What is the difference between erysipelas and cellulitis?

From the Guidelines

Erysipelas and cellulitis are distinct bacterial skin infections that differ in their depth and presentation, with erysipelas affecting the upper dermis and superficial lymphatics, and cellulitis involving the deeper dermis and subcutaneous fat. The key differences between erysipelas and cellulitis lie in their clinical presentation and the depth of skin involvement. Erysipelas is characterized by a well-demarcated, raised, bright red, painful rash with a clear border between infected and normal skin, commonly occurring on the face and legs, and often accompanied by fever and systemic symptoms 1. In contrast, cellulitis involves the deeper dermis and subcutaneous fat, appearing as a less defined, spreading area of redness, warmth, pain, and swelling without the raised edges characteristic of erysipelas, with a typically blurry border between infected and normal skin 1. Some key points to consider when differentiating between erysipelas and cellulitis include:

• The depth of skin involvement, with erysipelas affecting the upper dermis and superficial lymphatics, and cellulitis involving the deeper dermis and subcutaneous fat 1
• The presence of a clear border between infected and normal skin in erysipelas, versus a blurry border in cellulitis 1
• The common causes of each condition, with erysipelas typically caused by streptococcal species, and cellulitis caused by streptococci and Staphylococcus aureus 1
• The treatment approaches for each condition, which typically involve antibiotics such as penicillin, amoxicillin, or cephalexin for 7-10 days, with more severe cases requiring intravenous antibiotics 1. The most recent and highest quality study recommends that impetigo, erysipelas, and cellulitis should be managed by antibiotics against Gram-positive bacteria, with empiric therapy for community-acquired MRSA recommended for patients at risk or who do not respond to first-line therapy 1.

From the Research

Difference between Erysipelas and Cellulitis

• Erysipelas is a form of cellulitis with marked superficial inflammation, typically affecting the lower limbs and the face 2, 3.
• Cellulitis is a common problem caused by spreading bacterial inflammation of the skin, with redness, pain, and lymphangitis, and can result in local necrosis and abscess formation 2, 3.
• Erysipelas is usually caused by Group A Beta-hemolytic streptococcus (GABHS, Streptococcus pyogenes), while cellulitis can be caused by streptococci and Staphylococcus aureus 4, 2.
• Patients with erysipelas typically have a well-demarcated, erythematous, indurated, rapidly spreading patch with a palpable advancing border on the face or extremities, accompanied by fever, chills, and general malaise 4.
• Cellulitis and erysipelas can have similar symptoms, but erysipelas tends to have more pronounced superficial inflammation and a more defined border 2, 3.

Clinical Characteristics

• Erysipelas often affects the face or extremities, while cellulitis can affect any part of the body 4, 2.
• Erysipelas tends to have a more rapid onset and progression than cellulitis 4.
• Both conditions can lead to complications such as abscess formation, necrotizing fasciitis, septicemia, and lymphedema 4, 2.

Treatment and Prevention

• Antibiotics are usually effective in treating both erysipelas and cellulitis, but the choice of antibiotic may depend on the suspected causative organism 4, 2.
• Treatment of predisposing factors, such as diabetes mellitus and immunocompromised states, is also important in preventing recurrence of cellulitis and erysipelas 2, 3.
• The need for empirical coverage of Staphylococcus aureus in cellulitis/erysipelas is still a topic of debate, with some studies suggesting that it may not be necessary for most patients 5.