Management of Patients with Allergic Disorders

Hypersensitivity

• Excessive immune response to stimuli, generally not reactive on first exposure due to sensitization.
• Type I hypersensitivity (Anaphylaxis) is the most severe, rapid onset reaction, involving edema, hypotension, and bronchospasm.
• Cytotoxic (Type II) hypersensitivity involves the immune system misidentifying normal body components as foreign.
• Immune Complex (Type III) hypersensitivity involves antigens bonding with antibodies, leading to tissue injury when deposited in tissues.
• Delayed-Type (Type IV) hypersensitivity manifests 24 to 72 hours post-exposure and is characterized by T cell-mediated damage.

Diagnostic Evaluation

• Eosinophils in a Complete Blood Count may indicate allergic reactions, with percentages over 5% suggesting eosinophilia.
• High serum IgE levels can support allergic disease diagnosis.
• Skin tests involve applying allergen samples to identify specific sensitivities and reactions.
• The Radioallergosorbent Test measures allergen-specific IgE via blood serum testing.

Antihistamines

• First-generation antihistamines (e.g., diphenhydramine, hydroxyzine) cause drowsiness and exert anticholinergic effects.
• Second-generation antihistamines (e.g., cetirizine, loratadine) have fewer side effects and lower sedation incidence.
• Indicated for allergic conjunctivitis, urticaria, nasal symptoms, and adjunctive therapy in anaphylaxis.

Nursing Implementation for Antihistamines

• Administer one hour prior or two hours post meals to optimize effects.
• Advise use of sugarless candies for dry mouth relief.
• Ensure safety measures to prevent falls and injuries.
• Encourage increased fluid intake to combat thickened secretions.
• Implement skin care strategies to avoid breakdown and complications.
• Recommend avoiding alcohol, as it can enhance sedation.

Anaphylaxis

• A systemic hypersensitivity reaction with symptoms including hypotension, airway obstruction, and severe hypoxia.
• Common triggers: latex, penicillin, local anesthetics; reactions arise within minutes of exposure.
• Initial signs include generalized itching, coughing, respiratory difficulty, and potential loss of consciousness.
• Management focuses on immediate epinephrine administration to counteract symptoms.

Contact Dermatitis

• Caused by direct exposure to allergens or irritants, leading to sensitization characterized by a pruritic rash post-exposure.
• Symptoms include erythema, edema, and vesicular lesions.
• Effective treatment involves removing irritants and employing topical glucocorticoids.

Atopic Dermatitis

• Also known as atopic eczema, is characterized by chronic inflammation and skin hyperreactivity.
• Eosinophilia and elevated serum IgE levels confirm the allergenic basis.
• Complications include secondary infections and increased sensitivity to irritants.
• Common symptoms include dry, scaling skin, lichens, and intense pruritus.

Dermatitis Medicamentosa (Drug Reactions)

• Type I hypersensitivity presenting with skin rashes following medication exposure.
• Rashes are vivid and resolve quickly upon discontinuation of the triggering medication.
• Patients must be informed of their hypersensitivity and carry identification to avoid future exposure.

Food Allergy

• Type I IgE-mediated reaction affecting about 2% of adults, often due to genetic predisposition and early exposure.
• Common allergens include seafood (e.g., shellfish, fish), legumes (peanuts, beans), seeds, tree nuts, milk, and chocolate.

This quiz covers the management of patients with various allergic disorders, focusing on hypersensitivity, antihistamines, anaphylaxis, and specific types of dermatitis. Participants will explore the mechanisms and treatments for conditions such as food allergies and drug reactions. Perfect for healthcare professionals seeking to enhance their understanding of allergic conditions.