Cellulitis is a common bacterial skin infection that affects the deeper layers of the skin and the subcutaneous tissues. It typically occurs when bacteria enter the skin through a break or crack, causing redness, swelling, and pain. Cellulitis can occur anywhere on the body and may spread rapidly if left untreated.
Ludwig’s Angina - cellulitis of the submandibular space (often after dental procedures)
Causes/Factors
Most common bacteria - Strep. pyogenes and Staph. aureus
- Skin Injuries: Cuts, wounds, insect bites, or surgical incisions.
- Skin Conditions: Atopic dermatitis (eczema), dermatitis, or other pre-existing skin disorders.
- Weakened Immune System: Conditions like Diabetes Mellitus or immunodeficiency.
- Lymphedema: Swelling that impairs the normal flow of lymph.
Symptoms
- Demarcation: Well-defined borders between affected and unaffected skin.
- Systemic Symptoms: Fever and generalized malaise.
- Lymphangitis: Red streaks indicating spread along lymph vessels.
Signs
- Calor, dolor, rubor, tumor (heat, tenderness, erythema, swelling)
- Fever and Chills: if septic
- Skin Lesions: Blistering or oozing of clear fluid.
Diagnostic Tests
Diagnosing Cellulitis is primarily based on clinical evaluation, but additional tests may be used to exclude a Deep Vein Thrombosis:
- FBC, CRP and possible imaging
Management
- Elevate affected limb
- Antibiotics (PO/IV dependant on severity) - commonly Amoxicillin / ben pen + flucloxacillin. If penicillin allergic - Clindamycin and ceftriaxone. 10 day course PO but up to 14 days IV if systemic.
Complications/red Flags
- Septicaemia
- Abscess formation
- Recurrence
- Chronic skin discolouration