Keratoconjunctivitis

What is Keratoconjunctivitis?

The conjunctiva is a clear, thin, moist layer that covers the sclera, the white part of our eyes. It starts from the border of the cornea, which is the outer clear layer of the eye, and covers both the white part of the eye (a region called the bulbar conjunctiva) and the inner side of the eyelids (known as the palpebral conjunctiva). Keratoconjunctivitis is an inflammation that involves the conjunctiva (also known as conjunctivitis) and the outer clear layer of the eye (known as keratitis). This inflammation can be caused by viruses, bacteria, autoimmune issues, toxic substances, and allergies. There are many possible causes for conjunctivitis and keratitis, but we are only going to focus on the more common causes of combined keratoconjunctivitis. Specifically, we’ll discuss four types: epidemic keratoconjunctivitis, vernal keratoconjunctivitis, superior limbic keratoconjunctivitis, and keratoconjunctivitis sicca.

What Causes Keratoconjunctivitis?

Keratoconjunctivitis is a health condition that can have many causes. It can be helpful to categorize these causes into two groups: infectious and non-infectious. Viral and bacterial infections are usually the most common reasons for this condition, with the majority of cases being a result of a viral infection. Non-infectious keratoconjunctivitis can be caused by allergies, exposure to harmful substances, or immune system problems. It is also useful to classify keratoconjunctivitis based on how quickly it develops and how long it lasts, such as whether it affects one or both eyes, begins in less than a week (hyperacute), starts within three to four weeks (acute), or lasts longer than four weeks (chronic).

Epidemic keratoconjunctivitis (EKC) is a form of this condition caused by a common virus known as the adenovirus. This virus, which can affect the eyes, breathing passages, digestive tract, and genital-urinary tract, is often responsible for widespread occurrences of EKC. This is especially true for types 8, 19, 37, and 54 of this virus.

Vernal Keratoconjunctivitis (VKC) is a severe form of allergic conjunctivitis. Although we don’t fully understand what causes it, the symptoms appear to be strongly linked to allergies, as this disease follows a pattern typically seen in an allergic reaction. It’s thought that a mix of immune system, genetic, and environmental factors (like air pollutants and allergens) likely contribute.

Superior limbic keratoconjunctivitis (SLK) is a long-term inflammation of the eye, but again, we aren’t exactly sure what causes it. One theory suggests that it might be due to constant friction within the eye, resulting in ongoing minor injuries.

Then there’s a form of keratoconjunctivitis known as dry eye syndrome or Keratoconjunctivitis sicca. This condition has been associated with various causes and often goes hand in hand with autoimmune disorders – conditions where the immune system mistakenly attacks healthy body parts. Regardless of the cause, the ultimate outcome is usually changes in the tear film that covers the eye’s surface and inflammation in the eyes, including the clear outer layer (cornea) and lining of the eyelids (conjunctiva).

Risk Factors and Frequency for Keratoconjunctivitis

Keratoconjunctivitis is a condition that varies a lot in how common it is, depending on things like the person’s age, their surroundings, and their genes. In the United States alone, around 6 million people visit healthcare providers each year due to symptoms of this condition.

• Allergies are the leading cause of keratoconjunctivitis, affecting up to 40% of people.
• A type of allergic keratoconjunctivitis (VKC) mainly affects school-aged kids, especially between 4 to 7 years old.
• Though VKC mainly affects young boys living in hot, dry places like West Africa, the Mediterranean, Middle East, India, and South America, it can also show up in kids as young as 5 months or adults in their 30s or 40s. It’s less common in North America and Western Europe.
• When it comes to infections, bacterial conjunctivitis is more common in children, causing around 50% of cases.
• Viral infections are the most common overall and can affect people of all ages. Adenoviruses cause as many as 90% of these viral infections.
• Keratoconjunctivitis sicca (dry eye) is a big public health issue in the U.S., affecting up to 17% of women and 11% of men.
• Many people might not even know they have keratoconjunctivitis sicca, as they tend to treat themselves without consulting a healthcare provider. This is an especially big issue for people with autoimmune conditions like Sjogren syndrome, rheumatoid arthritis, systemic lupus erythematosus, sarcoidosis, and scleroderma.
• Superior limbic keratoconjunctivitis is a rare type of the condition. It’s more common in women than in men by a ratio of about 3 to 1 and typically occurs in people between the ages of 20 and 60. This type is often associated with thyroid problems and keratoconjunctivitis sicca.

