• MRSA is the most common cause of purulent skin and soft-tissue infections.[1][2][3]

Clinical Features

  • Tender nodular region with surrounding induration
  • Fluctuance
  • Surrounding erythema

Differential Diagnosis

  • Cyst
  • Vascular malformation

Skin and Soft Tissue Infection



Fluctulance on exam
Abscess on ultrasound
  • Clinical exam: fluctulance +/- erythema
  • Soft tissue ultrasound can differentiate between abscess and cellulitis
    • Assess for fluid collection and swirl within the collection


  • Incision and drainage
  • Packing
    • Abscess >5 cm in diameter
    • Pilonidal abscess
    • Abscess in an immunocompromised or diabetic patient
  • Alternative to packing is loop drainage technique with vessel ties[4] or cut the proximal cuff of the sterile gloves[5]
    • Failure rate of 4.1% for loop vessel technique vs 9.8% for conventional packing. [6]
    • Other advantage is don’t have to keep coming back to the ER for painful repacking.
    • Home Care (copied from Pediatric EM Morsels)[7]
      • Keep area clean.
      • Can cover with gauze to absorb the residual drainage.
      • Can shower and/or bathe.
    • The loop drain can be removed when (copied from Pediatric EM Morsels)[8]
      • Drainage has stopped.
      • Cellulitis has improved.
      • Usually is within 7-10 days.
  • Antibiotics
    • Although withholding antibiotics is part of Choosing wisely ACEP, new evidence suggest antibiotic NNT of 14 to prevent 1 treatment failure[9]
    • TMP/SMX DS BID x 5 days (all abscesses)[10]
    • Consider more aggressive antibiotic treatment if concomitant cellulitis



  • Reserved for significantly ill patients or those requiring surgical intervention


  • Appropriate for majority of patients
    • Follow up in 2 days for wound check

See Also

External Links


  1. Maligner D et al. The prevalence of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) in skin abscesses presenting to the pediatric emergency department. N C Med J. 2008 Sep-Oct;69(5):351-4.
  2. Pickett A et al. Changing incidence of methicillin-resistant staphylococcus aureus skin abscesses in a pediatric emergency department. Pediatr Emerg Care. 2009 Dec;25(12):831-4.
  3. Bradley W. Frazee et al. High Prevalence of Methicillin-Resistant Staphylococcus aureus in Emergency Department Skin and Soft Tissue Infections http://dx.doi.org/10.1016/j.annemergmed.2004.10.011
  4. Incision and Loop Drainage of Abscess BY SEAN M. FOX Pediatric EM Morsels
  5. Sterile Glove Used As a Drain for a Skin Abscess? SinaiEM
  6. Am J Emerg Med, 2018. Comparison of the loop technique with incision and drainage for soft tissue abscesses: A systematic review and meta-analysis.
  7. Incision and Loop Drainage of Abscess BY SEAN M. FOX Pediatric EM Morsels
  8. Incision and Loop Drainage of Abscess BY SEAN M. FOX Pediatric EM Morsels
  9. Talan DA, et al. Trimethoprim–Sulfamethoxazole versus placebo for uncomplicated skin abscess. NEJM. 2016; 374(9):823-832.
  10. EBQ:TMP-SMX vs Placebo for Uncomplicated Skin Abscess