Autoimmune Retinopathy Diagnosis And Features
Being diagnosed with Autoimmune retinopathy is the start of a potentially traumatic journey that will need lots of support. Autoimmune retinopathy (AIR) is an inflammatory mediated retinopathy characterized by vision loss, scotomas, an area of lost or depressed vision within the visual field, surrounded by an area of less depressed or of normal vision; visual field deficits, photoreceptor dysfunction and the presence of circulating anti-retinal autoantibodies (ARAs). According to Landon Grange (2013), the sine qua non of AIR is the presence of circulating ARAs, which target retinal antigens and are believed to be responsible for the photoreceptor damage, though the precise mechanisms are not entirely understood.Autoimmune Retinopathy Diagnosis And Features AIR can be studied in two groups: paraneoplastic and non-paraneoplastic (npAIR), with paraneoplastic further subdivided into cancer-associated retinopathy and melanoma-associated retinopathy. Paraneoplastic AIR was first described in 1976 and the term “paraneoplastic retinopathy” was coined by Klingele (1984). Evidence suggests that paraneoplastic AIR may be triggered by molecular mimicry between tumor antigens and retinal proteins. Similarly, npAIR may be triggered by molecular mimicry between retinal proteins and presumed viral or bacterial proteins.
Patients with npAIR typically present with subacute vision loss, scotomas, photopsias, an appearance as of sparks or flashes, in retinal irritation; nyctalopia or night blindness and dyschromatopsia; A condition in which the ability to perceive colors is not fully normal. Visual acuity can be deceivingly good in the early stages. On examination, the fundus may appear unremarkable. Common clinical features in AIR patients include retinal vascular attenuation, diffuse retinal atrophy, retinal pigment epithelial changes and waxy disc pallor. AIR is usually bilateral but it can be asymmetric. Typically there are minimal or no intraocular inflammatory cells.
As might be expected for an entity with no consensus in diagnosis, retrospective studies in patients with npAIR showed that clinical features vary considerably. In one study, diffuse retinal atrophy was seen in the majority of patients (83 percent) and pigment deposits in only a small proportion (13 percent), and macular edema was present in approximately half of the cases. In another study pigmentary changes were seen in approximately half of the patients and macular edema was present in only 24 percent. Autoimmune Retinopathy Diagnosis And Features
Because of the presumed autoimmune nature of AIR, various forms of immunomodulatory approaches have been tried. However, the ambiguity in diagnosis creates an enormous challenge in the management of AIR. Immunomodulatory therapy can be considered empiric. In a cohort of 24 non-paraneoplastic AIR patients who received therapy with various combinations of prednisone, cyclosporine, azathioprine, mycophenolate mofetil, periocular or intravitreal steroid injections, 15 of the 24 showed varying degrees of improvement in visual acuity or visual field, and CME improved in almost half of the patients. Decrease in ARAs following treatment may be seen in some cases; however clinical significance of this finding is unclear.
There is no clear cut treatment for Autoimmune Retinopathy. Majority of the treatment is focused on improving vision and other symptoms of this immune disorder. This is usually done by medications which suppress the immune system. These medications are also known as immune modulators. These medications include steroids, mycophenolate mofetil, and intravenous immunoglobulin therapy. These medications may not completely alleviate the disease but may help with the patient’s symptoms to a large degree of Autoimmune Retinopathy.Autoimmune Retinopathy Diagnosis And Features