Elevated levels of IgE indicate an IgE-mediated hypersensitivity, responsible for Type-1 (anaphylactic) allergic reactions. The reaction includes inflammation, constriction of smooth muscles, dilation of blood vessels, and irritation of nerve endings characteristic of allergic reactions. Clinical symptoms include inflammation, itching, congestion (bronchial), or hyperemia (ocular). In ocular allergies, tear concentrations of IgE may be high, while serum concentrations may be low, except in vernal conjunctivitis, indicating a localized vs. systemic response.
IgE (anaphylactic) ocular responses can be quite localized, may not be bilateral and include the following forms of conjunctivitis:
- GAC (General Allergic),
- SAC (Seasonal Allergic),
- PAC (Perennial Allergic),
- AKC (Atopic),
- GPC (Giant Papillary) and
- VKC (Vernal).
When using ocular IgE values, allergic inflammation is clearly distinguished from non-allergic inflammatory etiologies.
Elevated tear film IgE values indicate either an ocular allergy, or an allergic component of the inflammatory response to exotoxin (bacterial) or exfoliated necrotic tissue (viral). Because total ocular IgE increases with the severity of allergic response, determination of total tear IgE levels are useful in confirming a clinical diagnosis of allergic conjunctivitis and assessing the level of severity.
The ATD ocular lab test for IgE provides each clinician the diagnostic tool necessary to detect the concentration of total IgE in the tear film, in a system that is accurate, rapid and simple.