L05: Pilonidal cyst

L05.0: Pilonidal cyst with abscess

The cleft between the buttons is often affected. If hair on a person’s back or bottom rubs together for a long time, it can become ingrown and cause inflammation. Less often, bruises or congenital malformation of the buttocks may also cause this inflammation. Heavy sweating, obesity, sitting down for long periods, or poor body hygiene can prolong the inflammation so that it persists for a long time. Most of the red, swollen sites are very sensitive to pressure. Small openings in the skin leaking pus are sometimes visible.

In your case, so much pus has collected that a pus-filled cyst has formed on your buttocks. To prevent the inflammation from spreading, the body has formed a firm covering around this changed tissue. If the drainage path for the pus gets blocked, this is often very painful.