Urticaria lecture

1. URTICARIA
AND
ANGIOEDEMA
SUPERVISED BY
DR / Bassam Al─Drassi

2. URTICARIA AND ANGIOEDEMA
 Urticaria is composed of wheals (transient edematous papules and
plaques, usually pruritic and caused by edema of the papillary body), The
wheals are superficial and well defined.
 Angioedema is a larger edematous area that involves the dermis and
subcutaneous tissue and is deep and ill defined.
 Urticaria and angioedema are thus the same edematous process but
involve different levels of the cutaneous vascular plexus: papillary and
deep.
 Urticaria and/or angioedema may be acute recurrent or chronic recurrent.
Definition
 Is avascular reaction of the skin it is a common skin disease characterized by
wheals(red or white) associated with the sensations of itching or burning .

3.  Incidence : 15-23% of the population
may have had this condition during their
lifetime.
 Urticaria/angioedema is not a disease
but a cutaneous reaction pattern
Epidemiology
URTICARIA AND ANGIOEDEMA

4. Immunologic
lgE-medlated urticarial
Complement-mediated
urticaria
Autoimmune urticaria
Immune contact urticaria
Physical
Dermographism
Cold urticaria
Solar urticaria
Cholinergic urticaria
Pressure angioedema
VIbratory angioedema
Classification
Urticaria due to mast cell-
releasing agents
Pseudoallergens
ACE Inhibitors
Nonimmune contact
urticaria
Idiopathic urticaria
Urticaria associated with
vascular / connective
tissue autoimmune
disease

5.  Urticaria is mediated through immune (allergic) or nonimmune mechanisms.
 Lesions result from the release from mast cells of biologically active
substances, particularly histamine, which produce vasodilatation and
increased vascular permeability.
 Several pathways are recognized:
 IgE-mediated (type I) hypersensitivity is the best understood mechanism;
antigen cross-links immunoglobulin (Ig) E molecules on the surface of mast
cells, resulting in degranulation with release of vasoactive agents.
 Complement activation can produce dermal oedema, as in hereditary
angioedema or urticaria associated with circulating immune complexes.
 Direct release of histamine from mast cells, in a nonimmune manner, is
caused by some drugs, e.g. opiates and contrast media.
 Blocking of the prostaglandin pathway from arachidonic acid, by some drugs
such as aspirin and non-steroidal anti-inflammatory agents, promotes urticaria
by accumulating vasoactive leukotrienes.
Pathogenesis
URTICARIA AND ANGIOEDEMA

6. 1. Drugs: are the most frequent cause of acute urticaria, penicillin & related antibiotics are the
most frequent offenders.
Urticaria reaction can occur 14 days after course of treatment has stopped.
Non allergic release of Histamine by (asprin, NSAIDs, opiates, polymyxin,ciprofloxacin,
rifampicin, vancomycin).
2. food: are a frequent cause of acute urticaria where as in chronic urticaria is less frequent
factor.
The most allergic foods are chocolate, shellfish, nuts, peanuts, tomatoes, strawberries,
melons, cheese, garlic, onions, eggs, milk, and spices.
3. Food additives:
natural food addictives
synthetic additives
Etiological factors
URTICARIA AND ANGIOEDEMA

7. 4. Infections"acute urticaria may be associated with upper respiratory tract infections,
especially streptococcal infections .
Localized infections in tonsils, tooth, sinuses, prostate, urinary bladder and kidney
."Chronic viral infections such as hepatitis B & C"
Helimenthes may cause urticaria these are (ascaris, ankylostomas, strangyloids,
filarial, echinococcus schistosoma & liver flukes
5. Emotional stress:Persons under sever emotional stress may have more marked
urticana.
6. Menthol: It is found in mentholated cigarettes, candy, cough drops, aerosol sprays &
topicalmedications.
7.Neoplasms:Urticana has been associated with carcinoma & Hodgkin's diseases .
URTICARIA AND ANGIOEDEMA
Etiological factors

8. 8. Inhalants:Grass pollens, house dust mites , formaldehyde .
9. Alcohol:The mechanisms of indirect mast cell stimulation are unknown.
10. Hormonal causes:-
Endocrine tumors
Ovarian pathology
Oral contraceptive use
11. Physical causes (physical urticaria):Cold, pressure, vibration, cholinergic (triggered
by heat, exercise or emotional stress), sunlight, water, exercise.
Etiological factors
URTICARIA AND ANGIOEDEMA

9. Clinical manifestation
Skin lesion
Sharply defined wheals , small <1cm to large
>8cm, erythematous or white with an
erythematous rim, round, oval, , annular,
serpiginous caused by confluence and
resolution in one area and progresslon In
another .
Iesions are pruritic and transient.

10. Angioedema
skin colored, transient enlargement of portion
of face (eyelids, Ups, or tongue ) and Drug
induced angioedema extremity, or other sites
resulting from subcutaneous edema.
Clinical manifestation
Diatribation
Usually regional or generalized.
Locallzed in solar, pressure, vibration and
cold urticaria/angioedema and contined to the
site of the trigger mechanism .

