Milroy’s Disease

What is Milroy’s disease?

Milroy’s disease is a type of primary lymphedema (an issue with lymph drainage). “Primary” means another disease doesn’t cause it. This genetic (inherited) disease is congenital (present at birth). It doesn’t allow the usual lymphatic system nodes and channels to develop fully, which makes them unable to work well. Without lymphatic drainage, lymph fluid builds up and causes swelling in a baby’s lower legs and feet.

Another name for Milroy’s disease is hereditary lymphedema type I.

The process of getting a diagnosis for Milroy’s disease can be frustrating because healthcare providers don’t see many cases of it. But if you notice swelling in your baby’s legs, it’s worth asking their provider about it. The sooner your child sees a provider, the faster they can get a diagnosis and start treatment.

How rare is Milroy’s disease?

This disease happens in about 1 in 6,000 births. It’s more common in people assigned female at birth (AFAB). For every one person assigned male at birth (AMAB) who has it, there are at least two AFAB who have it.

What are the symptoms?

Your child may have these Milroy’s disease symptoms as a newborn:

• Swelling (edema) in their lower legs (usually below both knees)
• Veins that stick out from their lower legs
• Hydrocele (fluid causing swelling in your scrotum)
• Toenails that slant up
• Papillomatosis (noncancerous growths)
• Gastrointestinal (digestive) issues

What causes Milroy’s disease?

A variant in the FLT4 gene causes Milroy’s disease. People with Milroy’s disease usually have a biological parent who has the disease. It passes to children in an autosomal dominant pattern, which means it only takes one parent to pass it on. One sibling with this disease may have more severe symptoms than the other or have symptoms at a different age.

About 9 out of 10 people with the FLT4 variant have swelling in their legs by age 3.

How is it diagnosed?

A Milroy’s disease diagnosis begins with a physical exam. It may also include tests like:

• Ultrasound (imaging) during pregnancy or after birth
• Lymphoscintigraphy (imaging)
• Genetic testing

Your child’s provider may refer you to a pediatric-certified lymphedema therapist.

How do you treat Milroy’s disease?

You can use at-home treatments to help your baby’s swelling from this disease. Milroy’s disease treatment for leg swelling includes:

• Compression therapy (socks)
• Kinesiology or KT tape (athletic tape)
• Shoes that provide support

These simple treatments work well in most cases. If not, lymphatic drainage massage can help. A provider can perform this and teach you how to perform it, as well.

If these methods don’t work, your child’s provider may recommend surgery at some point to help your child’s lymphatic system work better. This could involve:

• Removing affected tissue
• Using a bypass procedure to redirect lymphatic fluid away from areas that need better lymph drainage
• Moving working lymph nodes from elsewhere in your child’s body to their legs (a procedure known as vascularized lymph node transfer)

What can I expect if my child has this condition?

Because Milroy’s disease is rare, you may need to explain it to teachers and others in your child’s life. Talking about it can help a teacher understand why your child may take longer to change clothes for gym class or why they shouldn’t be barefoot (the risk of injury and infection). But they can still do most of the things their classmates can do.

Milroy’s disease is a chronic (long-term) condition. Leg swelling can get worse in some people and better in others. Without treatment, swelling from this disease can make the affected area feel hard. People with this condition may also develop cellulitis, an infection that can spread to your bloodstream.

How do I take care of my child?

Ways to care for your child with Milroy’s disease include:

• Take good care of your child’s skin and treat infections right away to limit issues with cellulitis.
• Try to protect them from injuring their legs because they’re more at risk of infection than others who don’t have Milroy’s disease.
• Make sure they’re moving their legs often and aren’t keeping them still for long.
• Encourage physical activity, especially swimming.
• Check with your provider before giving your child medicine to be sure it won’t make swelling worse.
• Limit how much salt they eat, as it makes their body retain fluid.
• Encourage your child to eat nutritient-dense foods so they take in enough nutrition.

When should my child see a healthcare provider?

Your child will have regular checkups with their healthcare provider for Milroy’s disease. This helps their provider see how they’re doing and find out if the disease is staying the same or getting worse. Contact your child’s provider if you feel that treatments aren’t helping and you want to try others. Your child may also see an occupational therapist to help them use their limbs better.

What questions should I ask my healthcare provider?

Questions you may want to ask your child’s provider include:

• Which of our relatives could be at risk for this disease?
• Do you know of any support groups for Milroy’s disease?
• Can you help me find a source for compression garments for my child?
• In your experience, how well will simple treatments work?