Diagnosis: Vasculitis
Description: Palpable purpura and blister
Morphology: Purpura
Site: Leg
Sex: M
Age: 34
Type: Clinical
Submitted By: Ian McColl
Differential DiagnosisHistory: Vasculitis on the lower limbs is characterized by palpable purpura.In severe cases there may be blisters.The vascular damage is usually due to immune complexes deposited in the skin.The immune complexes can come from a variety of sources including infections,drugs ,underlying malignancy and collagen diseases with associated autoimmunity.In this case it was an allergy to tetracycline antibiotics.