Cellulitis and necrotising fasciitis


These guidelines have been produced to guide clinical decision making for the medical, nursing and allied health staff of Perth Children’s Hospital. They are not strict protocols, and they do not replace the judgement of a senior clinician. Clinical common-sense should be applied at all times. These clinical guidelines should never be relied on as a substitute for proper assessment with respect to the particular circumstances of each case and the needs of each patient. Clinicians should also consider the local skill level available and their local area policies before following any guideline. 

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To guide staff with the assessment and management of patients presenting to the Emergency Department (ED) with cellulitis or necrotising fasciitis.


Cellulitis is a non-necrotising infection of subcutaneous tissue, usually caused by bacteria. Cellulitis presents as an area of tender, warm skin with overlying oedematous erythema, often associated with regional lymphadenopathy and sometimes systemic signs such as fever or chills.1, 2

Necrotising fasciitis is an aggressive skin/soft tissue infection which causes necrosis of muscle fascia and subcutaneous tissue.5


There is often an obvious injury to the skin (laceration, abrasion) which has served as a point of entry for infection.


  • Most affected children have mild disease and require no investigations.
  • Indicated only if systemic symptoms, suspicion of underlying infection or in immunocompromised patient.
  • Full blood count, C-Reactive protein (CRP) and blood cultures are indicated in the unwell child who appears septic.
  • Refer to Sepsis Recognition and Management – ED Guideline

  • X-ray if cellulitis in close proximity to bone (osteomyelitis, septic arthritis).
  • Swab microculture & sensitivity (MC&S) if discharge is present.
  • Consider Herpes Simplex Virus (HSV) PCR test if suggestive of herpes.
  • Consider biopsy in the immunocompromised patient or if the infection is subacute or chronic.


Cellulitis, erysipelas or soft tissue infection < 4 weeks of age
  • This includes neonates with periumbilical cellulitis (omphalitis) or those with suspected staphylococcal scalded skin syndrome. Refer to Staphylococcal Scalded Skin Syndrome – ED Guideline 
  • All neonates with cellulitis should be admitted for a septic work-up and IV antibiotics
  • Discuss patient with Infectious Diseases or Clinical Microbiology services.
  • Refer to Neonatal Medication Protocols
Mild cellulitis or erysipelas ≥ 4 weeks of age

Moderate cellulitis, erysipelas or soft tissue infection ≥ 4 weeks of age

Severe skin and soft tissue infection (rapidly progressive cellulitis, cellulitis with persisting fever or tachycardia despite 24 hours of oral therapy)
 Periorbital / orbital cellulitis
Suspected or proven necrotising fasciitis 


Consider topical local anaesthetic e.g. lidocaine (lignocaine) with prilocaine (EMLA®) application if patient condition is suggestive of requiring intravenous antibiotics. 


  • Complete and record a full set of observations on the Observation and Response Tool and record additional information on the Clinical Comments chart.
  • Complete and record neurovascular observations (if circumferential or significant swelling).
  • Minimum of hourly observations should be recorded whilst in the ED.


  1. Textbook of Paediatric Emergency Medicine 3rd Edition Cameron P, Browne GJ, Mitra B, et al (2018) Publisher: Elsevier Edition updated 
  2. Nelson Textbook of Pediatrics: 21st Edition Robert M. Kliegman, St Geme JW, Blum MJ et al. 2020 Publisher: Elsevier
  3. Khangura S, Wallace J, Kissoon N, Kodeeswaran T. Management of cellulitis in a pediatric emergency department. Pediatric emergency care. 2007 Nov 1;23(11):805-11.
  4. Schröder, A., Oetzmann von Sochaczewski, C. (2022). Necrotising Fasciitis. In: Belthur, M.V., Ranade, A.S., Herman, M.J., Fernandes, J.A. (eds) Pediatric Musculoskeletal Infections. Springer, Cham. https://doi.org/10.1007/978-3-030-95794-0_36
  5. Wallace HA, Perera TB. Necrotizing Fasciitis. [Updated 2023 Feb 21]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK430756/

Endorsed by:  Co-director, Surgical Services (Nursing)  Date: Oct 2023

 Review date:  Oct 2026

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