Keratitis and Thyroid Eye Disease

Keratitis can impact people with the autoimmune condition known as thyroid eye disease (TED). Both diseases involve inflammation. In keratitis, the cornea (the see-through layer on top of the iris and pupil) becomes inflamed. In TED, tissues around the eyes become inflamed.^1,2

Some conditions and drugs can raise a person’s chance of having keratitis. These include immune disorders and steroids that decrease the body’s power to fight infections. Eye injury and wearing contact lenses can also increase the risk of keratitis.^1,3,4

Keratitis and thyroid eye disease can but do not always overlap. Research does show a higher rate of keratitis among people with TED. A 10-year study published in 2019 found microbial keratitis in 13 out of 1,000 people with TED. In this study, most of those with keratitis were men with active TED.^5,6

Types of keratitis and diagnosis

There are 2 distinct types of keratitis:^1,4

• Microbial (infectious) – This type is caused by germs such as bacteria, fungi, parasites, and viruses
• Noninfectious – This type often stems from a wound to the eye

An eye doctor can confirm the presence of keratitis. They will look at your eyes during an exam. The doctor uses special tools such as a penlight and slit lamp to better see the presence and effects of keratitis. A lab test can help pinpoint which, if any, germs exist in cells or tears.⁷

Symptoms of keratitis and TED

Common symptoms of keratitis include:^1,3,6

• Being bothered by bright light
• Blurry vision
• Burning, pain, and redness in the eyes
• Decline in eyesight
• Feeling of a fragment in the eye
• Inflammation
• Loss of vision
• Lots of tears or discharge from the eyes

People with TED may experience some of the same symptoms of keratitis, such as:²

• Blurry vision
• Discomfort in the eyes
• Inflammation
• Loss of vision
• Pain and redness in the eyes
• Problems with bright lights
• Watery eyes

A distinct symptom of TED is eyelid retraction. This is when the eyelid pulls back or retracts, making it hard or even impossible to blink or fully close the eyes. This can make infection or injury more likely. Severe eyelid retraction occurred in 92 percent of those with keratitis and TED in the 2019 study.^2,5,6

Treatment for keratitis

Receiving treatment for keratitis as early as possible is ideal. This may help keep keratitis from getting worse and prevent vision loss.^1,3,4

Common treatments for keratitis include eye drops, oral drugs, and topical steroids. Which treatment each person should take depends on the cause of the keratitis. For instance, antibiotic drops tackle the bacteria that causes some cases of keratitis. If lab tests show fungi in the eyes, treatment includes antifungal drugs.^6,7

Severe keratitis may require surgery. This could be removing some of the tissue on the white part of the eyes and inside the eyelids. A cornea transplant may be needed if the cornea becomes extremely damaged.^4,6,7

What can I do about keratitis?

You can do something about keratitis, whether you have thyroid eye disease or not. Take good care of your eyes. Protect your eyes from injury while playing sports and working. If you use contact lenses, follow all instructions for cleaning and wearing them.¹

Watch your symptoms closely. Take note of new symptoms, as well as existing ones that get worse. Think about any changes in your health or routine that may have impacted your symptoms. These could be getting dirty water in your eyes or taking a new drug that impacts immune function.¹

If you notice signs of keratitis, see an eye doctor as soon as you can. They can check your eyes and diagnose the problem. An eye doctor can also order tests, prescribe drugs, and advise on all treatment options.