Leber ‘s congenital amaurosis is a hereditary disorder of the function of the retina of the eye. A special pigment epithelium located on the retina is primarily affected by the impairment. The term disease derives from the Greek word ‘amauros’, which means something like blind or dark. Leber’s congenital amaurosis is congenital and also includes various degenerative disorders that develop on the choroid of the eye.
What is Leber’s congenital amaurosis?
If typical symptoms of Leber’s congenital amaurosis appear, a suitable specialist should be consulted as soon as possible. In the case of affected children in particular, it is important not to wait to see a doctor. See AbbreviationFinder for abbreviations related to Leber Congenital Amaurosis.
Basically, Leber’s congenital amaurosis is a hereditary disease. The disorder was first described in 1869 by the doctor Theodor von Leber. He also found that the disease occurs more frequently in closely related people and in this way discovered the genetic component of Leber’s congenital amaurosis.
It is characteristic of the disease that the patients are born with visual impairments. In some cases, they are even completely blind from birth. In siblings, Leber’s congenital amaurosis also occurs with a probability of about 25 percent.
In principle, about 10 percent of all cases of blindness are caused by Leber’s congenital amaurosis. Care must be taken not to confuse Leber’s congenital amaurosis with what is known as Leber’s hereditary optic atrophy. It is a genetic disease that usually affects the optic nerve.
In principle, the term Leber’s congenital amaurosis summarizes a large number of so-called retinal -choroidal dystrophies. These arise because the affected patients have a disorder of the pigment epithelium in the retina. As a result, the retina loses its function. In addition, the choroid of the eye degenerates. The number of sick people in Germany is estimated at around 2,000.
The causes of Leber’s congenital amaurosis have now been largely clarified. The disease is genetic and is passed on to offspring in the majority of cases by an autosomal recessive route. Much less frequently, Leber’s congenital amaurosis is inherited in an autosomal dominant manner.
According to the current state of knowledge in medical research, the exact causes of the disease lie in various types of mutations. 15 subcategories of mutations and genetic defects were identified. There are often homozygosities of certain genes, which lead to the expression of Leber’s congenital amaurosis.
A potential cause, for example, is a defect in the RPE65 gene. As a result, a special enzyme is changed, which is very important for the reconstruction of the substance rhodopsin. In addition, it has been shown that Leber’s congenital amaurosis occurs more frequently in children from marriages between relatives.
Symptoms, Ailments and Signs
Leber’s congenital amaurosis is usually associated with various symptoms. On the one hand, the visual acuity of the affected patients is usually significantly reduced and the field of vision is considerably limited. In the majority of cases this leads to complete blindness. In addition, those affected often suffer from nystagmus in connection with what is known as strabismus.
There is also a low sensitivity to glare and hyperopia. In the later course of Leber’s congenital amaurosis, clouding of the lens and keratoglobe sometimes develop. In numerous cases, the findings on the retina are not very noticeable at the beginning of the disease.
However, the impairments on the pigment epithelium become more and more obvious over time. In the course of this, there is also depigmentation, which is reminiscent of salt or pepper in imaging processes. The optic nerve may be affected by atrophy.
Diagnosis and course of the disease
If typical symptoms of Leber’s congenital amaurosis appear, a suitable specialist should be consulted as soon as possible. In the case of affected children in particular, it is important not to wait to see a doctor. Because the earlier the therapy is started in young patients, the more favorable the course of the disease usually develops.
First and foremost is the anamnesis, which the treating doctor carries out together with the patient concerned. The individual complaints, the medical history of the person and family connections are the focus of the analysis. In this way, the doctor already receives a range of important information that will help him in making the diagnosis.
Finally, the typical clinical appearance indicates the presence of Leber’s congenital amaurosis. The disease can be reliably diagnosed with the help of electroretinography. If a person suffers from Leber’s congenital amaurosis, the absence of stimuli will show up relatively early on in this examination. In this way, the disease can also be differentiated from other hereditary atrophies of the optic nerves.
