Paeds · infectious-diseases
Cellulitis, abscess and necrotising soft-tissue infection
Also known as Skin and soft-tissue infection · Cellulitis · Cutaneous abscess · Necrotising fasciitis · Necrotising soft-tissue infection · Gas gangrene
Fellowship guide to paediatric cellulitis, cutaneous abscess, and necrotising soft-tissue infection: distinguishing non-purulent from purulent and necrotising disease, age- and MRSA-aware antibiotic selection, incision and drainage as definitive therapy for abscess, and the time-critical recognition and surgical management of necrotising fasciitis including the LRINEC score, empiric broad-spectrum cover, and prognosis.
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Target exams
Red flags
- Pain that is severe and disproportionate to the visible skin changes, suggesting necrotising fasciitis
- Rapidly spreading erythema or induration with systemic toxicity, tachycardia, or shock
- Skin that is numb, tense, or woody, or the presence of haemorrhagic bullae, crepitus, or skin necrosis
- A febrile, toxic-looking child whose skin hurts more than it looks unwell
- Periorbital cellulitis with proptosis, painful eye movement, or reduced vision suggesting orbital extension
- A child with an abscess who is immunocompromised, septic, or failing to improve after incision and drainage
- Sepsis or toxic shock with a soft-tissue focus in any age group
Life stages
Care settings
Clinical exam formats
Board mappings
- Distinguishes cellulitis, abscess, and necrotising soft-tissue infection
- Recognises incision and drainage as definitive therapy for a cutaneous abscess
- Identifies the red flags of necrotising fasciitis and escalates to surgery
- Selects empiric antibiotics by severity, purulence, and local MRSA prevalence
- Applies the LRINEC score as an aid that never excludes necrotising infection
- Coordinates resuscitation, broad-spectrum antibiotics, and urgent surgical debridement
- Management of a child with cellulitis and an abscess
- Recognition and initial management of suspected necrotising fasciitis
- Counselling families about periorbital cellulitis and the risk of orbital extension
- Bedside assessment of a child with a spreading skin infection
- Decision-making around incision and drainage versus antibiotics
- Communication of a necrotising infection diagnosis and the need for surgery
- Level 1: Presents with a skin infection and recognises severity
- Level 2: Investigation and initial management of skin and soft-tissue infection
- Level 3: Management of necrotising infection and toxic shock
- Pathogens and empiric antibiotic regimens for paediatric skin infection
- Clinical and laboratory features of necrotising fasciitis
- Periorbital versus orbital cellulitis and the role of imaging
- History and examination of a child with a skin infection
- Communication of management plan and safety-netting advice
- Structured assessment of a child with suspected necrotising fasciitis
- Empiric antibiotic selection for cellulitis and abscess including MRSA cover
- Indications for incision and drainage and for admission
- Recognition and stabilisation of necrotising soft-tissue infection
- Recognition and resuscitation of the child with severe skin infection
- Appropriate use of antibiotics, drainage, and surgical referral
- Antibiotic stewardship and outpatient safety-netting
- Canadian approach to paediatric skin and soft-tissue infection
- MRSA epidemiology and empiric clindamycin or TMP-SMX selection
- Surgical and intensive care coordination for necrotising infection
Overview & Definition
Skin and soft-tissue infections span a spectrum from mild, self-limiting cellulitis to rapidly fatal necrotising fasciitis, and the clinician's central task is to place each child correctly along that spectrum. The 2014 Infectious Diseases Society of America guidelines frame this as three categories that drive every management decision: non-purulent infection such as cellulitis and erysipelas, purulent infection such as a cutaneous abscess, and necrotising infection that is a surgical emergency. Two organisms, Staphylococcus aureus and Streptococcus pyogenes, cause the great majority of paediatric cases, but their behaviour and the treatment they demand differ sharply across the categories. [1]
Cellulitis is a non-purulent, spreading infection of the dermis and subcutaneous tissue that responds to antibiotics, while a cutaneous abscess is a localised collection of pus within the skin that is cured by incision and drainage and often needs no antibiotic at all. Necrotising soft-tissue infection is fundamentally different: it destroys tissue along fascial planes, thromboses the blood supply to the overlying skin, and cannot be controlled by antibiotics alone because drug cannot reach dead, avascular tissue. The mortality of necrotising infection in children, though lower than in adults, remains substantial, and survival depends on how quickly the surgeon reaches the operating theatre. [2]
The cardinal principle is that the dividing line between a child who needs oral antibiotics and one who needs emergency surgery is a clinical judgement, not a single test. Severe pain out of proportion to the visible skin changes, systemic toxicity, and rapid progression are the features that should trigger escalation long before the laboratory results return. Every clinician assessing a child with a skin infection must actively ask whether this could be necrotising disease, because that question, asked early, is the one that saves limbs and lives. [3]
References12ShowHide
- [1]Stevens DL Practice guidelines for the diagnosis and management of skin and soft tissue infections: 2014 update by the infectious diseases society of America. Clin Infect Dis, 2014.PMID 24947530
- [2]Hua C Necrotising soft-tissue infections. Lancet Infect Dis, 2023.PMID 36252579
- [3]McDermott J Necrotizing Soft Tissue Infections: A Review. JAMA Surg, 2024.PMID 39259555
- [4]Anaya DA Necrotizing soft-tissue infection: diagnosis and management. Clin Infect Dis, 2007.PMID 17278065
- [5]Wong CH The LRINEC (Laboratory Risk Indicator for Necrotizing Fasciitis) score: a tool for distinguishing necrotizing fasciitis from other soft tissue infections. Crit Care Med, 2004.PMID 15241098
- [6]Glennon CM Cellulitis in Pediatric Patients: Recognition and Management in the Era of Evolving Resistance. Am J Clin Dermatol, 2025.PMID 40259138
- [7]Wong SJ Management of pediatric orbital cellulitis: A systematic review. Int J Pediatr Otorhinolaryngol, 2018.PMID 29859573
- [8]Williams KJ Paediatric orbital and periorbital infections. Curr Opin Ophthalmol, 2019.PMID 31261188
- [9]Sanders JE Evidence-based management of skin and soft-tissue infections in pediatric patients in the emergency department. Pediatr Emerg Med Pract, 2015.PMID 25682652
- [10]Vayalumkal JV Children hospitalized with skin and soft tissue infections: a guide to antibacterial selection and treatment. Paediatr Drugs, 2006.PMID 16608371
- [11]Levett D Adjunctive hyperbaric oxygen for necrotizing fasciitis. Cochrane Database Syst Rev, 2015.PMID 25879088
- [12]Yueh CM Etiology, clinical features, management, and outcomes of skin and soft tissue infections in hospitalized children: A 10-year review. J Microbiol Immunol Infect, 2022.PMID 35283045