[10] Cellulitis Flashcards
What is cellulitis?
A bacterial infection involving the dermis and subcutaneous fat
What causes cellulitis?
Bacteria entering the skin
How can bacteria enter the skin?
Via a cut, abrasion or break in the skin
What are the most common causative bacteria in cellulitis?
- Group A strep
- Staphylococcus
What are the risk factors for cellulitis?
- Immunocompromisation
- Previous erysipelas or cellulitis
- Venous insufficiency
- Elderly age
- Alcoholism
- IV drug use
- Overweight/obesity
Where is cellulitis most commonly seen?
In the lower limbs unilaterally
How does skin affected by cellulitis appear?
Erythema, pain, swelling and warmth of affected skin
What are the systemic symptoms of cellulitis?
Fever and malaise
What is seen in cellulitis that has progressed to the lymphatic system?
Red lines streaking away from the cellulitic area
How can cellulitis be differentiated from erysipelas?
Cellulitis has poorly demarcated borders compared to the sharp borders of erysipelas
How is cellulitis diagnosed?
Clinically
What investigation may be required in atypical, refractive or serious cases of cellulitis?
Swabs from potential portals of entry
What other investigations could be considered in cellulitis if concerned about a foreign body in situ or bone involvement?
- X-rays
- CT scans
- MRI (not if metal foreign body)
If bullae or abscesses form in cellulitis what investigation can be performed?
Culture of fluids
What investigations may be required in recurrent episodes of cellulitis?
Investigations to exclude underlying causes e.g. DM or immunodeficiency
What are the differentials for cellulitis?
- Necrotising fasciitis
- Superficial thrombophlebitis
- DVT
- Gout
- Dermatitis
- Varicose eczema
What are the general supportive management options in cellulitis?
- Rest
- Elevate affected limb
- Analgesia
- Manage underlying conditions
- Clean any wound sites
- Use emollients
What is the first line antibiotic in uncomplicated cellulitis?
Flucloxacillin 500mg QDS
What antibiotic can be given for cellulitis in patients with penicillin allergy?
Erytromycin 500mg QDS
What antibiotic is often given as second-line in cellulitis?
Clindamycin
How long is antibiotic therapy given for?
7 days (increase to 10-14 if needed)
When should patients with cellulitis be referred to hospital?
- Rapidly worsening infection
- Systemic illness or vomiting
- Facial infection
- Immunocompromised
- Under 1 year old
What are the potential complications of cellulitis?
- Abscess formation
- Fasciitis
- Sepsis
- Thrombophlebitis/lymphangitis
- Necrotising fasciitis
- Osteomyelitis
