Editing 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

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

[[Category:Vascular]]