Urticaria

The following is a precise description about urticaria & angioedema from dermatology

1. URTICARIA & ANGIOEDEMA MUHAMMED JASIL

2. Urticaria : irregularly shaped wheal with a blanched center surrounded by a red flare Itchy raised rash Rapid disappearance to normal skin in 1-24 hrs WHEALS: 1)Evanescent 2) Edematous plaque 3)Central pallor, peripheral erythema

3. ETIOLOGY ACUTE : DRUGS: b lactam antibiotics, sulfonamides , aspirin FOOD: milk, egg, peanut, fish, wheat INFECTIONS INSECT BITES & STING CONTACTANTS & INHALANTS

4. CHRONIC : PHYSICAL FACTORS: cold, heat, dermatographic , pressure, solar IDIOPATHIC AUTOIMMUNE VASCULITIC INFECTIOUS

5. INFECTIONS VIRAL: HS, Hep B BACTERIAL: PARASITIC: Ascaris , fasciola , filarial, Schistosoma FUNGAL: Candida

6. PHYSICAL URTICARIA:PRESSURE Large, painful or itchy red swellings @ sites of pressure(soles, palm or waist) Lasting 24 hrs or more Application of pressure perpendicular to the skin produces red swelling after 1-4 hrs

7. DERMOGRAPHIC URTICARIA Itchy, linear wheals with surrounding bright red flare @ sites of scratching or rubbing Most frequent form of physical urticaria Affecting mainly young adults

8. PHYSICAL URTICARIA:COLD Erythematous edematous deep swellings @ the sites of contact with cold surfaces or fluids (9-18hrs after) Acquired & inherited forms Acquired 1º & 2º 1º- idiopathic 2º-circulating cryoglobulins , cryofibrinogens , cold agglutinins & cold hemolysins Inherited-autosomal dominant, erythematous macules & infrequent wheals

9. PHYSICAL URTICARIA:LOCAL HEAT A rare form of urticarial Induced by direct contact of the skin with warm objects or warm air 38°C-50ºC

10. PHYSICAL URTICARIA:SOLAR Develop within minutes after exposure to sun Usually idiopathic May be associated with SLE, Polymorphic light eruption

11. VIBRATORY URTICARIA After several yrs of occupational exp to vibration Autosomal dominant Assc with cholinergic urticaria Typical symptom is hives across the back when towelling off after a shower

12. PHYSICAL URTICARIA:CHOLINERGIC Itchy, monomorphic pale or pink wheals on the trunk, neck & limbs after exercise or a hot shower Anything that rises the internal body temperature

13. ADRENERGIC URTICARIA Wheals surrounded by a white halo Develop during emotional stress Elicited using the IC inj of NE

14. CONTACT URTICARIA Direct contact with a variety of substances IgE mediated or non immunologic Proteins from latex : MC cause of IgE mediated

15. AQUAGENIC URTICARIA Pruritus alone or more rarely urticaria Water of any temp Reminiscent of cholinergic urticaria

16. DIAGNOSIS Thorough history Physical examination Routine diagnostic tests Autologous serum skin test Basophil histamine release assay

17. Rx: Identification & elimination of underlying cause or trigger Symptomatic pharmacological treatment Induction of tolerance

18. DD-URTICARIA URTICARIA PIGMENTOSA URTICARIA VASCULITIS ERYTHEMA MULTIFORME IMMUNOBULLOUS DISEASE-BP COLLAGEN VASCULAR DISEASE ANNULAR ERYTHEMA JUVENILE RHEMATOID ARTHRITIS KAWASAKI DISEASE VIRAL EXANTHEMS SCABIES

19. Angioedema : vascular reaction involving the deep dermis, sub cutaneous or sub mucosal tissues caused by dilatation & increased permeability of capillaries Sites: eyelids, lips, tongue, genitalia, hands, feet & larynx Gi & urinary bladder being less commonly involved pain> itchy Recover slowly (72hrs)

20. TYPES HEREDITARY ACQUIRED

21. Rx No regular medication needed in many caese Prophylactic stanozolol or danozolol Fresh frozen plasma before emergency surgery C1 inhibitor Symptomatic treatment during attacks

22. DD-ANGIOEDEMA CHF LYMPHEDEMA THROMBOPHLEBITIS ERYSIPELAS CELLULITIS NEPHROTIC SYNDROME SVC SYNDROME SCLERODERMA DERMATOMYOSITIS CROHN’S DISEASE