Pilonidal Sinus, Cyst & Abscess: Symptoms, Causes and Modern Treatment Options

A Complete Patient Guide to Pilonidal Disease, Abscess Drainage, Surgery & Laser Treatment in Agra

By Dr. Karan R. Rawat
MBBS, MS, FIAGES, FMAS, DMAS, FICRS, FALS, FISCP, FAIAS, MCLS, FCLS
Gastrointestinal, Colorectal, Proctology, Laser, Laparoscopic & General Surgeon, Agra

Medically reviewed: September 2026

Do you have a painful lump, recurrent swelling, pus discharge, bleeding or a small hole near the tailbone between the buttocks?

You may be suffering from pilonidal disease.

Patients commonly use three different terms:

  • Pilonidal cyst

  • Pilonidal sinus

  • Pilonidal abscess

Although related, they do not always represent exactly the same stage of disease.

A small pit may remain silent for months or years. Another patient may develop recurrent discharge through a sinus opening. Sometimes the area suddenly becomes extremely painful, swollen and filled with pus—forming a pilonidal abscess.

Understanding which stage you have is important because the treatment is different.

What Is Pilonidal Disease?

Pilonidal disease usually occurs in the natal cleft—the groove between the buttocks close to the tailbone.

Loose hairs can penetrate or become embedded in the skin, triggering inflammation and formation of pits, cavities and sinus tracts beneath the skin. Pilonidal disease is particularly common in young adults and is more frequent in men. Prolonged sitting and increased body hair can contribute to its development.

The condition may present as:

Pilonidal pit

A tiny opening in the midline.

Pilonidal cyst

A cavity or pocket beneath the skin, often containing hair and debris.

Pilonidal sinus

A chronic tunnel connecting the diseased cavity beneath the skin to one or more openings on the surface.

Pilonidal abscess

An acutely infected cavity containing pus, producing significant pain and swelling.

These can be viewed as different manifestations of the same underlying condition: pilonidal disease. The 2024 European Society of Coloproctology guideline uses pilonidal disease as an umbrella term encompassing pilonidal sinus disease and pilonidal cysts occurring within the natal cleft.

Pilonidal Cyst vs Pilonidal Sinus vs Pilonidal Abscess

Patients often become confused because these terms are used interchangeably.

Pilonidal Cyst

A pilonidal cyst refers to a cavity beneath the skin near the tailbone that may contain:

  • Hair

  • Keratin

  • Skin debris

  • Inflammatory tissue

It may initially produce no symptoms.

If it becomes inflamed or infected, it can become painful and progress to an abscess.

Pilonidal Sinus

A pilonidal sinus is a small tunnel or tract underneath the skin.

You may notice:

  • One or more tiny holes in the buttock cleft

  • Intermittent pus discharge

  • Blood-stained discharge

  • Bad smell

  • Recurrent pain

  • Recurrent swelling

A chronic pilonidal sinus can repeatedly become infected and settle again.

Pilonidal Abscess

A pilonidal abscess occurs when the cavity becomes acutely infected and fills with pus.

Typical symptoms include:

Severe pain

Rapidly increasing swelling

Redness

Tenderness

Pus formation

Difficulty sitting

Fever in some patients

Symptoms can develop over just a few days. An acutely painful, swollen pilonidal abscess usually requires drainage rather than relying on medicines alone.

Why Does Pilonidal Sinus Develop?

The modern understanding is that most pilonidal disease is acquired rather than something a person is simply born with.

Loose hairs can collect within the deep cleft between the buttocks.

With:

  • Friction

  • Pressure

  • Movement

  • Sweating

  • Prolonged sitting

hair can penetrate the skin.

The body identifies the embedded hair as a foreign material and produces inflammation around it. Over time, pits, cavities and sinus tracts may develop.

Who Is More Likely to Develop Pilonidal Disease?

Risk factors can include:

  • Young adulthood

  • Male sex

  • Thick or coarse body hair

  • Deep natal cleft

  • Prolonged sitting

  • Sedentary lifestyle

  • Obesity

  • Excessive sweating

  • Local friction

  • Recurrent trauma to the area

People whose work involves sitting for prolonged periods—such as office workers or drivers—may be more susceptible.

But it is important to remember:

Pilonidal disease is not simply caused by poor hygiene.

