Retinal Pigment Degeneration: Characteristics
The characteristics of retinitis pigmentosa include a group of diseases of genetic origin, which manifest themselves in different ways. They lead to a gradual loss of vision, which is slow in some cases and fast in others.
There are many hallmarks of retinitis pigmentosa as it is a complex disease. In fact, it is not one disease, but a group of hereditary, degenerative and progressive diseases.
Estimates indicate that it affects one in four thousand. people around the world. However, this number varies by region.
It is an extremely rare disease. So far, only the mutations responsible for half of the cases have been identified. This is despite the fact that pigmentary retinopathy (as it is also called) was first described by Donders in 1885, that is, more than a hundred years ago.
The characteristics of retinitis pigmentosa are complex. It’s a disease that science has yet to fully describe. Currently, we believe that its development is genetic, but may also depend on various environmental factors. However, conclusive research results are still missing.
Retinitis pigmentosa: main features
Retinitis pigmentosa is a group of genetic disorders that affect the ability of the retina to respond to light. It usually affects both eyes and leads to gradual loss of vision and, in some cases, even blindness.
The retina is the lining of the inner part of the eye. Its function is to receive and process images in order to be sent to the brain via the optic nerve.
In retinitis pigmentosa, some cells of the retina turn out to be useless. In general, pigments are also accumulated at the back of the eye.
Most often, this type of disease appears between the ages of 25 and 40. However, symptoms have been reported as early as before the age of 20 and before puberty, although they appear extremely rarely. They can also happen after the age of 50.
The reasons
The cause of this disease is essentially genetic, that is, hereditary. The problem almost always comes from the existence of one or two defective genes. In other cases, the genetic mutation occurs in people with no family history of the disease.
There are basically four types of retinitis pigmentosa:
- Autosomal dominant pattern (ADRP). This is where the disease occurs in one of the parents and one of the children. It is responsible for 6 to 15% of cases.
- Autosomal recession pattern (ARRP). Then the parent does not get sick, but transfers the disease to one of his children. The deterioration begins at an advanced age. This type is responsible for 22-26% of cases.
- Conjugated X pattern (XLRP). Here the mother does not get sick, but passes it on to one of her sons. This model is responsible for 1 to 10% of cases.
- Simple pattern. Finally, the simple formula includes cases where there is no family history of the disease or parental transmission patterns. It is responsible for 50% of cases.
We now suspect that environmental factors are also involved in the onset of this disease. Some scientists also suggest that the consumption of lutein, antioxidant vitamins and Omega 3 slows the progression of this disease. In contrast, consumption of tobacco, alcohol, sun exposure and stress appear to accelerate this process.
Other facts
The first symptom of the disease is usually difficulty seeing in poor lighting conditions and at night. Gradually, the patient also loses the peripheral vision ability, which results in tunnel vision. In other words, people with this condition can only see what is in front of them.
Worsening usually occurs slowly but gradually. It often takes many years from the appearance of the first symptoms to the diagnosis of retinitis pigmentosa. It should also be remembered that the disease does not affect all people equally, even if they come from the same family.
At the moment, there is no cure for retinitis pigmentosa, but research to find one is ongoing. Scientists believe that there are currently about two million people in the world suffering from this disease. Estimates also show that one in 80 people carry the defective genes that cause it.
A person diagnosed with this condition will need psychological support to deal with the possibility of complete blindness. Virtually anyone can lead an independent life blind if he is properly prepared physically and mentally.
