Facial Cellulitis

Facial cellulitis is acute bacterial infection of the skin and subcutaneous tissue of the face, caused by beta haemolytic streptococci (erysipelas) and Staphylococcus aureus. Venous drainage of the central face to the cavernous sinus makes infection of the nose, upper lip and eyelids potentially dangerous.

• Entry points: nasal vestibulitis, sinusitis, dental infection, skin trauma, insect bites, eczema, tinea, piercing, squeezing of facial boils.
• Risk factors: diabetes, immunosuppression, previous erysipelas, lymphoedema.

Painful, warm, sharply demarcated erythema and swelling (erysipelas: raised border, butterfly distribution over cheeks and nose), fever, chills, malaise, regional lymphadenopathy.

• Eyelid oedema, proptosis, ophthalmoplegia, headache, confusion suggest orbital or cavernous sinus extension.
• Differential diagnosis: contact dermatitis, herpes zoster, angioedema, allergic reaction, rosacea, lupus erythematosus, dental abscess, sinusitis, periorbital cellulitis, necrotising fasciitis, herpes simplex.
• Complications: facial abscess, orbital cellulitis, cavernous sinus thrombosis, meningitis, brain abscess, bacteraemia, necrotising fasciitis, scarring, recurrence.

Clinical.

• Full blood count, CRP, blood cultures (febrile or systemic); swab of pus or skin breaks.
• CT with contrast or MRI/MRV if orbital signs, severe headache, or neurological features.
• Dental examination and sinus imaging if source suspected; glucose and HIV test.

Antibiotics against streptococci and staphylococci, with admission for high risk presentations.

• Supportive: cold compress, head elevation, analgesia (paracetamol 1 g every 6 hours), fluids, avoid squeezing or manipulating, outline the border with a pen to monitor spread.
• Pharmacological: flucloxacillin 500 mg to 1 g four times daily for 7 to 10 days (children 12.5 to 25 mg/kg four times daily); erysipelas: phenoxymethylpenicillin 500 mg four times daily for 7 to 10 days; penicillin allergy: clindamycin 300 to 450 mg three times daily or doxycycline 100 mg twice daily. Severe or systemic: flucloxacillin 2 g IV every 6 hours with benzylpenicillin 1.2 g IV every 6 hours; MRSA risk: vancomycin 15 to 20 mg/kg IV every 12 hours. Cavernous sinus thrombosis: ceftriaxone 2 g IV every 12 hours with vancomycin and metronidazole 500 mg IV every 8 hours for 3 to 4 weeks, with heparin anticoagulation under specialist guidance. Tetanus toxoid if needed.
• Procedures: drainage of facial abscess; dental extraction or sinus drainage when source; nasal vestibule decolonisation with mupirocin 2 percent twice daily for 5 days in recurrent staphylococcal cases.
• Special groups: pregnancy, flucloxacillin or penicillin V; children, early admission for periorbital involvement; diabetes, strict glucose control; HIV, treat HIV and consider resistant organisms.
• Red flags: eyelid swelling with pain on eye movement, proptosis, vision change, severe headache, drowsiness, nuchal rigidity, rapid spread, fever above 39 degrees Celsius, toxic appearance.
• Follow-up: review at 24 to 48 hours; extend therapy for slow response; prevent recurrence by treating tinea, eczema and nasal carriage.