What are the characteristic skin findings in a patient with a swollen leg due to lymphedema complicated by signs of infection, including diffuse green discharge and redness?

Skin Findings in Lymphedema Complicated by Infection

The skin should be described as demonstrating cellulitis with purulent discharge (green exudate) overlying chronic lymphedematous changes, requiring immediate assessment for necrotizing infection and initiation of MRSA-active antibiotics. 1

Primary Skin Descriptors

Acute Infectious Changes:

• Erythema extending from the wound or affected area, measured in centimeters from the margin 1
• Purulent discharge (the "green stuff") indicating bacterial infection requiring culture 1
• Local warmth (calor) as a cardinal sign of inflammation 1
• Edema and induration (swelling or tumor) beyond baseline lymphedematous changes 1
• Local tenderness (dolor) on palpation 1

Chronic Lymphedematous Changes:

• Peau d'orange appearance - dimpling of skin resembling orange peel due to superficial edema surrounding hair follicles tethered to underlying dermis 1
• Woody-hard subcutaneous tissues if necrotizing fasciitis is developing (critical to assess, as this distinguishes superficial from deep infection) 1
• Chronic skin changes including thickening, fibrosis, and possible nodular changes from long-standing lymphatic dysfunction 2, 3
• Hyperkeratosis and papillomatosis in advanced cases 4

Critical Assessment Points

Distinguish Cellulitis from Necrotizing Infection:

• In cellulitis, subcutaneous tissues remain yielding and palpable on examination 1
• In necrotizing fasciitis, tissues feel wooden-hard and fascial planes cannot be discerned by palpation 1
• Look for skin anesthesia, bullous changes, or rapid progression suggesting deeper infection requiring emergent surgical consultation 1, 5

Assess Infection Severity (IWGDF/IDSA Classification):

• Measure erythema extension: <2 cm = mild infection; ≥2 cm = moderate infection 1
• Check for systemic signs: temperature >38°C or <36°C, heart rate >90 bpm, respiratory rate >20 breaths/min indicating severe infection 1
• Document presence of purulent secretions, necrosis, or friable granulation tissue 1

Underlying Lymphedema Features

Pre-existing Lymphatic Dysfunction:

• The lymphedema itself represents subclinical lymphatic impairment that predisposes to infection 6
• Patients often have bilateral lymphatic dysfunction even when swelling appears unilateral 6
• Chronic edema causes permanent lymphatic damage with each infectious episode 1

Associated Skin Breakdown:

• Examine interdigital toe spaces for maceration, fissuring, scaling, or tinea pedis as bacterial entry points 1, 5
• Look for venous eczema (stasis dermatitis) or other inflammatory dermatoses 1
• Document any ulceration or trauma that disrupted the skin barrier 1

Documentation Template

Describe systematically:

1. Extent of erythema (measure in cm from wound/affected area margin) 1
2. Character of discharge (purulent/green indicating bacterial infection vs. clear/chylous from lymphatic leakage) 1, 7
3. Tissue consistency (yielding vs. wooden-hard) 1
4. Baseline lymphedematous changes (peau d'orange, chronic thickening, nodularity) 1, 4
5. Systemic signs (fever, tachycardia, altered mental status) 1
6. Predisposing factors (toe web abnormalities, venous insufficiency) 1

Common Pitfalls

• Do not dismiss green discharge as "just lymphedema" - this represents bacterial infection requiring cultures and antibiotics 1
• Do not assume bilateral swelling excludes infection - lymphedema patients have heightened infection susceptibility in both limbs 6, 3
• Do not delay surgical consultation if any wooden-hard texture, severe pain, or rapid progression suggests necrotizing infection 1, 5
• Do not overlook toe web spaces as the source of streptococcal entry in lower extremity infections 1, 5