Is That Rash Psoriasis, or Is It Something Else?
From white blisters to red and scaly patches, psoriasis skin rashes come in several different forms. How do you know if you have psoriasis or a similar-looking skin condition?
Psoriasis can resemble other irritating skin conditions.
Psoriasis?is an autoimmune disease thought to be caused by an immune system dysfunction. If you have psoriasis, your immune system sends signals to your skin that speed up the production of skin cells. While there are signs and symptoms that set the disease apart from other conditions affecting the skin, it isn’t always easy to distinguish it at first.
About 7.5 million people in the United States have?psoriasis, which causes itchy, scaly patches of thick, red, dry skin called plaques. Psoriasis plaques can consist of a few spots of dandruff-like scales or major eruptions that cover large areas. While the disease can affect any part of your body, it most often surfaces on the scalp, elbows, knees, back, face, palms, and feet.
There are five types of psoriasis — plaque psoriasis,?guttate psoriasis, pustular?psoriasis, inverse psoriasis, and erythrodermic psoriasis — none of which is contagious. Each type causes a different?skin rash?and can appear on different areas of the body. Plaque psoriasis, also known as psoriasis vulgaris, is the most common type. As many as 90 percent of people with psoriasis have this form. Guttate psoriasis is the second most common type. Far less common is pustular psoriasis, which is characterized by pus-filled bumps known as pustules, and erythrodermic psoriasis, a very serious form of the disease that affects about 3 percent of people with psoriasis.
It’s unclear what exactly causes psoriasis, though?genetic factors?have a lot to do with whether you’ll develop the chronic skin condition.
Psoriasis symptoms typically respond to treatment. Most psoriasis therapies aim to stop skin cells from growing so quickly and to smooth out the skin. But the disease may never go away completely, and it tends to come back.?Treatment options?can include?topical corticosteroids and biologic drugs. Another option is light therapy, or phototherapy, in which targeted light rays are delivered to the skin.
Because psoriasis can look like other skin conditions that cause scaly patches and itchy rashes with inflammation, it is often confused with various disorders. These may include common skin conditions such as acne, eczema, or heat rash. Psoriasis can also resemble?and be confused with the fungal infection known as ringworm.
Most of the time, psoriasis can be diagnosed with a physical examination. However, a skin biopsy may be needed to rule out other possibilities and arrive at a definitive diagnosis.
Do you know how to spot psoriasis symptoms? Here are some things you can look out for.
(The images that follow are of real medical conditions and may, in some cases, be graphic.)
Plaque Psoriasis: Red Bumps and Silvery Scales
Plaque psoriasis?is the most common form of the chronic?skin condition, affecting about 80 percent of people with psoriasis. Usually starting as small red bumps on the skin, plaque psoriasis (pictured) develops into red patches with a silvery, scaly coating — these raised patches are called plaques. Plaques usually show up on elbows, knees, and the lower back, and they can last for months or even years without treatment.
Guttate Psoriasis: Small Red Spots
Guttate psoriasis?(pictured) — the second most common type of psoriasis — is characterized by multiple small, round red spots on the skin, usually widespread across the trunk and limbs. Often resulting from a bacterial or viral infection?in children, such as strep throat, these spots come on suddenly and sometimes require oral medication or injections. Mild cases, however, may clear up without treatment.
Seborrheic Dermatitis: Itchy, Scaly Patches
A psoriasis skin rash tends to itch, burn, and feel sore. Patches of psoriasis commonly occur on your knees and elbows. Many people also have scalp psoriasis. The common skin rash seborrheic dermatitis (pictured) also causes scaly, itchy skin patches. It can occur on your scalp, where it may be called dandruff, or on your face and chest. While doctors don't know the exact cause of seborrhea, it occurs across the age spectrum, in babies as well as in adults, and is usually treated with creams and lotions.
