Pilonidal Cyst

(Pilonidal Sinus; Pilonidal Abscess)

Pronounced: PIE-low-NIGH-dull sist

Definition

A pilonidal cyst is a fluid-filled developmental defect at the base of the spine.

The terms cyst, sinus, and abscess refer to different stages of the disease process.

  • Cyst—not infected
  • Abscess—pocket of pus
  • Sinus—opening between a cyst or other internal structure and the outside

While the cyst is not serious, it can become infected and should therefore be treated. When a pilonidal cyst gets infected, it forms an abscess, eventually draining pus through a sinus. The abscess causes pain, a foul smell, and drainage.

Pilonidal Cysts

Pilonidal cyst
Copyright © Nucleus Medical Media, Inc.

Causes    TOP

A pilonidal cyst may be congenital or acquired. If congenital, it probably began as a defect that existed when you were born. Sometime later, the defect allowed an infection to develop. If acquired, it may be the enlargement of a simple hair follicle infection or the result of a hair penetrating the skin and causing an infection.

Risk Factors    TOP

The following factors increase your chance of developing a pilonidal cyst:

  • Personal or family history of similar problems such as acne, boils, carbuncles, folliculitis, and sebaceous cysts
  • Large amounts of hair in the region
  • Tailbone injury
  • Horseback riding, cycling
  • Prolonged sitting
  • Obesity

Symptoms    TOP

A pilonidal cyst may cause:

  • Painful swelling over your sacrum, which is the area just above your tailbone
  • A foul smell or pus draining from that area

Diagnosis    TOP

Your doctor will ask about your symptoms and medical history. A physical exam will be done. You will be referred to a surgeon for treatment. There are no diagnostic tests required.

Treatment    TOP

Talk with your doctor about the best treatment plan for you. The choice of treatment will depend on the extent of the condition and your general overall health. Treatment options include:

Home Treatment

As with all localized infections under the skin, hot water soaks will draw out the infection. This will not completely cure the condition, but it will help.

Incision and Drainage

The abscess is lanced, the pus drained, and the wound is packed with sterile gauze. This helps it heal from the inside out. But, this usually does not cure the problem because abnormal tissue remains.

Excision    TOP

To completely cure the condition, all affected tissue needs to be removed. This is a more extensive surgical procedure than simple incision and drainage. The surgical wound may be closed with sutures or left open to heal from the inside.

Laser Hair Removal    TOP

There are recent reports that laser hair removal in the area may be an effective treatment for pilonidal cysts.

Prevention    TOP

To help reduce your chance of a pilonidal abscess:

  • Keep the area clean and dry
  • Avoid sitting for a long time on hard surfaces
  • Remove hair from the area

RESOURCES:

American Society of Colon and Rectal Surgeons
http://www.fascrs.org/patients
Family Doctor—American Academy of Family Physicians
http://familydoctor.org

CANADIAN RESOURCES:

The College of Family Physicians of Canada
http://www.cfpc.ca/ForPatients

References:

Pilonidal cyst. American Academy of Family Physicians website. Available at:
...(Click grey area to select URL)
Updated April 2014. Accessed September 4, 2014.
Pilonidal cyst. Swedish Medical Center Seattle website. Available at:
...(Click grey area to select URL)
Accessed September 4, 2014.
Pilonidal disease. EBSCO DynaMed website. Available at:
...(Click grey area to select URL)
Updated February 18, 2014. Accessed September 4, 2014.
Pilonidal sinus and cysts. The Children's Hospital of Philadelphia website. Available at:
...(Click grey area to select URL)
Updated November 2008. Accessed September 4, 2014.
Sadick NS, Yee-Levin J. Laser and light treatments for pilonidal cysts. Cutis. 2006;78:125-128.
Last reviewed August 2014 by Michael Woods, MD
Last Updated: 9/30/2013