How Crohn’s Disease Affects the Eyes
When most people think of Crohn’s disease, they think of digestive problems. The inflammatory bowel disease (IBD) occurs when the body’s immune system attacks its own digestive tract, leading to symptoms such as abdominal pain and cramping, diarrhea, rectal bleeding, fatigue and more.
These symptoms tend to occur in occasional “flare-ups” that last a few weeks or more, followed by a period when Crohn’s disease is in remission. Over time, Crohn’s disease can cause chronic problems in the body, such as low energy, weight loss, malnutrition and damage to the digestive system in the form of fissures, abscesses and other problems.
Crohn’s disease and eye problems
Because Crohn’s disease impacts the digestive system, you might not think of it as a medical condition that can have a negative impact on your eyes. However, the Crohn’s & Colitis Foundation notes that about 10 percent of people who have an inflammatory bowel disease like Crohn’s disease also have complications related to the eyes.
Though it may seem strange that a primarily digestive disorder would cause eye problems, a 2017 review article in the World Journal of Gastroenterology noted that the common link here is inflammation. Just as inflammation causes problems in the digestive tract, it can also cause it in the eyes. Other issues with the eyes may be related to the malnutrition that can sometimes occur with Crohn’s disease.
The same journal article noted that eye problems tend to be more common with Crohn’s disease than with other inflammatory bowel diseases, such as ulcerative colitis. And though they do exist, most of these eye problems are minor, treatable and do not affect vision, although some complications can occur in rare instances.
Here’s what you need to know about the various eye problems that may occur along with Crohn’s disease.
Episcleritis
The outer coating of the white part of the eye is medically known as the episclera. When the blood vessels in the episclera become inflamed, this may lead to episcleritis, which is a common eye problem among people with Crohn’s disease.
- Symptoms
Eye redness, moderate discomfort and mild tenderness are all potential symptoms of episcleritis. Some people describe the feeling that accompanies episcleritis as a burning sensation. - Treatment
Eye drops, either over-the-counter or prescription corticosteroid drops, are the typical treatment for episcleritis. A topical or oral non-steroidal anti-inflammatory drug (NSAID) may also be recommended to ease the symptoms of episcleritis.
Uveitis
While the outer coating of the white part of your eye is known as the episclera, the middle layer of the eye is known as the uvea. Inflammation in this layer of the eye is known as uveitis, and it is one of the most common eye-related complications that can occur with Crohn’s disease and other inflammatory bowel diseases.
- Symptoms
Eye redness, pain, blurred vision and sensitivity to light are all characteristic signs and symptoms of uveitis. In some cases, uveitis develops gradually, while other cases come on quite suddenly. Uveitis that is not treated may eventually develop into glaucoma. - Treatment
The primary treatment for uveitis is prescription corticosteroid eye drops. If those are unsuccessful, corticosteroid pills or injections, antibiotics or immunosuppressive drugs may be recommended. The Crohn’s & Colitis Foundation notes that bringing Crohn’s disease symptoms under control can also help with the management of uveitis.
Keratopathy
The cornea is the clear, circular membrane at the front of the eye that is responsible for focusing light into the eye. When an abnormality develops in the cornea, one potential cause is an eye condition known as keratopathy. In the case of Crohn’s disease, the development of keratopathy may be due to inflammation of the eye.
- Symptoms
Typically, keratopathy related to Crohn’s disease does not cause any pain, loss of vision or other concerning symptoms. Your ophthalmologist or optometrist may detect its presence during an eye examination due to the appearance of small white deposits around the edge of the cornea. - Treatment
In most cases, no treatment is needed for keratopathy related to Crohn’s disease. However, if you have been diagnosed with both Crohn’s disease and keratopathy, be sure to contact your doctor if any concerning symptoms related to your vision develop.
Dry eyes
As Crohn’s disease progresses, certain vitamin deficiencies and other causes of malnutrition can occur. One potential complication of these deficiencies is dry eye, which can result from a deficiency of vitamin A.
