What are the causes of purpura?
Purpura may occur when the platelet count of the blood is low (thrombocytopenia) but there are other causes too. It can occur when the blood vessel wall is particularly fragile, has been damaged, or if the skin is thin. In elderly people so-called ‘senile purpura’ is often seen on the outer surface of the arm and back of the hand. Similar features are seen in some patients treated with long-term steroid therapy because steroids weaken the connective tissues of the skin. In some inflammatory conditions damage to the vessel wall, or ‘vasculitis’, may occur and can cause purpura. An example is the inflammatory disorder in children known as Henoch Schönlein purpura. In this there is abdominal pain, joint pain, kidney inflammation and raised purpura typically over the buttocks and limbs. Purpura with painful bruising of the legs and around hair roots may also be seen in vitamin C deficiency or scurvy. Purpura should be reported to a doctor for further investigation. In a person who is other
