Pilonidal Cysts and Abscesses
Pilonidal cysts occur in the cleft between the buttocks. When infected, it is called an abscess. These cysts may be congenital (present at birth) or may result from hairs penetrating the skin and accumulating beneath the skin. This condition occurs in this area because the cleft between the buttocks allows hair to accumulate. There are usually one or more dimples or small holes overlying the cyst called pilonidal sinuses. Often there are hairs protruding from these small openings. Pilonidal cysts are four times more common in men than women. This condition may be present from birth, but is not usually noticed until adolescence or later. The disease has been referred to as “jeep-driver’s disease”, as it is thought that bumpy driving aggravates previously existing disease.
External appearance ranges from a barely visible dimple at the upper end of the buttock crease to an obvious opening into the cyst. The cyst gradually enlarges and becomes susceptible to infection. When an abscess is present, there is a painful, swollen area with surrounding redness and often pus leaking from the sinuses. A sinus may chronically drain. Infection is more common in the warmer months when the area becomes moister and the bacterial count on the skin increases.
If the cyst develops into an abscess, the best treatment is to make an incision in the skin and drain the pus. Antibiotics are generally not helpful. The procedure can usually be accomplished under local anesthesia in the office. The open wound is packed with gauze, which is then removed in a day or two.
Once the infection is cleared, the entire cyst must be removed to prevent further infection. This is usually scheduled for within a few weeks after the abscess is drained.
Surgery for removal of a pilonidal cyst can be performed using various methods depending on the severity of the pilonidal cyst disease. After completely removing the cyst, the wound can be closed with sutures over a suction drain that removes fluid accumulation. The drain remains in place until the drainage subsides (usually about a week) and is removed at a follow-up visit in the office. The skin sutures are usually removed two weeks after the surgery. Alternatively, the wound, which usually measures about 5-6 inches long by 2-3 inches wide, can be left open and packed with gauze. The gauze is changed every 1-2 days. The wound is allowed to heal in from the sides and bottom, a process that takes several weeks. This may be the operation of choice if infection is encountered during the operation or if the cyst keeps recurring. This surgery is performed under anesthesia as a day-surgery procedure, either at an ambulatory surgery center or hospital.
After surgery, the nurse provides instructions on care of the drain tube. The area around the drain tube and the incision should be kept clean and the drain tube covered with a gauze pad. It is fine to get the area wet in the shower. After showering, the area should be dried carefully and a new dressing placed.
The drainage reservoir should be emptied twice daily and the drainage amount recorded. This record should be taken to the follow up visit with the surgeon.
Students and people who work in an office environment can resume their schedules quickly, even with the drain in place. It is helpful to use a pillow for extra padding when sitting. It is OK to walk, sit, and lay down, but strenuous activity should be avoided.
Pilonidal cysts have a relatively high risk of recurrence – about 20%. Wound infections, wound separation, and wound drainage are also common. These problems can sometimes be treated with dressings, but repeat surgery can be necessary. Other risks include:
- Injury to adjacent tissue
- Complications related to anesthesia