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Pilonidal Cyst

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A pilonidal cyst occurs at the bottom of the tailbone (coccyx) and can become infected and filled with pus. Once infected, the technical term is pilonidal abscess. Pilonidal abscesses look like a large pimple at the bottom of the tailbone, just above the crack of the buttocks. It is more common in men than in women. It usually happens in young people up into the fourth decade of life.

Pilonidal Cyst Causes

Most doctors think that ingrown hairs cause pilonidal cysts. Pilonidal means "nest of hair." It is common to find hair follicles inside the cyst.

Another theory is that pilonidal cysts appear after trauma to that region of the body. During World War II, more than 80,000 soldiers developed pilonidal cysts that required a hospital stay. People thought the cysts were due to irritation from riding in bumpy Jeeps. For a while, the condition was actually called "Jeep disease."

Pilonidal Cyst Symptoms

The symptoms of a pilonidal cyst include:

  • Pain at the bottom of the spine
  • Swelling at the bottom of the spine
  • Redness at the bottom of the spine
  • Draining pus
  • Fever

When to Seek Medical Care for a Pilonidal Cyst

A pilonidal cyst is an abscess or boil. It needs to be drained, or lanced, to improve. Like other boils, it does not improve with antibiotics. If any of the above symptoms occur, consult a doctor.

Pilonidal Cyst Exams and Tests

A doctor can diagnose a pilonidal cyst by taking a history (asking about the patient's history and symptoms regarding the cyst) and performing a physical exam. The doctor may find the following conditions:

  • Tenderness, redness, and swelling between the cheeks of the buttocks just above the anus
  • Fever
  • Increased white blood cells on a blood sample (not always taken)
  • Inflammation of the surrounding skin

Pilonidal Cyst Home Remedies

Early in an infection of a pilonidal cyst, the redness, swelling, and pain may be minimal. Sitting in a warm tub may decrease the pain and may decrease the chance that the cyst will develop to the point of requiring incision and drainage.

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