FORT LAUDERDALE, Fla. — Autoimmune retinopathy is a rare disease that is difficult to diagnose because of the near absence of clinical findings, symptom overlap with those of other diseases and limited, nonstandardized diagnostic criteria.
“AIR is a diagnosis of exclusion,” Lucia Sobrin, MD, MPH, said at Retina World Congress.
Autoimmune retinopathy is a rare disease that is difficult to diagnose because of the near absence of clinical findings, symptom overlap with those of other diseases and limited, nonstandardized diagnostic criteria.
Autoimmune retinopathy (AIR) is classified as paraneoplastic — either cancer associated or melanoma associated — or non-paraneoplastic.
“With the cancer-associated tag, we think that there is some cross-reactivity between tumor antigens and retinal proteins. But in non-paraneoplastic, we don’t really know if it’s regressed malignancy or some infection that initiates the new process,” Sobrin said.
Testing for retinal antibodies does not provide a reliable answer, she said. Of the many antiretinal antibodies reported in the literature, the only one that has strong, consistent pathogenicity in AIR is recoverin.
“Most antibodies don’t have good pathogenicity associated with them. And in fact, if we tested the serum of everyone in this room, 93% of us would have at least one antiretinal antibody, so it’s not a specific test, and the testing in different laboratories often doesn’t agree. So, the take-home point here is that just because a patient has positive antiretinal antibodies, it doesn’t mean they have AIR,” Sobrin said.
When patients present with a variety of visual symptoms, including vision loss and visual field alterations, and the exam is normal, suspicion for AIR should arise, particularly if OCT shows some outer retinal loss. Electroretinogram (ERG) will be the next step, followed by fundus autofluorescence (FAF), fluorescein angiography and indocyanine green angiography.
“In a patient with visual symptoms and a depressed ERG, the things I think about ruling out are retinal toxicity from medications, particularly in cancer patients who are getting chemotherapy, vitamin A deficiency, IRDs and occult posterior uveitis,” Sobrin said.
One FAF finding recently reported in patients with AIR is a circular perivascular autofluorescence pattern that expands as the disease evolves. This sign was found in about a quarter of AIR patients and may be a clue to the diagnosis, she said.
Specific testing will be performed to rule out vitamin A deficiency and syphilis. In addition, genetic testing should be performed to rule out an inherited retinal degeneration (IRD).
“If it is positive, it is helpful. You’ve confirmed the diagnosis; they avoid unnecessary treatment. But if it’s negative, it’s important to remember that the patient could still have an IRD of an as-yet unknown genetic mutation. I tell patients that, even if we proceed with treatment, we may still be dealing with an IRD,” Sobrin said.
It is also important to rule out occult malignancy in these patients because many of them may not have had a cancer diagnosis at the time they present with eye symptoms. Sobrin prescribes a PET-CT scan, skull base to pelvis, and a visit to the dermatologist and full exams, making sure that all other routine cancer screenings have been regularly performed.
The treatment approaches most commonly used are immunosuppression, intravenous immunoglobulin (IVIG) and rituximab. In a study of 16 patients by Davoudi and colleagues, 77% of eyes achieved stable or improved vision after treatment with rituximab, but 23% got worse despite treatment. In another study conducted by Sobrin and co-authors, nine patients treated with IVIG were compared with a natural history cohort of 12. All patients treated with IVIG achieved improved or stable vision, while 67% of the nontreated patients had significant visual acuity decline. ERG analysis also showed significantly less decline with treatment.
References:
- Cox JT, et al. Ophthalmol Retina. 2024;doi:10.1016/j.oret.2024.02.011.
- Davoudi S, et al. Am J Ophthalmol. 2017;doi:10.1016/j.ajo.2017.04.019.
Sources/Disclosures
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Sobrin L. Insights into diagnosis and treatment of autoimmune retinopathy. Presented at: Retina World Congress; May 9-12, 2024; Fort Lauderdale, Florida.
Disclosures:
Sobrin reports no relevant financial disclosures.