What is the guideline for managing perianal abscesses?

Management of Perianal Abscesses: Current Guidelines

The primary treatment for perianal abscesses is surgical incision and drainage, with timing based on the presence and severity of sepsis. 1

Diagnosis and Assessment

• Clinical diagnosis is usually sufficient for typical perianal abscesses 1
• Imaging may be considered in cases with:
  • Atypical presentation (lower back pain, severe anal pain without fissure, urinary retention) 1
  • Suspected supralevator or intersphincteric abscess 1
  • Suspicion of Crohn's disease 1
• When imaging is needed, CT scan offers advantages of short acquisition time and widespread availability, though with limitations in spatial resolution 1

Surgical Management

• Incision and drainage is the cornerstone of treatment for all perianal abscesses 1
• The incision should be kept as close as possible to the anal verge to minimize potential fistula length while ensuring adequate drainage 1
• Complete drainage is essential, as inadequate drainage is associated with high recurrence rates (up to 44%) 1
• Specific management based on abscess location:
  • Perianal and ischioanal abscesses: Incision and drainage via overlying skin 1
  • Intersphincteric abscesses: Drainage into rectal lumen, possibly with limited internal sphincterotomy 1
  • Supralevator abscesses: Drainage via rectal lumen (if extension of intersphincteric abscess) or externally via skin (if extension of ischioanal abscess) 1

Timing of Surgery

• Emergency drainage is indicated for patients with:
  • Sepsis, severe sepsis, or septic shock 1
  • Immunosuppression 1
  • Diabetes mellitus 1
  • Diffuse cellulitis 1
• In the absence of these factors, surgical drainage should ideally be performed within 24 hours 1
• Outpatient management can be considered for fit, immunocompetent patients with small perianal abscesses without systemic signs of sepsis 1

Management of Concomitant Fistulas

• If an obvious fistula is found during abscess drainage:
  • Perform fistulotomy only for low fistulas not involving sphincter muscle (subcutaneous fistula) 1
  • Place a loose draining seton for fistulas involving any sphincter muscle 1
  • Avoid probing to search for possible fistulas when not obvious, to prevent iatrogenic complications 1
• Evidence shows that fistula treatment at the time of abscess drainage significantly reduces recurrence rates but may increase risk of continence disturbances 1, 2

Post-Operative Care

• The role of wound packing after abscess drainage remains controversial 1
• A Cochrane review found insufficient evidence to determine whether packing influences healing time, wound pain, development of fistulae, or abscess recurrence 3
• Some evidence suggests packing may be costly and painful without adding benefit to the healing process 1

Antibiotic Therapy

• Antibiotics are not routinely indicated after adequate surgical drainage 1
• Consider antibiotics only in cases of:
  • Sepsis and/or surrounding soft tissue infection 1
  • Disturbances of immune response 1
  • High-risk patients or those with risk factors for multidrug-resistant organism infection 1

Follow-Up and Recurrence Prevention

• Routine imaging after incision and drainage is not required 1
• Consider follow-up imaging in cases of:
  • Recurrence 1
  • Suspected inflammatory bowel disease 1
  • Evidence of fistula or non-healing wound 1
• Risk factors for recurrence include:
  • Inadequate drainage 1
  • Loculations 1
  • Horseshoe-type abscess 1
  • Delayed time from disease onset to incision 1

Special Considerations

• Incision and seton drainage may be superior to incision and drainage alone for high perianal abscesses, with higher cure rates, shorter wound healing time, and lower recurrence rates 4
• In infants, non-operative management without general anesthesia may be considered, with studies showing over 75% healing without further intervention 5