Urticaria Dr. Mohammad Arif Abid Dermatologist Rose dermatology cosmetic hospital www.doctorabid.com

Urticaria Acute Urticaria Description * Urticaria or hives is devided into acute and chronic forms, which is based on the duration of the hives Acute urticaria, by definition, lasts for Less than 6 weeks while chronic urticaria lasts more than 6 Unticaria is a pruritic, common. distinctive reaction pattern Transient, edematous, red plaques vary in size and shape. individua lesions last less than 24 hours.

Pathogenisis

History The etiology of most cases of urticaria is Difficult to find and in most causes are undetermined. Acute urticaria may occur at any age. It is more common in atopic individuals and is notoriously intensely pruritic. Hives are caused by histamine release induced by allergens such as medications, foods, airborne allergens. Angioedema is a histologically deeper variant of urticaria, and somewhat less pruritic.

Skin Findings The edematous plaques are pink to flesh- colored, and may be surrounded by a white or pink halo. Individual lesions vary in size, from 2mm papules to 3 cm wheals. They are typically round or oval in shape and can become polycyclic and confluent, The plaques change size and shape by peripheral extension, migrate and regress. This is a dynamic process and new lesions evolve as old oncs resolve bullae or purpura lessons appear with intense swelling

CLINICAL ASPECTS

CLINICAL ASPECTS

CLINICAL PRESENTATION.

SYMPTOMS.

Laboratory and Testing There are no routine studies for diagnostic confirmation of urticaria Biopsy is usually not needed for diagnosis of acute hives If urticarial vasculitis is suspected, a biopsy can help confirm this diagnosis n For the most part, urticaria is a clinical diagnosis

Differential Diagnosis Drug eruption, Viral exanthema, Bites(papular urticaria) ,Bullous pemphigoid, Urticarial vasculitis Hereditary angioedema

Treatment All suspected triggers, such as medications, food, inhalants, and injections should be discontinued. Antihistamines are typically administered initially sedating type 1 histamine receptor antagonists(e.g. hydroxyzine 10mg, 25mg, 50mg 100 mg, 10mg/5ml) can be helpful. but are limited by drowsiness. They are administered every four or six hours.

The non-sedating antihistamines(eg but may have to be used in combination with sedating H1 blocking agent They are taken one every 24 hours Prednisone is effective and can be given periodically and may work in people whose condition is difficult to control with antihistamines. Doxepin, a tricyclic antidepressant and an antihistamine, can be used in recalcitrant cases. Epinephrine is administered for extensive severe cases, but the effects may be short-lived.

Treatment 1. sedating type 1 histamine receptor antagonists 5. Epinephrine 4. Doxepin 3. Prednisone 2. The non-sedating antihistamines 1. sedating type 1 histamine receptor antagonists

Keep the patient cool. Cool, soothing baths can be suggested. Hot showers should be avoided as they only worsen the pruritus afterwards. Topical steroids are generally not effective.

> 6 weeks chronic urticaria Description Chronic urticaria is definned as urticaria lasting for more than 6 weeks. This variation of hives requires investigation to the etiology of the urticaria, which can require significant work up. > 6 weeks

History Chronic urticaria is usually easily diagnosed but presents a treatment and management dilemma. The underlying cause of chronic urticaria is discovered in only 5-25% of cases. People of all ages are affected, but the highest incidence is in young adults. The course of the disease is unpredictable, and can last months or years,

5 Is( CAUSES OF CHRONIC URTICARIA (most common): medications, foods additives Ingestants dust, feather, pollen Inhalants: drugs, stings, bites Injectants bacterial, viral, fungal, parasitic Infections such as chronic infections, thyroid discase, lupus crythe matosus, occult cancer Internal diseases

Skin Findings Clinically, chronic and acute urticarias are indistinguishable The edematous wheals and plaques are pink to red in color, figurate and annular, with central clearing Lesions vary in size from just millimeters to areas that can cover an entire hand. These plaques can be coalescing and polycyclic and change in size and shape over time, and migrate. Individual lesions resolve within 24 hours, while new lesions continue to appear

Laboratory and Testing The cause may be unclear after routine history and physical examination Laboratory tests may be ordered but are rely helpful. Tests to consider include a complete blood count, sinus x-rays to evaluate for sinusitis, dental x-rays to evaluate for an occult dental abscess, rapid streptococcal test or pharyngeal culture, and a thyroid-stimulating hormone and thyroid microsomal antibody test for autoimmune thyroid disease. Other tests may be acquired based on the physical signs and symptoms of the patient.

Tests to be helpful complete blood count sinus x-rays to evaluate for sinusitis dental x-rays to evaluate for an occult dental abscess rapid streptococcal test or pharyngeal culture thyroid-stimulating hormone and thyroid microsomal antibody Urine exam Stool exam

Differential Diagnosis Physical urticaria Erythema multiforme Urticarial vasculitis Bullous pemphigoid

Treatment Antihistamines(H1 type) are prescribed initially, most commonly diphenhydramine and hydroxyzine. They are the backbone of therapy for acute and chronic urticaria. Hydroxyzine 10-25 mg or diphenhydramine 25-50mg can be 4 hours, up to 100mg every 4 hours as ceded, but can be sedating Non sedating antihistamines(HI type) should be considered for daytime use, and include cetirizinc, desloratadine, cetirizine and fexofenadine.

Pearls Individual urticarial lesions are recurrent, migratory and pruritic, but tend to resolve in a 24-hour period, while new lesions appear. Some cases of chronic urticaria may be recurrent and not resolve after several months or years, etiology unknown. Urticarial vasculitis is a systemic disease that may be related to lupus erythematosus, which mimics chronic urticaria, but differs in that it leaves purpuric patches. Diagnosis is made via biopsy.

