A cyst is a lump that develops within a tissue but whose presence is abnormal and detached from the tissue in question. A pilonidal cyst is a small mass under the skin and localized mainly in the crease of the buttocks, along the tailbone. This may also be called a pilonidal sinus. It most often affects young adults, and more frequently men. It essentially contains hair and skin, and tends to be infectious and recurrent. This is a totally benign cyst, but during its inflammatory stage it can trigger severe pain. It can also sometimes become a fistula, i.e. dig into the body and leak its infected content there within.
A cyst can easily be overlooked when it appears without accompanying symptoms.
Some signs are nevertheless revealing:
- appearance of a palpable mass in the cleft;
- more or less severe pain, depending on the intensity of inflammation;
- inflammatory response in case of infection: redness, warmth, pus, leading also to other complications such as an abscess or a fistula.
The diagnosis is clinical. It is made by a physician after examining the area (palpation of the cyst). Signs of inflammation (specified above) are also observed. In case of infection, a biopsy can be taken to determine the causative organism.
Treatment is primarily surgical. Removal of pilonidal cyst is performed in the operating room under general anesthesia. In the case of an abscess secondary to infection, the surgeon will drain the latter to remove pus. Antibiotics will be administered in parallel.