Lymphedema - Causes and Symptoms

Definition

Lymphedema is an accumulation of lymph in various districts of the body, often due to an anomaly of the lymphatic system.

Lymph is an interstitial fluid that circulates in the lymphatic vessels and plays an important role in the immune system; in fact, thanks to the presence of circulating lymphocytes in suspension, the lymph responds to signs of damage or infection.

Lymphedema is an edema (swelling) that is not compressible and has a fibrous consistency; among the symptoms there may be pain and fatigue in the affected limbs.

Lymphedema can be primitive or secondary.

Primitive lymphedemas are rare and hereditary; in general, they are due to congenital anomalies affecting the lymphatic system (aplasia or lymphatic hypoplasia). The disease occurs at different ages and with variable phenotypic characteristics: early and late congenital forms can be distinguished. Some examples are Milroy's disease (congenital lymphedema due to genetic mutations of the VEG endothelial growth factor receptor VEGFR-3) and Meige's disease.

Secondary lymphedema is more frequent than the primitive form and indicates the presence of acquired dysfunction of the lymphatic vessels. In many cases, it is due to an obstacle or obstruction that prevents the flow of lymph; for example, it may result from surgical interventions (eg lymphadenectomy to remove tumor masses) or radiotherapy (especially on axillary or inguinal lymph node areas) performed due to a neoplastic disease. Furthermore, it can result from trauma, tumors, severe burns, adenopathies, diabetes, lymphangitis, bacterial cellulitis, erysipelas and lymphatic filariasis.

In subjects suffering from chronic venous insufficiency, mild to moderate lymphedema may also result from transudation of lymph into interstitial tissues.