Urticaria is a vascular reactive skin disease. It is often associated with drugs, food, pollen, infections, physical stimuli and genetic factors; clinically, it is characterized by the sudden appearance of pruritic erythema and wind masses on the skin and mucous membranes, with sudden onset and abatement, and no traces left after elimination. Urticaria related to sunlight is called solar urticaria, urticaria related to cold stimulation is called cold urticaria, urticaria occurring on the lips, eyelids, foreskin and other parts of the giant urticaria is called angioneurotic edema; urticaria manifesting as small wind clusters is called cholinergic urticaria.
Diagnosis
I. Medical history
(a) Often associated with the use of certain drugs, diet, inhalation of dust, infection, sun exposure, cold stimulation and intestinal parasitic diseases.
(b) The rash is indefinite, comes on suddenly, usually subsides within 24 hours, and leaves no trace after elimination.
(c) Self-perceived itching of varying degrees.
(d) Generally no systemic symptoms, a few have abdominal pain, itchy throat and dyspnea.
(5) The duration of the disease is variable, most of them are cured within 1 week, but a few of them are several months to several years.
(b) Physical signs
(a) The basic damage is a pink, red or normal colored wind mass of different shapes and sizes.
(b) Some of the lesions are surrounded by a red or white halo.
(c) Damage occurring on the eyelids, lips and foreskin is often limited edema, with unclear borders, light red or pale color, smooth and shiny, translucent appearance.
III. Laboratory tests
(a) Routine blood tests: an increase in total peripheral blood leukocytes and neutrophils is seen in infected urticaria; an increase in eosinophilic erythrocytes is seen in urticaria caused by drugs or intestinal parasites.
(b) Ice cube test: ice cube placed on the forearm for a few moments, the presence of wind masses when removed and warmed up is positive; meaningful for the diagnosis of cold urticaria.
(c) Skin scratch test: scratching with a blunt instrument on the patient’s forearm, and a triad of red lines, erythema and edematous erythema at the scratch is a positive scratch test, seen in artificial urticaria.
Differential diagnosis
The disease should be differentiated from erythema multiforme, drug rash, insect bite dermatitis and urticarial vasculitis.
Treatment
I. Treatment principles
(a) Remove the causative factors as far as possible, those with signs of infection should be anti-infective.
(2) reasonable use of anti-inflammatory mediators.
(3) stabilize the lysosomal membrane and inhibit the liberation of inflammatory mediators.
(4) Reduce the vascularity.
II. Treatment plan
(a) acute urticaria: generally controlled by H1 receptor antagonists, and according to the possible causes of treatment; if respiratory distress occurs, glucocorticoids should be used in full doses as soon as possible, and then reduced or discontinued after the disease is controlled.
(b) Chronic urticaria: generally use the combination of two different types of H1 receptor antagonists, or H2 receptor antagonists or doxorubicin for those who cannot be controlled; small doses of glucocorticoids can be added for control, and the dose should be gradually reduced to maintain at least 2 to 3 months after the disease is controlled.
(iii) cold urticaria: generally use cyproheptadine, doxorubicin, ketorolactam, ketotifen; VitE also has a certain therapeutic effect.
(iv) skin scarring: often use Antalac, brain quarryzine, doxorubicin and Xanthamine, after the control of the disease can be maintained with Xanthamine.
(E) angioneurotic edema: antihistamines are often effective; if there is laryngeal edema, 1% epinephrine 0.5-1ml should be injected subcutaneously immediately (caution for those with cardiovascular disease); if it cannot be controlled, intravenous dexamethasone 5-10mg should be administered; hereditary angioneurotic edema can be treated with cerebral quarryzine.