Purpura
August 13th, 2017
Overview
Purpura, or bruising, may develop in the context of trauma, coagulopathy, platelet deficiency / dysfunction, or vascular disorders.
Look For
- Red / purple lesions that do not blanch with pressure. May be present over the head, arms, legs, chest or abdomen.
Interpretation
- Petechiae - flat lesions, <4mmThrombocytopaenia / abnormal platelet function, DIC
- Ecchymoses - flat lesions, >4mmTrauma, DIC, coagulation disorders, senile purpura
- Palpable purpura associated with arthralgia, abdominal pain and renal diseaseHenoch-Schönlein purpura
Causes of Purpura
Trauma
Platelet Disorders
- Idiopathic thrombocytopaenic purpura (ITP)
- Thrombotic thrombocytopaenic purpura (TTP)
- Disseminated intravascular coagulation (DIC)
- Bone marrow failure - aplastic anaemia, leukaemia, chemotherapy
- Platelet sequestration - splenomegaly, haemangioma
- Haemolytic-uraemic syndrome
Disorders of Coagulation
- Factor deficiencies - haemophilia, Von Willebrand disease
- Vitamin K deficiency - malabsorption, poor diet
- Anticoagulants
Vascular Disorders
- Connective tissue diseases - Ehlers-Danlos, scurvy
- Infection - mengingococcal, streptococcal, viral
- Henoch-Schönlein purpura
- Senile purpura
- Steroids
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------