Introduction
The disease is a chronic progressive, bilateral retinal degeneration of the carpet. It is often difficult to determine the type of inheritance. Most cases are autosomal recessive, but they can also be autosomal dominant or X-linked, while the latter are not common. The disease may also be part of certain syndromes (eg, Bassen-Kornzweig syndrome, Laurence-Moon-Biedl syndrome).
Cause
The disease is a hereditary disease. Its genetic pattern is autocrine recessive, dominant and sexually linked recessive. The autosomal recessive inheritance is the most; the dominant is second; the sexual linkage recessive inheritance is the smallest. At present, the autosomal dominant inheritance is considered to have at least two gene loci, located on the short arm of the first chromosome and the long arm of the third chromosome. The sex-linked genetics are located in the short-wall region of the X chromosome and in the second region.
Regarding the pathogenesis, in the past 20 to 30 years, there have been some clues to the valve. According to the examination data of electron microscopy, histochemistry, electrophysiology, fundus fluorescein angiography, etc., it is estimated that the occurrence of this disease is mainly due toRetinal pigmentEpithelial cells degenerate the phagocytosis and digestive function of the extracellular disk membrane, causing the disc membrane to disintegrate, and the procedure forms an obstacle, which hinders the rotation of nutrients from the choroid to the retina, thereby causing progressive malnutrition of the visual cells. And gradually denatured and disappeared. This process has been confirmed in a retina of RCS mice with primary retinal pigmentation.
As for the cause of phagocytic digestive failure of pigment epithelial cells, it is still unclear. May be associated with genetic abnormalities, the lack of certain or certain enzymes. In immunology, in recent years, studies have found that patients with this disease have abnormal humoral and cellular immunity, activated T cells, B cells and macrophages in the vitreous, and retinal pigment epithelial cells express HLA-DR antigen, but normal people do not. Performance. At the same time, it is also found that patients with this disease have autoimmune phenomena, but there is still no sufficient basis for whether the disease has autoimmune diseases. In terms of biochemistry, it is also found that patients with this disease have autoimmune phenomena, but there is still no sufficient basis for whether the disease has autoimmune diseases. In terms of biochemistry, it was found that the patients had abnormal lipid metabolism and accumulation of lipofuscin in the retina; trace elements such as zinc, copper and selenium and enzyme metabolism were also abnormal.
In summary, the disease may have a variety of different pathogenesis.
symptom
The retinal trocar is involved, resulting in night blindness and a symptom of early childhood. The mid-circumferential dark spots (found through visual field examinations) gradually expanded, resulting in a loss of vision in the final center.
The most prominent finding under ophthalmoscopy is the presence of a melanocyte-like appearance of melanin in the equator of the retina. Retinal artery stenosis, the nipple can be yellow wax color. Other clinical manifestations include degenerative vitreous opacity, cataract and myopia, which may be associated with congenital hearing loss.
Diagnosis can be by special examination (eg dark adaptation, electroretinogram). Other retinopathy similar to retinitis pigmentosa (such as those with syphilis, rubella, chloroquine poisoning) must be excluded, and the patient's family should be examined to determine their genetic pattern.
diagnosis
Identification of secondary retinitis pigmentosa after some congenital or acquired chorioretinal inflammation.
Congenital syphilis and fetal fundus lesions caused by pregnant women in the third month of pregnancy, the fundus findings after birth are almost identical to the disease, ERG, visual field and other visual function test results are also difficult to distinguish. Primary pigmentation can only be diagnosed after determining that the child's parental serum syphilis response is negative and that the mother has no history of rubella in the early pregnancy. If necessary, it will take a long time to follow-up observation. Congenital secondary pigmentary degeneration is already present at birth and the condition is still.
Acquired syphilis and certain acute infectious diseases (such as smallpox, measles, scarlet fever, mumps, etc.) can occur in chorioretinitis, and the fundus changes after inflammation subsides, sometimes similar to primary pigmentary degeneration. When the medical history, serological examination and fundus pigmentation are large, the position is deep, irregular (non-osteocyte-like), choroidal retinal atrophy, optic disc atrophy is grayish white (not waxy yellow), and night blindness is lighter. Identification.
complication
Post-polar cataract is a common complication of this disease. It usually occurs in the late stage, the crystal turbidity is star-shaped, and it is located in the inferior cortex of the posterior capsule. The progress is slow, and finally the whole crystal is turbid. About 1% to 3% of cases are complicated by glaucoma, mostly wide angle, and the angle of closure is rare. Some people have studied from a statistical point of view and believe that glaucoma is associated with the disease rather than complications. About 50% of cases are accompanied by myopia. Myopia is more common in patients with autosomal recessive and sex-linked recessive inheritance. It can also be found in other members of the family. Deaf-mute disease and the disease also reached 19.4%. Both the retina and the inner ear Corti are derived from the neuroepithelial, so the progressive degeneration of both may be from the same gene.
Pigmentation and deafness can occur not only in the same patient, but also in different members of the same family, but the two do not seem to be derived from different genes, possibly due to the multi-directionality of the same gene. The disease may be associated with other hereditary diseases, the more common one is the Laurence-Moon-Bardt-Biedl syndrome, which is caused by the pituitary region and the retina. Typical individuals have five components: retinitis pigmentosa, genital dysplasia, obesity, multiple fingers (toe) and intelligent defects. The syndrome occurs in the early stages of development and has significant clinical manifestations around the age of 10 (or earlier). The five components are not owned, and are called incomplete. In addition, the disease has a blink of an eye or other organs complicated or associated with diseases, rare.
treatment
Lack of effective treatment in slowing the course of retinal degeneration. In recent years, the fetal retinal nerve layer has been transplanted into patients, and preliminary reports have confirmed that vision can be improved.
In the literature, there are trials of vasodilators, vitamin A and B1, tissue therapy, various hormones, Chinese herbal medicines, acupuncture and other methods, or to avoid rapid deterioration of visual function.
1. The choice of blackout glasses can accelerate the appearance of extracellular nodules, so it is necessary to wear blackout glasses. In theory, the color of the lens should be red and purple in the same color as the red, but it is harmful to the gray for beauty, 0 to 1 for cloudy or indoor use, and 2 to 3 for gray or sunny. Dark black sunglasses are not suitable. Green lenses are disabled.
2, to avoid mental and physical over-stress When excessive stress, catecholamine increases in body fluids, choroidal blood vessels thus contract and in hypoxia, causing denaturation of visual cells. China's traditional Qigong (static power), with its own will, high-speed cerebral cortex and the activities of various organs of the body, such as perseverance, may be beneficial to prevent the rapid deterioration of the visual function of this disease.
The above content is for reference only, please consult the relevant physician or relevant medical institution if necessary.
prevention
The patients with recessive inheritance of this disease have early onset, serious illness, rapid development and extremely poor prognosis. At the age of 30, the visual function has been highly deficient, and it is nearly blind until the age of 50. In patients with dominant inheritance, the opposite is true, and occasionally it develops to a certain extent and then tends to be stationary, so the prognosis is relatively better than the recessive genotype. Therefore, you can wait until you are barely able to attend school and find employment. The insidious inheritance of this disease, its ancestors have a history of close relatives, and the prohibition of close relatives can reduce the incidence of this disease by about 22%. In addition, patients with recessive inheritance should try to avoid marriage with family members of the disease, and can not marry those who also suffer from this disease. In patients with dominant inheritance, the risk of developing this disease in their children is 50%.
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