CELLULITIS
A complete clinical guide covering causes, pathogenesis, symptoms, diagnosis, treatment, nursing interventions, complications, and prevention.
What is Cellulitis?
Cellulitis is an acute bacterial infection involving the skin and subcutaneous tissues. It most commonly affects the lower limbs but may occur anywhere on the body. The infection develops when bacteria penetrate through a break in the skin and spread through the dermis and underlying tissues.
Most Common Organisms:
Streptococcus pyogenes and Staphylococcus aureus are responsible for the majority of cellulitis cases.
Causes of Cellulitis
- Cuts and lacerations
- Surgical wounds
- Burns
- Insect bites
- Animal bites
- Skin ulcers
- Cracked skin
- Eczema and psoriasis
- Athlete's foot (Tinea pedis)
How Cellulitis Develops (Click Each Step)
Skin Barrier Breakdown
Bacterial Entry
Bacterial Multiplication
Inflammatory Response
Tissue Damage
Spread of Infection
A cut, wound, insect bite, surgical incision, or skin disease compromises the skin's protective barrier.
Bacteria enter through the damaged skin and reach the dermis and subcutaneous tissue.
The organisms multiply rapidly within the tissue, increasing the bacterial load.
The immune system responds by releasing inflammatory mediators, causing redness, heat, pain, and swelling.
Inflammation causes tissue edema and may impair blood supply to affected areas.
If untreated, infection may spread through lymphatic channels, bloodstream, or deeper tissues.
Who is at Risk?
Medical Conditions
Diabetes mellitus, obesity, peripheral vascular disease, and immunosuppression.
Skin Disorders
Eczema, psoriasis, fungal infections, and chronic wounds.
Previous Infection
Patients with a history of cellulitis are at increased risk of recurrence.
Signs and Symptoms
- Redness of affected skin
- Localized swelling
- Pain and tenderness
- Warm skin
- Fever
- Chills
- Fatigue
- Pus formation
- Enlarged lymph nodes
Seek urgent medical attention if:
The redness spreads rapidly, blisters develop, high fever occurs, or signs of sepsis appear.
Diagnosis
- Clinical examination
- Complete Blood Count (CBC)
- Blood cultures
- Wound swab culture
- CRP and ESR
- Ultrasound if abscess is suspected
Management of Cellulitis
Antibiotic Therapy
| Drug | Common Adult Dose |
|---|---|
| Flucloxacillin | 500 mg–1 g orally every 6 hours |
| Cephalexin | 500 mg orally every 6 hours |
| Clindamycin | 300–450 mg orally every 6 hours |
| Vancomycin | IV dosing based on weight and renal function |
Supportive Care
- Rest
- Elevation of affected limb
- Adequate hydration
- Pain management
- Wound care
Nursing Interventions
- Monitor vital signs
- Assess wound appearance regularly
- Administer prescribed antibiotics
- Provide pain relief
- Perform aseptic wound care
- Educate patient on medication adherence
- Promote rest and comfort
- Monitor for complications
Potential Complications
- Abscess formation
- Sepsis
- Necrotizing fasciitis
- Osteomyelitis
- Lymphangitis
- Recurrent cellulitis
How to Prevent Cellulitis
- Practice good hygiene
- Treat cuts promptly
- Control diabetes effectively
- Use protective footwear
- Manage chronic skin conditions
- Maintain healthy body weight