Lymphedema

Occurs when there is impaired uptake of lmphatics
- increases interstitial oncotic pressures and perpetuates egress of lymph fluid
- remaining lymphatics dilate and develop valvular incompetence over time
- fibrosis of lymphatic walls eventually obilterates lymphatic channels

Skin thickens over time if lymphedema is not treated
- epidermis develops thick scaly deposits
- cracks in thickened epidermis can lead to cellulitis/lymphangitis
- may progress to malignant degeneration to lymphoscarcoma (rare): Stewart-Treves syndrome
- Lymphoscarcoma presents with reddish-purple discoloration or nodule, tends to form satellite lesions
- treatment of lymphosarcoma involves radical amputation, poor prognosis


Stewart-Treves Syndrome

Etiology:
- primary vs. secondary

Primary:
- all types more common in females
- Lymphedema I (Millroy's disease): present at birth, affects dorsum of foot, not typically progressive
- Lymphedema II (Lymphadema Praecox/Meige's disease): onset at puberty, most common form of lymphedema (65-80%). Affects lower extremities, unilateral.  Peripheral lymphatics are hypoplastic.
- Lymphedema III (lymphedema tarda): presents in midlife (>35yo).  Lower extremities.

Secondary:
- infection, cancer, morbid obesity
- worldwide, most common cause is infection with parasite (Wuchereria bancrofti)

Diagnosis:
- basic history and physical
- rule out other causes of lymphedema (cardiac, venous, renal, hepatic, iliac compression)
- if imaging desired then lymphoscintigraphy can be used to demonstrate decrerased clearance of lymph

Treatment:
conservative management predominates
- stop the positive feedback cycle of inflammation, infection and fibrosis
- skin hygeine, treatment of infection
- massage protocols to decompress limb followed by compression stockings if arterial supply is sufficient

medical treatment is limited:
- Abx to treat infection
- use of diuretics and benzopyrene (increase proteolysis in edema) are of questionable benefit

surgical management is described but rarely of benefit:
- debulking procedures (reduce size and weight of limb) - however, will also disrupt what lymph channels remain
- physiologic procedures attempt to reestablish lymphatic flow - long-term outcomes not good overall.