Pilonidal Cyst: Symptoms, Types, Causes and Treatment

Pilonidal cysts are a common yet often misunderstood condition that primarily affects young adults. These cysts can cause significant discomfort and lead to troubling complications if not properly managed. Understanding the key symptoms, various types, underlying causes, and available treatments is crucial for both patients and healthcare providers. In this comprehensive overview, we draw on the latest research to clarify what you need to know about pilonidal cysts.

Symptoms of Pilonidal Cyst

Pilonidal cysts can be subtle in their early stages but often become dramatically uncomfortable when symptoms escalate. Recognizing the signs early can lead to prompt treatment and reduce the risk of complications.

Main Symptom	Description	Frequency/Notes	Source(s)
Pain	Localized, often severe	Especially when inflamed	1, 4, 7
Swelling	Noticeable lump (mass) in affected area	May be fluctuant or firm	4, 7
Redness	Surrounding skin appears erythematous	Indicates inflammation	4, 7
Discharge	Pus or blood may drain from sinus	Common in chronic or abscess	4, 7
Abscess	Sudden, painful swelling	Acute presentation	4, 7
Fistula	Sinus tract to skin surface	Seen in chronic cases	4, 7
Asymptomatic	Pits without pain or discharge	May not require treatment	4

Table 1: Key Symptoms of Pilonidal Cyst

Understanding Pilonidal Cyst Symptoms

Pilonidal cysts typically manifest in the sacrococcygeal region, near the tailbone at the top of the buttocks. The earliest sign may be a small pit or dimple in the skin, which is often asymptomatic. However, when inflammation or infection develops, symptoms can rapidly intensify.

Pain and Swelling

• Pain is the most prominent symptom, especially when the cyst becomes infected or forms an abscess. The pain is usually localized and can be severe, making sitting or moving uncomfortable. Swelling or a palpable mass is often present and may feel fluctuant (fluid-filled) if an abscess has formed 1, 4, 7.

Redness and Discharge

• Redness of the overlying skin is a common indicator of local inflammation.
• Discharge of pus or blood may occur from a sinus opening, particularly in chronic or abscessed cases. This drainage can be foul-smelling and is a sign of secondary bacterial infection 4, 7.

Acute vs. Chronic Presentations

• Acute pilonidal abscess: Presents suddenly, with rapid-onset swelling, pain, and sometimes fever. The area may be warm and tender 4.
• Chronic fistulizing form: Characterized by persistent drainage and the presence of one or more sinus tracts. Chronic cases may not be as painful but tend to linger and can flare up repeatedly 4, 7.

Asymptomatic Cases

• Some individuals have small pits or tracts without symptoms. These are considered asymptomatic and typically do not require intervention unless they become problematic 4.

Types of Pilonidal Cyst

Pilonidal disease can present in several distinct forms, each with its own clinical implications. Understanding these types helps guide effective management.

Type	Description	Typical Features	Source(s)
Acute Abscess	Sudden infection, pus accumulation	Painful, swollen, may require drainage	4, 7
Chronic Sinus	Persistent tract, intermittent drainage	Less pain, sinus opening(s)	4, 7
Complex Disease	Multiple tracts, recurrent abscess/fistulae	Difficult to treat, higher recurrence	4, 7
Asymptomatic	Pits without current symptoms	No active infection or pain	4
Rare Locations	Cysts in atypical areas (e.g., genitalia, scalp, interdigital)	Unusual presentation	3, 7
Malignant Change	Squamous cell carcinoma arising in cyst	Extremely rare, locally aggressive	1, 2

Table 2: Types of Pilonidal Cyst

Exploring Pilonidal Cyst Types

Acute Pilonidal Abscess

• Occurs when a cyst becomes infected, leading to a rapid build-up of pus.
• Symptoms are intense and may require urgent drainage 4, 7.

Chronic Fistulizing Form

• The most common presentation, featuring a persistent sinus tract from which fluid may intermittently drain.
• Usually less painful but can become problematic due to recurring infection or persistent drainage 4, 7.

Complex Pilonidal Sinus Disease

• Involves multiple sinus tracts or repeated abscess formation.
• These cases are more difficult to manage and have a higher risk of recurrence 4, 7.

Asymptomatic Pilonidal Pits

• Some individuals have skin pits in the natal cleft without any symptoms.
• These do not require treatment unless they become symptomatic 4.

Rare and Unusual Presentations

• While most pilonidal cysts are found near the tailbone, rare cases have been reported on the scalp, genitals (e.g., clitoris, penis), and even between the fingers (barber’s disease) 3, 7.

Malignant Degeneration

• Extremely rare, chronic pilonidal cysts can undergo malignant transformation, usually into squamous cell carcinoma.
• These cases are locally aggressive and require extensive surgical resection 1, 2.

Causes of Pilonidal Cyst

The debate over the origin of pilonidal cysts has largely shifted from congenital to acquired theories. Multiple risk factors contribute to their development.

