What is the treatment for a patient with painful perianal abscess or folliculitis, possibly with a history of recurrent abscesses or underlying conditions like diabetes?

Treatment of Painful Perianal/Buttock Abscesses

Incision and drainage is the definitive treatment for painful perianal abscesses and must be performed promptly, with antibiotics reserved only for patients with systemic signs of infection, immunocompromise, diabetes, or significant surrounding cellulitis. 1

Primary Treatment Approach

Surgical Drainage - The Cornerstone

• Incision and drainage is mandatory for all perianal abscesses regardless of size, as this is the only effective treatment 1, 2
• The incision should be placed as close as possible to the anal verge to minimize potential fistula tract length while ensuring complete drainage 1, 2
• Complete and adequate drainage is critical—inadequate drainage leads to recurrence rates as high as 44% 1
• Multiple counter incisions are preferred for large abscesses rather than one long incision, which creates step-off deformity and delays healing 1, 2

Timing of Surgical Intervention

• Emergency drainage (immediate) is required if any of the following are present: 1, 2
  • Sepsis, severe sepsis, or septic shock
  • Immunosuppression or diabetes mellitus
  • Diffuse cellulitis extending beyond the abscess
• Urgent drainage (within 24 hours) for all other cases without the above risk factors 1, 2
• Small, simple perianal abscesses in fit, immunocompetent patients without systemic signs can be managed as outpatients under local anesthesia 1

Antibiotic Therapy - When to Use

Antibiotics Are NOT Routinely Needed

• Do not prescribe antibiotics after adequate surgical drainage in simple cases without systemic involvement 1, 2
• For simple superficial abscesses with induration and erythema limited only to the defined abscess area, incision and drainage alone is sufficient 1

Antibiotics ARE Indicated When:

• Systemic inflammatory response syndrome (SIRS) is present: temperature >38°C or <36°C, tachypnea >24 breaths/min, tachycardia >90 bpm, or WBC >12,000 or <4,000 cells/µL 1
• Markedly impaired host defenses (immunocompromised patients) 1
• Diabetes mellitus 1, 2
• Significant surrounding cellulitis extending beyond abscess borders 1, 2
• Incomplete source control after drainage 1, 2

Antibiotic Selection

• For complex perianal abscesses requiring antibiotics: use empiric broad-spectrum coverage including Gram-positive, Gram-negative, and anaerobic bacteria, as these are frequently polymicrobial 1, 2
• For simple abscesses with SIRS: an antibiotic active against MRSA is recommended 1
• Treatment duration: 5-10 days when antibiotics are indicated 1

Post-Drainage Management

Wound Packing - Controversial and Often Unnecessary

• Packing is not routinely recommended as evidence suggests it is costly, painful, and does not improve healing 1, 2
• The decision to pack should be individualized, but recent evidence favors no packing with simple sterile gauze coverage 1, 3
• If packing is used, it should be changed regularly until cavity heals 1

Follow-Up Considerations

• Routine imaging after drainage is not required 1, 2
• Consider follow-up imaging only for: recurrence, suspected inflammatory bowel disease (IBD), evidence of fistula, or non-healing wounds 1, 2
• Risk factors for recurrence include: inadequate drainage, loculations, horseshoe-type abscess, and delayed time from onset to incision 1, 2

Management of Concomitant Fistulas

If Fistula Is Identified During Drainage

• Perform fistulotomy only for low subcutaneous fistulas not involving sphincter muscle 1, 2
• Place a loose draining seton for any fistula involving sphincter muscle to prevent incontinence 1, 2
• Do not probe to search for fistulas if none is obvious, as this risks iatrogenic complications 1
• Treating obvious fistulas at time of drainage reduces recurrence from 44% to as low as 13% 4

Special Populations and Pitfalls

High-Risk Patients Requiring Aggressive Management

• Diabetic patients are at risk for progression to Fournier's gangrene with gas-forming organisms—maintain high suspicion and low threshold for extensive debridement 5
• Immunocompromised patients (including HIV) may harbor unusual organisms like Actinomyces requiring combined surgical and prolonged antibiotic therapy 6
• These patients require emergency drainage regardless of abscess size 1, 2

Recurrent Abscesses

• Search for local causes: pilonidal cyst, hidradenitis suppurativa, foreign material, or underlying Crohn's disease 1
• Culture recurrent abscesses early and treat with 5-10 days of pathogen-directed antibiotics 1
• Consider decolonization for recurrent S. aureus: intranasal mupirocin twice daily for 5 days, daily chlorhexidine washes, and decontamination of personal items 1

Common Pitfalls to Avoid

• Never delay drainage for imaging in clinically obvious cases—diagnosis is clinical 2
• Never use needle aspiration as primary treatment—recurrence rates are 41% vs. 15% with proper incision and drainage 1
• Do not prescribe antibiotics reflexively—they are unnecessary after adequate drainage in most cases 1, 2
• Avoid inadequate drainage—this is the primary cause of the high 44% recurrence rate 1