Leber’s Congenital Amaurosis

What is Leber’s congenital amaurosis?

Leber’s congenital amaurosis (LCA) is a rare condition that affects the retinas in babies’ eyes. Babies born with LCA have low vision — they often lose some or all of their sight. Many babies who have LCA are born blind.

LCA is a congenital condition, which means your baby is born with it. It’s caused by genetic mutations that affect how your child’s retinas develop.

The retina is the layer at the very back of your eyeball. Photoreceptors in your retinas process light into an electrical signal that your brain can understand as images you see. Rods are photoreceptors that help you see at night and in dim light. Cones process color and make up most of your usual vision.

Leber’s congenital amaurosis makes the rods and cones in your baby’s retinas malfunction. It changes how much electrical energy your child’s retinas can use and process. The less electrical activity there is, the less sight your child will have. If there’s no electrical activity in your child’s retinas, they won’t be able to see at all.

If your child has Leber’s congenital amaurosis, they’ll begin losing their sight when they’re around 6 months old. The most common treatments for LCA try to improve what vision your child does have.

Visit an eye care specialist as soon as you notice any changes in your child’s eyes or if it seems like they’re having trouble seeing.

How common is Leber’s congenital amaurosis?

Leber’s congenital amaurosis is rare. It affects around 2 out of every 100,000 babies born each year. Fewer than 50,000 people in the U.S. are living with LCA.

Even though it’s rare, LCA is one of the most common causes of blindness in children.

What are the symptoms of Leber’s congenital amaurosis?

Children with Leber’s congenital amaurosis how have low vision or no vision. Because it usually develops in babies less than a year old, it might be hard or impossible for you to know something is affecting your child’s eyes.

Your child might start rubbing their eyes a lot. This is usually the first sign that something is affecting their vision. They may seem bothered by light. You might notice your child’s eyes shaking, which is called nystagmus.

Other symptoms of Leber’s congenital amaurosis include:

• Keratoconus.
• Light sensitivity (photophobia).
• Farsightedness (hyperopia).
• Slow or missing pupillary response (your child’s pupils won’t adjust to changes in light conditions).

What causes Leber’s congenital amaurosis?

Several genetic mutations can cause Leber’s congenital amaurosis. Genetic mutations are changes to your DNA that occur in your biological parent’s reproductive cells (egg and sperm) during conception.

Mutations in almost 30 different genes can cause Leber’s congenital amaurosis. The most common genetic mutations that cause LCA happen to genes that develop and form your retina, including:

• CEP290.
• CRB1.
• GUCY2D.
• RPE65.

LCA is usually an autosomal recessive condition. This means both biological parents need to pass an altered gene onto their child for their baby to inherit the genetic condition. If both parents have one of the genetic mutations that can cause LCA, there’s a 25% chance their children will develop it.

Many people carry autosomal recessive traits but don’t know it because they don’t have any symptoms. Talk to a healthcare provider about genetic counseling if you’re worried about your risk of passing genetic conditions to your children.

How is Leber’s congenital amaurosis diagnosed?

An eye care specialist will diagnose Leber’s congenital amaurosis. They’ll perform an eye exam to look at your child’s eyes (including inside them). They’ll use electroretinography (ERG) to measure the electrical activity in your child’s retinas. Your child might need an optical coherence tomography (OCT) scan, too.

Usually, an eye care specialist will also rule out other conditions that can affect your child’s eyes. You might see this referred to as a differential diagnosis. Some conditions they’ll check for include:

• Retinitis pigmentosa.
• Joubert syndrome.
• Zellweger syndrome.
• Color blindness (achromatopsia).
• Dropping eyelids (ptosis).

How is Leber’s congenital amaurosis treated?

There’s no cure for Leber’s congenital amaurosis. An eye care specialist will treat LCA symptoms to improve any sight your child has. Treatments to support their vision usually include eyeglasses and other low vision aids like magnifying glasses or reading prisms.

Gene therapy for Leber’s congenital amaurosis

The U.S. Food and Drug Administration (FDA) approved the first gene therapy for Leber’s congenital amaurosis in 2017. Gene therapy is an experimental treatment using genetic material to treat or prevent certain diseases. It’s currently only approved to treat LCA caused by mutations to the RPE65 gene.

Gene therapy works by replacing or inactivating disease-causing genes. In some cases, gene therapy introduces new genes into your body to treat a specific disease. With gene therapy, doctors deliver a healthy copy of a gene to cells inside your body.

An eye care specialist will tell you if your child is a good candidate for gene therapy.

How can I prevent Leber’s congenital amaurosis?

You can’t prevent your child from developing Leber’s congenital amaurosis if they’ve inherited one of the genetic mutations that cause it. Talk to a provider if you’re worried about the risk of your children inheriting genetic disorders.

What can I expect if my child has Leber’s congenital amaurosis?

You should expect your child to have little to no eyesight if they have Leber’s congenital amaurosis. Most babies born with LCA lose part or all of their vision.

Your child will need regular eye exams to track any changes in their eyes. An eye care specialist will tell you how often your child will need their eyes examined.

When should I see my healthcare provider?

Visit an eye care specialist as soon as you notice any changes in your child’s eyes or if it seems like they’re having trouble seeing.

If your child has already been diagnosed with Leber’s congenital amaurosis, see an eye care specialist if it seems like their vision or other symptoms are changing or getting worse.

What questions should I ask my doctor?

• Does my child have Leber’s congenital amaurosis?
• Which mutation caused it?
• Which tests will my child need?
• How much of their vision will they lose?
• Is my child a good candidate for gene therapy?

Is there a link between Leber’s congenital amaurosis and autism spectrum disorder?

Leber’s congenital amaurosis and autism spectrum disorder are both conditions that affect a child’s development. LCA affects babies’ retinas in their eyes. Autism spectrum disorder is a type of neurodevelopmental disorder.

Some studies have found a link between children born with LCA and autism spectrum disorder. However, this doesn’t mean babies born with LCA will definitely develop autism spectrum disorder.

A note from Cleveland Clinic

Leber’s congenital amaurosis (LCA) makes cells in your child’s retinas malfunction. If your child is diagnosed with LCA, they’ll probably lose their vision.

Genetic mutations cause Leber’s congenital amaurosis. Talk to a provider about genetic counseling if you’re worried about passing any potential genetic mutations or conditions on to your children.

Being born with LCA doesn’t mean your child won’t be healthy and happy. An eye care specialist will help you understand what to expect. They’ll tell you how often your child will need follow-up eye exams and which treatments can support any vision they do have.