8 Symptoms of Crohn’s Disease That Don’t Affect Digestion

Crohn’s disease can cause symptoms that go beyond digestive problems, including skin conditions, osteoporosis, and even arthritis.

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Crohn's disease can cause arthritis and migraine, among other conditions.Olga Rolenko/Getty Images; Getty Images; Canva

Gas, bloating, diarrhea, nausea: You’re probably all too familiar with these common Crohn’s disease symptoms, especially if they strike on a regular basis. Yet, because Crohn’s disease is a systemic (whole body) condition, its symptoms could extend beyond your digestive system.

“Crohn’s disease is a body-wide disease that is caused by excessive inflammation,” says Nirmal Kaur, MD, director of the inflammatory bowel disease center at Henry Ford Health System in Detroit. “Some people with Crohn’s disease only have inflammation in the bowel, but about 30 to 40 percent of people have what are called extraintestinal manifestations, or Crohn’s disease symptoms outside of their gastrointestinal tract [or digestive organs].”

In most cases, the primary treatment for non-digestive symptoms of Crohn’s is the same as for bowel-related symptoms — medications, such as aminosalicylates (for mild cases), immunosuppressive agents, biologic therapies, and corticosteroids. For most people, they work well for all Crohn’s symptoms. “Most people notice that when their digestive Crohn’s disease symptoms are treated, their non-digestive symptoms get better as well,” says Dr. Kaur.

Understanding Non-Digestive Symptoms of Crohn’s Disease

Here are eight symptoms of Crohn’s disease that show up outside of the digestive tract, why they occur, and how they can best be managed.

Arthritis

Because of the inflammation associated with the disease, up to 30 percent of people with Crohn’s also develop arthritis, according to the Crohn’s & Colitis Foundation. “This arthritis risk is highest in the larger joints, such as the knees, elbows, and wrists, which is called peripheral arthritis,” Kaur says. “But arthritis can show up anywhere in people with Crohn’s disease.” Usually, if the Crohn’s is treated, the arthritis improves as well, the Foundation says.

Osteoporosis

“People with Crohn’s disease are at higher risk for osteoporosis than the general population is,” says Mariam Fayek, MD, an attending physician at Women & Infants Hospital Center for Women’s Gastrointestinal Health in Providence, Rhode Island. “The chronic inflammation of Crohn’s disease leads to increased bone loss, and people with Crohn’s are also more likely to be vitamin D deficient, both of which contribute to osteoporosis risk.”

This vitamin D deficiency occurs partly because the portion of the bowel that absorbs vitamin D is diseased.

People who’ve taken steroids for Crohn’s disease may also be more likely to develop osteoporosis, since the medication can thin the bones. “Prior to the 1990s, there weren’t many therapies for Crohn’s disease outside of prednisone, so many people with Crohn’s disease who are older in age received a lot of this drug and now have osteoporosis,” Kaur says.

To reduce the risk for osteoporosis:

  • Avoid prolonged use of prednisone as much as possible
  • Perform weight-bearing exercises regularly
  • Avoid smoking
  • Minimize alcohol and caffeine intake
  • Eat a healthy, balanced diet

“You should also get your vitamin D levels checked and have regular bone density tests,” Dr. Fayek says.

Skin conditions

Crohn’s disease can cause skin conditions such as erythema nodosum — characterized by tender red nodules on the legs and shins — and pyoderma gangrenosum — large, painful ulcers that occur mostly on the legs.

“These skin conditions are caused by the inflammatory process of Crohn’s disease, and the treatment for them is to treat the Crohn’s disease, sometimes along with topical therapy by a dermatologist,” Kaur says. Another possible skin condition that can occur alongside Crohn’s disease is psoriasis. Although psoriasis appears to be a skin disease, because it produces discolored patches of skin, it’s actually an inflammatory disease. It’s also linked to arthritis and Crohn’s disease by way of psoriatic arthritis, an inflammatory joint disease that can cause bone and joint damage.

Fatigue

“People with Crohn’s disease can become anemic and experience fatigue because of blood loss and inflammation,” Fayek says. “Fatigue can also be associated with depression, which is common in people with chronic conditions such as Crohn’s disease.”

Vitamin D deficiency can also contribute to fatigue, as can the body-wide inflammation that goes along with Crohn’s disease. “Taking vitamin D and iron supplements and effectively treating Crohn’s disease can all help to ease fatigue,” Kaur says.

Canker sores

While mouth sores aren’t a common symptom of Crohn’s disease, Crohn’s inflammation can involve any part of the gastrointestinal tract, from the mouth to the rectum. “Severe oral involvement may present with aphthous ulcers [canker sores] or pain in the mouth and gums,” Fayek says. These painful mouth sores usually occur during Crohn’s flares and appear on the gums or the underside of the tongue. In addition to regular Crohn’s treatment, oral pain-relief rinses and gels, an oral antibiotic rinse, or corticosteroids may help.

Fever and infection

“Fever can be a symptom of Crohn’s disease because of the inflammation associated with the disease,” Fayek says. Some people with severe Crohn’s disease can get a fever if they develop an abdominal abscess, which is a pocket of pus that extends through the wall of the intestine to the abdominal cavity, Fayek explains.

Fever can also be a sign of infection. And people who take certain medications, including biologics, which suppress the immune system, can have an increased risk for infections. “Patients on immunosuppressive medications are particularly at risk for certain fungal infections and reactivation of tuberculosis,” she says. If you have a fever over 100.5 degrees Fahrenheit, she says, you should contact your gastroenterologist right away. If the source of the fever is an infection, you’ll likely be treated with antibiotics.

It’s important for people on immunosuppressive therapy to stay up to date on vaccinations, Fayek says, but live, weakened virus vaccines need to be avoided. These inactivated vaccines can and should be used instead:

  • A yearly flu vaccine
  • Certain pneumonia vaccines; talk to your doctor about which ones you should get if you’re starting immunosuppressive therapy.
  • Tdap (tetanus, diphtheria, and pertussis), which should be given as a booster, particularly if it’s been more than 10 years since your last vaccine.

Other inactivated vaccines include hepatitis A, Haemophilus influenzae type B (Hib), meningococcal, and HPV, Fayek says. Your doctor can help you determine what kind of vaccination schedule you should follow.

Migraine attacks

Some people with Crohn’s disease or ulcerative colitis can get migraine attacks, which are thought to be rooted in inflammation. Once people take medications for other symptoms of Crohn’s disease, migraine usually also improves, Kaur says.

Eye infections

“There are two types of eye conditions that can occur in people with Crohn’s disease, and both are emergencies,” Kaur says. The first is episcleritis, which is irritation and inflammation of the episclera, a thin layer of tissue that covers the white part of the eye. “Episcleritis is extremely painful, and it makes the eye very red,” she says.

The second is uveitis, which is inflammation of the uvea — the middle layer of the eye. “Uveitis causes distinct pain,” Kaur says. Sudden redness, blurred vision, and light sensitivity are other possible symptoms, according to the American Academy of Ophthalmology. “Both eye conditions are rare, but if you have Crohn’s disease and experience any eye pain or redness, call your doctor or head to the emergency room right away.”

A review in the journal Gastroenterology says that uveitis associated with Crohn’s should be treated as a separate issue and will not improve with Crohn’s medication alone, but episcleritis will respond to Crohn’s treatment.

Like the digestive symptoms of Crohn’s disease, these non-digestive symptoms are more likely to crop up during a flare or if your Crohn’s is severe. If you have Crohn’s disease and experience any of these symptoms, talk to your doctor promptly to get the care you need.