Signs and Symptoms of Keratoconjunctivitis

Keratoconjunctivitis is a condition that can cause itchy and irritated eyes, sensitivity to light, minor vision blurring, and excessive tearing. Several factors such as contact lens usage, exposure to sick individuals, chemical exposure, current use of eye drops or face creams, and recent activities that may have resulted in a foreign body or corneal abrasion can trigger this condition. Understanding the timeline of the symptoms, factors that worsen or improve the condition, and the patient’s medical history of systemic and autoimmune conditions, atopy, and thyroid disease is crucial for diagnosis.

Different types of keratoconjunctivitis have varying symptoms. Viral keratoconjunctivitis typically affects one eye first and then spreads to the other. Symptoms include discomfort or itchiness, light sensitivity, watery discharge, and inflammation of the conjunctiva. It’s also common for patients to experience upper respiratory illness and lymphadenopathy. Affected individuals may remain contagious for 10 – 14 days, and the symptoms can last for 7 – 21 days.

Vernal keratoconjunctivitis manifests as itchiness, the sensation of having a foreign body in the eye, light sensitivity, mucus discharge, and inflammation of the conjunctiva. These symptoms, which range from mild to severe, can interrupt daily activities. Corneal signs of this condition include pint-sized epithelial erosions and keratitis. It’s also common for patients to experience episodes during the winter months.

Keratoconjunctivitis sicca presents with chronic but often intermittent symptoms such as burning, stinging, foreign body sensation, light sensitivity, eye fatigue, a sense of heavy eyelids, itchiness, excessive tearing, watery discharge, and blurred vision. These symptoms often worsen with activities like reading, computer use, and driving when the natural blink reflex is decreased.

Superior limbic keratoconjunctivitis displays symptoms such as burning, irritation, and the sensation of a foreign body in the eye. Symptoms are typically chronic with gradual clearing but may have periods of remission. The severity and duration of the disease can lead to conjunctival overgrowth or pannus on the cornea.

Testing for Keratoconjunctivitis

Whether the cause of your eye problem is known or not, your doctor will conduct a series of tests and evaluations to better understand what could be causing your discomfort. This could involve several stages:

– The doctor may test your vision by checking if your sight improves with corrective lenses.
– They will also look at how your pupil reacts to light.
– The movement of your eyes will be assessed to check for any abnormalities.
– The doctor will test your peripheral vision by doing a quick ‘confrontation visual field’ test.
– They’ll measure the pressure inside your eye, this is important in figuring out if you have conditions like glaucoma.
– The doctor will conduct an external examination to check for any swelling or redness around your eye. They will also assess if there’s any swelling in the preauricular lymph nodes, which are located near your ear.
– Your eyelid will be thoroughly checked for anything out of the ordinary like changes in color, swelling, or rashes. They’ll also see if there’s an unusual discharge from your eyes.

– Discharges can be different types – ‘purulent’ which appears again soon after being cleaned off, ‘mucoid’ which sticks to the eyelashes, and ‘watery’ which is clear and ample. If you have a purulent discharge, a sample of it may be taken for testing.

– The underside of your eyelids will be checked for any abnormal bumps or growths.

Your doctor will closely examine the white part of your eyes and the inside of your eyelids for inflammation or swelling. They may use tools like a Wood lamp, slit-lamp microscope, or ophthalmoscope along with a blue light to thoroughly examine your cornea. If they suspect a herpetic infection (caused by the herpes virus), they will check for any specific patterns or lesions on your cornea.

