The Role of Allergy Testing in Eye Care

At some point in each of our lives, we will likely deal with an allergy: foods, medication, environmental, or otherwise. Allergies continue to change throughout our lives, as we grow out of some and into others. When we consider our patients’ ocular complaints, it is important to keep allergies in mind as a cause or contributing factor.

In diagnosing and treating our patients, allergy testing is a helpful tool that often gets overlooked. Until recently, few allergy testing options were available for in-office use by primary eye care providers, but that is changing. This can be a boon for our practices and for our patients with ocular allergies.

TURNING TO TESTING

A good patient history is vital in diagnosing and treating patients, but often we must turn to testing to aid us. There are multiple reasons to consider allergy testing. The most obvious is a patient presenting with ocular signs and symptoms of allergies: itchy, watery, painful, swollen, red, or burning eyes.^1,2

Ocular allergy includes disorders affecting the eyelid and conjunctiva: seasonal and perennial allergic conjunctivitis, contact blepharoconjunctivitis, and vernal and atopic keratoconjunctivitis.¹ Typically the cause is either environmental allergy or a reaction to a topical agent (an ocular medication, a preservative, or a component of makeup). Some allergic reactions are mediated by immunoglobulin E and others are not.

Allergy testing can help us to understand what our patients may be allergic to and advise them regarding how to eliminate or decrease their exposure. Testing can also help to indicate if the patient may benefit from more aggressive treatment, such as injections.

CONCOMITANT CONDITIONS

Another time to consider allergy testing is in the management of patients with dry eye. It is important to remember that the signs and symptoms of allergies and dryness overlap.¹ Both can coexist, exacerbating the symptoms of each other. Patients who think that they may have allergies, even though they don’t, may add to their dry eye symptoms by self-medicating with systemic antihistamines that they do not need.

Environmental allergies and food allergies should be considered in patients with chronic inflammatory problems. Food allergies and sensitivities can induce or worsen inflammation within the body. Typically a food elimination diet or allergy testing can aid in diagnosing these problems. Patients with inflammatory bowel disease (IBD), which includes ulcerative colitis and Crohn disease, can experience ocular manifestations including episcleritis, scleritis, iritis, and dry eye disease (DED).^3,4 In one study assessing the association of IBD with DED, 22% of patients with IBD had DED, whereas only 11% of control patients without IBD had DED.^3,4

ALLERGY TESTING OPTIONS

Few options for allergy testing are available to the primary eye care provider; among them are skin prick testing and serum-specific IgE testing. Until recently the only other option was to refer patients to an allergist. At present, testing for food allergies and full panels of environmental allergens are still only available through an allergist. But there now exist two options for testing for environmental allergens that can be performed in our own offices.

One is Doctor’s Rx Allergy Formula (Bausch + Lomb). This FDA-approved diagnostic test was developed by an ophthalmologist and purchased in 2015 by Bausch + Lomb.⁵ It offers 39 separate panels developed for different regions of the United States. Each panel tests for 58 different allergens along with two controls (Figure 1).⁵ The test is administered in approximately 3 minutes with plastic disposable skin-prick applicators; no needles or shots are needed (Figures 2 and 3). After 15 minutes, the patient’s results can be read, and the allergens that are identified can be discussed with the patient (Figure 4). Most insurance plans reimburse for this test.

Another in-office allergy testing option is offered by AllerFocus. Again, this test assesses for 58 allergens along with two controls. This FDA-approved skin-prick test takes approximately 10 to 15 minutes to administer.⁶ The company also offers customized sublingual immunotherapy based on each patient’s allergen testing results.⁶

BEFORE TESTING

Before office allergy testing is conducted, the patient should be given a list of medications and supplements to discontinue in order for the test to be valid. This will typically include antihistamines, sleep aids, nasal steroid sprays, selective serotonin reuptake inhibitors, some antacids, and other medications.⁷ Most of these should be stopped approximately 3 to 7 days before testing. For patients who have been taking daily oral antihistamines chronically for more than 1 year, these should be stopped more than 2 weeks before testing.⁷

KNOW YOUR ENEMIES

In this age of continually changing and improving medical technology, it is important to know what is available and how to incorporate it into our clinics. Allergy testing can be a valuable tool in many cases. Once allergens have been identified or ruled out, we are better equipped to make medical and lifestyle recommendations to help our patients.