Purpura


Multimedia

Definition

Purpura is purple-colored spots and patches that occur on the skin, organs, and in mucus membranes, including the lining of the mouth.


Alternative Names

Blood spots; Skin hemorrhages


Considerations

Purpura occurs when small blood vessels join together or leak blood under the skin.

When purpura spots are very small, they are called petechiae. Large purpura are called ecchymoses.

Platelets help the blood clot. A person with purpura may have normal platelet counts (nonthrombocytopenic purpuras) or low platelet counts (thrombocytopenic purpuras).


Common Causes

Nonthrombocytopenic purpuras may be due to:

  • Amyloidosis
  • Blood clotting disorders
  • Congenital cytomegalovirus
  • Congenital rubella syndrome
  • Drugs that affect platelet function
  • Fragile blood vessels (senile purpura)
  • Hemangioma
  • Inflammation of the blood vessels (vasculitis), such as Henoch-Schonlein purpura, which causes a raised type of purpura
  • Pressure changes that occur during vaginal childbirth
  • Scurvy
  • Steroid use

Thrombocytopenic purpura may be due to:

  • Drugs that prevent platelets from forming
  • Idiopathic thrombocytopenic purpura (ITP)
  • Immune neonatal thrombocytopenia (can occur in infants whose mothers have ITP)
  • Meningococcemia -- a raised type of purpura

References

Korman NJ. Macular, papular, vesicobullous, and pustular diseases. In: Goldman L, Ausiello D. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 465.

Coller BS, Schneidermann PI. Clinical evaluation of hemorrhagic disorders: the bleeding history and differential diagnosis of purpura. In: Hoffman R, Benz EJ, Shattil SS, et al. Hematology: Basic Principles and Practice. 5th ed. Philadelphia, Pa: Churchill Livingstone; 2008: chap 121.


Request An Appointment

Review Date: 5/20/2011
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2004 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

adam.com
Last Updated 2/21/2012
Find a Doctor

e.g., "allergy," "diabetes"

US News Best Hospital AwardANCC Magnet Association AwardBest Doctors 2011-2012 AwardConsumer Choice #1 Award 2011-2102US News Best Medical Schools 2011 Award

Disclaimer: The information on this website is for general informational purposes only and SHOULD NOT be relied upon as a substitute for sound professional medical advice, evaluation or care from your physician or other qualified health care provider.