What is Leber Congenital Amaurosis? Dr. Shagas Explains
Are you curious about Leber Congenital Amaurosis also known as LCA? Check out this video where Dr. Shagas goes in-depth about this rare genetic disorder that is usually detected within the first 6 months of birth.
Can you describe how someone is diagnosed with LCA?
Leber Congenital Amaurosis is a type of inherited retinal dystrophy. It manifests itself in the first six months of life with significant vision loss. Patients can be diagnosed with LCA with the help of a thorough eye exam from an eye care provider. During the exam the retina is assessed.
Although initially patients who have Leber Congenital Amaurosis may have a relatively normal looking retina, the degeneration of the retina occurs later in life. During the assessment, the provider also looks for other signs, things like nystagmus, which is an involuntary or roving eye movement that can occur often. Kids with LCA, usually experience light sensitivity.
The exam alone is often not enough to diagnose LCA. A special test called an ERG or electroretinogram is needed to give the diagnosis of LCA as well as family history and genetic testing are helpful for that diagnosis.
What are some of the warning signs and symptoms that people should be aware of?
Vision loss is the primary symptom. It’s difficult to assess vision loss in infants. They can’t necessarily tell us when they’re babies, however there are some signs that parents can watch for; for instance if the child is not following objects with their eyes, if they’re unable to fix their gaze on objects, then we worry about vision loss.
Another sign to be aware of is involuntary eye movement or nystagmus, as well as sensitive to light. Some children at times feel like they need to poke or rub their eyes, as a way to try to stimulate their eyes. If parents are noticing these type of signs then they need to get in to see an eye care provider to get their child’s eyes evaluated.
Is LCA a progressive eye disease? If so, how long does it typically take for progression to occur?
LCA is a progressive eye disease. The visual acuity in children with LCA differs, some kids are born with some vision and some with no light perception. There’s a bit of variation depending on the different gene mutations. The progression of the disease is different for everybody as well.
Who is primarily diagnosed with LCA?
Infants are primarily diagnosed with LCA. Usually LCA is inherited in an autosomal recessive manner, which means that both parents must carry the defective gene for the condition to be passed on to their child. There’s a particular abnormal gene called RPE65 and with that condition, the vision loss happens a little bit later in life than in the typical LCA case.
In working with patients with LCA, in what sorts of ways does it start affecting their lives? Daily tasks? Work? Relationships?
It affects all aspects of the patient’s lives as well as the parents; as they figure out next steps, resources, and what to expect. Often children with LCA begin learning adaptive techniques early on in life, which can help them really thrive as they grow older.
When someone comes in with an LCA diagnosis, what can they expect at an appointment at our low vision clinic?
They can expect a complete functional vision assessment that will determine how they are using their vision and how to enhance and optimize the vision that they have. We often will evaluate what adaptive techniques and devices are helpful to them such as magnifier or talking devices. Also a big part of what we do, especially when we see kids in the clinic, is connect the patients and their family members to resources.
National resources, as well as local resources such as connecting them to the resources in their schools as well. That is a big part of what we do in the clinic.
How common is Leber Congenital Amaurosis?
It is a rare genetic eye disorder. The prevalence of LCA has been estimated one to two in 100,000 births. This disorder, affects males and females equally. It does account for about 20% of legal blindness in children.
Is there any new research related to Leber Congenital Amaurosis that you’re aware of? Any advances in medicine that might be coming down the line?
Yes, there are treatments in the pipeline. In 2017, the FDA did approve Spark Therapeutics to use a gene therapy called Luxturna. And that was for the RPE65 gene, the one that affects people later in their life.
Is there anything else that somebody should know about LCA, especially if it runs in their family and they’re thinking of having children?
Genetic testing plays a crucial role in obtaining an accurate diagnosis as well as planning for the future and staying on top of the latest research.
