Quincke's edema

Etiology and pathomorphological mechanisms

Angioedema is most frequently a prominent clinical manifestation of an acute allergic reaction to insect stings (insect allergy), food products, or medications. Its development is generally based on the classic reaginic type of hypersensitivity, mediated by immunoglobulin E (IgE).

The histological picture of Quincke's edema is practically identical to the changes observed in urticaria. Local vasodilation of the microvasculature (arterioles and capillaries) occurs in the tissues, accompanied by local edema and moderate perivascular infiltration by lymphocytes. The main difference lies in the depth of the lesion: whereas in urticaria the changes are localized predominantly in the papillary dermis, in angioedema the pathological process extends significantly deeper, involving the subcutaneous adipose tissue and mucous membranes.

Furthermore, allergic syndromes in the form of urticarial exanthema and Quincke's edema may develop as part of the early (migratory) phase of parasitic infestations. With a high intensity of infection, the migration of larvae (e.g., Ascaris) through the bloodstream is accompanied by intoxication, hypereosinophilia (20% or more), and the formation of "transient" eosinophilic pulmonary infiltrates (Löffler's syndrome).

Clinical presentation and preferred localizations

The primary manifestation of Quincke's edema is the sudden development of localized tissue swelling. The pathology has its "preferred" sites of localization—these are areas of the body with well-developed and loose subcutaneous adipose tissue.

Such zones include:

• Facial area: eyelids, lips, tip of the nose, auricles.
• Oral cavity and respiratory tract: tongue, mucous membranes.
• Other zones: distal upper and lower extremities, external genitalia.

In severe cases, acute localized allergic reactions may be accompanied by systemic manifestations. The patient may exhibit fever, joint syndrome (arthralgia), and pronounced abdominal pain. In rare cases, involvement of internal organs is possible, leading to reactive pancreatitis, allergic myocarditis, or arthritis.

Life-threatening complications

The most formidable and potentially fatal course of Quincke's edema is isolated or combined laryngeal edema.

Clinically, this condition manifests as croup syndrome, i.e., acute upper airway obstruction. The patient experiences rapidly progressive inspiratory dyspnea, which requires immediate emergency medical care. Without timely and adequate intervention, airway occlusion inevitably leads to asphyxia.

Principles of treatment and emergency care

Therapy for acute allergic reactions is based on several key principles aimed at the rapid relief of symptoms and the elimination of the trigger from the body.

1. Cessation of exposure. Immediate discontinuation of allergen exposure.
2. Elimination therapy. Acceleration of the elimination of already circulating allergens. The patient is prescribed generous alkaline drinks, enzyme preparations, and, if necessary, diuretics. Dietary management includes individual elimination diets (effectiveness assessed after 1 month).
3. Pharmacotherapy. In acute situations (especially when urticaria is combined with angioedema), medications are administered parenterally:
4. Glucocorticosteroids (GCS): prednisolone. In severe cases, they are prescribed in a short course (3–10 days) at a dose of 1 mg/kg of body weight, with a maximum daily dose of 40 mg.
5. H1-antihistamines: injectable forms of sedating antihistamines (chloropyramine, diphenhydramine, clemastine, promethazine) or other agents of the group (hydroxyzine, astemizole, terfenadine) are used.

Important: When laryngeal edema develops, the priority task, alongside the administration of hormonal and antihistamine agents, is to implement measures to restore and maintain airway patency.

What else to study on this topic

• Löffler's syndrome and pulmonary manifestations in parasitic infestations.
• Principles of elimination diet therapy in allergic dermatoses.
• Basic therapy for urticaria: non-sedating antihistamines.
• Complications of severe urticaria (myocarditis, pancreatitis).

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.