Abstract Number: 24

Distinguishing lymphoedema from other forms of chronic oedema

P. Mortimer

Meeting: 2016 Dermcoll

Session Information

Date: -

Session Title: Registrars’ Teaching Session

Session Time: -

The swollen leg, and particularly the swollen red leg, is a common observation not only in skin clinics but also in medical practice generally. Deciding if chronic oedema is lymphoedema, or not, often challenges the medical practi- tioner.

All forms of chronic oedema should be considered as a failure of lymph drainage. This is because, contrary to tra- ditional teaching, all tissue fluid is drained predominantly by the lymphatic system. Therefore a build of interstitial fluid occurs either because the lymph drainage is impaired (true lymphoedema) or because lymph load (blood microvascular fluid filtration) is overwhelming the capac- ity of the lymph drainage. Increased lymph load will occur in circumstances of high venous pressure such as heart failure or venous disease, low plasma proteins or inflam- mation e.g. local dermatitis or infection. However if lymph drainage is adequate oedema should be avoided.

The clinical approach should consider factors that impair lymph drainage and increase lymph load. Reasons for chronic oedema may well be multifactorial. For example in an obese patient both the obesity and immobility will directly impair lymph drainage whereas falling asleep in a chair with legs dependent will increase fluid filtration, because of high venous pressures in the legs, and whole body fluid retention from sleep apnea syndrome.

Clinical pointers that suggest the lymph drainage is pri- marily at fault are limited improvement with overnight elevation or diuretics, associated recurrent cellulitis and skin changes i.e thickened skin and hyperkeratosis.

Treatment of the swollen limb should seek to limit lymph load, improve lymph drainage and prevent infection.