- Lymphedema
- A common chronic, debilitating condition in which excess fluid called lymph collects in tissues and causes swelling (edema) in them. Lymphedema (edema due to lymphatic fluid) may occur in the arms or legs. This often happens after lymph vessels or lymph nodes in the axilla (armpit) or groin are removed by surgery or damaged by radiation, impairing the normal drainage of lymphatic fluid. Lymphedema may also due to a mass such as a tumor pressing on the lymphatic vessels. Congenital lymphedema: In many other cases, lymphedema is evident at birth and is due to a congenital malformation (that is, a birth defect) of the lymphatic system. Congenital lymphedema can be found associated with the Noonan and Turner syndromes and a number of forms of lymphedema are clearly due to genetic factors. Genetic factors in lymphedema: Hereditary lymphedema is heterogeneous and usually occurs as an autosomal dominant trait. The most common form of congenital primary hereditary lymphedema is Milroy disease which is sometimes caused by mutations (changes) in the vascular endothelial growth factor receptor-3 gene (VEGFR-3, or FLT4) The lymphedema-distichiasis (LD) syndrome is a less common cause of hereditary lymphedema. In LD there is lymphedema (primarily of the limbs, with variable age at onset) together with distichiasis, (double rows of eyelashes). There may also be heart defects, cleft palate, extradural cysts, and photophobia. A gene for LD was mapped by linkage studies to chromosome band 16q24.3. In families with LD, mutations have been found in the FOXC2 (MFH-1) gene. FOXC2 is a member of the forkhead/winged-helix family of transcription factors, whose members are involved in diverse developmental pathways. (Fang et al. Am J Hum Genet 67:1382-1388, 2000)
* * *Swelling (especially in subcutaneous tissues) as a result of obstruction of lymphatic vessels or lymph node s and the accumulation of large amounts of lymph in the affected region. SEE ALSO: elephantiasis. [lymph + G. oidema, a swelling]- congenital l. hereditary l..- hereditary l. permanent pitting edema usually confined to the legs; two types, congenital (Milroy disease [MIM*153100], caused by mutation in the FMS-like tyrosine kinase 4 gene (FLT4) on 5q, or with onset at about the age of puberty (Meige disease [MIM*153200]); autosomal dominant inheritance.- l. praecox SYN: primary l..- primary l. a form of l. observed chiefly in young women and girls, characterized by diffuse swelling of the lower extremities. SYN: l. praecox.
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lymph·ede·ma or chiefly Brit lymph·oe·de·ma .lim(p)-fi-'dē-mə n edema due to faulty lymphatic drainage* * *
lym·phe·de·ma (lim″fə-deґmə) [lymph- + edema] chronic unilateral or bilateral edema of the limbs due to accumulation of interstitial fluid as a result of stasis of lymph, secondary to obstruction of lymph vessels or disorders of lymph nodes.
Marked lymphedema after inguinal and pelvic lymphadenectomy.
Medical dictionary. 2011.
