Purpose: Our aim was to use molecular biological methods to study evidence of autoimmune disease in five patients with acute zonal occult outer retinopathy (AZOOR).
Methods: Ophthalmologic data and sera were collected from all patients, who underwent visual field (VF) examination, optical coherence tomography (OCT), and multifocal electroretinogram (mfERG) recording. Serum was prepared from each patient's blood and analyzed for antiretinal antibody activity using immunohistochemistry and Western blot analysis on mouse and human retinas. We also searched for antigen proteins using mass spectrometry.
Results: Symptoms were blurred vision in three patients and VF defects in two; all had enlargement of the Mariotte blind spot by VF testing. OCT findings in areas corresponding to the scotoma revealed disruptions of junction borders between inner and outer segment lines. mfERGs amplitudes were reduced in each corresponding scotoma area. Immunohistochemical serum staining revealed the target antigen was present in all photoreceptors of the mouse sensory retina. Western blot analysis using patient serum samples revealed some possible candidate antigens. Mass spectrometry could not determine the causative antigen; however, a list of candidates was discovered.
Conclusion: We determined that AZOOR could be an autoimmune disease. All AZOOR patients tested using molecular biological methods had antiretinal antigens.