Cause/Risk Factor	Mechanism or Contribution	Typical Patient	Source(s)
Hair Penetration	Loose hair shafts penetrate skin	Hirsute (hairy) individuals	5, 8, 9
Local Trauma	Friction or pressure damages skin	Sedentary workers, drivers	7, 9
Poor Hygiene	Encourages infection and hair accumulation	All ages, especially young adults	7, 9
Deep Natal Cleft	Skin folds trap hair, promote penetration	Obese or anatomically predisposed	9
Obesity	Increases depth of natal cleft, sweating	Overweight individuals	9
Family History	Possible hereditary predisposition	Some familial clustering observed	9
Congenital Theory	Embryonic remnants (now less accepted)	Historical perspective	7, 8, 9

Table 3: Causes and Risk Factors

Unpacking the Causes

Acquired Nature

• Hair penetration: The consensus is that pilonidal cysts are acquired, resulting from loose hair shafts being driven into the skin of the natal cleft. The hair acts as a foreign body, triggering a chronic inflammatory response 5, 8, 9.
• Friction and trauma: Activities that cause repeated friction or pressure (prolonged sitting, cycling, driving) increase the risk of hair penetration and cyst formation 7, 9.

Additional Risk Factors

• Obesity and anatomy: A deep natal cleft and obesity both facilitate the trapping of hair and debris, raising the risk of cyst development 9.
• Poor hygiene: Inadequate cleansing can allow hair and bacteria to accumulate, further increasing the risk 7, 9.
• Family history: Some studies suggest a possible hereditary factor, though this is less well-defined 9.

The Congenital Debate

• Early theories proposed a congenital origin—embryonic cell rests or developmental anomalies—but histological studies and clinical evidence now overwhelmingly support the acquired theory 7, 8, 9.

Pathogenesis

• Once hair penetrates the skin, the body mounts a foreign-body immune response, leading to chronic inflammation, cyst, and sinus tract formation 8.
• Secondary infection is common, leading to abscess or continuous drainage from sinus tracts 4, 8.

Treatment of Pilonidal Cyst

Management of pilonidal cysts has evolved significantly, with a wide range of surgical and non-surgical options now available. The goal is to relieve symptoms, prevent recurrence, and minimize morbidity.

Treatment	Approach/Technique	Key Advantages/Notes	Source(s)
Incision & Drainage	Acute abscess management	Quick relief, not definitive	4, 5, 7
Excision	Surgical removal of cyst/sinus	May be open or closed healing	5, 7, 9
Curettage	Scraping out cyst contents	May be combined with excision	5, 7
Minimally Invasive	Laser, endoscopic, flap procedures	Less pain, faster recovery	10, 11, 12, 9
Laser Therapy	Cyst destruction, hair removal	Minimally invasive, low recurrence	10, 11
Flap Surgery	Limberg, Karydakis flaps	For complex/recurrent disease	9
Antibiotics	Adjunct for infection	Not curative alone	4
Conservative	Hygiene, hair removal	For asymptomatic or early cases	4, 7

Table 4: Treatment Options for Pilonidal Cyst

Treatment Strategies

Acute Abscess Management

• Incision and Drainage: The first step for an acute abscess is to drain the pus, which rapidly relieves pain and swelling. This is usually performed under local anesthesia. Sometimes curettage (scraping out debris) is also done 4, 5, 7.

Definitive Surgical Options

• Excision: Surgical removal of the entire cyst and sinus tract. The wound may be left open to heal by secondary intention or closed with sutures. Open healing lowers recurrence but prolongs recovery. Closed wounds allow faster healing but may have higher recurrence 5, 7, 9.
• Flap Procedures: For complex or recurrent disease, tissue flaps (e.g., Limberg or Karydakis) may be used to flatten the natal cleft and reduce recurrence 9.

Minimally Invasive and Newer Techniques

• Laser Therapy: Innovative techniques use a radial laser probe to destroy the cyst and sinus tract. Laser hair removal (e.g., Nd-YAG) is also effective for some patients, reducing recurrence and postoperative pain 10, 11.
• Endoscopic Pilonidal Sinus Treatment (E.P.Si.T.): Uses a small scope to remove debris and cauterize the tract, offering less postoperative discomfort and faster return to normal activities 12.

Adjunctive and Conservative Measures

• Antibiotics: Used for acute infection but not as standalone treatment 4.
• Hygiene and Hair Removal: Regular cleaning and removal of hair in the area can prevent recurrence, especially after surgical treatment 4, 7.

Special Considerations

• Histological Examination: All excised tissue should be examined microscopically to rule out rare malignant transformation 1.
• Recurrence: Rates vary widely depending on the technique used, with minimally invasive and flap methods showing promise in reducing recurrence 9, 10, 11, 12.

Conclusion

Pilonidal cysts are a prevalent and challenging condition, but with the right knowledge, they can be managed effectively. Here’s a recap of the essential points:

• Symptoms: Range from pain, swelling, redness, and discharge to asymptomatic skin pits.
• Types: Include acute abscess, chronic sinus, complex disease, rare locations, and very rarely, malignant transformation.
• Causes: Most cases are acquired, with hair penetration, local trauma, deep natal cleft, and poor hygiene as major factors.
• Treatment: Encompasses incision and drainage, surgical excision, minimally invasive techniques, and preventive hygiene. Newer modalities like laser and endoscopic treatments show excellent results.

Remember: Early recognition and appropriate management are crucial to prevent complications and recurrence. If you suspect a pilonidal cyst, consult a healthcare provider for tailored advice and treatment.