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EntityQ935293· pop 30· linked from 370 articles

Also known as petechial rash, purpuric disorder

Purpura () is a condition of red or purple discolored spots on the skin that do not blanch on applying pressure. The spots are caused by bleeding underneath the skin secondary to platelet disorders, vascular disorders, coagulation disorders, or other causes. They measure 3–10 mm, whereas petechiae measure less than 3 mm, and ecchymoses greater than 1 cm.

Key facts

Medical condition (new).name
Purpura
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HSP Vasculitis.jpg
Medical condition (new).caption
Petechiae and purpura on the lower limb due to infection-associated vasculitis
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Dermatology, hematology

via Wikipedia infobox

Research

41,851 papers

via PubMed

~3 min read

Encyclopedic overview

5 sections
Contents
  • Classification
  • Etymology and pronunciation
  • See also
  • References
  • External links

Purpura () is a condition of red or purple discolored spots on the skin that do not blanch on applying pressure. The spots are caused by bleeding underneath the skin secondary to platelet disorders, vascular disorders, coagulation disorders, or other causes. They measure 3–10 mm, whereas petechiae measure less than 3 mm, and ecchymoses greater than 1 cm.

Purpura is common with typhus and can be present with meningitis caused by meningococci or septicaemia. In particular, meningococcus (Neisseria meningitidis), a Gram-negative diplococcus organism, releases endotoxin when it lyses. Endotoxin activates the Hageman factor (clotting factor XII), which causes disseminated intravascular coagulation (DIC). The DIC is what appears as a rash on the affected individual.

Excerpted from Wikipedia’s “purpura” article, available under the CC BY-SA 4.0 licence.