L05.9: Pilonidal cyst without abscess

The fatty tissue in the area around your tail bone has become inflamed.

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.

Additional indicator

On medical documents, the ICD code is often appended by letters that indicate the diagnostic certainty or the affected side of the body.

  • G: Confirmed diagnosis
  • V: Tentative diagnosis
  • Z: Condition after
  • A: Excluded diagnosis
  • L: Left
  • R: Right
  • B: Both sides

Further information


This information is not intended for self-diagnosis and does not replace professional medical advice from a doctor. If you find an ICD code on a personal medical document, please also note the additional indicator used for diagnostic confidence.
Your doctor will assist you with any health-related questions and explain the ICD diagnosis code to you in a direct consultation if necessary.


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