Download MBBS Venereology and Leprosy Presentations 5 Urticaria and Angioedema Lecture Notes

--- Content provided by‌ FirstRanker.com ---

&

ANGIOEDEMA

? Urticaria is characterized by transient skin or mucosal

--- Content provided by⁠ FirstRanker.com ---

swellings due to plasma leakage.

? Superficial dermal swellings are wheals
? Deep swellings of the skin or mucosa are angioedema

--- Content provided by⁠ FirstRanker.com ---

WHEALS

? Pruritic, pink/ red/pale

--- Content provided by FirstRanker.com ---

swellings of the superficial

dermis

--- Content provided by​ FirstRanker.com ---

? ? Initial flare
? Few millimeters to several

centimeters

--- Content provided by‌ FirstRanker.com ---

? Number: few to numerous.
? Hallmark : individual lesions

come and go rapidly, by

--- Content provided by‌ FirstRanker.com ---

definition, in general within 24

hours.

ANGIOEDEMA

--- Content provided by​ FirstRanker.com ---

? Swellings occur deeper in the

dermis/subcutaneous/submucosal

--- Content provided by FirstRanker.com ---

tissue.

? May affect the mouth rarely, the

bowel.

--- Content provided by‍ FirstRanker.com ---

? Involved areas : normal or faint

pink in color, rather than red

--- Content provided by FirstRanker.com ---

? Painful rather than itchy,
? Larger and less well defined than

wheals

--- Content provided by‍ FirstRanker.com ---

? Often last for 2 to 3 days


1. Classic immediate

--- Content provided by FirstRanker.com ---

hypersensitivity binding of

receptor-bound specific IgE by

allergen.

--- Content provided by FirstRanker.com ---

? Others: stimuli that act through

the IgE receptor

2. anti-IgE and

--- Content provided by​ FirstRanker.com ---

3. anti-FcRI antibodies
4. Non-immunologic stimuli:
opiates, C5a anaphylatoxin, stem

cell factor,some neuropeptides(e.g.

--- Content provided by FirstRanker.com ---

substance P)
? cause mast cell degranulation by

binding specific receptors,

--- Content provided by‍ FirstRanker.com ---

independent of the FcRI


PATHOGENESIS

--- Content provided by⁠ FirstRanker.com ---

? The mast cell is the primary effector cell of urticaria.
? Degranulation:
1. Cross-linking of two or more adjacent FcRI on the mast cell

--- Content provided by​ FirstRanker.com ---

membrane

2. initiate a chain of calcium- and energy-dependent steps
3. fusion of storage granules with the cell membrane and

--- Content provided by‌ FirstRanker.com ---

externalization of their contents.
PATHOGENESIS

? Basic pathology - capillary permeability, allowing proteins and

--- Content provided by FirstRanker.com ---

fluids to extravasate to the dermis.

1. Histamine and other proinflammatory mediators released on

degranulation ?

--- Content provided by FirstRanker.com ---

Bind receptors on postcapillary venules in the skin ?
Vasodilation and increased permeability to large plasma proteins

(albumin and immunoglobulins).

--- Content provided by‌ FirstRanker.com ---

2. Histamine, TNF- and IL-8 upregulate adhesion molecules on

endothelial cells, promoting the migration of inflammatory cells

into the urticarial lesion.

--- Content provided by FirstRanker.com ---

CLINICAL CLASSIFICATION OF

URTICARIA AND ANGIOEDEMA

--- Content provided by​ FirstRanker.com ---

1. "Ordinary" (spontaneous) urticaria
2. Physical (inducible) urticarias
3. Urticarial vasculitis (vasculitis on skin biopsy)
4. Contact urticaria (induced by percutaneous or

--- Content provided by​ FirstRanker.com ---

mucosal penetration)

5. Angioedema without wheals
6. Distinctive urticarial syndromes

--- Content provided by​ FirstRanker.com ---

ACUTE vs CHRONIC URTICARIA

? All urticarias are acute initially
? "Chronic urticaria": usually defined as 6 weeks or more.

--- Content provided by‍ FirstRanker.com ---

Applied to continuous urticaria occurring at least twice

a week off treatment for 6 weeks

--- Content provided by FirstRanker.com ---

? Urticaria occurring 6 weeks is called episodic / recurrent


ASSOCIATIONS OF CHRONIC URTICARIA

--- Content provided by⁠ FirstRanker.com ---

? Autoimmune thyroid disorders
? Vitiligo
? Insulin dependent diabetes
? Rheumatoid arthritis
? Pernicious anemia

--- Content provided by FirstRanker.com ---

? Helicobacter pylori gastritis
? Intestinal strongyloidiasis(endemic countries)
? ?Dental infections or gastrointestinal candidiasis

--- Content provided by⁠ FirstRanker.com ---

CLASSIFICATION OF PHYSICAL

URTICARIA

--- Content provided by FirstRanker.com ---

CLASSIFICATION OF PHYSICAL

URTICARIA

--- Content provided by FirstRanker.com ---

CLASSIFICATION OF PHYSICAL

URTICARIA

--- Content provided by‍ FirstRanker.com ---

URTICARIAL VASCULITIS

1. Favors middle-aged women
2. Urticarial lesions >24 hours in duration;

--- Content provided by‍ FirstRanker.com ---

painful & burning sensation as well as

pruritus;

