A pilonidal (pi-lo-ni-dal) cyst is a collection of hair, skin debris, and other tissue. It is almost always located near the tailbone (bottom of spine) in the buttock crease.
Pilonidal cysts usually occur when hair cuts the skin and then becomes trapped. The cyst can sometimes drain blood or fluid. If it becomes infected it can be extremely painful.
A pilonidal cyst can be diagnosed during an exam. If your child has a pilonidal cyst, the provider will see a dimple, or an opening in the skin near the tailbone. The cyst will not hurt your child unless it becomes infected. Signs of an infected cyst are:
If the cyst is not infected, it may be treated with hair removal and good hygiene. This may help it go away or prevent it from getting infected.
If the cyst becomes infected it may be treated with antibiotics. Sometimes antibiotics are not enough to treat the infection. In some cases, the infection turns into an abscess. An abscess is a painful collection of pus and other infected material underneath the skin. If the pus and infected material can’t drain out the area will get more swollen and painful. An abscess may need to be drained in order to heal. To do this, a provider will numb the area first. A cut (incision) will be made to drain the pus and infected material.
When is surgery needed?
There are many treatments available for pilonidal cysts. Your child may need surgery if they have an infected cyst or it keeps coming back.
There are several types of surgeries. Your surgeon will discuss which they feel is best for your child. Your child will be given general anesthesia for any of these surgeries. This means they will be given medicine to make them sleep without pain during the surgery. They might need to stay overnight in the hospital after surgery.
Closed wound surgery
For some operations the wound is closed after the cyst is removed. There may be a quicker recovery from this surgery but there is a chance of getting a wound infection because bacteria (germs) are more likely to grow in the area. Also, a closed wound could re-open after the operation.
Open wound surgery
During an open wound surgery, the cyst is removed. Then the wound is left open so it can heal from the inside out. Since bacteria need a closed space to grow it is important to keep it open so it can heal. This type of wound will take several weeks to close.
An infected cyst can be very painful until it is drained. Because the cyst is located near the tailbone, sitting for long periods of time can cause pain. After the infection is drained, your provider may give your child a prescription for pain medicine.
This information is not specific to your child but provides general information. If you have any questions, please call your clinic.
Updated 10/2019
This page is not specific to your child, but provides general information on the topic above. If you have any questions, please call your clinic. For more reading material about this and other health topics, please call or visit Children's Minnesota Family Resource Center library, or visit www.childrensmn.org/educationmaterials.
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