A pilonidal sinus (PNS) is a small cyst or abscess that occurs in the cleft at the top of the buttocks. It can cause severe pain and often becomes infected. If it becomes infected, it may exude pus and blood and emit a foul smell. A pilonidal sinus is a condition that mostly affects men and is common in young adults. A pilonidal sinus (PNS) is a small cyst or abscess that occurs in the cleft at the top of the buttocks. It can cause severe pain and often becomes infected. If it becomes infected, it may exude pus and blood and emit a foul smell. A pilonidal sinus is a condition that mostly affects men and is common in young adults.
Though the exact origin of the disease is not known, its cause is believed to be a combination of:
You may not have any noticeable symptoms at first other than a small, dimple-like depression on the surface of your skin. However, once the depression becomes infected, it will quickly develop into a cyst (closed sac filled with fluid) or an abscess (swollen and inflamed tissue where pus collects).