3. Residual purpura as they resolve

--- Content provided by‌ FirstRanker.com ---

4. Sites: often occur at pressure points
5. Concurrent angioedema :up to 40% of pts
6. Disease course: average of 3 years
EXTRACUTANEOUS MANIFESTATIONS

--- Content provided by‍ FirstRanker.com ---

OF URTICARIAL VASCULITIS

1. Arthralgias (50%) ? transient, migratory
2. GI (20%) ? abdominal pain, nausea, vomiting, diarrhea
3. Pulmonary obstructive disease (20%)

--- Content provided by FirstRanker.com ---

4. Renal (5?10%) ? proteinuria, hematuria
5. Ocular (unusual) ? conjunctivitis, episcleritis, uveitis
6. Others - Raynaud's phenomenon, livedo reticularis, splenomegaly,
lymphadenopathy, idiopathic intracranial HTN, pericardial or

--- Content provided by FirstRanker.com ---

muscle involvement

ASSOCIATED DISORDERS OF

URTICARIAL VASCULITIS

--- Content provided by‍ FirstRanker.com ---

? Systemic lupus erythematosus
? Sj?gren's syndrome
? Serum sickness
? Cryoglobulinemia

--- Content provided by​ FirstRanker.com ---

? Infections ? hepatitis B or C virus, Epstein-Barr virus
? Rarely, solar or cold urticaria, drugs, hypergammaglobulinemia
CONTACT URTICARIA

? Development of urticaria at the site(s) of contact of urticant

--- Content provided by‍ FirstRanker.com ---

with skin or mucosa

? Percutaneous or mucosal penetration of the urticant may have

--- Content provided by‌ FirstRanker.com ---

distant effects, including acute urticaria or even anaphylaxis

? Immunologic and non-immunologic forms are recognized

CONTACT URTICARIA

--- Content provided by⁠ FirstRanker.com ---

? Immunologic: sensitized to environmental allergens (grass, animals

and foods) or in glove-wearers (latex).

--- Content provided by​ FirstRanker.com ---

? Non immunologic:

? Percutaneous microinjection of vasomediators

(histamine,acetylcholine, serotonin) via nettle stings

--- Content provided by FirstRanker.com ---

? contact with histamine liberators that degranulate mast cells

(dimethylsulfoxide,cobalt chloride)
FOOD CONTACT

--- Content provided by‌ FirstRanker.com ---

HYPERSENSITIVITY SYNDROME

? Itching and mild swelling of the mouth, tongue

--- Content provided by‌ FirstRanker.com ---

and soft palate within minutes of eating fresh

fruits but not cooked fruit

? apples, pears, peaches and cherries,

--- Content provided by FirstRanker.com ---

DIAGNOSIS

? Comprehensive history
? Duration of individual lesions, presence of purpura

--- Content provided by‍ FirstRanker.com ---

? Weals lasting more than 24?48 h, particularly if

painful or tender, suggest urticarial vasculitis

? Frequency of attacks, duration of disease, previous

--- Content provided by‍ FirstRanker.com ---

treatment, known triggers

? Past and family history,
? Occupation and leisure activities,

--- Content provided by⁠ FirstRanker.com ---

DIAGNOSIS

? Assessment of the impact of the disease on the patient's

--- Content provided by‌ FirstRanker.com ---

quality of life.

? Asso. angiooedema (eg. Oropharynx result in difficulty in

--- Content provided by⁠ FirstRanker.com ---

swallowing or breathing)

? Systemic symptoms
? Recent acute infection, drugs, nonprescription and

--- Content provided by​ FirstRanker.com ---

prescription medicines, food
INVESTIGATIONS

? Rule out Infections
? Complete blood count

--- Content provided by FirstRanker.com ---

? Stool for ova, cysts and parasites
? Thyroid autoab, Thyroid function tests
? C4 complement (angiooedema without weals)
? Nonorgan specific autoantibodies (eg ANA)
? Basophil histamine release assay / basophil activation tests

--- Content provided by‍ FirstRanker.com ---

? Helicobacter pylori (stool antigen or urea breath test)
? Chest Xray
? 25hydroxycholecalciferol (vitamin D)

TREATMENT

--- Content provided by⁠ FirstRanker.com ---

? Detection and avoidance of the cause.
? First line therapies (H1 antihistamines)

minimal dosing which control episodes.

--- Content provided by⁠ FirstRanker.com ---

H1 ? non sedating day time, sedating at night.

--- Content provided by‌ FirstRanker.com ---

A combination of an H1 antihistamine with
an H2 antagonist may be more effective than

--- Content provided by‍ FirstRanker.com ---

H1 antihistamines alone in some patients

--- Content provided by​ FirstRanker.com ---

TREATMENT

Second line therapies (targeted therapy)
? Oral corticosteroids
? Leukotriene receptor antagonists

--- Content provided by‌ FirstRanker.com ---

? Doxepin,
? Danazol
? Sulphasalazine and dapsone

--- Content provided by FirstRanker.com ---

THANK YOU