Autoimmune Eye Conditions
Autoimmune Retinopathy (AIR)
Autoimmune retinopathy (AIR) is a general classification of a group of rare autoimmune retinal degenerative diseases presumably caused by antibodies directly attacking the retina of the eye. AIR includes non-paraneoplastic (non-cancer) retinopathy as well as paraneoplastic retinopathy (both cancer-associated and melanoma-associated); however, since paraneoplastic retinopathies have specific terminology, this section will focus on non-neoplastic retinopathy and paraneoplastic retinopathies will be discussed below.
AIR leads to destruction of the cones (detect light and responsible for color vision and acuity) and/or rods (provide night and peripheral vision) of the retina leading to visual changes. Patients with AIR typically experience bilateral (but often asymmetric) subacute vision loss, scotomas (blind spots), photopsia (eye flashes), and nyctalopia (inability to see in dim light or at night) in the absence of intraocular inflammatory cells. In the early stages of the disease, visual acuity is typically preserved and diagnostic assessment of AIR is challenging and often delayed given its rarity and variety of clinical manifestations, including an unrevealing examination in many of the early states. Typically, patients have a personal or family history of autoimmune conditions.
Acute Zonal Occult Outer Retinopathy (AZOOR)
Acute Zonal Occult Outer Retinopathy (AZOOR) is a rare inflammatory condition and is thought to be a subtype of white dot syndrome. It is characterized by acute loss of one or more zones of the outer retinal function; however in some patients the onset can be more subacute or even chronic. The underlying cause of AZOOR is currently unknown but has been proposed to be an autoimmune condition that may possibly be triggered by a viral infection.
AZOOR causes disruption of photoreceptors in specific zones (layers) of the retina. Patients with AZOOR typically experience a sudden onset of a scotoma (blind spot) or blurred vision, often accompanied by photopsias (flashing or shimmering lights) in a localized area of the eye. Often only one eye is affected although some may experience this in both eyes as the disease progresses. Early in the disease, visual acuity is minimally affected. Young women, typically in their 30s, who are myoptic (nearsighted) are the most likely to experience AZOOR.
Birdshot Retinochoroidopathy
Birdshot retinochoroidopathy (BCR), which is also known as birdshot chorioretinopathy, vitiliginous chorioretinitis, or simply birdshot uveitis, is thought to be a rare subtype of uveitis. It is characterized by a chronic, bilateral, posterior inflammation of the uvea (middle portion of the eye) with characteristic yellow-white lesions (referred to as birdshot lesions) in the back surface of the eye. Issues with the central retina including macular edema (the macula is responsible for detailed vision), frequently occur. There is a strong genetic risk factor (the specific gene is HLA-A29) and is primarily seen in Caucasians. BCR is hypothesized to be due to a autoimmune response; however, the exact mechanism is not known.
Initially, persons with BCR experience only mild symptoms which may delay diagnosis. Those with BCR often experience a gradual decline in visual acuity over time as well as floaters, flashes, blurry or hazy vision, and changes in either color and/or night vision. In most cases, BCR is clinically distinct from other autoimmune eye conditions. Early diagnosis and treatment can help preserve vision. Without treatment, significant vision loss may occur due to irreversible damage to the retina and macula.
Multiple Evanescent White Dot Syndrome (MEWDS)
Multiple Evanescent White Dot Syndrome (MEWDS) is a rare, typically unilateral inflammatory disease that may occur after a viral illness. MEWDS affects the retinal pigment epithelium and a characteristic finding is small, white dots on the retina in a wreath-like distribution around the macula. MEWDS is four times more common in women especially those who are myopic (nearsighted) and often occur in young otherwise healthy females between the ages of 15 and 50 years old.
Patients with MEWDS often experience a sudden decrease in vision in one eye, paracentral scotoma (blind spot) and shimmering photospias (eye floaters or flashes). MEWDS is frequently self-limiting with visual recovery within 10 weeks; however, a chronic form with multiple recurrences can occur. Diagnosis is clinical and no treatment is recommended since it typically resolves with time; however, when MEWDS is suspected other potential causes of visual changes should be ruled out.
