Autoimmune Retinopathy: Overview and More

Autoimmune retinopathy (AIR) is a term used to describe various rare autoimmune conditions that attack the retina of the eye. The retina is a thin nerve layer that lines the back of the eye and plays a crucial role in a person’s ability to see. The retina senses light and converts it to neural impulses, which are sent through the optic nerve straight to the brain. Damage to the retina can lead to significant visual disturbances and even vision loss over time.

This article reviews the different types of AIR, symptoms, methods of diagnosis, and treatment options.

Types of Autoimmune Retinopathy

Autoimmune retinopathy occurs when the body’s own antigens are recognized as foreign antigens, somewhat like unwanted invaders. This triggers a complex response from the immune system, ultimately leading to destruction of the retina.

There are two main categories of AIR:

• Nonparaneoplastic autoimmune retinopathy (npAIR), the most common form of AIR
• Paraneoplastic autoimmune retinopathy (pAIR), also referred to as cancer-associated retinopathy (CAR)
  

The exact cause of autoimmune retinopathy remains largely unknown, and research is still being actively conducted to better understand this category of diseases.

Based on the type of AIR, various antigens and antibodies are involved, and symptoms and treatment vary widely.

Nonparaneoplastic AIR

Symptoms of npAIR

While it still remains unknown what definitively causes npAIR, it has been found that individuals with this form of AIR typically are younger in age compared to those with CAR, and have a strong personal or family history of inflammatory autoimmune disease.

Symptoms of npAIR include, but are not limited to:

• Subacute vision loss
• Eye floaters or flashes
• Blind spots
• Decreased color vision

Diagnosis of npAIR

Excluding any form of cancer is critical when diagnosing npAIR.

The presence of specific antibodies may also help differentiate npAIR from CAR. While there is some overlap, anti-recoverin, anti-carbonic anhydrase II, anti-α-enolase, and anti-rod transducin-α antibodies have all been associated with npAIR diagnosis. The presence of these antibodies alone is not sufficient for diagnosis, however.

It’s also important to note that symptoms of npAIR may precede an eventual cancer diagnosis, so healthcare providers should remain vigilant in monitoring for any cancer development.

Additionally, a thorough series of eye tests should be performed by an ophthalmologist, including:

• Visual field testing
• Color vision tests
• Fundus auto-fluorescence imaging
• Full field electroretinogram
• Optical coherence tomography
  

Treatment of npAIR

There is no standard treatment protocol for AIR, but there are commonly used agents to help manage the disease.

The typical first-line treatment for npAIR is the use of corticosteroids. Since combination treatment is usually needed, antimetabolites or medications which interfere with cell synthesis, such as Imuran (azathioprine) or the immunosuppressant cyclosporine, can be used.

The goal of all treatment is to halt the progression of the disease, preserving as much vision as possible. Regaining vision which has already been lost from either npAIR or CAR is highly unlikely.

In npAIR, if there is an underlying systemic inflammatory illness present, that condition must be well-controlled to help slow the progression of AIR.

Paraneoplastic AIR

The most common cancer associated with pAIR, also referred to as CAR, is small cell lung cancer, followed by cervical and endometrial cancers, and uterine sarcomas.

Symptoms of pAIR/CAR

Women are twice as likely as men to develop CAR, and onset is usually after the age of 45.

CAR is associated with both rod and cone dysfunction, the cells associated with light/dark and color perception, respectively.

CAR symptoms may develop prior to or after the diagnosis of cancer. Symptoms of CAR include, but are not limited to:

• Bilateral, slowly progressive vision loss
• Prolonged glare after light exposure
• Decreased color perception
• Central blindspots
• Poor night vision

Diagnosis of pAIR/CAR

Like npAIR, a thorough history and extensive ophthalmic exam is crucial for diagnosis of CAR. Other important tests include:

• Visual field testing
• Color vision tests
• Fundus auto-fluorescence imaging
• Full field electroretinogram
• Optical coherence tomography

Additionally, the most sensitive and specific antibodies associated with CAR are recoverin antibodies, which are expressed by a variety of different tumor cells. While recoverin antibodies can be found in npAIR, they tend to be more abundant in CAR.

Tubby-like protein-1, heat-shock cognate protein 70, and glyceraldehyde 3-phosphate dehyrdogenase antibodies are also associated more specifically with CAR.

Treatment of pAIR/CAR

pAIR/CAR tends to be more responsive to treatment when compared to npAIR and MAR.

Corticosteroids are the first-line therapy for all forms of AIR. Typical “triple” therapy of CAR includes steroids and the antimetabolites azathioprine and cyclosporine.

Other immunosuppressants such as mycophenolate mofetil and the biologic rituximab have also been used as successful treatment options.

Intravenous immunoglobulin (IVIG) has been used successfully in managing pAIR, but only if given before the onset of irreversible central nervous system involvement. In case studies, IVIG was found to improve both visual acuity (sharpness) and visual fields.

Summary

Autoimmune retinopathy is an umbrella term used to refer to a group of rare eye conditions affecting the retina. If left untreated, AIR can lead to permanent vision loss. While much still remains unknown about AIR, a thorough history and examination can lead to a proper diagnosis, and treatment can be tailored to each individual.

A Word From Verywell

If you or a loved one has noticed any recent changes in your vision, do not hesitate to see your healthcare provider or an eye specialist immediately. AIR is a group of progressive retinal diseases which, if left untreated, can lead to debilitating and permanent vision loss. Fortunately, if found early, treatment options can help preserve your vision.