II. Epidemiology
- Incidence: 70,000 cases in U.S. per year
- Infection occurs most often in males, age 16 to 30 (uncommon after age 40 years)
III. Risk Factors
IV. Pathophysiology
- Pit forms at skin disruption in gluteal fold (may be injured by embedded loose hairs)
- Pit plugs with hair and keratin
- Pilonidal Cysts form when drainage of pit is blocked, and abscess forms when infected
- Sinus tracts may also develop
V. Symptoms
- Pain in gluteal fold
- No systemic symptoms
VI. Signs
VII. Differential Diagnosis
- Hidradenitis Suppurativa
- Skin Furuncle or Skin Abscess
- Crohn Disease
- Perianal fistula
- Perianal Abscess
- Perirectal Abscess
- Squamous Cell Skin Cancer
VIII. Management: Pilonidal Disease without Abscess
IX. Management: Pilonidal Abscess
-
Incision and Drainage under Local Anesthesia
- Wear Personal Protective Equipment (including mask)
- Prepare the skin in typical fashion (Povidone Iodine or Chlorhexidine and draped)
- Lidocaine with epinephrine Local Anesthetic
- Make small incision lateral to midline (#11 or #15 Blade)
- Do not make incision in midline (risk of non-healing)
- Drain the abscess and break up adhesions with hemostat
- Wound packing is recommended for larger abscesses for the first 48 hours
- Apply a bulky, absorbent dressing
-
Antibiotic Indications
- Surrounding Cellulitis
- Immunocompromised patients
-
Wound care
- Patients should start with sitz baths at 24 hours after Incision and Drainage
- Consider surgical referral for cyst and sinus excision
- Routine surgical Consultation is typically recommended due to the high recurrence rate
- Many surgical approaches exist (e.g. marsupialization, Healing by Secondary Intention, flap closure)
- See recurrence rates below
X. Complications
- Pilonidal Abscess (surrounding Cellulitis may be present)
- Pilonidal Sinus Drainage
- Recurrent infections: 10 to 55%
- Abscess often recurrs in the same location
XI. References
- Marx (2002) Rosen's Emergency Medicine, p. 1952
- Sherman, Bahga and Vietvuong (2022) Crit Dec Emerg Med 36(7): 23-9
- Johnson (2019) Dis Colon Rectum 62(2): 146-57 [PubMed]