When should you go to the doctor?
Leber’s congenital amaurosis is hereditary and is therefore usually diagnosed immediately after birth. Whether further visits to the doctor are necessary depends on the type and severity of the disease. If the child suffers from visual problems, an ophthalmologist must be consulted in any case. In the case of severe symptoms, medical advice must be sought immediately, because if left untreated, the patient can become completely blind. People who themselves suffer from Leber’s congenital amaurosis should have a genetic test carried out when offspring are due.
With an early diagnosis, preferably in the womb, treatment can be initiated quickly. This greatly improves the child’s chances of recovery. If further visual disturbances or other problems in the area of the retina and pupils occur during treatment, medical advice is required. Other contacts are the ophthalmologist, an internist and a specialist clinic for hereditary diseases. Children should also be closely monitored by a pediatrician. Appropriate measures can then be taken quickly in the event of complications.
Treatment & Therapy
For a long time, medicine was of the opinion that Leber’s congenital amaurosis was incurable. Recently, however, studies have provided new indications of ways to successfully treat the disease. Adenoviruses are injected into the retina so that defective genes are exchanged.
Outlook & Forecast
The prognosis of the disease depends on the extent of the existing disorders. Researchers determined that the cause of Leber’s congenital amaurosis stems from a genetic defect. The challenge is therefore to find a suitable treatment method.
Due to legal requirements, doctors are not allowed to change human genetics. Nevertheless, in recent years it has been shown that for some patients, under certain conditions, there is a prospect of alleviation of the symptoms. According to initial studies, adenovians were successfully injected into the retina of the diseased patients. Vision was restored. This can significantly improve the patient’s quality of life. In some cases it has been documented that full recovery of vision has occurred and is comparable to that of a healthy human. However, this procedure is not used for every patient or does not always lead to a successful therapy. Further studies are necessary and ultimately the legal applicability will be examined.
It must be taken into account that if the therapy is unsuccessful, the risk of subsequent disorders is increased due to the emotional stress. If the course of the disease is unfavorable, it leads to the development of a mental disorder. This also reduces the patient’s quality of life and has a significant impact on the further course of the disease.
Leber’s congenital amaurosis is a hereditary disease that is present at birth. Because of this, there is no way to prevent the disease. Appropriate therapy is therefore particularly important.
In most cases, the patient with this disease has only a few follow-up measures available, since the disease cannot be completely cured and usually leads to complete blindness of the patient. Therefore, most of those affected by this disease are dependent on the help of other people and their own families in order to be able to master everyday life.
Since this is a genetic disease, it is advisable for those affected to have a genetic examination and counseling if they wish to have children in order to prevent the disease from reoccurring. The sooner a doctor is consulted, the better the further course of this disease.
If blindness has already occurred in the children, they are dependent on intensive support in their lives so that they can continue to develop normally. Loving conversations with the parents also have a positive effect on the further course and can prevent psychological problems or even depression. Furthermore, no special aftercare measures are necessary or possible. As a rule, this disease does not reduce the life expectancy of the person affected.
You can do that yourself
Patients with Leber’s congenital amaurosis are affected by the disease in their independence and quality of life. The typical limitations of the visual function lead to various problems in everyday life and sometimes result in further physical and mental suffering. Due to the reduced vision, it is possible, for example, that some patients neglect sporting activities and their fitness suffers accordingly. With regard to psychological complaints, anxiety disorders or depression come into question, since the impending blindness is an enormous burden for many people.
Regular visits to the ophthalmologist are important, so that it recognizes relevant changes in the state of the visual function at an early stage. If there are signs that the patient will actually go blind soon, he will redesign his home to accommodate the visual impairment. The aim of the new facility is to make orientation easier for the blind and to reduce the risk of accidents. In a school for the blind, blind patients practice using a cane and, if necessary, learn Braille. Most of those affected also benefit from social contacts through which they receive support despite the illness. This includes blind people. Patients often experience an increase in quality of life through dealing with other visually impaired people.