petechia

medicine

Also known as: petechiae

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Last updated

July 1, 2026

Quick Summary

Petechia are minute, reddish or purplish spots that appear on the skin or mucous membranes. These spots are caused by localized hemorrhages, meaning small bleeds under the skin.1

Petechiae are often a symptom of thrombocytopenia, a condition characterized by an abnormally low number of platelets in the blood. Platelets are essential for blood clotting, and a deficiency can lead to spontaneous bleeding. When platelet counts are very low, tiny purplish spots (petechiae) or larger bruises (ecchymoses) may appear on the skin. Other symptoms can include nosebleeds, easy bruising, and more severe bleeding.2

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

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- cardiovascular disease
  Diseases of the capillaries
  …hemorrhages are referred to as petechiae when small; if large, they may become a large area of discoloration of the skin. Vitamin C deficiency and a variety of blood disorders may be associated with increased capillary fragility. Small petechial hemorrhages occur in bacterial endocarditis and certain other infectious processes. In…
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  …hemorrhages are referred to as petechiae when small; if large, they may become a large area of discoloration of the skin. Vitamin C deficiency and a variety of blood disorders may be associated with increased capillary fragility. Small petechial hemorrhages occur in bacterial endocarditis and certain other infectious processes. In…
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meningitis
Course of the disease
…develop into hemorrhagic spots (petechiae and purpura) in severe cases. In the third stage, the bacteria multiply in the meninges, where they produce intense inflammatory changes and an exudate of pus.
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…develop into hemorrhagic spots (petechiae and purpura) in severe cases. In the third stage, the bacteria multiply in the meninges, where they produce intense inflammatory changes and an exudate of pus.
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