In case of specific suspicions:
– The ‘Schirmer test’ may be done if keratoconjunctivitis sicca (dry eye syndrome) is suspected, to check how much tears your eyes are producing.
– If a herpetic viral infection is suspected, the sensibility of your cornea might be tested, as this kind of infection can numb your cornea.
– Testing the saltiness of your tears has become a popular method of detecting keratoconjunctivitis sicca (dry eye syndrome).
– For suspected epidemic keratoconjunctivitis (a type of highly contagious pink eye), a rapid sequence adenoviral test may be done, however, this condition is most commonly diagnosed clinically.
– If dry eye syndrome is suspected, you might be tested for Sjogren’s syndrome. It usually involves testing your blood for particular antibodies.

Treatment Options for Keratoconjunctivitis

When it comes to treating different types of eye infections, the approach will often depend on the specific cause:

Epidemic Keratoconjunctivitis, a very contagious viral infection, is usually managed by trying to prevent its spread. Because it can be transferred through contact with infected hands, objects, or medical equipment, thorough hand washing and the clean-up of household or medical office items are extremely important. Recovering from this infection can take a while, so patients and their families should be reassured that lingering symptoms are not uncommon. While there’s no definitive treatment for this condition, using artificial tears, applying cool compresses, and in some cases, using allergy eye drops, can help ease symptoms. Some research has suggested potential future treatments using certain antiviral eye drops.

Vernal Keratoconjunctivitis tends to need a team approach for treatment, potentially involving eye specialists. This condition often requires a careful balance of managing symptoms and avoiding unwanted side effects from medication. First-line treatments include lubricating products like preservative-free artificial tears, gels, or ointments, along with cool compresses and eyelid scrubs to help remove any possible allergens from the eyes. Allergy eye drops may be enough for mild cases, while stronger treatments like mast cell stabilizers can control symptoms in moderate cases. Other options for more severe cases can include using a mix of allergy eye drops/mast cell stabilizers, systemic (whole-body) antihistamines, topical non-steroidal anti-inflammatory drugs (NSAIDs), and topical corticosteroids. However, because corticosteroids can sometimes increase pressure in the eye, close monitoring is crucial. For severe, persistent cases, long-term treatment with medication to modulate the immune system, such as cyclosporine and tacrolimus, can be beneficial.

Keratoconjunctivitis Sicca, or dry eye disease, is often initially managed conservatively with treatments like free artificial tears, gels, and ointments, as well as warm compresses and eyelid scrubs. Supplements such as oral flaxseed oil and fish oil have shown usefulness in alleviating symptoms. Certain procedures can help preserve the tear film on the eye surface, and medications that fight inflammation like cyclosporine A, tacrolimus, and lifitegrast can be used. Short courses of topical steroids can also aid in symptom relief, but checks on intraocular pressure are necessary. Low doses of oral doxycycline can also be beneficial due to its unique anti-inflammatory properties. Another recent development in treatment is the topical use of autologous serum drops made from the patient’s blood, which can inhibit the inflammatory process contributing to dry eye. This treatment may however be expensive. A combined approach of the aforementioned treatments is often needed for adequate symptom relief.

In the case of Superior Limbic Keratoconjunctivitis, the first approach is using treatments like preservative-free artificial tears, gels, and ointments. Other topical treatments include mast-cell stabilizers, anti-histamines, vitamin A, and non-steroidal anti-inflammatories. Blocking the small openings in the corner of the eyes (puncta) can help increase eye surface lubrication. Chemocautery, a procedure that burns and therefore destroys the affected tissue in the eyelid resulting in symptom relief, and surgical eyelid resection can be highly effective treatments. Liquid nitrogen cryotherapy can also be used to treat affected areas and generally results in long-term symptom relief, although repeat treatments may be necessary.

What else can Keratoconjunctivitis be?

Patients with keratoconjunctivitis usually come in with red, irritated eyes. So, the doctor might want to rule out other conditions that share similar symptoms. These could be:

• Several types of conjunctivitis, like bacterial, fungal, viral, chemical exposure, or toxic
• Episcleritis or scleritis, inflammation of the white part of the eye
• Uveitis or Iritis, inflammation of the middle layer of the eye
• Endophthalmitis, an inflammation of the interior of the eye
• Corneal abrasion or ulcer, damage to the clear front surface of the eye
• Corneal foreign body, any object that is stuck on the cornea
• Acute angle closure glaucoma, a sudden increase in eye pressure
• Subconjunctival hemorrhage, a burst blood vessel in the eye

From the list above, conditions that need urgent attention are acute angle closure glaucoma, endophthalmitis, corneal ulcer, corneal foreign body, and uveitis/iritis. If a doctor suspects any of these conditions, the patient should be referred to an eye specialist.

