Download Aquagenic Urticaria

‫دکتر افشین شیرکانی‬
‫فوق تخصص آسم و آلرژی و بیماری های نقص ایمنی‬
‫عضو آکادمی آسم و آلرژی و ایمونولوژی آمریکا‬
‫استادیار دانشگاه‬
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Urticaria is a type of skin rash, which is
raised, pruritic, erythematous, and transient (
lasts less than 24 hours at the same location),
and is also known as hives
It is the same wheal-and-flare-type skin
reaction as observed in the positive skin prick
test
◦ Acute:< 6 Wks : It occurs in up to 20% of
the population and is often associated
with drug, food, or other allergy, or with
infection
◦ Chronic : > 6Wks : It occurs in about 0.5%
of the population; in about 45% of CIU
patients is an autoimmune disease, due
either to IgG antibody to the α subunit of
the high-affinity IgE receptor or, less
commonly, to anti-IgE antibody
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dilated blood vessels and edema in the
superficial dermis
Angioedema in that the latter occurs in the
deep dermis and subcutaneous tissue
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50% : Urticaria + Angioedema
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40% : Only Urticaria
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10% : Only Angioedema
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Multiple vasoactive mediators are released
after the binding of antigen to IgE on
basophiles or tissue mast cells
Mast cell: histamine, prostaglandin D,
leukotrienes LTC4 and LTD4, and PAF
Complement system: anaphylatoxins C3a,
C4a, and C5a; also histamine
Hageman factor-dependent pathway:
bradykinin
Mononuclear cells: histamine-releasing
factors and chemokines
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Infections: bacterial (Helicobacter pylori)
Transfusion reactions
Chronic idiopathic urticaria
Hereditary urticaria, such as familial cold urticaria
and amyloidosis, with deafness and urticaria (eg.
Muckle-Wells syndrome)
Inhalation or contact with allergens
NSAIDs and/or drug reactions and neoplasms such as
Schnitzler’s syndrome
Gut: foods or food additives
Mastocytosis (systemic): Urticaria pigmentosa
Autoimmune urticaria
Physical urticarias: different types
Systemic lupus erythematosus, carcinoma, and other
collagen vascular diseases
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Cold Urticaria
Urticaria occurs on cold-exposed areas of the
body
Systemic reactions can occur with shock
(patient should avoid swimming in lakes)
Drug of choice classically is cyproheptadine
(C for cold); other antihistamines also work
Idiopathic cold urticaria (most common),
induced by histamine after cold exposure;
could be antibody-mediated and passively
transferred; IgE, IgG, and IgM.
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Cholinergic Urticaria and Local Heat Urticaria
Pruritic, small macules, and papules occur in
response to heat, exercise, or emotional
stress
Occurs primarily in teenagers and young
adults
Autologous sweat sensitivity: sweat may
cause basophil degranulation in sensitive
subjects who have positive skin test to own
sweat
Drug of choice: Hydroxyzine (H for heat).
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Dermatographism
Very common; affects 2%-5% of population.
Stroking of the skin results in linear wheals,
which may persist as long as 30 minutes.
Passive transfer studies suggest an IgEmediated reaction.
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Solar Urticaria
Rare, brief exposure to light causes urticaria
within one to three minutes; most affected
patients are in third and fourth decade of life.
Type I and IV may be passively transferred
(possibly due to IgE).
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Aquagenic Urticaria
Small wheals result from contact with water,
independent of temperature.
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exclusion after ruling out acute urticaria and physical
urticarias; identifiable etiologies may be found in less
than 2% of cases(20% physical and 80% Idiopathic)
30%-40% CIU autoimmune cause, IgG or IgM
antibodies against high affinity IgE receptor α-chain,
rarely anti-IgE antibodies
Detected through autologous serum skin test and
basophil histamine release assays.
Thyroid autoantibodies presents in more than 20% of
patients with CIU, where antithyroid peroxidase is
greater than antithyroglobulin antibody.
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Blood Tests
Blood tests are not helpful for acute urticaria.
For chronic urticaria without identified
etiology, limited blood tests may be obtained,
including CBC Diff, ESR, and
antithyroglobulin,U/A,LFT,S/E,CXR,ANA
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Specific Testing Procedures for Physical
Urticaria :
Cold urticaria: ice cube test
Vibratory urticaria: vibration with laboratory
vortex for four minutes
Aquagenic urticaria: challenge with tap water
at various temperatures
Heat urticaria: test tube water at 44C (111F)
Cholinergic urticaria: exercise for 15-20
minutes or leg immersion in 44C (111F) bath
Pressure urticaria: Sandbag test
Dermographism: Stroking with narrow object
(eg, tongue blade and fingernail).
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Elimination of trigger factors
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H1-antihistamines, preferably nonsedating
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And H2-receptor antagonists
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chronic urticaria, low-dose daily or
alternate-day corticosteroids or other
immunomodulators may be needed, such as
leukotriene antagonists, cyclosporine, and
tacrolimus.
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Urticarial Vasculitis (UV) :
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Hypocomplementemic Urticarial Vasculitis Syndrome
(HUVS) :
Skin lesions generally last longer than urticaria and
they tend to be less pruritic. Often described as painful
and burning. Histopathology shows leukocytoclasis and
vessel wall damage. Lesions can resolve with purpura
or hyperpigmentation remaining.
Urticaria with hypocomplementemia. Also associated
with angioedema, obstructive lung disease, uveitis, and
episcleritis. Laboratory findings include ↓C3 or C4,
↓↓C1q, anti-C1q antibodies, and ↑ESR.
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1. Histamine dependent : 90%: EPI-Antihistaminecorticosteroid response
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2. Kallikrein-Kinin : 10%: NO response to above
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Autoactivation of factor XII
Decrease of C4,C1INH,C1q
Loss of function of C1INH
ACE (major enzyme for bradykinin degradation)
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Hereditary angioedema (HAE)
AD
 Deficiency of Cl inhibitor: 85% ( type I)
:decrease C1INH, C4,C2(Attack)
 Dysfunctional Cl-esterase inhibitor:15%
(type II) :Nl C1INH, decrease C4,C2(Attack)
 HAE patients have normal laboratory (Type
III ), Female
 25% of cases occur in patients without any
family history
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Clinical manifestation of HAE
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unpredictable, recurrent attacks of episodic
swelling that involves:
Face
Peripheral extremities
Genitalia
Abdomen
Oropharynx and pharynx
Triggers of HAE
Trauma
Menses
Stress
Fever
Exercise
Surgery
Stinging
Treatment of HAE
HAE attacks:
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Berinert (for acute facial or abdominal attacks in
children ≥13 years old)
Kalbitor (for acute attacks in children ≥16 years
of age)
Cinryze (for prophylaxis in adolescents and adults)
FFP
HAE prophylaxis:
 Androgen (Danasol) , Tranexamic acid,FFP