About RETINITIS PIGMENTOSA
Retinitis Pigmentosa (RP) is a rare genetic disorder characterized by progressive vision loss from dying cells in the retina.
RP is the most common disease group in the inherited retinal disease (IRD) family and is also known as rod dystrophy or rod-cone dystrophy.
Genetic variants found in more than 60 genes can cause various types of RP.
PREVALENCE / ONSET
The prevalence of RP is 1 in 3,000 to 1 in 5,000 worldwide.
Symptoms of RP are usually present from childhood. Since there are many types of RP, the severity and rate of worsening of symptoms vary from person to person
RP is diagnosed based on tests using an ophthalmoscope, electroretinogram, and visual field test. Then, the type of RP is confirmed with genetic tests.
As gene-phenotype correlations continue to be revealed through research and novel therapies continue to be developed, the importance of molecular diagnosis is growing.
With a special drop to widen your pupil, the doctor can look into your eye. If there are dark spots on your retina, there are possibilities of having RP.
Using a special contact lens or a film of gold foil, the doctor can measure how your retina responds to light.
Visual Field Test
With a tabletop machine that shows objects or lights on the side of the vision, it can create a map of your visual sight.
By using genetic tests, causal genes can be detected and selected to give an accurate diagnosis. Accurate diagnosis is necessary to give an accurate treatment.
In a UK research study, 135 common pathogenic variants were found in 4,326 patients with IRD, and a list of 20 most frequently shared genes between the patients was released. 12 of them - RPGR, PRH2, RP1, RHO, CRB1, PRPF31, RPE65, EYS, GUCY2D, PROM1, RDH12 - have been found in previous research literature to be closely associated with RP.
Because there are many genes that can cause eye disease, the American Academy of Ophthalmology recommends genetic testing for accurate diagnosis and appropriate treatment. However, the majority of clinical ophthalmologists are not familiar with diagnosis through genetic testing.
Since there are more than 60 different RP types, three different inheritance patterns are possible depending on the type; X-linked, autosomal recessive, and autosomal dominant.
- RP, in general, is currently incurable. However, there are available treatments that aim to treat certain diseases in the RP group or slow the progression of disease.
Voretigene neparvovec-rzyl (Luxturna)
Voretigene neparvovec-rzyl (Luxturna) produced and marketed by Novartis and Roche is an adeno-associated virus vector-based gene therapy where intact RPE65 gene that can replace mutated autosomal recessive RPE65 gene is injected into a patient’s body. This only covers one gene of many other RP causing genes; however, this is a new possibility that could lead to many other RP treatments.
Second Sight’s Argus 2s Retinal Prosthesis System
Second Sight’s Argus 2s Retinal Prosthesis System is also an option for patients severely impacted by RP.
Special glasses (or sunglasses)
A light amber filter can be added to eyeglasses and help improve tolerance of bright lights.
Some research suggests that high dosages of vitamin A can help slow the disease's progression in some people. Based on recent findings, vitamin A palmitate is recommended to RP patients.
Helpful communities for RETINITIS PIGMENTOSA
- WebMD. What Is Retinitis Pigmentosa?
- NIH. Retinitis pigmentosa
- ORPHANET. Orphanet: Retinitis pigmentosa
- Columbia University Department of Ophthalmology. Retinitis Pigmentosa
- Novartis. Inherited Retinal Disease | LUXTURNA
- MedlinePlus. Retinitis Pigmentosa: MedlinePlus Genetics
- Second Sight. Argus II: the life-changing retinitis pigmentosa treatment.
- Pontikos N, et al. Genetic basis of inherited retinal disease in a molecularly characterized cohort of more than 3000 families from the United Kingdom. Ophthalmology. 2020;127(10):1384-1394.
- Lam BL, et al. Genetic testing and diagnosis of inherited retinal diseases. Orphanet Journal of Rare Diseases. 2021;16(1).
- Centerwatch. Retinitis Pigmentosa Research Trials
- Foundation Fighting Blindness. Research