Signs or symptoms that suggest the patient should be referred to an eye specialist right away include:

• A history of a foreign body in the eye or trauma
• Higher pressure inside the eye
• A pupil that isn’t the same size as the other or doesn’t react to light
• A big drop in how well they can see
• Pain so bad it keeps them from opening their eye or keeping it open
• A cornea that’s not clear
• Extremely fast discharge from the eye that’s filled with pus

What to expect with Keratoconjunctivitis

Viral keratoconjunctivitis, or epidemic keratoconjunctivitis, is a disease that typically gets better on its own. However, it can take two to three weeks to completely clear up. While it’s possible to get it again from another viral infection, serious complications are rare.

Similarly, vernal keratoconjunctivitis usually isn’t serious and gets better on its own. It often clears up on its own as a person grows older, especially during the tween or teen years. If symptoms last longer than this, which can happen in as many as 12% of patients, it’s typically considered a change to atopic keratoconjunctivitis. This looks and feels similar and is treated the same way, but typically has to be treated for a longer period of time.

Keratoconjunctivitis sicca varies widely in how serious it is. In most patients, symptoms can be managed effectively by sticking to a regular treatment plan. However, this doesn’t represent a total recovery from the disease, though it does allow symptoms to be well-managed. Changes in the environment, like climate or air pollution changes, can also cause symptoms to clear up. It’s not uncommon for patients whose symptoms are well-managed to have occasional flare-ups that require a temporary increase in treatment.

Treatment of superior limbic conjunctivitis is often very successful. In cases where the regular treatments don’t ease symptoms or aren’t successful, more aggressive treatments, such as chemical therapy or surgical removal of a part of the conjunctiva, are often successful.

Possible Complications When Diagnosed with Keratoconjunctivitis

: The possible complications of keratoconjunctivitis arise from ongoing inflammation, persistent eye rubbing, and even from certain treatments. Even though it’s uncommon, long-standing inflammation in the conjunctiva and cornea can lead to various complex conditions like symblepharon, scar tissue formation in the conjunctiva, shortage of limbal stem cells, and scarring on the cornea. Forceful and continuous eye rubbing can cause the drooping of eyelids, early cataract development, and is linked with the onset of keratoconus, a vision-threatening condition that affects the cornea.

Healthcare practitioners should also be mindful of the possible side-effects of medications. For example, using topical corticosteroids has the risk of raising the pressure inside the eyes, which can lead to steroid-induced glaucoma, a serious condition that can’t be reversed and threatens vision. Both topical and systemic steroids can also accelerate the development of cataracts. Moreover, using topical corticosteroids can make patients susceptible to the reactivation of ocular herpes simplex or allow the progression of serious eye infections caused by herpes or bacteria. Therefore, it’s crucial for healthcare providers to rule out herpes and bacterial infections before starting topical corticosteroid treatment.

Possible complications include:

• Prolonged inflammation leading to complex conditions
• Aggressive eye rubbing resulting in drooping eyelids and early cataract formation
• Side-effects of topical corticosteroids, including increased pressure inside the eyes,
• Steroid-induced glaucoma, a serious condition that can’t be reversed
• Accelerated cataract formation
• Susceptibility to the reactivation of ocular herpes simplex or serious eye infections

Preventing Keratoconjunctivitis

It’s important for patients to understand that recovery can often take a while, even if they follow their treatment plan to the letter. Instant relief of symptoms is usually not the case. Having a clear and open conversation with patients or their parents about what to expect can help avoid unnecessary, time-consuming, and costly visits to their regular doctor, an urgent care center, or the emergency room.

However, patients should also be given specific advice on red flags to watch out for during treatment. This includes: a decrease in their vision, worsening pain, an increase in sensitivity to light (photophobia), worsening discharge, or no improvement after a week of treatment.