Lymphedema

Overview: What is lymphedema?

The ancient Greek word oidema means swelling. In medicine, edema is a swelling caused by an accumulation of fluid in the tissues. Lymph is a fluid consisting of plasma, protein and white blood cells. It transports toxins and pathogens through the lymphatic channels to the lymph nodes. If the lymphatic channels are displaced, interrupted or dysfunctional, the lymph can no longer be transported away. The pressure in the lymph vessels increases. Ultimately, the lymph penetrates into the neighboring tissue or escapes from the lymph vessels. This leads to swelling of the tissue and ultimately to the development of lymphoedema.

Frequency: Lymphedema is not rare

No precise data is available on the incidence of lymphoedema in the population. imates suggest that approximately 140-250 million people worldwide suffer from lymphedema.

Causes and risk factors: genes, surgery and cancer

The causes of lymphedema are either congenital or acquired. This is referred to as primary or secondary lymphoedema.

Primary lymphedema

Primary lymphoedema, which accounts for only one to two percent of all cases, is typically associated with a malformation of the lymphatic system. In this case, there is usually a reduction in the number of lymphatic vessels or a narrowing of these, which in turn is associated with an impairment of the transport capacity of the lymph. In childhood or puberty, lymphedema is manifested by unilateral or bilateral swelling of the legs or arms. If primary lymphedema manifests itself from birth, it is called congenital lymphedema. If primary lymphedema begins between the first and 35th year of life, it is called lymphedema praecox (premature, early lymphedema). If it does not appear until after the age of 35, we refer to it as lymphedema tardum (late lymphedema). The distinction between the praecox and tardum forms is particularly important because differential diagnosis, especially at an older age, must take into account the blockage of lymphatic drainage by a malignant disease (cancer). Why can consequences of a congenital anomaly perhaps only appear in old age? It may very well be that the transport capacity and thus the function of the lymphatic vessels is restricted as a result of a malformation. However, the lymphatic vessels are still able to perform their tasks adequately in the sense of transporting the lymph away from the body. Lymphoedema only occurs when the transport capacity of the lymph vessels is no longer sufficient.

Secondary lymphedema

Secondary lymphoedema is acquired in the course of life. The following causes are possible:

• Injuries, sprains or scars
• Surgery and radiation as part of cancer treatment
• Tumors, especially malignant lymph node diseases, such as Hodgkin’s disease or leukemia
• Inflammations of the lymph nodes
• Inflammations with parasites, bacteria, fungi or viruses

Symptoms: box toes, Stemmer's sign or elephantiasis

Lymphedema is initially manifested by painless, dough-like swellings and skin retractions. These increase with heat or, in women, during menstruation. The unpleasant thing is that the skin around the water accumulation is susceptible to infection. If lymphedema is primary, it typically rises on both sides from the toes to the lower or even upper thigh. The toes deform under pressure and become square (box toes). They develop deep transverse wrinkles and their undersides become rough and warty. The skin on the back of the foot can no longer be lifted (Stemmer’s sign). In the course of the disease, typical tissue remodeling processes also occur, which lead to an increase in connective tissue (fibrosis) and hardening of the tissue (sclerosis). In the advanced stage, the entire leg can deform as a result of these tissue remodeling processes and is then referred to as elephantiasis. Primary lymphedema due to developmental disorders may be associated with various other developmental disorders. Different syndromes are described: Klippel-Trenaunay syndrome, Ullrich-Turner syndrome, Noonan syndrome, yellow nail syndrome. Secondary lymphedema is usually unilateral. Lymphedema can also affect the face, neck, trunk, and genitals. Depending on how advanced the disease is and which specific symptoms appear, we speak of the following stages of lymphoedema:

• Stage 0: Transitional phase without externally visible swelling.
• Stage 1: Soft, doughy swelling, especially visible in the evening
• Stage 2: Hard swelling with connective tissue proliferation (also called fibrosis)
• Stage 3: Elephantiasis, with bulky swelling of entire body parts and thickened skin

Diagnosis: clinical examination and microlymphography

A diagnosis of lymphedema is made by taking a medical history and performing a physical examination. In this process, we also assess the stage of the disease – an essential criterion for the selection of treatment. In addition, we will arrange for blood, ultrasound and imaging diagnostic procedures. Lymphedema is diagnosed clinically. However, concomitant diseases or an early stage often complicate the diagnosis, making additional examination necessary. One important method is fluorescence microlymphography. The University Hospital Zurich is able to offer this method due to interdisciplinary cooperation. In special cases, lymph scintigraphy is also performed.

Prevention, early detection, prognosis

Prevention of both primary and secondary lymphedema is not possible.

Course and prognosis

The course of lymphoedema depends on two important conditions:

• Timely detection and correspondingly early treatment.
• If possible, the cause of the lymphedema should be eliminated

Secondary lymphoedema up to stage 1 can regress. They generally have a better prognosis compared to primary lymphedema. The cause of secondary lymphedema and its treatment success play an important role in the course of the disease. If the cause of lymphedema can be cured, the chance that it will improve or even completely resolve is relatively high. Without treatment, the disease will progress. It hardens and leads to permanent skin changes. The skin is irritated and inflamed, vesicles, crusts and scales may form. These changes are the result of a disturbance in the metabolism of the tissue, which can even destroy layers of the skin. Thus, after a certain point, healing is no longer possible. Primary lymphedema is not completely curable. However, a significant improvement of the symptoms is possible.

Lymphedema: treatment through relief and elimination of the cause

The most important goal of therapy is to relieve the tissue by removing the congestion. In the case of secondary lymphedema, the cause must be found out and treated. In the early stages, it is advisable to elevate the affected body part as long as possible and repeatedly. Avoid tight clothing that exerts additional pressure on the tissue. Thanks to its interdisciplinary approach, the University Hospital Zurich is able to offer a broad spectrum of therapeutic procedures. This includes drug-conservative therapy up to surgical reconstruction of lymphatic vessels. In addition, an accompanying recommendation may be made to reduce risk factors.