What is the recommended management of a cutaneous abscess, including incision and drainage and the indications for antibiotic therapy?

Management of Cutaneous Abscess

Incision and drainage (I&D) is the definitive primary treatment for all cutaneous abscesses, and antibiotics should NOT be routinely prescribed for simple abscesses after adequate drainage. 1, 2

Primary Treatment: Incision and Drainage

• I&D is the cornerstone of treatment and should be performed promptly for all cutaneous abscesses. 1, 2
• After drainage, simply cover the wound with dry sterile gauze—do NOT routinely pack the wound, as packing causes more pain without improving healing outcomes. 1, 2
• Needle aspiration is inadequate and should be avoided, with success rates of only 25% overall and less than 10% for MRSA infections. 1, 2
• Gram stain and culture of pus are recommended for carbuncles and abscesses, though treatment without cultures is reasonable in typical uncomplicated cases. 1, 2

When Antibiotics Are NOT Needed

For simple, uncomplicated abscesses after adequate I&D, antibiotics provide no additional benefit and should not be prescribed. 1, 2, 3

• Simple abscesses are defined by induration and erythema limited to the abscess area, no extension into deeper tissues, and absence of systemic signs. 2
• Multiple studies demonstrate cure rates of 85-90% with I&D alone, regardless of antibiotic use. 1
• A prospective randomized study of 165 patients showed 96% resolution with antibiotics versus 93% without antibiotics after I&D, with no statistical difference (p=0.28). 3

When Antibiotics ARE Indicated

Add antibiotics when systemic inflammatory response syndrome (SIRS) is present or specific high-risk features exist. 1, 2

SIRS Criteria (any of the following):

• Temperature >38°C or <36°C 1, 2
• Tachypnea >24 breaths/minute 1, 2
• Tachycardia >90 beats/minute 1, 2
• White blood cell count >12,000 or <4,000 cells/µL 1, 2

Additional Indications for Antibiotics:

• Severe or extensive disease involving multiple infection sites 1, 2
• Rapid progression with associated cellulitis 1, 2
• Immunocompromised patients or significant comorbidities 1, 2
• Extremes of age 1, 2
• Abscess in difficult-to-drain areas (face, hand, genitalia) 1, 2
• Associated septic phlebitis 1, 2
• Lack of response to I&D alone 1, 2

Antibiotic Selection When Indicated

For outpatient empiric coverage targeting community-acquired MRSA (CA-MRSA), first-line oral options include: 1, 2

• Clindamycin (covers both CA-MRSA and β-hemolytic streptococci) 1, 2
• Trimethoprim-sulfamethoxazole (TMP-SMX) 1, 2
• Doxycycline or minocycline (avoid in children <8 years) 1, 2
• Linezolid 1, 2

Duration: 5-10 days when antibiotics are used. 1, 2

Coverage Considerations:

• If coverage for both β-hemolytic streptococci and CA-MRSA is desired: use clindamycin alone, or combine TMP-SMX or tetracycline with a β-lactam (e.g., amoxicillin), or use linezolid alone. 1
• TMP-SMX, doxycycline, and minocycline have excellent activity against CA-MRSA but uncertain activity against β-hemolytic streptococci. 1

Complex Abscesses

For complex abscesses (perianal/perirectal, IV drug injection sites, or those with significant surrounding cellulitis), perform I&D plus empiric broad-spectrum antibiotics covering Gram-positive, Gram-negative, and anaerobic bacteria. 2

• Perianal/perirectal abscesses require surgical drainage with identification of fistula tracts. 2
• IV drug users require evaluation for endocarditis if systemic signs persist, foreign body removal, and screening for HIV/HCV/HBV. 2

Hospitalized Patients

For hospitalized patients with complicated skin and soft tissue infections, add empirical MRSA coverage pending culture data: 1

• IV vancomycin 1
• Linezolid 600 mg PO/IV twice daily 1
• Daptomycin 4 mg/kg IV once daily 1
• Clindamycin 600 mg IV/PO three times daily (if local resistance <10%) 1

Duration: 7-14 days for complicated infections. 1

Critical Pitfalls to Avoid

• Never use rifampin as single agent or adjunctive therapy for skin abscesses—it leads to rapid resistance development without proven benefit. 1, 2
• Do not routinely prescribe antibiotics for simple abscesses after adequate I&D—this contributes to antimicrobial resistance without improving outcomes. 2, 3
• Do not pack wounds routinely—evidence shows no benefit and increased pain compared to simple dry gauze coverage. 1, 2
• Do not use fluoroquinolones for MRSA coverage—they are inadequate for this indication. 2