In many children, yes. Scientists now believe that most cases of primary lymphoedema are caused by changes (variants) in genes involved in the development of the lymphatic system.
So far, researchers have identified more than 30 genes linked to primary lymphoedema. However, a genetic cause can currently be confirmed in only about one in three children who undergo genetic testing. This means that not finding a genetic variant does not rule out the diagnosis.

In children, lymphoedema is usually primary, meaning the lymphatic system did not develop normally before birth. Some lymphatic vessels may be missing, too small or not work as they should.
Although swelling most often affects the feet and legs, lymphoedema can occur almost anywhere in the body. It may affect the arms, hands, fingers, face, eyelids, neck or genital area.
In a small number of children, lymph fluid can also build up inside the body, for example around the lungs, inside the abdomen or, more rarely, around the heart.

Diagnosis usually begins with a visit to a specialist, who will ask about your child’s medical history and examine the swollen area.
One important clinical sign is Stemmer’s sign, where the skin at the base of the second toe or finger cannot be gently lifted.
To confirm the diagnosis and understand how well the lymphatic system is working, doctors may recommend: . Lymphoscintigraphy (the main test) . Lymphatic MRI in selected cases . Genetic testing when appropriate.

Several factors can increase swelling or trigger a flare-up:
. Weight gain or obesity, which places extra strain on the lymphatic system. . Skin infections, such as cellulitis or erysipelas, which can damage the lymphatic vessels and make swelling worse. . Puberty, when hormonal changes may cause lymphoedema to appear for the first time or become more noticeable. . Injuries or surgery, even minor ones in some children. . Certain medicines, including some anti-inflammatory drugs or corticosteroids, although these are much less common causes and should never be stopped without medical advice.

Because primary lymphoedema is a rare condition, your child should ideally be assessed in a specialist centre with experience in diagnosing and treating lymphatic diseases.
These centres bring together different healthcare professionals, such as doctors, physiotherapists, nurses and genetic specialists, to provide the best possible care.
Across Europe, many of these centres work together through the VASCERN network, helping families access expert advice and up-to-date treatment.

Yes, lymphoedema can change over time, but early treatment can make a big difference.
Although it is a lifelong condition, swelling can often be well controlled with compression garments, good skin care, regular physical activity and healthy lifestyle habits.
The way lymphoedema progresses varies from child to child and depends partly on its genetic cause. In a few rare conditions, such as Turner or Noonan syndrome, the swelling may even improve on its own.
Most children with lymphoedema can walk, run, play and take part in sports. In more severe cases, swelling and tissue hardening (fibrosis) may make movement more difficult, but staying physically active is one of the best ways to help the lymphatic system work efficiently.

Primary lymphoedema cannot usually be prevented because it is related to the way the lymphatic system develops before birth.
However, if there is a family history of lymphoedema, genetic counselling and assessment of other family members may help identify people who are at increased risk before symptoms appear.