Up to 40 percent of people with an inflammatory bowel disease (IBD), including Crohn’s and ulcerative colitis, experience extraintestinal manifestations (EIMs): symptoms that occur outside the GI system. One study found that people with Crohn’s are more likely to have two or more EIMs than people with other forms of IBD. The causes of EIMs are unclear, says Feuerstein, but research suggests a genetic predisposition.
No matter the reason, EIMs can be a significant additional burden on those with IBD, and they can occur with inconsistent frequency depending on which organ is affected, before or after IBD is diagnosed. For those with Crohn’s disease, one research review found that the musculoskeletal system, skin, liver, gallbladder, bile ducts, and eyes were most likely to be affected.
The following are some common EIMs.
Arthritis
Inflammation of the joints is the most common EIM, affecting up to 30 percent of people with IBD. “Arthritis can affect the joints or the axial skeleton [the bones of the head and trunk],” Feuerstein says. Different types of arthritis may flare up along with disease activity or manifest independently of Crohn’s flares.
When arthritis develops with active disease, it typically gets better as intestinal symptoms improve. Chronic arthritis is more difficult to treat, says Feuerstein. “For immediate symptomatic relief, we always first recommend trying acetaminophen,” he says. People with IBD are typically told to avoid nonsteroidal anti-inflammatory drugs, or NSAIDs, due to the possibility of digestive upset. Biologic medications may be recommended for severe arthritis.
Skin Changes
Skin conditions can also be a complication of Crohn’s. Erythema nodosum is an EIM that causes raised, tender red bumps that usually appear on the shins and can affect up to 15 percent of people with Crohn’s. Pyoderma gangrenosum starts as a small bump or bumps on the skin and evolves into a large ulcer or ulcers that can grow and merge together, with raised borders, most often on the legs, though they can occur anywhere.
Liver Problems
A common complication of Crohn’s is metabolic dysfunction-associated steatotic liver disease (MASLD), formerly called nonalcoholic fatty liver disease, which rarely causes symptoms. Treatment of MASLD in people with Crohn’s is usually focused on improving diet and increasing physical activity.
A serious liver complication of Crohn’s is primary sclerosing cholangitis, which causes inflammation, scarring, and narrowing of the bile ducts. “While this is more common among people with ulcerative colitis, it can develop with Crohn’s disease as well,” says Feuerstein. “Typically, it’s a progressive EIM and may develop into cirrhosis and cholangiocarcinoma [cancer of the bile ducts].”
Also, the risk for gallstones is higher in those with Crohn’s disease than in people without the condition, according to research.
Eye Disorders
Most of the eye complications associated with Crohn’s are both treatable and unlikely to cause vision loss; they affect about 10 percent of people with IBD. Episcleritis, a condition that causes irritation and inflammation on the white of the eye, often goes away when Crohn’s symptoms begin to improve with treatment. Uveitis causes inflammation and pain in the middle layer of the eye — as well as blurred vision and light sensitivity — and may come on gradually or suddenly.
“Early recognition and treatment of uveitis is important,” says Feuerstein. If left untreated, the condition can become a medical emergency that may cause loss of vision.
Mouth Sores
Oral ulcers (canker sores) are most likely to occur during a flare and tend to subside when Crohn’s is under control. “For symptomatic relief, patients often use a lidocaine-based mouthwash,” says Feuerstein. “The lidocaine provides some numbing to alleviate the pain.”
Kidney Stones
These occur most often in Crohn’s with small bowel inflammation and in those who’ve had multiple small-bowel resections, says Feuerstein. Kidney stones usually cause sharp pain in the sides, lower back, or belly, as well as nausea, vomiting, and blood in the urine.
The calcium oxalate stones common in Crohn’s can be prevented with a limited-oxalate diet and adequate calcium. Oxalate is a chemical found mostly in plant foods, including spinach, beans, and nuts. Feuerstein says it’s important to drink lots of fluids, especially those that contain electrolytes.
Treatments for kidney stones vary depending on the severity of the symptoms. You’ll need to see a doctor and may need to consult with a nephrologist or urologist.
