Vitamin A palmitate supplements may be useful to slow worsening. A visual prosthesis may be an option in certain people with severe disease.Currently there is only one FDA-approved gene therapy that is commercially available to RP patients with Leber congenital amaurosis type 2. It replaces the miscoded RPE65 protein that is produced within the retinal pigmented epithelium. It has been found to effectively work in about 50% of the patients who receive the therapy. The earlier the child receives the RPE65 therapy the better the chances for a positive outcome. There are many other therapies being researched at this time with the goal of being approved in the next few years. It is estimated to affect 1 in 4,000 people. Signs and symptoms
The initial retinal degenerative symptoms of retinitis pigmentosa are characterized by decreased night vision (nyctalopia) and the loss of the mid-peripheral visual field. The rod photoreceptor cells, which are responsible for low-light vision and are orientated mainly in the retinal periphery, are the retinal processes affected first during non-syndromic (without other conditions) forms of this disease. Visual decline progresses relatively quickly to the far peripheral field, eventually extending into the central visual field as tunnel vision increases. Visual acuity and color vision can become compromised due to accompanying loss of the cone photoreceptor cells, which are responsible for color vision, visual acuity, and sight in the central visual field. The progression of disease occurs in both eyes in a similar but not identical pattern.
Alports syndrome is associated with RP and an abnormal glomerular-basement membrane leading to nephrotic syndrome. It is inherited as X-linked dominant. RP combined with ophthalmoplegia, dysphagia, ataxia, and cardiac conduction defects is seen in the mitochondrial DNA disorder Kearns–Sayre syndrome (also known as Ragged Red Fiber Myopathy)
RP combined with retardation, peripheral neuropathy, acanthotic (spiked) RBCs, ataxia, steatorrhea, and absence of VLDL is seen in abetalipoproteinemia. RP is seen clinically in association with several other rare genetic disorders (including muscular dystrophy and chronic granulomatous disease) as part of McLeod syndrome. This is an X-linked recessive phenotype characterized by a complete absence of XK cell surface proteins, and therefore markedly reduced expression of all Kell red blood cell antigens. For transfusion purposes, these patients are considered completely incompatible with all normal and K0/K0 donors. RP associated with hypogonadism, and developmental delay with an autosomal recessive inheritance pattern is seen with Bardet–Biedl syndromeOther conditions include neurosyphilis, toxoplasmosis and Refsums disease. Genetics
Retinitis pigmentosa (RP) is one of the most common forms of inherited retinal degeneration.There are multiple genes that code for proteins needed in the visual pathway, when mutated, they can cause the retinitis pigmentosa phenotype. Inheritance patterns of RP have been identified as autosomal dominant, autosomal recessive, X-linked, and maternally (mitochondrially) acquired, and are dependent on the specific RP gene mutations present in the parental generation.