Stargardt Disease: Symptoms, Causes, Diagnosis, and Treatment

DR. AJAY SHARMA October 27, 2023

Stargardt disease is a genetic eye condition that causes central vision loss. It is a rare eye disease with no cure that usually develops in children, teenagers, and adults. Other names for the condition include Stargardt macular degeneration, fundus flavimaculatus, and ABCA4 retinopathy, which refers to the genetic mutation of the disease.

Stargardt disease causes the central part of the retina, the macula, which is crucial for central vision. The area is responsible for central vision sharpness and most of the eye’s ability to see the colors.

People with Stargardt disease rarely lose all of their central vision or any of their peripheral vision. Therapy can help people to manage their symptoms and perform their daily activities.

Symptoms

Signs and symptoms of Stargardt disease include:

• Difficulty in achieving clear and sharp vision.
• Presence of gray or black spots in the central visual field.
• Struggles with low-light or dimly lit environments for clear vision.
• Experiencing a loss of color vision.
• Experiencing uncontrolled, involuntary eye movements.
• Facing challenges in adapting to fluctuations in lighting conditions.

People with this disease may experience symptoms at different levels of severity. Eye care providers will be able to identify changes in the shapes and colors of parts of your eyes.

Causes

This disease results from changes in the ABCA4 gene, which affects how the body uses vitamin A. The ABCA4 gene generates a protein that facilitates the removal of surplus fatty substances generated during the body’s utilization of vitamin A for retinal cell formation.

However, in the case of Stargardt disease, the malfunction of the ABCA4 gene results in the inhibition of this protein production, consequently causing the accumulation of fatty materials on the retina.

Is Stargardt Disease Contagious?

No, The Stargardt disease is not contagious. It’s not something you can transmit to or contract from anyone. This genetic disease is transmitted from one generation to the next through heredity.

What are the Risk Factors?

Stargardt disease is a rare eye condition. The Macular Society in the United Kingdom states that only 1 in 10,000 people have this disease.

It is also a genetic disease; someone must inherit it from their biological parents. Usually, for symptoms to manifest, both parents must transmit the defective ABCA4 gene. However, rare forms of the disease only need one parent to pass down the gene for signs and symptoms to happen.

Genetic tests are available to determine the genes that can cause Stargardt disease. These tests can yield information about an individual’s gene carriage status, although they can occasionally produce inconclusive results.

Diagnosis

An eye care specialist will diagnose the disease by examining the fatty materials around the retina. They may also assess the extent of the vision loss through tests, including:

1. Visual Field Testing
   This assesses the range and sensitivity of the person’s vision. It also can identify blind spots.
2. Electroretinography
   This assesses the electrical signals within the retina when exposed to light. Irregular reactions to light can indicate the presence of diseases, such as Stargardt disease.
3. Optical Coherence Tomography
   This creates retinal images through the utilization of light waves.
4. Autofluorescence Imaging
   This involves a camera that measures retinal cells to check for unusual patterns.

Treatment

Stargardt disease has no cure to prevent the macula from degenerating, but it can be manageable. Clinical trials are underway to explore treatment options for this form of macular degeneration and various other variants. Scientists are investigating metformin, a medication traditionally prescribed for diabetes management, as a potential pharmaceutical intervention to decelerate the advancement of Stargardt disease. They hope that metformin will improve the health of specific cells, including retinal cells.

Other clinical trials are centered on gene replacement therapy, aiming to provide a corrected version of the ABCA4 gene to replace the flawed variant. However, ABCA4 is very large, so its size presents a problem.

Other research focuses on methods to guide embryonic stem cells into differentiating into retinal pigment epithelium, potentially offering a promising avenue for vision restoration.

How Can I Manage Symptoms of Stargardt Disease?

There are several things to manage Stargardt disease. Some of the ways are:

• Stop smoking. Avoid being around second-hand smoke.
• Wear sunglasses or a hat to reduce your sensitivity to light. This will also help you to protect your eyes from the ultraviolet rays from the sun.
• Avoid attempting to boost your vitamin A levels through supplementation. The levels you get from food or a multivitamin product are enough.
• Ask your healthcare provider regarding the possibility of joining a clinical trial.

When to See an Eye Care Provider if I have Stargardt Disease?

Your eye care specialists recommend regular check-ups to monitor your eye health. It’s crucial to maintain these appointments. Nevertheless, if you experience any changes in your vision or encounter pain and discomfort, you must contact your healthcare provider promptly.