Lymphedema

Definition and EtiologyTop

Lymphedema is edema involving mainly the subcutaneous tissue that develops as a result of lymph stasis caused by a congenital defect or acquired damage to the lymphatic vessels. The impaired lymph flow causes chronic inflammation of varying severity with subsequent hypertrophy of the skin and subcutaneous tissue.

Chronic lymphedema is classified as primary or secondary. Primary lymphedema is caused solely by changes in lymphatic vessels, generally due to a congenital or inherited condition, while the more common secondary lymphedema is caused by damage to the lymphatic system in the course of other diseases or treatments. Classification and causes of lymphedema: Table 1.

Clinical FeaturesTop

Secondary lymphedema (eg, following lymphadenectomy or infection) usually develops after a few months or even years of a latency period. Initially it presents as pitting edema but typically hardens and becomes nonpitting with time due to fibrosis. Lymphedema usually begins distally and progresses proximally. However, in patients with damage to the proximal lymphatic system, lymphedema may affect only the proximal portion of an extremity and an adjacent quadrant of the trunk (eg, arm and/or breast lymphedema following lymphadenectomy due to breast cancer, thigh and/or external genitalia lymphedema after lymphadenectomy due to urogenital or gynecologic cancer; Figure 1). Depending on the cause, lymphedema may be unilateral or bilateral.

Progression of lower limb lymphedema eventually causes massive edema of the dorsum of the feet (Buffalo hump sign) and swelling of the toes (squaring toes sign). Hardening of the skin of the forefoot causes inability to pinch and lift the skin at the base of the second toe (Stemmer sign).

Clinical stages of lymphedema based on the International Society of Lymphology (ISL) system:

– Stage 0: Impaired lymph flow without visible edema.

– Stage 1: Edema resolves after limb elevation or overnight rest.

– Stage 2: Edema does not resolve completely after limb elevation.

– Stage 3: Sustained edema with trophic skin changes and deformation of the limb.

DiagnosisTop

In the majority of cases diagnosis is based on clinical manifestations. If necessary, perform lymphoscintigraphy. Ultrasonography, magnetic resonance imaging (T2-weighted MRI), computed tomography (CT), or radioactive isotope studies may be useful in diagnosis.

Differential diagnosis includes lipedema (mostly in women; symmetric accumulation of fat in the legs sparing the feet [“column-like legs”]), edema due to chronic venous insufficiency, positional edema as a result of prolonged sitting or standing in individuals without venous insufficiency, myxedema in patients with hypothyroidism, pretibial myxedema in patients with Graves disease, idiopathic cyclic edema, edema in patients with advanced heart failure or hypoalbuminemia, enlargement of the limbs due to tumors, postthrombotic syndrome, and limb hypertrophy.

TreatmentTop

The key treatment method is comprehensive therapy consisting of skin and wound care, compression therapy, and lymphatic drainage using decompression exercises and massage-like techniques by physiotherapists. Patients should also be advised on maintaining ideal body weight, limb elevation, and avoiding prolonged limb placement in a gravity-dependent position. Exercise is generally safe and should be allowed with compression garments. Compression therapy is highly recommended using compression bandages, compression garments, and intermittent pneumatic compression.

In addition to good skin hygiene and avoidance of injuries, chronic suppressive antibiotic therapy for several months or years may be warranted to prevent recurrent infection (clinical experience only). Common regimens include IM benzathine penicillin G (INN benzathine benzylpenicillin) 1.2 million IU every 2 to 4 weeks for prevention of beta-hemolytic streptococcal infection and oral trimethoprim/sulfamethoxazole double strength bid for prevention of staphylococcal infection. Some other regimens include erythromycin or cephalexin.

In patients not responding to compression therapy, surgical intervention such as liposuction, lymphatic bypass procedures, and vascularized lymph node transfer can be helpful. Contraindications to surgery include acute cellulitis, recent deep vein thrombosis of the lower limbs, and decompensated congestive heart failure.

ComplicationsTop

1. Recurrent infections (eg, cellulitis, lymphangitis, and tinea pedis in between toes).

2. Disfiguration of the affected limb and elephantiasis.

3. Recurrent and difficult to treat ulcers of the affected limbs, mostly legs.

4. Colonization with bacteria and fungi resulting in chronic malodorous limbs.

5. Elephantiasis nostras verrucosa presenting as thick verrucous changes on top of fibrotic changes of legs.

6. Reduced limb function in severe cases.

Tables and FiguresTop

Figure 3.13-1. Lymphedema of the left arm 7 years after left breast cancer mastectomy and left axillary lymph node dissection.