What is the difference between lymphedema and lipedema?

Differences Between Lymphedema and Lipedema

Lymphedema and lipedema are distinct conditions with different pathophysiological mechanisms, clinical presentations, and management approaches, with lymphedema resulting from lymphatic system dysfunction while lipedema is an adipose tissue disorder characterized by abnormal fat deposition. 1, 2

Key Distinguishing Features

Pathophysiology

• Lymphedema: Results from impaired lymphatic drainage causing abnormal accumulation of interstitial fluid and fibroadipose tissue due to injury, infection, or congenital abnormalities of the lymphatic system 3, 1
• Lipedema: An adipose tissue disorder related to genetic factors and abnormal fat distribution, principally affecting women 2, 4

Clinical Presentation

Lymphedema

• Often unilateral (especially in secondary lymphedema) 3
• Positive Stemmer sign: inability to lift skin at the base of second toe/finger compared to contralateral limb 3, 1
• Characterized by:
  • Rapidly spreading areas of edema
  • Skin surface resembling orange peel (peau d'orange)
  • Potential vesicles, bullae, and cutaneous hemorrhage 1
• Volume increase ≥10% or circumference increase ≥2 cm compared to unaffected limb 1

Lipedema

• Bilateral and symmetric enlargement of legs and/or arms 2, 5
• Characterized by:
  • Abnormal deposition of fatty tissue from pelvis to ankles
  • Light pressure-induced or spontaneous pain 6
  • Disproportionate fat accumulation (thin upper body with enlarged lower extremities)
  • Sparing of feet (unlike lymphedema) 5
• Primarily affects women, often with onset around age 31 7

Diagnostic Findings

Lymphedema

• Gold standard diagnosis: Lymphoscintigraphy showing lymphatic system impairment 1
• Absence of visualization of inguinal lymph nodes in 14/15 cases 7
• Increased colloid half-life (230 ± 92 minutes) 7
• Decreased lymphatic speed of colloid (6.91 ± 0.86 cm/min) 7

Lipedema

• Often misdiagnosed as obesity or lymphedema 2
• Lymphoscintigraphy shows mild lymphatic insufficiency without morphologic abnormalities 7
• Moderate increase in colloid half-life (154 ± 23 minutes) compared to normal limbs but less than lymphedema 7
• Normal lymphatic speed of colloid (8.10 ± 0.45 cm/min) 7

Diagnostic Approach

For Suspected Lymphedema

1. Assess for risk factors (cancer treatment, lymph node dissection)
2. Check for Stemmer sign (thickened skin fold at base of second toe/finger)
3. Perform circumferential measurements (≥2 cm increase compared to unaffected limb)
4. Consider lymphoscintigraphy if clinical suspicion remains high despite negative Stemmer sign 3, 1

For Suspected Lipedema

1. Look for bilateral, symmetric fat deposition
2. Note sparing of feet (characteristic "cuff" at ankle)
3. Assess for pain on pressure
4. Rule out other causes of edema (cardiac, renal, hepatic) 2, 5

Management Differences

Lymphedema Management

• Complete decongestive therapy (CDT) including:
  • Manual lymphatic drainage
  • Compression therapy
  • Meticulous skin care
  • Exercise 1
• Regular monitoring for infection risk
• Compression garments during physical activity 1

Lipedema Management

• Different approach than lymphedema 2
• May include:
  • Weight management (though weight loss alone is often ineffective)
  • Liposuction and laser-assisted lipolysis
  • Pain management strategies
  • Lymphedema therapy components may help reduce pain 6

Common Pitfalls and Caveats

• Obesity may cause false-positive Stemmer sign 3
• Lipedema is frequently misidentified as obesity or lymphedema 2
• Both conditions can coexist, complicating diagnosis and treatment
• Lymphatic insufficiency may be present in lipedema without morphologic abnormalities seen in lymphedema 7
• Early intervention is crucial for both conditions to prevent progression and complications

Understanding these distinctions is essential for proper diagnosis and management, as treatment approaches differ significantly between these conditions despite their sometimes similar appearance.