Slowly progressive non-neoplastic autoimmune-like retinopathy

A three-year longitudinal study of retinal function and structure in patients with multiple sclerosis

BACKGROUND

Researchers have in recent years begun to investigate ophthalmological manifestations of multiple sclerosis (MS) other than optic neuritis (ON), and it is now clear that changes to retinal function (measured using the electroretinogram, ERG) and structure (measured using optical coherence tomography, OCT) are found in MS patients irrespective of prior ON episodes. ERG results are consistent with dysfunctional bipolar cells, as in other autoimmune diseases. To date, studies have presented only cross-sectional data regarding ERG and OCT. We, therefore, studied the longitudinal course of ERG and OCT in patients with MS, as well as the effect of disability changes and non-ON clinical relapses on these functional and structural measures.

METHODS

MS patients (n = 23) participating in an ongoing longitudinal observational study were invited to take part in a 3-year ophthalmological substudy. ERG and OCT were performed, and measures of MS-related disability and relapse history were obtained. Study visits were repeated annually. ERG peak times, rod b-wave amplitude, mixed rod/cone and cone b-/a-wave amplitude ratios, thickness of the peripapillary retinal nerve fibre layer, and volumes of the segmented retinal layers/complexes were analysed. Using generalised estimating equation models adjusted for age, ON, and MS treatment status, we assessed changes to ERG and OCT over the study duration, the effect of changes in disability and recent non-ON MS relapses on ERG and OCT, and the effect of selected OCT parameters on corresponding ERG parameters.

RESULTS

At the group level, small fluctuations of several ERG peak times were recorded, with OCT values remaining stable. Increased disability between visits was associated with significant prolongation of mixed rod-cone ERG b-wave peak times. No evidence of associations between OCT and ERG parameters was observed.

CONCLUSIONS

Retinal bipolar cell function may be affected by changes in disability in patients with MS; however, recent non-ON MS clinical relapses appear not to affect ERG or OCT results. As ERG changes in MS patients over 3 years are likely to be small and of uncertain clinical relevance, longitudinal studies of retinal function in MS should be planned over an extended period.

Are Anti-Retinal Autoantibodies a Cause or a Consequence of Retinal Degeneration in Autoimmune Retinopathies?

Autoantibodies (AAbs) against various retinal proteins have been associated with vision loss in paraneoplastic and non-paraneoplastic autoimmune retinopathies (AR). There are two major paraneoplastic syndromes associated anti-retinal AAbs, cancer-associated retinopathy (CAR), and melanoma-associated retinopathy. Some people without a cancer diagnosis may present symptoms of CAR and have anti-retinal AAbs. The etiology and pathogenesis of those entities are not fully understood. In this review, we provide evidence for the role of AAbs in retinal death and degeneration. Studies of epitope mapping for anti-recoverin, anti-enolase, and anti-carbonic anhydrase II revealed that although patients' AAbs may recognize the same retinal protein as normal individuals they bind to different molecular domains, which allows distinguishing between normal and diseased AAbs. Given the great diversity of anti-retinal AAbs, it is likely some antibodies have greater pathogenic potential than others. Pathogenic, but not normal antibodies penetrate the target cell, reach their specific antigen, induce apoptosis, and impact retinal pathophysiology. Photoreceptors, dying by apoptosis, induced by other than immunologic mechanisms produce substantial amounts of metabolic debris, which consequently leads to autoimmunization and enhanced permeability of the blood-retinal barrier. AAbs that were made as a part of anti-cancer response are likely to be the cause of retinal degeneration, whereas others, generated against released antigens from damaged retina, contribute to the progression of retinopathy. Altogether, AAbs may trigger retinal degeneration and may also exacerbate the degenerative process in response to the release of sequestered antigens and influence disease progression.

Retinal involvement in uveitis associated with Hodgkin disease

PURPOSE

To describe a patient with Hodgkin disease with posterior uveitis who also had a thinning of the retina and an antiretinal autoantibody in his serum.

METHODS

Our patient was a 58-year-old man who had been diagnosed with Hodgkin disease. He had a complete ophthalmologic examination including fluorescein angiography, electroretinography, perimetry, and spectral-domain optical coherence tomography. A search for antiretinal antibodies in the serum was made by Western blot analysis, and the retinal sites reactive to the antibodies were determined by immunohistochemistry.

RESULTS

The ocular signs were mild cellular infiltration in the anterior chamber and vitreous, and small, round chorioretinal lesions in the peripheral retina. The electroretinograms were slightly reduced. Small ring-like scotomas were detected in the Goldmann visual fields. An antiretina-specific 116-kDa antibody was detected in the serum by Western blot analysis, and the antibody reacted with the ganglion cell and inner nuclear layers of mice retinas. Although the visual acuities were maintained for over eight years, the macular thickness measured in the spectral-domain optical coherence tomography images was reduced.

CONCLUSION

The presence of an antiretinal autoantibody, granulomatous uveitis, and retinal thinning in a patient with Hodgkin disease suggests that the patient had a granulomatous uveitis associated with Hodgkin disease or lymphoma-associated uveitis with retinal involvement.