough sponge to help get rid of dead skin.
- Remove dead skin with a product that contains salicylic acid, glycolic acid, or lactic acid.
If the dryness and scaling are severe, your doctor might prescribe an oral retinoid medicine such as acitretin (Soriatane) or isotretinoin (Absorica, Claravis, Sotret, and others). Retinoids can cause side effects such as weakened bones, dry mouth, and upset stomach. You might need antibiotics for skin infections. If your skin condition is caused by another condition or medicine you're taking, treating the disease or changing the dose may help.
Ichthyosis isn't life-threatening, but it can be life-changing. Your dermatologist can recommend treatments to help your skin look and feel better. If you feel depressed or have low self-esteem, talk to a therapist or other mental health experts.
You can't make ichthyosis go away. But there's a lot you can do to make it feel better and help with your symptoms. Some steps you can take include:
- Taking baths or other steps to add moisture to your skin.
- Staying cool. Heat and sweat can make it worse.
- Use a humidifier to keep heat and air conditioning from drying out your skin.
- Wear loose clothes that are cotton or another fabric that doesn't bother your skin.
- Avoid laundry detergents or other products with dyes and perfumes.
It always helps to find other people with the same condition. They can be a source of support and have ideas for things to try. Look for a support group online or where you live with other people who have ichthyosis. If you're struggling with your skin condition, reach out to a mental health professional.