- Symptoms
When dry eye occurs, it may be accompanied by a gritty or sandy feeling in your eyes. Tear production can decrease, which removes the eyes’ natural source of lubrication. Over time, your eyes can become increasingly itchy and painful. They are also more susceptible to developing an infection. Night blindness can also occur. - Treatment
Mild cases of dry eye can be treated with eye drops, while more severe situations may call for vitamin A supplementation or injections. If an infection occurs as a result of dry eyes, then antibiotics may be necessary.
Glaucoma
Occasionally, the mild eye problems that can result from Crohn’s disease can turn into bigger problems if they're left untreated or are treated improperly. One such instance of this is glaucoma, a condition that causes damage to the optic nerve due to high pressure in the eye. In the case of Crohn’s disease, it can develop due to a case of uveitis that goes untreated, or it can also occur after long-term use of corticosteroids to treat other eye problems.
- Symptoms
Glaucoma is one of the leading causes of vision loss or blindness in people older than 60. Eye pain, eye redness, blurred vision, tunnel vision, seeing a halo around lights, headache, nausea and vomiting are all potential symptoms that might be a sign of glaucoma. - Treatment
The damage caused by glaucoma cannot be reversed, so your best bet is to catch it early and attempt to slow down the damage before it gets worse. Prescription eye drops, oral medications and surgery are all potential treatment options for glaucoma.
Cataracts
Much like glaucoma, cataracts are a complication that can develop if other eye problems are left untreated, or if certain medications (such as corticosteroids) are used for too long. Cataracts cause a gradual cloudiness in the lenses of the eye, which can greatly affect your vision over time.
- Symptoms
Potential symptoms of cataracts include fading or yellowing colors, double vision, seeing a halo around lights, light and glare sensitivity, difficulty seeing at night and, of course, blurred, cloudy or dim vision. People with cataracts might find that they need brighter lights to do common activities, or that their vision prescription changes more frequently than they’d expect it to. - Treatment
Surgery is the only viable treatment option for removing cataracts. A cataract surgery involves removing the clouded lens from the eye and replacing it with an artificial lens. In people who cannot use an artificial lens, glasses or contact lenses can be used to correct vision once the cloudy lens is removed.
The bottom line
Though eye problems don’t affect everyone with Crohn’s disease, there’s no question that it’s a potential risk that people with Crohn’s need to be aware of. For that reason, it’s a good idea to see an ophthalmologist on a regular basis if you have Crohn’s. Even if you haven’t noticed any vision problems, outcomes are always better if problems are detected and treated early on.
Article references
- Signs and Symptoms of Crohn’s Disease, Crohn’s & Colitis Foundation, 2019. https://www.crohnscolitisfoundation.org/what-is-crohns-disease/symptoms
- Eye Complications in IBD, Crohn’s & Colitis Foundation, 2019. https://site.crohnscolitisfoundation.org/resources/eye-complications.html
- Ophthalmic manifestations in patients with inflammatory bowel disease: A review, World Journal of Gastroenterology, 2017. https://www.wjgnet.com/1007-9327/full/v23/i32/5836.htm
- Ocular Complications of IBD, Scientific World Journal, 2015.https://www.hindawi.com/journals/tswj/2015/438402/
- Episcleritis, The Ocular Immunology and Uveitis Foundation, 2017. https://uveitis.org/patient_articles/episcleritis/
- Uveitis, Mayo Clinic, 2019. https://www.mayoclinic.org/diseases-conditions/uveitis/diagnosis-treatment/drc-20378739
- Cornea, American Academy of Ophthalmology, 2016. https://www.aao.org/eye-health/anatomy/cornea-103
- Glaucoma, Mayo Clinic, 2019. https://www.mayoclinic.org/diseases-conditions/glaucoma/diagnosis-treatment/drc-20372846
- Cataracts, Mayo Clinic, 2019. https://www.mayoclinic.org/diseases-conditions/cataracts/diagnosis-treatment/drc-20353795