Ulcerative Colitis Rash Signs and Symptoms

Ulcerative colitis is an inflammatory bowel disease (IBD) that causes inflammation and ulcers (sores) in the innermost lining of the colon and rectum.

It can also affect other parts of your body, most commonly your skin. Up to 35% of people with ulcerative colitis have a skin condition.

Ulcerative colitis can cause many skin changes, including a variety of skin rashes.

If you have ulcerative colitis and develop a new rash, it may be due to your ulcerative colitis. Here are some skin rashes you may develop if you have ulcerative colitis, including what they look like, how they develop, and how to treat them:

Erythema Nodosum

Erythema nodosum is a skin condition with a name that translates to “red bumps.” About 2-10% of people with IBD develop erythema nodosum, with women affected more often than men.

Appearance: Erythema nodosum can appear as small, round nodules (lumps) or plaques (raised patches) that are red, firm, and painful to touch. They most commonly form on your shins and ankles but may also appear on your arms. Some people also experience joint and muscle pain.

Development: The rash typically appears when you have a flare (a period when disease symptoms are present), but it can also occur just before a flare.

Treatment: Treatment involves managing your IBD, though healthcare providers will sometimes prescribe steroids or antibiotics.

Pyoderma Gangrenosum

Pyoderma gangrenosum is an inflammatory condition that can cause skin ulcers. It is more common in people with ulcerative colitis than in those with Crohn’s disease; ulcerative colitis is associated with 5-12% of pyoderma gangrenosum cases.

Appearance: The condition starts as small, extremely painful blisters on your shins (and sometimes your arms). The blisters can join together and grow into deep, chronic ulcers.

Development: It’s unclear whether the development of pyoderma gangrenosum is associated with ulcerative colitis flares or severity.

Treatment: Pyoderma gangrenosum sometimes heals when your IBD is controlled. Other times, the lesions break down or form deep ulcers that require a wound care professional and more extensive treatment, such as antibiotics and topical (applied to the skin) ointments.

Bowel-Associated Dermatosis-Arthritis Syndrome (BADAS)

Bowel-associated dermatosis-arthritis syndrome (BADAS) is a rare condition that includes flu-like symptoms, arthritis, and skin lesions.

Appearance: The lesions can appear as small, raised bumps, pus-filled bumps, or plaques on the arms or torso. They don’t always cause symptoms, but they can be painful or itchy and red.

Development: Healthcare providers initially thought BADAS was related to bowel bypass surgery. Scientists now believe gastrointestinal conditions like ulcerative colitis and bacterial overgrowth may be responsible.

Treatment: You may need antibiotics, steroids, and biologics.

Sweet Syndrome

This rare condition occurs alongside several inflammatory and autoimmune diseases, including ulcerative colitis. It primarily affects women. In addition to a rash, you can develop fever, headache, and joint pain.

Appearance: Sweet syndrome can cause tender, red plaques or nodules on the upper body.

Development: Sweet syndrome comes on suddenly.

Treatment: It is usually treated with steroids or anti-tumor necrosis factor (TNF) agents.

Acrodermatitis Enteropathica

Acrodermatitis enteropathica is caused by nutritional deficiencies. Because healthcare providers focus on proper nutrition in IBD as a way to prevent complications, the condition is not as common as it once was.

Appearance: The flaky rash typically occurs on your face, hands, feet, and perineum (the skin between your anus and genitals).

Development: You can develop acrodermatitis enteropathica if you lose too much zinc due to chronic diarrhea.

Treatment: You will likely need zinc supplements, sometimes supplied directly to the intestines. Compresses and moisturizers may help soothe your skin.

Pyoderma Vegetans

Pyoderma vegetans can affect people with ulcerative colitis.

Appearance: This condition presents as blisters, plaques, or patches around your groin and under your arms. As these rashes heal, they tend to get darker.

Development: It’s believed that pyoderma vegetans occurs because of an immune system abnormality.

Treatment: Typically, the treatments used to address IBD will help clear this skin condition.

When you have an ulcerative colitis flare, the inflammation that causes digestive symptoms can also affect your skin. Your skin is one of the most common areas where the inflammation will be apparent, even though ulcerative colitis can affect any part of your body, including your eyes, lungs, kidneys, and cardiovascular system.

Healthcare providers are unsure exactly what causes ulcerative colitis symptoms like skin rashes. Experts suspect your genes, environment, microbiome, and an overactive immune system may play roles.

Having ulcerative colitis can impact your skin in other ways. Here are a few skin changes besides a rash you may experience if you have IBD:

• Psoriasis: Ulcerative colitis and psoriasis are chronic inflammatory conditions that often exist together. People with psoriasis are nearly twice as likely as the general population to develop ulcerative colitis.
• Vitiligo: This chronic inflammatory skin condition, which causes a loss of pigmentation (color), can occur in people with ulcerative colitis.
• Anal fissures: Fissures are small tears in the lining of your anus that can crack and bleed, causing pain and itchiness. Warm baths or topical ointments can help relieve discomfort.
• Acne: While ulcerative colitis does not cause acne, medications like steroids used to treat the condition can increase the risk of acne breakouts.
• Skin cancer: People taking immunosuppressive medications for their IBD may have a higher risk of skin cancer than the general population. Make sure you wear sunscreen to reduce your risk.
• Vasculitis: This condition occurs when your blood vessels become inflamed. It can cause raised red areas on the skin. Once IBD is treated, vasculitis may resolve. 

Treating your ulcerative colitis and any accompanying skin conditions may require a multipronged approach.

In some cases, treating your IBD will resolve the skin issues. Once your ulcerative colitis improves, so can your skin condition. Because there is no cure for ulcerative colitis, the goal is often to reduce inflammation and put your symptoms in remission.

Other times, your skin conditions will need to be treated separately. The exact treatment you need will depend on the condition. Treatments vary widely, from medications to surgery.

If your medications are causing skin issues, your healthcare provider may make changes to help alleviate your symptoms.

If you have skin rashes or other skin concerns that are difficult to explain or identify, you should see a healthcare provider, such as a dermatologist (a doctor who specializes in skin conditions).

You should especially see a healthcare provider if you have a rash that:

• Covers most of your body
• Has blistered or turned into open sores or raw skin
• Is accompanied by a fever
• Spreads quickly
• Is painful
• Affects your eyes, lips, mouth, or genitals

The provider can identify the skin condition and help determine whether it’s associated with your ulcerative colitis.

These skin manifestations sometimes occur before an ulcerative colitis flare; other times, they appear when the inflammation in your gastrointestinal tract is extensive. An accurate diagnosis of your skin rash can help you get any necessary treatment for the inflammation in your digestive tract.

Nearly half of the people who have ulcerative colitis will experience symptoms outside their digestive tract, with skin rashes being common.

Erythema nodosum and pyoderma gangrenosum are common skin rashes associated with ulcerative colitis, but other rashes can occur.

Skin symptoms may occur before or during a flare. Managing ulcerative colitis often resolves the skin concern, but some conditions need additional treatments.