Infections of Skin & Soft Tissue Flashcards
What is cellulitis?
Acute bacterial infection of the dermis and hypodermis
*NOTE: hypodermis also referred to as subcutaneous tissue, subcutis etc..
State some risk factors for developing cellulitis
- Trauma
- Insect bites
- Ulcers
- Tinea pedis (athlete’s foot)
- Venous insufficiency
- Lymphoedema
- Diabetes
- Obestiy
State the 2 most common causative organisms of cellulitis
- Streptococcus pyogenes (group A Streptococcus)
- Staphylococcus aureus
State signs & symptoms of cellulitis
Symptoms commonly found unilaterally on extremities or on face:
- Spreading erythema (with poorly defined margin)
- Pain
- Oedema/swelling
- Warm to touch
- Golden yellow crust may be present (indicated Staphylococcus aureus infection)
- Fever
- Malaise
May also see evidence of of blisters, ulcers, lymphangitis, lymphadenopathy
Discuss what investigations you would do if you supect a pt has cellulitis, include:
- Bedside
- Bloods
- Imaging
Bedside
- ?skin swab or aspirate
Bloods
- FBC: leucocytosis
- CRP: raised in inflammation/infection
- ESR: raised in inflammation/infection
- U&Es: baseline renal function to allow sensible antibiotic choice
- Blood culture & sensitivities: find causative organism
Imaging
- ?Ultrasound, x-ray or MRI: only if uncertain about diagnosis/suspect underlying abscess or necrotising fasciitis
What classification is used to guide the management of cellulitis; describe this classification
Eron Classification
- Class 1 – no systemic toxicity or comorbidity
- Class 2 – systemic toxicity or comorbidity
- Class 3 – significant systemic toxicity or significant comorbidity
- Class 4 – sepsis or life threatening
Discuss the management of cellulitis
-
Antibiotics (choice depends on Eron classification):
- Class I: oral flucloxacillin- manage as outpatient
- Class II: IV flucloxacillin- may be suitable for 48hr hosp admission
- Class III: IV flucloxacillin- hosp admision
- Class IV: IV flucloxacillin- hosp admission.
- Surgery may be required for pts with class IV cellulitis
- Identify and manage and underlying risk factors
- Prophylaxis is cellulitis is recurrent (2 or more episodes at same site)
Flucloxacillin is usually first line antibiotic for cellulitis; state some other antibiotics which may be used
- Co-amoxiclav (if infection around nose or eyes “danger triangle”)
- Clindamycin
- Clarithromycin (if penicillin allergic)
- Vancomyin (if MRSA may be causative organism)
Prophylaxis is given for pts with recurrent cellulitis (two or more episodes at same site); what antibiotics are used in cellulitis prophylaxis? (2)
Penicillin V or erythromycin for up to 2 years.
State some potential acute complications of cellulitis
- Necrotising fasciitis
- Myositis
- Subcutaneous abscess
- Septicaemia
State some potential chronic complications of cellulitis
- Lymphoedema
- Recurrent cellulitis
- Chronic ulcer
What is erysipelas?
Erysipelas is a distinct form of superficial cellulitis (bacterial infection of superficial dermis) with notable lymphatic involvement. It is raised and sharply demarcated from uninvolved skin. Commonly involves face.
