Cellulitis is an acute inflammatory skin infection caused by bacteria like streptococcus. It presents with pain, redness, swelling and warmth in the affected area. Necrotizing soft tissue infection (NSTI), sometimes called "flesh-eating disease", is a rapidly progressive infection of the deep soft tissues that causes tissue death. It is usually caused by streptococcus or staphylococcus and risk factors include immunosuppression. NSTI signs include poorly defined infection margins, edema beyond erythema, and skin gangrene or crepitus. Both require IV antibiotics but NSTI often needs early surgical debridement to remove dead tissue. With treatment, cellulitis has a good prognosis but untreated N

1. Cellulitis vs Necrotizing
Soft Tissue Infection
Afiq Azri bin Zakri
1110252

2. Definition
Cellulitis- Cellulitis is an acute inflammatory condition of the
dermis and subcutaneous tissue.
Necrotising soft tissuse infection- A rapidly progressive infection
of the deep fascia causing necrosis of subcutaneous tissue.
Famously known as flesh eating disease.

3. Etiology
-Most often caused by group A β-hemolytic streptococci
(Streptococcus pyogenes) or Staphylococcus aureus.
-It can also be caused by other bacteria species and fungi and
can be polymicrobial or monomicrobial.

4. Risk Factors
• Cellulitis:
- Immunosuppressed individuals
- A pre-existing skin infection and inflammatory condition of
the skin
• Necrotising soft tissuse infection:
- Immunosuppressed individuals
- Mother in postpartum period, especially if the mother has
diabetes and has undergo caesarean delivery or episiotomy.

5. Pathophysiology
• Infection begins at the site of trauma
-Cut on the skin
-Puncture wound
-Surgical wound
-Insect bites
• Organisms on the skin and its appendages gain entrance to
the dermis and multiply to cause cellulitis.
• Release enzymes and toxins → enable the organisms to
spread through the fascia → occlusion of small
subcutaneous vessels → tissue ischemia and necrosis
(necrotizing soft tissue infection).

6. Signs and Symptoms
Cellulitis
•Pain and tenderness in the affected area
•Redness or inflammation on your skin
•Swollen appearance of the skin
•Warmth in the affected area
•Fever with chills and sweats, tenderness and swollen lymph
nodes.

7. Necrotizing Soft Tissue Infection
• Early signs and symptoms resemble those of cellulitis.
• It can be distinguished by:
- Margins of infection are poorly defined, with tenderness extending
beyond the apparent area of involvement
- Present of oedema, extending beyond the margin of erythema
- Present of bullae and ecchymosis
- Gangrenous skin
- Present of crepitus
- Wooden hard feel subcutaneous tissue
- Severe pain

8. Diagnosis
1. History
• History suggestive to trauma, infection
• Underlying medical illness (eg. DM)
• Treatment (chemotherapy)
2. Physical Examination
• Signs of sepsis (eg. Fever, shock)
• Local signs of NSTI, cellulitis
3. Investigations
• Blood – FBC, CRP
• Tissue C&S
• X-ray

9. Treatment
What to do?
• Manage patient in the ward
• Treatment of shock (if any)
• Start IV broad spectrum antibiotic immediately (eg. IV
penicillin, cephalosporin)
• Refer to the orthopaedic surgeon for surgical
debridement and excision
• Once organism identified, start specific IV antibiotics
• Hyperbaric oxygen (NSTI)
• Skin grafts after the infection goes away to help your
skin heal and look better(NSTI)

10. Prognosis
Cellulitis
- Have good prognosis and can be treatable by antibiotic
treatment to eradicate the infection and avoid complications
and spread of the infection.
Necrotizing soft tissue infection
- Untreated necrotizing fasciitis has a poor prognosis; death
or severe morbidity (for example, limb loss)
- With appropriate treatment, mortality rate can be as high
as 25%
- Morbidity and mortality rates increases with MRSA or other
multidrug resistant organisms

11. Prevention
• Prevention of infection:
- Good hygiene.
- Proper care and inspection of wound and cut especially in
immunosuppressed patient.
- Sterile technique in surgery, episiotomy, caesarean section.
• Seek immediate treatment for any infection.

12. 1. http://journalofethics.ama-assn.org
2. Oxford Handbook of Clinical Medicine, 7th Ed. 2007, Longmore, Wilkinson,
Turmuzei & Chee KC, Oxford University Press.
3. http://www.msdmanuals.com/professional/dermatologic-disorders/bacterial-skin-
infections/cellulitis
4. www.medicinenet.com
5. www.medscape.com
6. http://patient.info/doctor/necrotising-fasciitis-pro
7. Browse Introduction to Investigation and Management of Surgical Disease, 2010,
Norman L., John Black, Kevin G., Steven A., William E. G.,Hodder Arnold Ltd.
Reference