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Pilonidal Cyst

A pilonidal cyst is a closed sac under the skin at the top of the crease of the buttocks. Pilonidal cysts usually do not cause problems unless they become infected.

The cause of a pilonidal cyst is unclear. They usually occur in men in their late teens through 20s, although they are occasionally noticed at birth as a depression or sometimes as a hairy dimple.

Symptoms of an infected pilonidal cyst (abscess) include:

  • Pain.
  • Swelling and redness.
  • Drainage of pus and/or blood.
  • Fever.

If a pilonidal cyst develops a long-lasting or frequently recurring infection, it is called pilonidal disease. Treatment includes surgical drainage or surgical removal.

ByHealthwise Staff
Primary Medical ReviewerAnne C. Poinier, MD - Internal Medicine
Specialist Medical ReviewerC. Dale Mercer, MD, FRCSC, FACS - General Surgery
Last RevisedNovember 15, 2011

WebMD Medical Reference from Healthwise

Last Updated: November 15, 2011
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