CLINICAL
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Allergic Conjunctivitis
Take this ding out of spring
JOSH JOHNSTON, O.D., F.A.A.O., ATLANTA
With spring comes the pollen assault, which causes allergic conjunctivitis.
Diagnosing and managing this condition is well within our scope of practice, as we are eye experts, knowledgeable in the latest treatments and able to prescribe them. The problem is that three barriers hinder our ability to help these patients: (1) Patients get so used to their signs and symptoms that they accept them, rather than seeking help; (2) they self-treat with OTC products (which provide varying levels of relief), never contacting us; and (3) patients don’t realize we can help them, as many think of us as experts in optics alone.
ICD-9 or CPT Codes
• 372.14 other chronic allergic conjunctivitis
• 372.00 acute conjunctivitis, unspecified
• 372.05 acute atopic conjunctivitis
• 372.1 chronic conjunctivitis
• 372.10 chronic conjunctivitis, unspecified
• 372.13 vernal conjunctivitis
To break these barriers, we must actively ask patients about the symptoms and signs of allergic conjunctivitis on history forms, inquire again during peak allergy seasons and educate them that we can prescribe therapeutics that have quick onsets and long durations of action, all while having low side effect profiles.
Here, I discuss the etiology, symptoms, clinical signs, management options as well as the ICD-9 codes associated with allergic conjunctivitis.
Etiology
Allergic conjunctivitis falls under two categories: seasonal and perennial (animal dander, dust, etc.). Both make up 90% to 95% of all ocular allergies and are Type 1 or combined IgE-dependent hypersensitivity inflammatory reactions.
Allergens pass through the conjunctiva after exposure, and the inflammatory cascade begins with mast cell degranulation and the release of inflammatory mediators, such as histamine. This cascade of events then causes patients to become symptomatic and show signs.
What’s Coming Up?
• The Dry Eye Disease Exam
• Epidemic Keratoconjunctivitis
The severity of allergic conjunctivitis reactions depend on numerous factors, such as the allergen load size, exposure length and tear film volume that can dilute the allergen.
Of interest: Dry eye disease (DED) patients have a reduced tear film, creating a higher concentration of allergen in the tear film, as well as a delayed clearance of the allergen, which can make these symptoms worse in these patients. As underlying inflammation plays a role in both allergic conjunctivitis and DED, these two conditions have a clear co-morbidity.
Symptoms
► Itching
► Burning
Clinical signs
► Chemosis
► Conjunctival injection
► Eyelid edema
► Tearing
Management options
Allergic conjunctivitis management is comprised of the following:
► Eye wash/artificial tears. These work to clear allergens from the tear film.
► OTC antihistamines. Non-prescription options can alleviate symptoms and clinical signs for some patients. That said, they have low affinities for histamine receptors, short durations of action, don’t prevent mast cell degranulation, require frequent dosing and typically have more side effects, such as punctate keratitis due to high amounts of toxic preservatives, when compared with prescription topical therapies.
► Prescription anti-histamines/mast cell stabilizers. Most act by blocking H1 and H2 receptors, decrease the amount of allergens that bind to mast cells, causing mast cell degranulation to reduce the release of allergic mediators, and many work as fast as three minutes and, in most patients, provide relief for as long as 24 hours.
(To prevent contact lens dropout in seasonal allergy patients, pre-treat with a topical antihistamine prior to allergy season.)
► Topical steroids. These are ideal for allergic reactions that cannot be controlled by the above management options. Typically, these patients are prescribed low-concentration corticosteroids, which have a lower propensity to cause side effects, such as cataracts.
► Daily disposable contact lenses. For all allergic contact lens patients, prescribe daily disposable lenses, as they do not contain a build up of the allergen(s).
Future treatment options
Future novel medications will aim to have a quick onset of action with a lengthy duration and be highly selective with a high affinity for H1, H2 and H4 receptors. The goal is to accomplish this with no side effects.
Bottom line
Allergic conjunctivitis can greatly affect our patients’ quality of life, especially contact lens wearers. Let’s actively identify and educate these patients that we have the skill and prescription rights to provide relief. OM
Dr. Johnston practices at Georgia Eye Partners. He focuses on ocular surface disease and has extensive experience in comanaging cataract and refractive surgery patients. E-mail him at drj@gaeyepartners.com, or visit tinyurl.com/OMcomment to comment. |