Autoimmune Retinopathy Presenting With Findings of Degenerative Retinal Diseases in Both Eyes: A Report of Two Cases

Autoimmune retinopathy (AIR), a retinopathy involving an autoimmune response, is broadly categorized into paraneoplastic AIR (pAIR), in which an immune response against a tumor attacks the retina, and nonparaneoplastic AIR (npAIR), in which no tumor is identified.Recent findings indicate that both types can be further classified into three clusters based on clinical presentation.Case 1 involved a 39-year-old woman who presented after noticing the rapid onset of visual field defects.Her initial best-corrected visual acuity (BCVA) was 1.2 in both eyes; visual field testing revealed ring scotomas bilaterally, and multimodal imaging analysis showed retinal damage corresponding to the areas of visual field loss.Blood tests ruled out conditions such as sarcoidosis and tuberculosis.Although pAIR was suspected and a systemic workup was performed, no abnormalities were detected.Following disease onset, treatments including methylprednisolone pulse therapy, sub-Tenon's injection of triamcinolone acetonide, adalimumab, and methotrexate were administered, but no improvement was observed.Disease progression was slow; her BCVA was maintained for nine months after onset, and progression of visual field constriction (ring scotomas) was mild.Testing for paraneoplastic neurological syndrome-associated antibodies yielded negative results for all markers; consequently, she was diagnosed with "possible npAIR" (Cluster C), presenting with findings resembling retinitis pigmentosa (RP).Case 2 was a 51-year-old woman who presented with abnormal genital bleeding, was diagnosed with endometrial cancer, and underwent surgery.She had begun experiencing photopsia two months before surgery and sought consultation after noticing a visual disturbance near the center of her right eye postoperatively.At the initial visit, her BCVA was 1.2 in the right eye and 1.5 in the left eye; visual field testing revealed ring scotomas in both eyes.Multimodal imaging analysis showed retinal damage corresponding to the areas of visual field loss.Testing for paraneoplastic neurological syndrome-associated antibodies was positive for anti-recoverin antibodies; she was diagnosed with "probable pAIR," specifically Cluster C, presenting with findings resembling RP.Although Cluster C is typically considered a unilateral condition, the high likelihood that AIR can manifest bilaterally suggests that bilateral Cluster C cases associated with AIR may also occur.