Erysipelas is a superficial skin infection of the upper dermis and its lymph vessels, usually caused by group A streptococcus. It often affects the legs or face and starts quickly with fever and a bright red, sharply bordered patch.
Key symptoms
- Sudden fever, chills and feeling unwell, sometimes before the rash
- Bright red, hot, painful patch of skin
- Swelling of the leg or face
- A possible entry point: a cut, athlete's foot or a leg ulcer
What you find on exam
- Raised, shiny plaque with a sharp, clearly defined border
- Ear involvement (Milian ear sign) helps separate it from cellulitis on the face
- Tender, swollen nearby lymph nodes; sometimes blisters
- Vital signs to look for sepsis
Tests
- Clinical diagnosis
- Blood count and CRP if the patient is systemically ill
- Blood cultures if severe, immunosuppressed or not improving
Treatment basics
- Oral penicillin V or amoxicillin; cephalexin as an alternative
- IV penicillin G or cefazolin if severe or unable to take pills
- Penicillin allergy: clindamycin or another option based on the type of reaction
- Raise the limb; treat athlete's foot and leg edema to prevent recurrence
- Usually 5 days of antibiotics, longer if improvement is slow
Red flags
- Pain out of proportion, dusky skin or crackling (necrotizing infection)
- Low blood pressure, confusion or other signs of sepsis
- Facial erysipelas with eye swelling or vision changes
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.