11. Clinical types
Evolves over days to weeks < 6 w .
Acute onset and recurring over <30 days .
Usually large wheals are often associated with
angioedema often IgE dependent with atopic
diathesis related to foods, parasites, and
penicillin.
Also, complement mediated in serum sickness
like reactions (whole blood Immunoglobulins
and penicillin).
ACUTE URTICARIA

12. Urticaria and / or angioedema alasting more than
6 weeks
Recurring over > 30 days.
Small and latge wheals .
Rarly IgE ddependent.
Etiology unknown In 80% and therefore
oonsidered idiopathic.
Chronic idiopathic urticaria affects adults
predominantly and is approximately twice as
common in women as In men.
Up to 40% of patients with chronic urticaria of >6
months' duration still have urticaria 10 years later.
Clinical types
CHEONIC URTICARIA

13. SPECIAL
FEATURES/AS
RELATED
TO
PATHOGENESIS
IgE Medlated
Lesions in acute IgE-mediated urticaria result from antigen
induced release of biologically active molecules from mast cells .
Released mediators increase venular permeability and modulate
the release of biologically active molecules from other cell types.
Often with atopic baclcground.
Antigens: food (milk. eggs. wheat. shellfish, nuts),therapeutic
agents, drugs.
Immunologic Urticaria
Complement Mediated
Acute urticarial .
By way of immune complexes activating
complement and releasing anaphylatoxins that
induce mast cell degranulation.
Serum sickness, administration of whole blood
and immunoglobulins.

14. SPECIAL
FEATURES/AS
RELATED
TO
PATHOGENESIS
Autoimmune
Common, chronic.
Autoantibodies against IgE.
Positive autologous serum skin test.
Clinically, patients with these autoantibodies .
Immunologic Urticaria
Immunologic Contact Urticaria
Usually in children with atopic dermatitis
sensitized to invironmental allergens (grass and
animals) .

15. SPECIAL
FEATURES/AS
RELATED
TO
PATHOGENESIS
Dermographism
Linear urticarial lesions occur after stroking or
scratching the skin.
They itch and fade in 30 min.
About 4.2% of the normal population have it.
Physical urticaria

16. SPECIAL
FEATURES/AS
RELATED
TO
PATHOGENESIS
Cold Urticaria
Usually in children or young adults .
Urticarial lesions confined to sites exposed to
colcd occurring within minutes after rewarming.
"Ice cube" test (application of an ice cube for a
few minutes to skin) causes wheal.
Physical urticaria

17. SPECIAL
FEATURES/AS
RELATED
TO
PATHOGENESIS
Solar Urticaria
Is a rare allergic reaction to sun
exposure.
The condation causes an itchy
rash or hives that appear on any
skin that has been exposed to sun.
The more skin that is exposed to
sunlight , the more reaction will be.
Histamine is one of the mediators.
Physical urticaria

18. SPECIAL
FEATURES/AS
RELATED
TO
PATHOGENESIS
Cholinergic urticaria
Exercise to the point of sweating provokes typical small,
papular, highly pruritic urticarial lesion .
Occurring within 30 min of vigorous exercise .
May be accompanied by wheezing.
Physical urticaria

19. SPECIAL
FEATURES/AS
RELATED
TO
PATHOGENESIS
Pressure Angioedema
Erythematous swelling induced by
sustained pressure (buttock swelling
when seated, hand swelling after
hammering, foot swelling after walking).
Delayed (30 min to 12 h).
Painful .
May persist for several days, and
interferes with quality of life.
No laboratory abnormalities, fever may
occur.
Physical urticaria

20. SPECIAL
FEATURES/AS
RELATED
TO
PATHOGENESIS
VIbration Angioedema
May be familial (autosomal dominant) or sporadic.
Rare , it is believed to result from histamine release from mast
cells caused by a vibrating stimulus rubbing a towel across the
back produces lesions.
But direct pressure (without movements) does not.
Physical urticaria

21. Pseudoallergens agents
Urticaria/angioedema and even anaphylaxis like symptoms may occur with radio contrast
media and as a consequence of intolerance to salicylatcs, fuod preservatives and additives
(e.g benzo:lc acid and sodium benzoate)
 Also to ACE inhibitors.
Urticaria due to mast cell-releasing agents
Histamine derived from mast cells In the skin is considered the major mediator.
 Caused by direct effects of exogenous urticants penetrating into skin or blood vessels.
 Localized to the site of contact.
 Sorbic acid, benzoic acid in eye solutions and foods.
URTICARIA AND ANGIOEDEMA
Chronic idiopathic urticaria
Nonimmune contact urticaria

22.  Urticarial lesions may be associated with systemic lupus erythematous
and Sjogren syndrome.
 However, in most instances, they represent Urticarial vasculitis
Urticaria associated with vascular/connective tissue autoimmune disease
 Urticarial vasculitis
 Urticarial vasculitis often has an acute onset with widespread urticarial
lesions that are unusual as they persist for more than 24 h and fade
leaving purpura.
 Systemic abnormalities and low complement levels may be found._
URTICARIA AND ANGIOEDEMA

23. Diagnosis
URTICARIA AND ANGIOEDEMA
Questions to be asked to a patient with urticarial:
 Are the Hives associated with any foods or new foods added?
 Is the patient take any regular medication or have any new medicines, ask about
(aspirin, NSAIDs, antibiotics).
 Does the patient have any recent or chronic infections.
 Are the Hives caused by physical stimuli (heat,cold,pressure).
 Does the patient have any chronic medical conditions.
 Is the urticaria associated with substances inhaled.
 Is the urticaria associated with insect bites.

