Causes Purpura has various causes. Senile purpura, found in older people, appears to be related to excessive exposure to the sun. Another form of purpura is caused by vitamin C deficiency. Incidence Allergic purpura mainly affects children two to six years old, but it is a rare disease. Purpura simplex is more common among women than men.
Senile purpura affects older people and is more common among men than women.
Thrombocytopenic purpura is usually a side effect of cancer therapy or of prescription drugs but can appear as a symptom in leukemia or other blood disorders. Symptoms you are likely to notice Purplish or reddish discolorations appear in the area of subcutaneous bleeding. Purpura simplex bruises appear most often on the upper arms, thighs, and buttocks. One way to recognize purpura in children is to press the base of a clear drinking glass against the rash. If the discoloration can still be seen through the glass, it is probably purpura and not some other rash.