Pityriasis Rosea: Cold-Like Symptoms
Pityriasis rosea (pictured) causes a red skin rash that is scaly and can look like guttate psoriasis. This skin rash is common in children and young adults. It often begins with?cold-like symptoms?and is followed by red, scaly, and sometimes?itchy?oval-shaped patches that appear on your back or abdomen. Like psoriasis, this skin rash is not contagious. Doctors do not know the exact cause, but pityriasis rosea may be due to a viral or bacterial infection. You can take medication to relieve the itching, and the rash should go away after a few weeks to months. And unlike psoriasis, this skin rash rarely comes back.
Eczema: Red, Itchy, Irritated Skin
Like psoriasis,?eczema?(pictured) is a chronic skin condition that often causes intense itching. Scratching causes redness and inflammation of the skin, leading to a worsening of the eczema. Scratching can also cause a secondary bacterial infection. The most common type of eczema is caused by a reaction to irritants like detergents, soaps, or household cleansers. So if you have eczema, you should be careful to use mild soap and regularly moisturize your sensitive skin. Your doctor may prescribe a steroid cream or other medications if eczema is severe.
Acne: Blocked Pores That Lead to Pimples
Some forms of psoriasis appear as pus-filled blisters that may be confused with pimples. Pustular psoriasis forms white blisters that are filled with pus and surrounded by red skin. Far more common than psoriasis,?acne?(pictured) also causes a pus-filled?pimple?eruption. However — unlike psoriasis — acne is caused by excess oil, blocked pores, and bacteria. Acne is common in teens and young adults and occurs on the face, neck, back, or chest. Pustular psoriasis is usually seen in adults and can occur anywhere on the body, but less likely on the face.
RELATED: 7 Easy Home Remedies for Acne
Measles: A Facial Rash That Can Cover the Body
Like guttate psoriasis,?measles?(pictured) also follow symptoms of an upper respiratory infection in children and cause a skin rash of small, red spots. However, the measles skin rash usually starts on the face and spreads down to cover the body and is accompanied by fever, cough, and a runny nose. Measles rash is also flat, while the rash of psoriasis is typically raised. Measles is caused by a virus and is contagious, though the measles vaccination has made this a rare disease in the United States.
Shingles: A Rash and Severe Pain That Lingers
Shingles?(pictured) is another viral infection that shares some symptoms with psoriasis. Like psoriasis, shingles can make your skin burn and itch and produces a red, blistered skin rash. Shingles is caused by the same virus that first brings on?chickenpox. The virus stays in your body and can come back years later to cause shingles, especially during times of stress or infection. The skin rash of shingles follows the course of a single nerve, usually on the trunk. In some cases, severe pain lasts long after the burning, itchy rash disappears. Shingles is more common in people over age 50.
Ringworm: Fungal Infections of the Skin and Nails
Tinea is a type of fungal infection that resembles some symptoms of psoriasis. Psoriasis can cause the thick fingernails symptomatic of fungal nail infections, and both can cause red, itchy skin rashes. When tinea grows on your skin, it can cause a scaly, red skin rash that clears in the middle, called?ringworm?(pictured). Fungal infections of the skin and nails can be hard to treat. Antifungal medications work, but you may need to take them for a long time.
Heat Rash: Sweating That Leads to Bumpy, Red Skin
Inverse psoriasis?is a type of psoriasis that forms in the armpits and skin folds under breasts or in groin areas, making the skin red and shiny.?Sweating?makes this type of psoriasis worse. Heat rash (pictured) also makes your skin red and forms in skin folds of the groin, breasts, and armpits. Heat rash occurs in hot, humid conditions. Sweating can cause your pores to get blocked and result in a bumpy, red skin rash that stings. Heat rash is more common in newborns, but can also affect older children and adults.
Dry, Cracked Skin: Irritation That Can Lead to Infection
Dry, cracked skin is a psoriasis symptom. However, dry air can also cause your skin to become?dry and itchy. When the skin is dry and irritated (pictured), it's more likely to get infected. Infection may cause your skin to become red and swollen. If you have any skin rashes that keep coming back or won't go away, see your doctor. Most cases of psoriasis can be diagnosed with a physical examination; but because psoriasis can look like many other skin conditions, a?skin biopsy may have to be done to definitively diagnose it.