Purpura Depending on their size, purpuric lesions are traditionally classified as petechiae (pinpoint hemorrhages less than 2 mm in greatest diameter), purpura (2 mm to 1 cm) or ecchymoses (more than 1 cm). HP:0000979 Purpura (from Latin: purpura, meaning purple) is the appearance of red or purple discolorations on the skin that do not blanch on applying pressure. They are caused by bleeding underneath the skin. This term refers to an abnormally increased susceptibility to developing purpura. Purpura are larger than petechiae. SNOMEDCT_US:387778001 SNOMEDCT_US:12393003 SNOMEDCT_US:423902002 Red or purple spots on the skin UMLS:C0034150 Blood spots Subcutaneous hemorrhage