Urticaria (Hives)
Epidemiology:
Common sites:
- trunk
- distal extremities
- ears
Gross features:
- pruritic edematous papules and plaques (wheals)
- lesions develop
and fade within hours
Histologic features:
- subtle
- sparse superficial
perivenular infiltrate
- mononuclear
- rare neutrophils
- eosinophils maybe
- collagen bundles
more widely spaced
- dilated
superficial lymphatic channels
Immunophenotype:
Marker:
|
Sensitivity:
|
Specificity:
|
|
|
|
Molecular features:
Other features:
- localized mast
cell degranulation
- angioedema is similar but involves subcutaneous
fat
- persistent
episodes may herald underlying disease (minority of cases):
- collagen
vascular disorders
- Hodgkin disease
- Most are IgE dependent
- Some are IgE independent:
- Opiates
- Antibiotics
- Curare
- Contrast media
- Aspirin
- Hereditary angioneurotic edema (complement-mediated urticaria)
References: