Pilonidal cyst

A pilonidal (pie-low-NIE-dul) cyst is an abnormal pocket in the skin that usually contains hair and skin debris. A pilonidal cyst is almost always located near the tailbone at the top of the cleft of the buttocks.

These cysts typically occur when hair punctures the skin and then becomes embedded. If a pilonidal cyst becomes infected, the resulting abscess is often extremely painful. The cyst can be drained through a small incision or removed surgically.

Pilonidal cysts most commonly occur in young men, and the problem has a tendency to recur. People who sit for prolonged periods of time, such as truck drivers, are at higher risk of developing a pilonidal cyst.

Symptoms Causes Risk factors Complications Prevention

When it's infected, a pilonidal cyst becomes a swollen mass (abscess). Signs and symptoms of an infected pilonidal cyst include:

  • Pain
  • Reddening of the skin
  • Drainage of pus or blood from an opening in the skin
  • Foul smell from draining pus

When to see a doctor

If you notice any signs or symptoms of a pilonidal cyst, see your doctor. He or she can diagnose the condition by examining the lesion.

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