Cellulitis

Whetstone (Watestone), 1598.

Cellulitis, wound erysipelas, erysipelas, erysipelas, Streptodermia cutanea lymphatica.

Bacterial, dermal infection of the lymphatic clefts and vessels, which is characterised by localised redness, swelling and hyperthermia.

2 / 1000 / year, rate is increasing.

Clinical classification

• Bullous form (Erysipelas vesiculosum et bullosum)
• Phlegmonous form
• Necrotic form
• Hemorrhagic form
• Recurrent erysipelas is referred to as "recurrent erysipelas"

• Predisposing factors
  • Alcohol abuse
  • Adiposity per magna
  • Heart failure
  • Diabetes mellitus
  • Lymphatic drainage disorders (lymphoedema)
  • Patients with recent trauma (surgery, radiotherapy, fracture)
• Incubation time: 1-3 days
• 80% of all cellulitides are triggered by streptococci of groups A, B, C and G. Staphylococcus aureus, gram-negative, aerobic and anaerobic pathogens can also be causative
• The bacteria enter through defective skin sites. Entry sites are caused by a disturbed barrier function, tinea pedis, minor injuries, venous leg ulcers, trauma and chronic inflammation. In addition, up to 30% of all adults are germ carriers of Streptococcus pyogenes (nasopharynx)

• Mostly unilateral, acute dermatitis with swelling, hyperthermia, a feeling of tension, partly pressure-painful erythema or plaque with tongue-shaped irregular extensions, which spread peripherally. There is often simultaneous lymphangitis and lymphadenitis
• General symptoms include fever to 40°C and chills

• Diagnosis is made clinically
• BB (leukocytosis with neutrophilia)
• BSG (elevated), CRP (elevated)
• ASL (elevated) or ASO (elevated)-determination possible, but the relevance to therapy should be questioned
• Liver and kidney parameters (if antibiotic therapy is imminent)
• HbA1c and daily blood glucose profile in v.a. diabetes mellitus
• When body temperature is > 38°C collection of blood cultures

Mostly the lower legs are affected, but cellulitis can occur (almost) anywhere. Always look for entry points such as macerated tinea interdigitalis pedis. 

Edema of the corium and subcutis, vascular dilatations with bulging erythrocyte-filled blood vessels, sometimes erythrocyte extravasations, perivascular infiltrates of lymphocytes, inflammatory infiltrates with neutrophilic polymorphonuclear granulocytes, sometimes the detection of bacilli (Gram, Giemsa stain) is possible.

• Sinus thrombosis (facial cellulitis)
• Myo-, endo- and pericarditis
• Glomerulonephritis
• Pneumonia
• Toxic shock syndrome
• Lymphoedema
• Tissue thickening
• Deep vein thrombosis
• Macrocheilia (tapir lip)
• Chronic recurrent erysipelas due to unsanitised ports of entry
• Lymphoedema
• Chronic venous insufficiency
• Peripheral occlusive disease

Penicillin 250mg bd. can be taken orally as prophylaxis. As the main culprit of cellulitis does not develop resistance to penicillin, this strategy has been shown to be effective as long as the drug is continued. 

Risk of relapses increases with each attack of cellulitis. 

Even with antibiotic treatment, erythema can continue to spread for 24-48 hours. 

1. Blackberg A, Trell K , Rasmussen M. Erysipelas, a large retrospective study of aetiology and clinical presentation. BMC Infect Dis 2015;15:402.
2. Linke M , Booken N. Risk factors associated with a reduced response in the treatment of erysipelas. J Dtsch Dermatol Ges 2015;13:217-25.
3. Lopez FA, Lartchenko S: Skin and soft tissue infections. Infect Dis Clin North Am 20:759-772, v-vi, 2006
4. Thomas et al. Penicillin for prevention of leg cellulitis. N Engl J Med 2013; 368:1695-1703