Immunoglobulin E (IgE) Regulation and Biology

immunoglobulin e
Normally present at very low levels in plasma, antibodies of the immunoglobulin E (IgE) isotype were first discovered in 1967, decades after the description of IgA, IgG, and IM. IgE antibodies are produced primarily by plasma cells in mucosal-associated lymphoid tissue and their levels are uniformly elevated in patients suffering from atopic conditions like allergic rhinitis, asthma and atopic dermatitis. Production of allergen-specific IgE in atopic individuals is driven both by a genetic predisposition to the synthesis of this isotype as well as by environmental factors, including chronic allergen exposure. (more…)

Oral Food Challenges & Relationship to Allergen-Specific IgE Levels

Diagnosis of food hypersensitivity is a clinical challenge and the only current definitive test is the Double Blind Placebo-Controlled Food Challenges. Although the Double Blind Placebo-Controlled Food Challenges is the current gold standard, it is difficult to perform and is very time-consuming. Hence, researchers are continually evaluating new tests and assessing the value of the available serum tests. (more…)

Atopy Patch Test Accuracy in Diagnosing Hypersensitivity to Cow’s Milk & Hen’s Egg

Over the last 5 years some studies have suggested that the atopy patch test (APT) may be a useful test in atopic dermatitis children who have suspected food hypersensitivity and may even obviate the need for oral challenges. An alternative test to oral allergy challenges with high sensitivity and specificity would be helpful in the diagnosis of food hypersensitivity. (more…)

Allergic Reactions To Penicillin and Skin Test Evaluation via Intradermal Injection

Intradermal Injection
This study compared the diagnostic value of intradermal tests and patch tests in 20 patients with non-immediate reactions to penicillin (none had IgE antibodies to benzylpenicillin or amoxicillin detectable using a commercial RAST [radioallergosorbent test] method), using 30 patients tolerant to penicillin as controls. Intradermal tests assessed reactivity to injection of major and minor determinants of benzylpenicillin, amoxicillin and ampicillin. Allergy patch testing involved the same hapten solutions used for intradermal testing, either embedded in a patch disk or mixed with petrolatum. (more…)

Allergen Vaccine and Allergenic Source of Material

Allergen Vaccine
Being an immunological disease, the characteristics of allergy are those of specificity and memory. Regardless of whether the clinical manifestation is rhinoconjunctivitis, rhinitis, or asthma, the underlying immunological response disorder is based on the adverse reactions of cells in the immune system upon contact with allergens. These cells are specific for epitopes that are structural parts of allergens present in the allergenic source material. Two types of cells (i.e., T cells and B-cells) produce receptor molecules (i.e., T-cell receptors and immunoglobulin [IgE] antibodies) that, through high-affinity interactions with the allergen, efficiently catalyze the presence of even minute amounts of allergens into clinical symptoms, the extreme consequence of which may be life-threatening to the patient. (more…)

Penicillin Allergy Testing: Re-prescription Of Penicillin After Allergic-Like Events

Penicillin Allergy Testing
Suspected drug allergy is not easy to investigate. In the UK, few centers have the necessary facilities and expertise, the evidence base of the available diagnostic tests is not robust, and their interpretation of drug allergy reaction is not straightforward. This has led many clinicians increasingly to rely on the patient’s recollection of previous response to individual allergies medicines when anticipating the likely tolerability of future exposure. (more…)

Systemic Allergic Reactions: Causes, Reaction, and Treatment

Systemic Allergic Reactions
Systemic allergic reactions are a relatively common clinical emergency. In their mildest form, they may just manifest as systemic cutaneous reactions with pruritis, allergy urticaria and angioedema. In more severe cases there are cardiorespiratory symptoms such as stridor, wheeze, difficulty in breathing or hypotension. Anaphylaxis has been defined as a ‘severe, life-threatening generalized or systemic hypersensitivity reaction’. The prevalence of systemic allergic reactions is unclear because of the lack of a clear, consistent definition and large prospective population studies. (more…)

EpiPen Training For Kids With Food Allergies

EpiPen Training For Children
Families frequently do not use their self-injectable adrenaline device, even when their kids is experiencing a potentially life-threatening cardiorespiratory allergic reaction to a food allergen. Fatal food allergy anaphylaxis is rare but well recognized and the early use of intramuscular adrenaline may be life-saving. (more…)

Atopic Dermatitis in Children: Triggers and Treatment

atopic dermatitis
Atopic dermatitis is a chronic inflammatory condition of the skin which usually starts in infancy. It is sometimes called ‘atopic eczema’ or even simply ‘eczema’. Recently, the term ‘atopic eczema dermatitis syndrome’ or eczema symptoms or infantile eczema has also been proposed to indicate the varied nature of this disease. The diagnosis is based on clinical features of a chronic itchy dermatitis with typical morphology and distribution and a relapsing and remitting course. (more…)

Allergy Skin Testing to Determine Allergies Causes

Allergy Skin Test
Allergy skin testing is probably the most susceptible and practical way to monitor for existing allergy sensitivity. Biological extracts of aeroallergens such as trees, dust mites, weeds, cockroaches, molds, and animal danders are offered for allergy testing. The most common and approved way to test is by putting a drop of antigen on the surface area of the patient’s skin and scratching or skin prick test with a lancet or sharp object. The most essential ancillary test to confirm the diagnosis of allergy is the skin test, which is the gold standard in this respect. The skin test final results must be viewed in light of the history to decide the importance of a positive test. (more…)

Next Page »