Pilonidal disease is a condition that can occur anywhere along the crease between the buttocks, which runs from the bone at the bottom of the spine (sacrum) to the anus.

Pilonidal disease may appear as:

• A pilonidal abscess, in which the hair follicle becomes infected and pus collects in the fat tissue
• A pilonidal cyst, in which a cyst or hole forms if there has been an abscess for a long time
• A pilonidal sinus, in which a tract grows under the skin or deeper from the hair follicle
• A small pit or pore in the skin that contains dark spots or hair

Pilonidal abscess; Pilonidal sinus; Pilonidal cyst

Symptoms may include:

• Pus may drain to a small pit in the skin
• Tenderness over the area after you are active or sit for a period of time
• Warm, tender, swollen area near the tailbone

The cause of pilonidal disease is not clear. It is thought to be caused by hair growing into the skin in the crease between the buttocks.

This problem is more likely to occur in people who:

• Are obese
• Experienced trauma or irritation in the area
• Have excess body hair
• Sit for long periods of time
• Wear tight clothing

Images

Pilonidal cyst and dimple

Anatomical landmarks, back view

Next Section

Pilonidal disease Treatment

Review Date: 12/17/2010
Reviewed By: Kevin Berman, MD, PhD, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)