What is allergic eye disease?
An immune response is how the body recognises and defends itself against substances that appear harmful, usually by producing specific blood proteins (antibodies) against them. An allergy is a reaction by the body's immune system to a particular substance (an allergen) that is usually harmless, such as grass or tree pollens in the air. Different allergens affect different tissues, and their effects can be mild or serious.
In the eye, allergic reactions can cause conjunctivitis: the conjunctiva (the tissue covering the white of the eye and lining the inside of the eyelids) becomes swollen and sore. Severe allergic eye disease may also affect the cornea (the clear, front part of the eye), causing keratoconjunctivitis.
Vernal keratoconjunctivitis (VKC) and atopic keratoconjunctivitis (AKC) are rare types of severe allergic eye disease. VKC usually develops in children and is more common in boys; AKC can affect children and adults. These conditions usually affect both eyes and make them red, itchy, sore, watery and sensitive to light. Both conditions can damage the cornea, which can affect eyesight and lead to blindness. Treatment is essential to save eyesight.
Treatments for severe allergic eye disease
Both conditions are treated with medicines that try to block the allergic reaction and reduce swelling. Symptoms may get better with medicines given as eye drops, but if these don't work, other medicines may be taken by mouth or given as an injection (systemic medicines). Systemic medicines that are often used to treat severe allergic eye disease include ones that target or suppress the immune response, such as anti‑inflammatory medicines and antibodies.
Why we did this Cochrane Review
We wanted to find out which systemic treatments work best for severe allergic eye disease in children and young people.
What did we do?
We searched for studies that looked at systemic medicines to treat severe allergic eye disease in children and young people under 16 years of age. We wanted to find studies that compared a single medicine with a placebo (dummy) medicine, or studies that compared two or more medicines against each other.
We looked for randomised controlled studies, in which the treatments people received were decided at random, because these studies usually give the most reliable evidence about the effects of a treatment.
Search date: We searched for evidence published up to 17 February 2020.
What we found
We found no randomised controlled studies in children and young people with severe allergic eye disease treated by systemic medicines.
Conclusions
There is no evidence from randomised controlled studies about how well systemic medicines work for severe allergic eye disease in children and young people aged under 16 years.
Research is needed to investigate how well systemic medicines work to treat severe allergic eye disease in children and young people, and to learn about any unwanted effects these medicines might cause.
There is currently no evidence from randomised controlled trials regarding the safety and efficacy of systemic treatments for VKC and AKC. Trials are required to test efficacy and safety of current and future treatments. Outcome measures need to be developed which can capture both objective clinical and patient-reported aspects of the condition and treatments.
Atopic keratoconjunctivitis (AKC) and vernal keratoconjunctivitis (VKC) are severe and potentially sight-threatening allergic eye diseases characterised by chronic inflammation of the ocular surface. Both topical and systemic treatments are used. This Cochrane Review focuses on systemic treatments.
To assess the effects of systemic treatments (including corticosteroids, NSAIDS, immunomodulators, and monoclonal antibodies), alone or in combination, compared to placebo or other systemic or topical treatment, for severe AKC and VKC in children and young people up to the age of 16 years.
We searched CENTRAL, Ovid MEDLINE, Ovid Embase, the ISRCTN registry, ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). There were no restrictions to language or year of publication. We last searched the electronic databases on 17 February 2020.
We searched for randomised controlled trials (RCTs) that involved systemic treatments in children aged up to 16 years with a clinical diagnosis of AKC or VKC. We planned to include studies that evaluated a single systemic medication versus placebo, and studies that compared two or multiple active treatments.
We used standard methods expected by Cochrane.
No trial met the inclusion criteria of this Cochrane Review. No RCTs have been carried out on this topic.