Even people with good personal hygiene can develop it.

What Are the Symptoms of Pilonidal Sinus?

A patient may initially notice only:

A small hole above the anus near the tailbone.

Other symptoms can include:

  • Recurrent swelling

  • Pain while sitting

  • Pus discharge

  • Blood-stained discharge

  • Wetness of underwear

  • Foul smell

  • Recurrent boils in the same area

  • Multiple openings

  • Hardness beneath the skin

A chronic sinus may continue discharging for weeks, months or even years.

The discharge may temporarily stop, causing the patient to assume the disease has disappeared.

However, the underlying tract may still remain.

Symptoms of a Pilonidal Abscess

An abscess generally presents much more dramatically.

You may suddenly develop:

  • Severe pain near the tailbone

  • A tender lump

  • Redness

  • Increasing swelling

  • Warm skin

  • Difficulty sitting

  • Difficulty sleeping on your back

  • Pus discharge if the abscess bursts

  • Fever or feeling unwell in some cases

An infected pilonidal cyst can become extremely painful.

Do not repeatedly squeeze or puncture the swelling yourself.

A painful abscess needs proper surgical assessment.

Is Pilonidal Sinus the Same as Anal Fistula?

No.

This distinction is extremely important.

A pilonidal sinus usually originates in the skin of the buttock cleft near the tailbone.

An anal fistula usually develops as an abnormal tract related to infection around the anal canal.

The two conditions require different assessment and treatment.

Pilonidal disease can occasionally extend lower than usual, which may create diagnostic confusion. The ASCRS-derived guidance recommends examination to exclude conditions such as anal fistula, hidradenitis and Crohn-related disease when appropriate.

If the opening is very close to the anus, proper specialist assessment becomes particularly important.

How Is Pilonidal Sinus Diagnosed?

In most patients, diagnosis is primarily clinical.

The surgeon examines the natal cleft looking for:

  • Midline pits

  • Secondary openings

  • Hair embedded within pits

  • Pus

  • Chronic discharge

  • Induration

  • Acute abscess

  • Previous surgical scars

  • Recurrent disease

Most straightforward cases do not require extensive investigations.

The 2024 European Society of Coloproctology guideline states that evaluation is largely based on clinical assessment, with additional investigation when another condition such as an anal fistula is suspected.

Does Every Pilonidal Sinus Need Surgery?

No.

An asymptomatic pilonidal pit or disease without inflammation does not automatically require preventive surgery.

The 2024 European guidelines specifically state that prophylactic intervention is not recommended for asymptomatic pilonidal disease.

Treatment becomes more relevant when there is:

  • Pain

  • Recurrent swelling

  • Discharge

  • Bleeding

  • Repeated infection

  • Abscess formation

  • Multiple sinus openings

  • Chronic non-healing disease

What Is the Treatment for a Pilonidal Abscess?

This deserves special emphasis.

An abscess contains pus.

Giving only tablets may reduce surrounding infection or inflammation in selected circumstances, but antibiotics cannot reliably empty a significant collection of pus.

For an acute pilonidal abscess, treatment generally involves:

Incision and Drainage

A small opening is created to allow:

pus + infected material + pressure

to escape.

Both current European guidance and ASCRS-derived recommendations identify drainage as the main treatment for an acute pilonidal abscess.

The relief after adequate drainage can be dramatic because the pressure inside the abscess is released.

Are Antibiotics Enough for a Pilonidal Abscess?

Usually not if a true pus-filled abscess is present.

Antibiotics may be appropriate when there is:

  • Significant surrounding cellulitis

  • Fever or systemic infection

  • Other clinical indications

  • Increased infection risk

But antibiotics alone do not remove the underlying pus collection or chronic sinus tract.

The 2024 European guideline specifically notes that antibiotics may be considered during infection but should not be regarded as curative treatment for symptomatic pilonidal disease.

If My Abscess Is Drained, Is My Pilonidal Disease Permanently Cured?

Not necessarily.

Drainage treats the acute emergency—the abscess.

But the pits, hair, debris or sinus tract responsible for the disease may remain.

Consequently, some patients subsequently develop:

  • Another abscess

  • Chronic discharge

  • Recurrent swelling

  • Persistent pilonidal sinus

Older ASCRS guideline data cited in American Family Physician reported that a substantial proportion of patients