A pilonidal sinus (PNS) is a small hole or tunnel in the skin. It may fill with fluid or pus, causing the formation of a cyst or abscess. It occurs in the cleft at the top of the buttocks. A pilonidal cyst usually contains hair, dirt, and debris. It can cause severe pain and can often become infected. If it becomes infected, it may ooze pus and blood and have a foul odor.
The exact cause of this condition isn’t known, but its cause is believed to be a combination of changing hormones (because it occurs after puberty), hair growth, and friction from clothes or from spending a long time sitting. The body considers this hair foreign and launches an immune response against it. This immune response forms the cyst around your hair. Sometimes a person may have multiple sinuses that connect under the skin.
The signs of an infection include:
You may also experience a low-grade fever, but this is much less common.
A pilonidal cyst is a sac filled with hair and skin debris that forms at the bottom of your tailbone. Infected hair follicles usually cause these cysts to develop.
Initial treatments include sitz baths, warm compresses, and antibiotics. However, if the infection is severe enough, you may need surgery.
The two surgical procedures used to treat pilonidal cysts include:
After surgery, your physician might choose to leave the wound open or close it with stitches. The use of stitches may help you heal faster, but there’s a higher chance that your cyst will recur.
The amount of time it takes for you to recover depends on how your surgery was done and if you received stitches. In general, it’ll probably take anywhere from one to three months to completely heal.
Most people can resume their regular activities two to four weeks after surgery.
You may experience some pain or tenderness during the recovery process. This can be managed by:
'Unfortunately, pilonidal cysts do come back after surgery. Studies show recurrence rates are as high as 30 percent.
The cysts may return because the area gets infected again or hair grows near the incision scar.
People who have recurrent pilonidal cysts often develop chronic wounds and draining sinuses.
Here are some ways to prevent a recurrence: