Allergen Profile, Horse, IgE With Component Reflex

Serum

1 mL

0.5 mL (Note: This volume does not allow for repeat testing.)

Gel-barrier tube

The diagnostic assessment of allergy starts with the patient’s clinical history and examination and is followed by an extract-based analysis to confirm the presence of specific IgE (sIgE) antibody.¹ sIgE is necessary but not sufficient for eliciting an allergic response and thus generating a definitive diagnosis of allergic disease. Testing utilizing allergenic extracts does not lend itself to the differentiation of primary sensitization from a cross-reactivity-driven response because of the complexity of the extracts. Extracts contain most of the extractable allergenic components from the suspected sensitizer. However it is often not possible to predict the relative risk of having a systemic allergic reaction using an extract-based diagnostic test. Component Resolved Diagnostics (CRD) refers to the use of purified or recombinant allergens in the serologic assessment of individuals who suffer reproducible hypersensitivity reactions with exposures to an allergen at a dose tolerated by non-allergic individuals.^1,2 This approach offers advantages over the use of a complete extract, especially in polysensitized individuals, given its usefulness for distinguishing between sensitizations specific to singular species and sensitizations due to cross-reactivity.³

Allergen-specific IgE assays do not demonstrate absolute positive and negative predictive values for allergic disease. Clinical history must be incorporated into the diagnostic determination. Although the use of component resolved IgE testing may enhance the evaluation of potentially allergic individuals over the use of whole extracts alone, it cannot yet replace clinical history and oral food challenge in most cases. Sensitization against thus far unidentified determinants that are not found in the whole extract or in components might cause symptoms in rare cases.

Thermo Fisher ImmunoCAP® Allergen-specific IgE

Equ c 1

The horse allergen, Equ c 1, was one of the first major allergens to be isolated, cloned and characterized^4-6 and up to 76% of patients with horse allergy react to Equ c 1.^7-9 Equ c 1 is generally accepted as the major horse allergen, although the sensitization profile among horse sensitized individuals has not been comprehensively characterized.¹⁰ There is a close structural relationship between Equ c 1 and a number of proteins from other species including cat (Fel d 4), dog (Can f 6), rabbit (Ory c 4), rat (Rat n 1) and mouse (Mus m 1).^7,11-13 Equ c 1 and homologous allergens is thought to contribute to multi-sensitization and symptoms in individuals allergic to mammals. Allergic sensitization to multiple animals without exposure to specific species may put patients at risk for unexpected respiratory symptoms may develop after an occasional animal contact.¹⁴ Asthmatic children sensitized to Equ c 1 have been shown to be at a greater risk of having more severe symptoms.^15-17