Stages of Lymphedema
STAGES OF LYMPHEDEMA
Whether primary or secondary, lymphedema develops in stages, from mild to severe. Methods of staging are numerous and inconsistent. They range from three to as many as eight stages.
The most common method of staging was defined by the Fifth WHO Expert Committee on Filariasis:
Stage 0 (latent):
· The lymphatic vessels have sustained some damage which is not yet apparent.
· Transport capacity is still sufficient for the amount of lymph being removed.
· Lymphedema is not present.
Stage 1 (spontaneously reversible):
· Tissue is still at the "pitting" stage: when pressed by the fingertips, the affected area indents and holds the indentation.
· Usually upon waking in the morning, the limb or affected area is normal or almost normal in size.
Stage 2 (spontaneously irreversible):
· Tissue has a spongy consistency and is "non-pitting”: when pressed by the fingertips, the tissue bounces back without any indentation.
· Fibrosis found in Stage 2 Lymphedema marks the beginning of the hardening of the limbs and increasing size.
Stage 3 (lymphostatic elephantiasis):
· A swelling is irreversible and usually the limb(s) or affected area is (are) very large.
· Tissue is hard (fibrotic) and unresponsive.
A new staging system has been set forth by Lee, Morgan and Bergan and endorsed by the American Society of Lymphology. This provides a clear technique which can be employed by clinical and laboratory assessments to more accurately diagnose and prescribe therapy for lymphedema. In this improved version, there are four stages identified (I-IV). Physicians and researchers can utilize additional laboratory assessments such as bioimpedance, MRI, or CT to build on the findings of a clinical assessment (physical evaluation). From this, results of therapy can be accurately determined and reported in documentation as well as research.
Risk is another measurement altogether. Current research using bioimpedance to measure risk of lymphedema is very promising.
Lymphedema can also be categorized by its severity (usually referenced to a healthy extremity):
Grade 1 (mild edema):
· Lymphedema involves the distal parts such as a forearm and hand or a lower leg and foot.
· The difference in circumference is less than 4 centimeters, and other tissue changes are not yet present.
Grade 2 (moderate edema):
· Lymphedema involves an entire limb or corresponding quadrant of the trunk.
· Difference in circumference is more than 4, but less than 6 centimeters.
· Tissue changes, such as pitting, are apparent.
· The patient may experience erysipelas.
Grade 3a (severe edema):
· Lymphedema is present in one limb and its associated trunk quadrant.
· The difference in circumference is greater than 6 centimeters.
· Significant skin alterations, such as cornification or keratosis, cysts and/or fistulae, are present.
· Additionally the patient may experience repeated attacks of erysipelas.
Grade 3b (massive edema):
· The same symptoms as Stage 3a except that two or more extremities are affected.
Grade 4 (gigantic edema):
· Also known as elephantiasis.
· In this stage of lymphedema, the affected extremities are huge due to almost complete blockage of the lymph channels.
· Elephantiasis may also affect the head and face.
Diagnosis, assessment and monitoring
The diagnosis or early detection of lymphedema is difficult. The first signs may be subjective observations such as "my arm feels heavy" or "I have difficulty these days getting rings on and off my fingers". These may be symptomatic of early stage of lymphedema, where accumulation of lymph is mild and not detectable by any difference in arm volume or circumference.
As lymphedema develops further, then definitive diagnosis is commonly based upon an objective measurement of difference between the affected or at-risk limb to the opposite unaffected limb (e.g. in volume or circumference).
Unfortunately, there is no generally accepted world-wide criterion of difference definitively diagnostic although a volume of difference of 200 ml between limbs or a 4 cm (at a single measurement site or set intervals along the limb) is often used.
Recently, the technique of bioimpedance measurement (a method that measures the amount of fluid in a limb) has been shown to have greater sensitivity than these existing methods and holds promise as a simple diagnostic and screening tool. Impedance analyzers specifically designed for this purpose are now commercially available.
Similarly, assessment and monitoring of lymphedema progression, or its response to treatment, is usually based on the changes in volume, circumference, or impedance over time.
Stage II - Pitting may or may not occur as tissue fibrosis develops. Limb elevation alone rarely reduces tissue swelling.
Stage III - A severe increase in swelling may develop, along with skin changes, such as thickening of the skin, fat deposits, and warty over-growths. This stage of lymphedema may also be called lymphostatic elephantitis.