Cellulitis + Erysipelas Flashcards
Define Cellulitis
Acute spreading infection of the skin with visually indistinct borders that principally involves the dermis and SC tissue
Define Erysipelas
Distinct form of superficial cellulitis with notable lymphatic involvement - raised and sharply demarcated from uninvolved skin
Aetiology of Cellulitis + Erysipelas
Micro-organisms gain entry to the dermal and SC tissue via disruptions in the cutaneous barrier
Beta-haemolytic streptococci and S. aureus are the most commonly implicated causative agents
Usually occurs in a host with altered immunity or due to specific exposure
Risk factors for Cellulitis + Erysipelas
Diabetes Venous insufficiency Eczema Oedema and lymphoedema Obesity Previous episodes of cellulitis Toe-web abnormalities
Symptoms of Cellulitis + Erysipelas
Cellulitis: Acute, onset of red, painful, hot, swollen skin
Erysipelas: Well-demarcated, bright-red raised skin
Blistering Bruising Fever Malaise Constitutional symptoms: rigors, nausea Orbital cellulitis: blurred or double vision
History of recent cutaneous trauma/surgery, travel
Signs of Cellulitis + Erysipelas
Cellulitis: Acute, onset of red, painful, hot, swollen skin
Erysipelas: Well-demarcated, bright-red raised skin
Bleeding -> petechiae or ecchymoses
- Superficial into blisters
- Cutaneous haemorrhage
Orange-peel appearance - peau d’orange (superficial oedema around hair follicles)
Lymphangitis (red line that spreads proximally along lymphatics towards nodes)
Lymphadenopathy
Toe-web abnormalities e.g. evidence of fungal infection (tinea)
Fluctuance deep to cellulitis (rare)
Dermal necrosis
Signs of sepsis
Orbital cellulitis: external eye muscle ophthalmoplegia proptosis, reduced acuity
Signs of necrotising fasciitis
Rapid progression and pain out of proportion to clinical signs
Skin inflammation, swelling, and dusky discoloration
Numbness
Subcutaneous tissue that feels wooden and hard, and that extends beyond the area of apparent skin involvement
High fever, disorientation, and lethargy
Crepitus, which indicates gas in the tissues
Investigations for Cellulitis + Erysipelas
Clinical diagnosis
Skin swab: useful for MRSA identification
Skin aspirate: Growth of the pathogen + antibiotic sensitivity
Skin biopsy: Growth of the pathogen, histology may show infection/inflammation
LFTs: assess for end-organ damage
Plain X-ray: may reveal underlying osteomyelitis or gas in SC tissue (If osteomyelitis or necrotising fasciitis is suspected)
MRI: Same as X-ray, may show abscess
USS: fluid collection in abscess
What are the criteria for admission with Cellulitis + Erysipelas
Are systemically unwell, with hypotension, tachycardia, or pyrexia
May have unusual organisms (e.g., immersion injury)
Are immunocompromised (Have a lower threshold for admitting these patients)
Management for acute cellulitis and erysipelas
- Empirical antibiotic therapy
- Severe -> IV flucloxacillin (unsuitable -> clarithromycin)
- Community management: IV ceftriaxone
- Eyes or nose -> oral co-amoxiclav (2nd line clarithromycin + metronidazole)
- Non-severe -> Oral flucloxacillin - Consider hospital admin based on Eron severity
- Supportive (fluids, thromboprophylaxis, wound management, monitoring (draw around infection)
- Analgesia (paracetamol, NSAIDs)
- Consider MRSA antibiotic cover (vancomycin)
What antibiotics should be used if there is cellulitis + erysipelas with the follow exposures: fresh water exposure, salt water exposure, bites
Fresh water exposure → ciprofloxacin, doxycycline, trimethroprim/sulfamethoxazole
Salt-water exposure → doxycycline 200mg orally for at least 7 days
Bites → specific antibiotics depending on animal
What is the management for frequent relapses of cellulitis and erysipelas
Manage the predisposing factors e.g. DM, venous insufficiency, oedema, obesity etc. Antibiotic prophylaxis (not routine) - phenoxymethylpenicillin
Complications of Cellulitis and erysipelas
Sepsis (Caused by vibrio vulnificus after salt water exposure, usually occurs in those with pre-existing liver disease)
Chronic oedema in affected extremity (Damage to draining lymphatics and/or veins, thereby increasing susceptibility to recurrent episodes of cellulitis) - Manage with compression stockings
Abscess
Necrotising fasciitis
Peri-orbital cellulitis - Medical emergency
Prognosis for cellulitis and erysipelas
The prognosis of cellulitis is excellent.
Most episodes of cellulitis resolve with therapy, and major sequelae are absent
However, an episode of cellulitis may leave residual damage to draining lymphatics and perhaps increase the likelihood of recurrence in the future (8-20% rate)
