What is the treatment for an abscess?

Management of Abscesses

Incision and drainage (I&D) is the cornerstone of treatment for all abscesses, with antibiotics reserved for specific clinical scenarios. 1

Primary Treatment Approach

• Surgical drainage is the definitive treatment for all abscesses regardless of location or size 2, 1
• For simple, uncomplicated abscesses (induration and erythema limited to the defined area), I&D alone is adequate without antibiotics 2, 1
• No probing for fistulas should be attempted during the procedure to avoid iatrogenic complications 1

Specific Abscess Types and Management

Cutaneous/Skin Abscesses

• Simple superficial abscesses: I&D alone without antibiotics 2, 3
• Complex skin abscesses: I&D plus antibiotics if systemic signs of infection are present, in immunocompromised patients, if source control is incomplete, or with significant cellulitis 2

Perianal and Perirectal Abscesses

• Prompt surgical drainage is essential 2
• Undrained anorectal abscesses can expand into adjacent spaces and progress to systemic infection 2

Intra-abdominal Abscesses

• Small abscesses: Antibiotic therapy alone for 7 days 2
• Large abscesses: Percutaneous drainage combined with antibiotic therapy for 4 days 2
• If percutaneous drainage is not feasible:
  • In non-critically ill, immunocompetent patients: antibiotics alone
  • In critically ill or immunocompromised patients: surgical intervention 2

Lung Abscesses

• Majority (>80%) respond to antibiotics and conservative management 2
• PCD (percutaneous catheter drainage) for cases that persist or worsen despite antibiotics 2
• Surgical resection required in approximately 10% of cases, indicated for prolonged sepsis, hemoptysis, bronchopleural fistula, empyema, lung abscess persisting >6 weeks with antibiotic treatment, or suspected cancer 2

Indications for Antibiotics

Antibiotics should be added to I&D in the following scenarios:

1. Systemic illness signs (fever, tachycardia, tachypnea, leukocytosis)
2. Extensive or rapidly progressing surrounding cellulitis
3. Immunocompromised patients
4. Abscesses in difficult-to-drain locations (face, hand, genitalia)
5. Lack of response to I&D alone
6. Multiple sites of infection 1

Antibiotic Selection

When antibiotics are indicated:

Outpatient Treatment Options

• Clindamycin: 300-450 mg PO TID (covers MRSA, streptococci, anaerobes) 1, 4
• Trimethoprim-sulfamethoxazole: 1-2 DS tablets PO BID (covers MRSA but limited activity against streptococci) 1
• Doxycycline: 100 mg PO BID (covers MRSA but limited activity against streptococci) 1

For Critically Ill or Immunocompromised Patients

• Piperacillin/tazobactam: 4 g/0.5 g q6h or 16 g/2 g by continuous infusion 2
• Eravacycline: 1 mg/kg q12h 2

For Patients with Risk of ESBL-producing Enterobacterales

• Ertapenem: 1 g q24h 2
• Eravacycline: 1 mg/kg q12h 2

Duration of Antibiotic Therapy

• Immunocompetent, non-critically ill patients with adequate source control: 4 days 2
• Immunocompromised or critically ill patients with adequate source control: up to 7 days based on clinical condition and inflammation markers 2, 1
• Patients with ongoing signs of infection beyond 7 days warrant further diagnostic investigation 2

Additional Considerations

• Wound cultures: Consider for complex or recurrent abscesses, especially with risk factors for MRSA 1
• Wound packing: Evidence suggests it may not be beneficial and can cause more pain; may be considered for wounds larger than 5 cm to reduce recurrence 5, 3
• Warm compresses and elevation of the affected area may support treatment 1
• Close follow-up is necessary to evaluate response to treatment 1

Common Pitfalls to Avoid

1. Delaying drainage: Surgical drainage should not be delayed in favor of antibiotics alone (except for specific cases like small intra-abdominal abscesses)
2. Unnecessary antibiotic use: Simple abscesses do not require antibiotics after adequate I&D
3. Inadequate drainage: Ensure complete evacuation of purulent material
4. Missing underlying causes: Investigate for predisposing factors in recurrent abscesses
5. Inappropriate antibiotic selection: Consider local resistance patterns and potential pathogens based on abscess location

Remember that while antibiotics can reach therapeutic concentrations within abscesses 6, their efficacy may be limited by factors such as low pH, protein binding, and bacterial enzyme degradation, making adequate drainage the most critical intervention.