24. Wheals + angioedema
Duration of individual hive
4 h-36 h 24-48 h with either
bruising, severe arthralgia,
fever, C4
30 min to 2 h
History
physical
Stimulus
physical
challenge
Phyaical
urticaria
Course > 6
wk
Course < 6
wk
Consider drugs,
foods, food skin
testing.
Infection(partIculary
inchildren)
Other identifiable
stimulus
Thyroid functionTests
Anti-microsomal antibody
Antithyroglobulin antibody
Autologous skin test
In vttro-antl-lgE receptore
Acute
urticaria /
angioedema
Positive Negative
Chronic
autoimmune
urticaria
Chronic
Idiopathic
urticaria
Skin
biopsy
Positive
Urticarial
vaecutltla
Diagnosis

25. Diagnosis
URTICARIA AND ANGIOEDEMA
LABORATORY EXAMINATIONS
SEROlOGY hcraeS
rof
Hepatitis B-associated antigen .
Assessment of the complement system.
Assessment of specific lgB antibodies .
Serology for lupus and Sjogren syndrome .
HEMATOLOGY
The erythrocyte sedimentation rate (BSR) is often elevated in urticarial vasculitis ,
and there may be hypocomplementemia .
Transient eosinophilia in urticaria from reactions to foods, parasites, and drugs .

26. Diagnosis
URTICARIA AND ANGIOEDEMA
LABORATORY EXAMINATIONS
COMPLEMENT STUDIES
Screening for functional C1 inhibitor in HAE .
ULTRASONOGRAPHY
For early diagnosis of bowel involvement in HAE If abdominal
pain is present, this may indicate edema of the bowel .
PARASITOLOGY
Stool specimen for presence of parasites .

27. Course
URTICARIA AND ANGIOEDEMA
 The course of an urticarial reaction depends on its
cause.
 If the urticaria is allergic, it will continue until the
allergen is removed, tolerated or metabolized.
 Most such patients clear up within a day or two, even if
the allergen is not identified.
 Urticaria may recur if the allergen is met again.

28. Complications
URTICARIA AND ANGIOEDEMA
 Urticaria is normally uncomplicated.
 Although its itch may be enough to interfere with sleep or
daily activities and to lead to depression.
 In acute anaphylactic reactions oedema of the larynx may
lead to asphyxiation.
 Oedema of the trachea bronchial tree may lead to
asthma.

29. TREATMENT
URTICARIA AND ANGIOEDEMA
LEARNING POINTS
 The treatment of choice is to find the cause and eliminate it.
 You can learn more about the cause from the history than
from tests.
 Most patients with hives clear up quickly even if the cause is
not obvious.
 Use antihistamines in relatively high doses.
 Avoid aspirins and systemic steroids in chronic urticaria.
 Do not promise patients that all will be solved by allergy tests.

30. TREATMENT
URTICARIA AND ANGIOEDEMA
 In general, antihistamines are the mainstays of symptomatic treatment .
 Cetirizine 10 mg/day and
 loratadine 10 mg/day, both with half-lives of around 12 h, are useful.
 If necessary, these can be supplemented with shorter acting
antihistamines, e.g. hydroxyzine 10–25 mg up to every 6 h and
acrivastine 8 mg three times daily.
 Alternatively they can be combined with a longer acting antihistamine as
chlorpheniramine 12 mg sustained release tablets every 12 h.

31. TREATMENT
URTICARIA AND ANGIOEDEMA
 H2-blocking antihistamines (e.g. cimetidine) may add a slight benefit if
used in conjunction with an H1 histamine antagonist.
 Chlorpheniramine or diphenhydramine are often used during
pregnancy because of their long record of safety but cetirizine, loratidine
and mizolastine should be avoided.
 A tapering course of systemic corticosteroids may be used, but only
when the cause is known and there are no contraindications

32. Some
types
of
urticaria
and
their
management Cold urticarial
Avoid cold
Protective clothing
Antihistamines
Solar urticarial
Avoid sun exposure
Protective clothing
Sunscreens and sun blocks
Beta-carotene
Antihistamines
Cholinergic urticarial
Avoid heat
Minimize anxiety
Avoid excessive exercise
Anticholinergics
Antihistamines
Tranquillizers
Dermographism
Avoid trauma
Antihistamines
Hereditary angioedema
Avoid trauma
Attenuated androgenic steroids
as prophylaxis
Tracheotomy may be necessary
Hypersensitivity urticarial
Remove caus
Antihistamines (H1 + H2)
Sympathomimetics
Systemic steroids (rarely justified)
Avoid aspirin-containing drugs