Although the lymphatic vessel system is almost as important as the blood circulation, it is far less widely known. It covers the human body like a net and fulfils many important functions. It not only plays an important role in the body's own defence system, but it also transports up to four litres of lymph every day back out of the tissues.
This fluid contains dissolved substances such as blood proteins or metabolic breakdown products. If the system becomes diseased, return transport of the lymph fluid is no longer adequately ensured. The lymph pools and the affected parts of the body, usually the arms and legs, may develop enormous swelling. Elephantiasis is the most severe form of lymphoedema.
Such conditions of the lymph vessel system can either be congenital (primary lymphoedema) or the result of an operation (secondary lymphoedema). According to expert estimates, around three million people in Germany are affected by disorders of the lymphatic system.