Physical urticaria Description Physaical uticaria is a brief attack of urticaria or hives induced by physical factors such as scratching, pressure, vibration, heat, cold and ultraviolet light The episode may be short-lived but recur with recurrent stimulation

History The major distinguishing feature is that those eruptions brief and usually self limited. Most of the episodes of unicaria last 1-6 hours dermographism is the most common physical urticaria, which is when hives are produced by rubbing and stroking the skin This entity can be triggered by viral infection, by antibiotic therapy or emotional upset, although the cause is usually not determined.

Dermographism

Pressure urticaria A deep, itchy, burning, or painful swelling occurring 2 to 6 hours after a pressure stimulus and lasting 8 to 72 hours is characteristic of this common form of physical urticaria. The disease is chronic, and the mean duration is 9 years

CHOLINERGIC URTICARIA Cholinergic urticaria is a varant of hives that begins within 1-20 minutes of over heating from excrcisc,exposure to heat or emotional stress. It may last for minutes to hours. It is more common in young patients and tends to be chronic

Exercise-induced anaphylaxis Patients develop pruritus, urticaria, respiratory distress, and hypotension after exercise. Symptoms may progress to angioedema, laryngeal edema, bronchospasm, and hypotension, and there is a high frequency of progression to upper airway distress and shock.

Solar urticaria Hives that occur in sun-exposed areas minutes after exposure to the sun and disappear in less than 1 hour are called solar urticaria.

Aquagenic pruritus

vibration urticarias

Cold urticaria Cold urticaria occurs with a sudden drop in air temperature or exposure to cold water This condition can be initiated after infection, drug therapy, or emotional stress

Skin Findings physical The physical unicartas may present with pruritic linear wheats after rubbing ,scratching, which is the definition as dermatographism This test can be prerformed in the fore arm by stroking a pencil Repeated deep swelling on prolonged pressure site is pressure urticarial Annular hive lesions, 2- mm in diameter, surrounded by extensive red flare are characteristic of cholinergic urticaria Cold and solar urticarias are clinical appearance of urticaria and are generally diagnosed by history of exposure

Tests The diagnosis is usually suspected by the clinical examination and history, and confirmed by one of several simple office test

Tests For dermatographism or physical urticaria a tongue blade or cotton swab stnokod firmly across he forcarm or back produces a linear wheal like lesion within minutes

Tests In pressure urticaria testing with localized pressure points can usually confirm the diagnosis

Tests In cold urticaria, hives are induced with an ice pack or an cube held a sudden drop the skin for 1-5 minutes

Treatment In dermatographism, treatment is often unnecessary Symptomatic dermatographism is treated with antihistamines, such as hydroxyzine and diphenhydramine. The conditions of many patients are controlled for long periods with very low doses of antihistamines. Long-acting, non-sedating antihistamines can also be effective. In cholinergic urticaria, limiting strenuous exercise or administering hydroxyzine prior to exercise can be helpful.

Treatment… In cold urticaria, the patient should be protected from sudden decreases in temperature, and cyproheptadine, another short-acting antihistamine can be effective but sedating. The dosage is adjusted to control symptoms. In solar urticaria, antihistamines can be employed, but sunscreens and vigorous sun avoidance should be recommended. For some patients, small, incremental increases in ultraviolet light may be helpful.

Angioedema Description Angioedema is an acute or chronic hive like swelling in the deeper subcutaneous tissue of the skin and mucosa. Hereditary a is characterized by recurrent episodes of intense edema and swelling in several locations, in those that are genetically predisposed History Hives and angioedema commonly occur simultaneously, but not always. The deeper reaction of angioedema produces a more diffuse swelling, which can be dramatic.

Angioedema History Hives and angioedema commonly occur simultaneously, but not always. The deeper reaction of angioedema produces a more diffuse swelling, which can be dramatic.

Angioedema Itching is usually absent, but burning and painful swelling are typical The lips, palms, soles, limbs, trunk, and genitalia are most commonly affected. Involvement of the gastrointestinal and respiratory tracts produces dysphagia, dyspnea, colicky abdominal pain, and attacks of vomiting and diarrhea.

Type of angiedima There are two forms of the disease: acute and chronic. In acute angioedema, there is a severe allergic type 1 immediate hypersensitivity immunoglobulin E-mediated reaction and is usually selflimited. The etiology of most cases of chronic angioedema is unknown. The condition is most common in 40-50-year-old women

Skin symptoms The reaction is similar to that of hives, but in angioedema, there is also deeper swelling of the subcutaneous tissues of the skin and mucosa. The clinical appearance tends to be more dramatic than typical hives and can cause disfigurement to the point where the patient is unrecognizable. Occasionally, eyes can be swollen shut, oral mucosa can be so edematous that phonation can be affected In hereditary angioedema, the gastrointestinal tract and upper airway can be involved in addition to the skin and mucosa, and be life- threatening

Laboratory and Testing Thyroid microsomal and thyroglobulin antibodies are present in some patients with chronic angioedema. Quantitative and functional analysis of C1 esterase inhibitor and C4 should be performed when hereditary angioedema is suspected.

Treatment Acute severe attacks are treated with Angioedima epinephrine and high dosages of or antihistamines. EpiPen should be considered for patients who experience recurrent severe reactions. Affected patients should wear a medical alert bracelet that identifies the diagnosis and risk. For chronic relapsing courses of the disease, antihistamines such as hydroxyzine can be used quickly to slow reactions. Systemic corticosteroids may be required for suppression in some severe, recalcitrant cases The use of levothyroxine should be considered if patients are hypothyroid.