Paraneoplastic Retinopathy
Paraneoplastic retinopathy is a subtype of autoimmune retinopathy (AIR) and includes both cancer-associated (CAR) and melanoma-associated retinopathy (MAR). In CAR, the visual symptoms are often present prior to the diagnosis of cancer; whereas, in MAR, the diagnosis of melanoma is often present prior to the visual symptoms. In both cases, it is proposed that the immune system producing antibodies to fight the cancer, but these antibodies can then attack the retina. Paraneoplastic retinopathy tends to occur equally in men and women and occurs usually in the 5th or 6th decade of life.
Patients with paraneoplastic retinopathy usually present bilaterally, over the course of weeks to months. Patients typically complain of flashes of light, severely reduced visual acuity, color impairment, photosensitivity, central or peripheral ring scotomas (blind spots) and nyctalopia (inability to see in dim light or at night). MAR often has more mild visual acuity changes and color impairments compared with CAR. While no effective treatment for CAR or MAR exists, long-term immunosuppression remains the mainstay of therapy. Treatment of the underlying malignancy typically does not improve vision and overall, the visual prognosis is poor.
Punctuate Inner Choroidopathy (PIC)
Punctuate Inner Choroidopathy (PIC) is a rare inflammatory disorder that affects the vascular layer, or choroid, of the eye. It is characterized by the presence of multiple, small, well-defined, yellow-white fundus lesions, in the absence of intraocular inflammation. The underlying cause is not fully understood, but PIC is proposed to be an autoimmune condition. It occurs most common in young, near-sighted (myopic) women.
Persons with PIC may have varying symptoms and severity but often include scotomata (blind spots), blurred vision, photopsias (flashes of light), floaters, photophobia (light sensitivity), distorted vision and/or peripheral vision loss. Some cases are self-limiting and resolve on their own; however, severe vision loss may occur as a result of inflammation and growth of new blood vessels (neovascularization) and scarring. Treatment is recommended whenever neovascularization is present. Visual prognosis for many with PIC is favorable, but if scarring or neovascularization occurs severe vision loss can occur.
Retinal Vasculitis
Retinal vaculitis is an inflammatory eye condition that involves the retinal blood vessels. Typically, retinal vasculitis would occur as a part of an ocular or systemic inflammatory disease; however, it can be an isolated condition albeit this is relatively rare. It is associated with various infective, auto-immune, inflammatory or neoplastic disorders. Although there is a large diversity among the potential causes, the clinical presentation of inflammatory changes are similar. Retinal vasculitis is characterized by exudates around retinal blood vessels resulting in white-yellow material surrounding the affected blood vessels. In a smaller subset of patients with retinal vasculitis, there can be an occlusion of blood flow through the retinal vessels (occlusive vasculitis).
Detection of retinal vasculitis is made clinically, and confirmed with the help of fundus fluorescein angiography (imaging of the blood vessels of the eye). The management of retinal vasculitis depends on the underlying etiology. Adequate control of the intraocular inflammation is essential for achieving remission of retinal vasculitis. This disease can be recurrent and aggressive in its course and may require immunosuppressive therapy. Those with occlusive vasculitis have a poorer visual prognosis with a higher number of complications.
Uveitis
Uveitis is inflammation inside the eye, specifically affecting one or more of the three parts of the eye that make up the uvea. The type of uveitis is determined by the part or parts of the eye that are inflamed. Anterior uveitis or iritis affects the inside of the front of your eye and is the most common type of uveitis. Intermediate uveitis affects the retina and blood vessels just behind the lens as well as the gel in the center of the eye. Posterior uveitis affects a layer on the inside o the back of the eye, either the retina or choroid. Panuveitis occurs when all layers of the uvea are inflamed. It can affect one or both eyes and is most prevalent in people ages 20 to 50. Although multiple different things can cause uveitis, frequent causes are infection, injury, or an autoimmune or inflammatory disease.
Diagnosis typically occurs during a dilated eye exam and further diagnostic tests are utilized to help determine the likely cause. Uveitis warning signs often come on suddenly and may worsen quickly. Common signs and symptoms of uveitis include eye redness with or without eye pain, photophobia (light sensitivity), blurred vision, floaters, and decreased vision. For non-infectious causes of uveitis, the most common treatment approach is steroids either as eye drops, oral pills, eye injections or eye implants. For some persons, other immunosuppressive treatment may be utilized.