Petechiae

Definition

Petechiae are small, pinpoint red or purple spots on the skin caused by minor bleeding from broken capillaries. They can be a sign of various underlying conditions, including infections affecting the circulatory and lymphatic systems.

5 Must Know Facts For Your Next Test

1. Petechiae often indicate a low platelet count (thrombocytopenia) or clotting disorder.
2. Common causes of petechiae include viral infections like dengue fever, bacterial infections such as meningococcemia, and certain medications.
3. The presence of petechiae can help differentiate between different types of rashes in clinical diagnoses.
4. Petechiae do not blanch (turn white) when pressed, unlike some other types of skin rashes.
5. In the context of sepsis, petechiae can signify disseminated intravascular coagulation (DIC), a severe condition requiring immediate medical attention.

Review Questions

• What are petechiae and what do they indicate?
• How can petechiae be used to differentiate between types of rashes?
• What is the significance of non-blanching in diagnosing petechiae?

Related terms

Thrombocytopenia: A condition characterized by an abnormally low number of platelets in the blood.

Meningococcemia: A bloodstream infection caused by Neisseria meningitidis bacteria.

Disseminated Intravascular Coagulation (DIC): A serious disorder involving widespread clotting and bleeding throughout the body.