Pilonidal disease affects the cleft between the buttocks, usually near the tailbone. Hair and debris can become embedded in small skin pits, producing inflammation, sinus tracts, discharge or an acute abscess. Some people have one painful episode, while others experience repeated swelling or persistent leakage. Treatment depends on whether the disease is acutely infected or chronically recurrent.

Symptoms

An acute pilonidal abscess causes rapid pain, redness and swelling and can make sitting difficult. Pus or blood may drain spontaneously. Chronic disease may cause intermittent discomfort, small openings, staining of clothing or repeated infections. Fever or feeling unwell can occur when infection is more severe.

Why does it develop?

Loose hair can penetrate the skin in a deep or friction-prone cleft and trigger a foreign-body reaction. Sweating, prolonged sitting, coarse hair and previous inflammation may contribute. Pilonidal disease is not simply the result of poor hygiene and can affect people who keep the area clean.

Diagnosis

The characteristic location and skin pits usually make diagnosis straightforward. Examination assesses the number of openings, active infection and previous scars. Imaging is rarely needed but may help if the disease is unusually extensive or close to the anus, where other conditions such as a fistula must be considered.

Treatment options

A painful abscess usually requires incision and drainage. This treats the immediate infection but may not remove the underlying sinus. Recurrent disease can be treated using excision with open healing, off-midline closure, flap procedures or selected minimally invasive methods. Each option has different wound-care, recovery and recurrence considerations.

Aftercare and recurrence

Wound care, keeping the cleft clean and dry, and hair management where advised can support recovery. No procedure guarantees that disease will never recur. Seek urgent care for rapidly worsening pain, spreading redness or fever.

Frequently asked questions

Is a pilonidal sinus a cyst? The term pilonidal cyst is often used, but the condition usually consists of skin pits and sinus tracts.

Can antibiotics cure it? They may treat surrounding infection but do not usually remove an established sinus.

Which operation is best? Choice depends on disease extent, previous treatment, wound priorities and surgeon expertise.