What is Retinitis Pigmentosa (RP)?
Retinitis pigmentosa (reh·tuh·nai·tuhs pig·muhn·tow·suh), also known as RP, is a group of inherited retinal diseases (IRDs) that affect how we see. RP affects the retina, which is in the back of the eye. The retina captures images and sends them to the brain to help us see. In people with RP, the cells of the retina that allow us to see images, called photoreceptors, slowly die off causing vision loss.
How much and fast RP progresses differs from person to person. Many people living with RP lose their vision slowly over decades, typically starting with the peripheral vision. RP affects about 80,000–110,000 people in the United States.
Healthy Eye
Eye with Retinitis Pigmentosa
What causes RP?
RP is a genetic condition. This means that there is a gene that is not working properly causing someone to have a health problem such as RP. It’s important to identify the specific gene causing your RP because over 79 genes have been found to cause retinitis pigmentosa. Different mutations can affect the retina in various ways. Genetic information about your RP is very helpful because it provides important details to your eye doctor for managing the disease and providing information to your family.
What are Genes?
Cells are the basic building blocks of all living things.
The command center of each cell is called the nucleus, and it contains chromosomes.
Chromosomes are made up of DNA—the body’s hereditary material.
A gene is a small section of DNA that contains the instructions for a specific molecule in the body, which is passed from parent to child.
Each gene contains the information required to build specific proteins needed in the body, for example, proteins build bones, determine eye color, allow muscles to move, control digestion, and keep your heart beating.
If there is a change in a gene’s DNA sequence, it is called a variant. Not all variants cause disease. A disease-causing variant is called a mutation.
Symptoms will vary depending on your age, stage of the disease, and genetic cause of disease. Some people encounter different speeds of vision loss, while others may keep their central vision longer than others.
Involve your family members in your RP journey. This will help them understand what is happening to you when your RP progresses. Your vision loss can limit important day-today activities, such as reading, driving, playing sports, and household chores. Having a reliable and strong support system and finding resources can help you keep your quality of life.
How is RP diagnosed?
RP may take longer to diagnose than other, more commonly occurring vision conditions. The diagnosis typically starts with an eye examination with an eye doctor (an optometrist or ophthalmologist). If the eye doctor thinks that you have an IRD, such as RP, they will ask you to see a retina specialist or an eye doctor more experienced in diagnosing and treating IRDs. The retina specialist will conduct further testing to confirm your diagnosis. They will conduct a very detailed examination including the steps listed below.
Initial and follow-up examinations
Initial and follow-up exams may include the following:
Patient history: The doctor will ask about your current vision issues, medical history, and medication use.
Family history: This will include putting together a family medical history to show genetic relationships and medical disorders that occur in your family. The family medical history can help the healthcare team understand the diagnosis and estimate who else in your family may have a chance for developing RP.
Clinical eye examination
Imaging
Genetic testing: You may meet with a genetic counselor (someone that specializes in the genetic testing process and educating patients) to determine the testing approach that is best based on the other test results. People living with RP are often asked to provide a blood or saliva sample that will be sent to a lab for analysis. The genetic test confirms or disputes the diagnosis of a specific IRD, so that correct information is provided to the patient and family. Genetic testing is often a requirement for participation in IRD-related clinical research trials
Once the diagnosis is established, in addition to providing any relevant medical management, the doctor may:
- Connect you to supportive services such as a genetic counselor (someone that specializes in the genetic testing process and educating people living with RP) and vision rehabilitation
- Help your family members understand their risk for the disease
- Provide information to you about clinical trials and new therapies in development
Why is Genetic Testing Important?
Identifying the genetic cause of disease is an important part of care for patients with Inherited Retinal Diseases (IRDs). Many times, the exact type of IRD a person has can be difficult to determine based only on tests conducted in the eye doctor’s office.
Results from genetic testing can lead to a more accurate diagnosis if a genetic cause of disease is identified.
A health care provider will order the genetic test, collect the sample, and review the results with the patient. Ideally, the health care team would include a genetic counselor to guide the patient and their family through the results of the genetic testing, discuss the impact on other family members, and assist couples who have questions around family planning decisions. It is often necessary to have genetic testing done if you are interested in joining a clinical trial, or if it has been several years since your last genetic test was completed.
What is the treatment for RP?
There are currently no FDA-approved treatments for RP. There is one exception for a rare type of RP caused by the RPE65 gene that can be treated by gene therapy. However, there are several clinical trials in process that may lead to treatment options. Continue to see your eye doctor every 1-2 years or as recommended. It is important to check your eyes regularly as other eye health conditions can occur. If at any time you feel there has been a change in your vision, you should see an eye doctor and have a dilated eye examination. It is also important to have a current record of an eye exam if you would like to join a clinical trial.
Those with RP usually develop cataracts at younger age than other people do who do not have RP. A cataract is a haziness or opacification of the natural lens in the eye, and may be treated with cataract surgery.
People with RP are also more likely to develop swelling or edema in the retina (cystoid macular edema), which can be treated with an eye drop or possibly an oral pill to decrease the swelling.
How can I manage my RP?
There are steps you can take now to protect your eyes and slow vision loss:
- Find vision rehabilitation providers who can help you and your family in finding ways and resources to navigate daily life with greater independence
- Wear a hat and sunglasses to protect your eyes from sunlight when you go outside
- Find a supportive community where you can connect with other people who are living with RP
- Consider talking to a mental health professional, who can help you process this diagnosis and find ways to keep you engaged in your goals
- Get protective eyewear when playing sports or working in or around potentially dangerous conditions. This includes work in manufacturing, construction, landscaping, auto repair, plumbing, woodworking, agriculture, mining, metal fabrication and health care
- Ask your eye doctor about participating in a clinical trial
- Do not smoke and avoid secondhand smoke exposure
- Try to incorporate green leafy vegetables, fish or fish oil, and antioxidant rich foods into your diet
“Being diagnosed with RP in my early 30’s was a devastating blow. But getting connected with the valuable resources available has allowed me to not only advocate for myself, but guide others to do the same. Now I realize that this diagnosis has provided me so many opportunities, connections, and blessings that I might otherwise have not experienced.”
– Brenda N. Certified ADA coordinator, and individual living with RP
