When a child is diagnosed with a leukodystrophy it’s a shock to parents. Leuko..what? It is something they have never heard of, there has been no family history of it and it has happened out of the blue.

But that’s the thing with rare diseases like leukodystrophies. They lay hidden in everyone’s genes for generations. Most families who have a child with a rare disease have no family history of the problem at all.

We all carry variations in our genes that can cause rare diseases and it’s just bad luck if you have one and it gets past on to your children and causes a problem. It’s no one fault, it’s not something we have done, it just happens. There are thousands of rare diseases, each disease affects about one in 5000 newborns, but when you add the thousands of these rare diseases up them all up, they affect a lot of people. In fact 8% of Australians have a rare disease.

Here is a good summary of what a rare disease is: https://www.rarevoices.org.au/page/15/what-is-a-rare-disease

Most children with leukodystrophies are well at birth, but slowly over time the parents notice things are not quite right. The parents often end up taking their child to multiple doctors and they get multiple tests but no one can find out what is wrong. Sometimes the parents are even told they are over-reacting, but the parents’ instincts are right.

Leukodystrophies normally take a while to get diagnosed because they are hard to see at the beginning, are not on anyone's radar, and the best test for them is an MRI scan. MRI scans are a big deal for kids because they need to have a general anaesthetic to make sure they don’t move during the scan, which would make the pictures blurry and unreadable.

MRI of the brain of a person with leukodystrophy

Leukodystrophies normally take a while to get diagnosed because they are hard to see at the beginning, are not on anyone's radar, and the best test for them is an MRI scan. MRI scans are a big deal for kids because they need to have a general anaesthetic to make sure they don’t move during the scan, which would make the pictures blurry and unreadable.

What happens in a leukodystrophy is that there is brain damage which gets slowly worse over time. It is called leukodystrophy or leucodsytrophy because the part of the brain called the white matter is damaged and “leuco” means white in Greek. It is the myelin, which is the insulating material for brain cells, in the white matter which is actually damaged.

What happens when the white matter part of the brain is damaged is that brain function slowly gets worse. The earliest way this shows up in a child is that they may not feed properly or they may not meet developmental milestones like being able to sit up or crawl or walk.

In leukodystrophies the underlying reason for the damage is normally genetic. One or both of the parents carry a silent variation in their genes that does not affect them but when passed on to their child results in the condition.

Hidden genetic variations in parents:, each time they have a child there is a 25% risk that a child is affected

Some of the leukodystrophies have treatment like Fabry disease or X-Linked Adrenoleukodystrophy, Krabbe disease and Metachromatic leukodystrophy. The treatment may involve injections of a medication or it may be a bone marrow transplant. Sometimes the treatment is very effective, sometimes it may only slow the brain damage. For most of the leukodystrophies there is unfortunately no treatment.

Here is a link to an easy to understand summary of some of the leukodystrophies:

https://rarediseases.org/rare-diseases/leukodystrophy

Since leukodystrophies are rare, hard to diagnose and some of them have treatment that can make a difference, babies are routinely tested for some of them at birth in countries like the USA, Taiwan and Italy but it is not done in the public system in Australia. The aim is early detection of the treatable leukodystrophies which allows treatment to be started to try and prevent damage to the brain. For most of the leukodystrophies where there is no treatment, there is no early detection test.

Genepath have developed an early detection test for 30 hidden genetic conditions in children that are treatable if found early enough, but which are not screened in the public system in Australia. The test includes screening for 5 treatable leukodystrophies.

Leukodystrophy: early detection can help