May also be called: Pilonidal Abscess; Pilonidal Sinus; Pilonidal Disease
A pilonidal (pie-luh-NIE-dul) cyst is a pocket (or pit) filled with hair and skin
debris that usually forms in the skin near the end of the tailbone (coccyx) in the
upper part of the cleft between the buttocks.
More to Know
Most doctors believe pilonidal cysts begin to form when a loose hair penetrates
the skin and is
forced deeper into the skin by friction and pressure from long periods of sitting,
tight clothing, bicycling, or other causes. The body's immune
system treats the hair as a foreign substance and forms a cyst around it that
fills with fluid.
Pilonidal cysts may become infected and fill with pus. They can also penetrate
deeper in the tissues and form a channel called a sinus tract. A pilonidal cyst might
have no visible symptoms other than a small dimple in the skin. Cysts that become
infected can be painful, tender, and swollen and may begin to drain fluid or blood.
Keep in Mind
If pilonidal cysts get infected, they can really hurt and should be treated. Treatment
depends on how severe the cyst is, but can involve sitz baths, warm compresses, antibiotics,
and a minor procedure to incise (lance and drain) the infected cyst, or surgery to
clean out the cyst and sinus tract. Surgery is relatively simple, and a person
typically heals completely within a few weeks. However, pilonidal cysts can recur
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