Lymphoedema

The progressive accumulation of protein-enriched interstitial fluid

Pathophysiology

• Caused by relative impairment of lymphatic vascular function
• Most common in upper or lower extremity
• High-input lymphoedema - increased venous capillary pressure leads to increased production of interstitial fluid, which can exceed the transport capacity of lymphatic conduits
• Low-output lymphoedema - compromised lymphatic flow
• Tendency for these processes to lead to progressive subcutaneous fibrosis

Aetiology

• Primary
  • Much more common in females
  • Often unilateral
  • See below for age-related classification
  • Congenital <1yo - Milroy's disease
    • Congenital absence, defective function or obstruction of lymphatics
    • One or both lower limbs
  • Lymphoedema praecox <35yo
    • The most common form of primary lymphoedema, usually involving only calf and foot, usually unilateral, and typically beginning at puberty
  • Lymphoedema tarda >35yo
• Secondary
  • Surgery
  • Cancer - related to treatment and following factors - most common in developed world
    • Obesity
    • Extent of surgery
    • Delayed wound healing
    • Post-op infection
    • Haematoma/seroma
  • Filariasis
    • Infestation with parasites (Wucheria bancrofti, Brugia malayi, Brugia timori)
    • Most common cause in developing countries
    • Transmitted by mosquitos - adult worm lives in nodes and releases larvae at night - followed by fibrosis of nodes and elephantiasis
    • Rapidly develops into elephantiasis - extremely difficult to treat
  • Burns
  • Large/circumferential extremity wounds
  • Pregnancy
  • Bacterial/fungal infections
  • Infections after snake or insect bites
  • Contact dermatitis
  • Rheumatoid arthritis

Presentation

• Pitting oedema, which usually decreases with elevation
• Oedema involving feet
• Skin changes
  • Early, pinkish colour with mildly elevated temperature
  • Later, thick skin with areas of hyperkeratosis, lichenification, and development of peau d'orange - 'pigskin'
  • Small vessels discharging lymph/chyle
• Pain - dull ache. If pain is severe, suspect infection of neuritic pain in the area of scar tissue/radiation treatment.

Complications

• Infection - the accumulated fluid and protein provides an excellent substrate for infection. Lifetime prevalence of cellulitis is 35%.
  • Most commonly beta-haemolytic Strep
  • Flucloxacillin is appropriate coverage
  • Consider MRSA
• Malnutrition and immunodeficiency
• Malignant tumours - lymphangiosarcoma

Differential diagnosis

• Venous insufficiency has distinct skin changes - haemosiderin, varicosity, pigmentation, induration, venous ulcers
  • There is often a mixed venous-lymphatic picture due to the lymphoedema secondary to venous disease
  • Lymphoedema is usually painless, but chronic venous disease often gives pain and cramps after prolonged standing/sitting or at the end of the day
• Systemic causes
  • CCF
  • Chronic constrictive pericarditis
  • Severe tricuspid regurgitation
  • Hepatic or renal failure
  • Hypoproteinaemia
  • Malnutrition
  • Endocrine disorders
  • Corticosteroid use

Diagnosis

• Use limb circumference to document and stage vs normal limb
• Bio-impedance testing uses resistant to current to diagnose lymphoedema early

Workup

• Bloods for renal and hepatic failure and eosinophilia
• Consider systemic causes for investigation
• Chronic venous disease scan
• Consider CT to exclude malignant obstruction/retroperitoneal fibrosis

Can also do:

• Technetium (Tc 99) lymphoscintigraphy to assess baseline extent of lymphatic flow obstruction.
• Indocyanine green lymphangiography to assess superficial lymph drainage/blocked lymphatic for bypass.
• MR lymphangiography can evaluate honeycombing of tissues in patients with stage II/III lymphoedema.

Mechanical reduction

• Complex decongestive therapy
  • Components:
    • Manual lymphatic drainage (gentle massage to affected areas and draining areas)
    • Compression bandaging
    • Compression garments
    • Compression devices
  • Phases:
    • Initially, the reductive phase - reduce the size of the affected area and emphasise proper skincare
    • Maintenance phase - maintain the gains made in phase 1, which requires life-long work

Surgical treatment

• Must demonstrate compliance to nonsurgical treatment
• Optimise weight
• Must have complete and competent venous system in limb
• Must be free of infection

1. Excisional procedures - remove deposited fibrofatty tissue and fluid, but don’t affect lymphatics (e.g. liposuction)
   1. Must continue lifelong compression afterwards)
2. Physiologic procedures
   1. Lymphovenous bypass
   2. Vascularised lymph node transfer
3. Preventive procedures
   1. Lymphatic microsurgery performed at time of initial surgery