Erysipelas and cellulitis


Acute skin infections, most often due to Group A beta-haemolytic streptococcus, and at times Staphylococcus aureus (including methicillin resistant S. aureus–MRSA). Recurrence is common in adults.

Clinical signs

– Skin erythema, oedema with well demarcated margins, warmth, pain, usually on the lower limbs and at times the face.
– Often with fever, lymphadenopathy and lymphangitis.
– Look for a portal of entry (bite, ulcer, wound, intertrigo, eczema, fungal infection, etc.).
– Rarely progression to necrotising fasciitis (Chapter 10).
– Rare systemic complications: septicaemia, acute glomerulonephritis.

Treatment

– In all cases:
• Outline the area of erythema with a pen in order to follow the infection1 .
• Bed rest with leg elevated, treatment of pain (Chapter 1).
• Administer antibiotics: either orally or IV depending on severity.
• Treat portal of entry.
• Non-steroidal anti-inflammatory drugs are contra-indicated (risk of necrotizing fasciitis).
• Test for proteinuria by urine dipstick, 3 weeks after infection in order to detect glomerulonephritis.
• Tetanus immunisation: see Tetanus (Chapter 7).

– Hospitalize for the following: children younger than 3 months, critically ill appearing patient2 , local complications, debilitated patient (chronic conditions, the elderly) or if there is a risk of non-compliance with or failure of outpatient treatment. Treat other patients as outpatients.

– Outpatient antibiotherapy3 :
cefalexin PO for 7 to 10 days
Children 1 month to 12 years: 25 mg/kg 2 times daily
Children 12 years and over and adults: 1 g 2 times daily
or
amoxicillin/clavulanic acid (co-amoxiclav) PO for 7 to 10 days
Use formulations in a ratio of 8:1 or 7:1. The dose is expressed in amoxicillin:
Children < 40 kg: 25 mg/kg 2 times daily
Children ≥ 40 kg and adults: 
Ratio 8:1: 2000 mg daily (2 tablets of 500/62.5 mg 2 times daily)
Ratio 7:1: 1750 mg daily (1 tablet of 875/125 mg 2 times daily)

– Inpatient antibiotherapy4 :

• First line therapy:
cloxacillin IV infusion over 60 minutes5
Children 1 month to 12 years: 12.5 to 25 mg/kg every 6 hours
Children over 12 years and adults: 1 g every 6 hours 
or
amoxicillin/clavulanic acid (co-amoxiclav) by slow IV injection (3 minutes) or infusion (30 minutes). The dose is expressed in amoxicillin:
Children under 3 months: 30 mg/kg every 12 hours 
Children 3 months and over: 20 to 30 mg/kg every 8 hours (max. 3 g daily)
Adults: 1 g every 8 hours
If there is clinical improvement after 48 hours (afebrile and erythema and oedema have improved) switch to cefalexin or amoxicillin/clavulanic acid PO at the doses indicated above to complete 7 to 10 days of treatment.

• If there is no clinical improvement after 48 hours, consider MRSA:
clindamycin IV infusion over 30 minutes6
Children 1 month and over: 10 mg/kg every 8 hours
Adults: 600 mg every 8 hours
After 48 hours, change to clindamycin PO at the doses indicated above to complete 7 to 10 days of treatment.

• In case of necrotizing fasciitis: urgent transfer to a surgical centre, initiate antibiotic therapy while awaiting transfer.



Footnotes
Ref Notes
1 The erythema will regress if the treatment is effective. If the erythema spreads consider a treatment failure (MRSA or a necrotizing infection).
2 Critically ill appearing child: weak grunting or crying, drowsy and difficult to arouse, does not smile, disconjugate or anxious gaze, pallor or cyanosis, general hypotonia.
3 For penicillin-allergic patients, clindamycin PO for 7 to 10 days (children: 10 mg/kg 3 times daily; adults: 600 mg 3 times daily).
4 For penicillin-allergic patients, clindamycin IV infusion (doses as above).
5 Cloxacillin powder for injection should be reconstituted in 4 ml of water for injection. Then dilute each dose of cloxacillin in 5 ml/kg of 0.9% sodium chloride or 5% glucose in children less than 20 kg and in a bag of 100 ml of 0.9% sodium chloride or 5% glucose in children over 20 kg and in adults.
6 Dilute each dose of clindamycin in 5 ml/kg of 0.9% sodium chloride or 5% glucose in children less than 20 kg and in a bag of 100 ml of 0.9% sodium chloride or 5% glucose in children over 20 kg and in adults.