Retinopathies associated with antiretinal antibodies

Clinical, electrophysiologic and serologic evidence of cancer associated retinopathy preceding a diagnosis of breast cancer

We report the case of a woman in her 50s who presented headaches, blurred vision, diplopia and loss of peripheral vision. She was treated for normal tension glaucoma based on optic nerve cupping prior to the development of diplopia. Records demonstrated visual field constriction over 4 months despite well-controlled intraocular pressures. Examination revealed decreased visual acuity and visual field constriction. The multifocal electroretinogram was abnormal. After a thorough review of her medical and family history, a concern for cancer-associated retinopathy developed. Blood samples were positive for antiretinal antibodies against 23 kDA and 46 kDA proteins. Cancer screening was recommended as the aetiology for retinopathy was unknown and revealed a left breast lump. Following lumpectomy with adjuvant chemoradiation, her visual acuity normalised and visual field defects completely resolved. This case serves to provide an example that distant systemic symptoms may be a manifestation of the underlying malignancy and the importance of clinical suspicion with prompt evaluation.

Electrodiagnostic Biomarkers in Paraneoplastic Retinopathy

OBJECTIVE

Paraneoplastic retinopathy (PNR) is a rapid-onset photoreceptor and post-photoreceptor dysfunction triggered by a cross-reaction between antigens expressed by the underlying tumour and retinal proteins. The present study aims to determine the electrodiagnostic biomarkers that support the diagnosis of PNR and evaluate the effect of treatment.

METHODS

A retrospective observational case-controlled study including 25 patients with suspected PNR, of which 11 patients were diagnosed with PNR. The presence of PNR was confirmed based on clinical examination, supported by colour fundus photography, fundus autofluorescence imaging, optical coherence tomography, fluorescein angiography, retinal vessel oximetry, colour test, full-field electroretinogram (ffERG), on-/off ERG, S-cone ERG, and multifocal ERG (mfERG). The relationships between the clinical symptomatology and the effect of therapy were evaluated.

RESULTS

All PNR patients (Nr: 11) presented with subjective symptoms of newly reported central vision or visual field deterioration. Posterior segment findings showed a severe patchy-like retinal atrophy, attenuation of the retinal vessels, and a waxy optic disc. Optical coherence tomography revealed a discontinued ISe line, and multiple hyperreflective foci. Retinal vessel oxygen saturation was increased. Multifocal ERG revealed reduced central and paracentral responses and ffERG severely attenuated scotopic-, photopic-, on-/off- and S-cone responses. The colour vision test revealed a tritan-tetartan-weakness. Two of the PNR patients underwent rituximab therapy with no further progression and even recovery of electrodiagnostic responses.In 1 nPNR (non-paraneoplastic retinopathy) patient (total Nr: 14) pseudoxanthoma elasticum-related retinopathy was the reason for impaired vision. In 3 of 13 patients with bronchopulmonary cancer a MEK- and FGFR-inhibitor- drug toxicity was the reason for the visual deterioration.

CONCLUSION

Careful investigation for signs of central and/or peripheral visual field deterioration must be performed in the presence of history of a co-existing malignancy. The possibility of PNR should be taken into account. The electrodiagnostic biomarkers, suggested in this study, may help to promptly recognise PNR and also to evaluate the effect of implemented therapy.

Structural and Functional Changes in Non-Paraneoplastic Autoimmune Retinopathy

BACKGROUND

To describe longitudinal changes in patients with non-paraneoplastic autoimmune retinopathy (npAIR) by utilizing different diagnostic modalities/tests.

METHODS

The index study is a retrospective longitudinal review of sixteen eyes of eight patients from a tertiary care eye hospital diagnosed with npAIR. Multiple diagnostic modalities such as wide-angle fundus photography (WAFP), WA fundus autofluorescence (WAFAF), spectral-domain optical coherence tomography (SD-OCT), Goldmann visual field (GVF) perimetry, microperimetry (MP), electrophysiologic testing, and adaptive optics scanning laser ophthalmoscopy (AOSLO) were reviewed and analyzed.

RESULTS

At the baseline visits, anomalies were detected by multimodal diagnostic tests on all patients. Subjects were followed up for a median duration of 11.5 [3.0-18.7] months. Structural changes at the baseline were detected in 14 of 16 (87.5%) eyes on WAFP and WAFAF and 13 of 16 (81.2%) eyes on SD-OCT. Eight of the ten (80%) eyes that underwent AOSLO imaging depicted structural changes. Functional changes were detected in 14 of 16 (87.5%) eyes on GVF, 15 of 16 (93.7%) eyes on MP, and 11 of 16 (68.7%) eyes on full-field electroretinogram (ff-ERG). Multifocal electroretinogram (mf-ERG) and visual evoked potential (VEP) tests were performed in 14 eyes, of which 12 (85.7%) and 14 (100%) of the eyes demonstrated functional abnormalities, respectively, at baseline. Compared to all the other structural diagnostic tools, AOSLO had a better ability to demonstrate deterioration in retinal microstructures occurring at follow-ups. Functional deterioration at follow-up was detected on GVF in 8 of 10 (80%) eyes, mf-ERG in 4 of 8 (50%) eyes, and MP in 7 of 16 (43.7%) eyes. The ff-ERG and VEP were stable in the majority of cases at follow-up.

CONCLUSIONS

The utilization of multimodal imaging/tests in the diagnosing and monitoring of npAIR patients can aid in identifying anomalous changes over time. Analysis of both the anatomical and functional aspects by these devices can be supportive of detecting the changes early in such patients. AOSLO shows promise as it enables the capture of high-resolution images demonstrating quantifiable changes to retinal microstructure.

Comparison of Clinical and Immunological Features of Para- and Non-Paraneoplastic Autoimmune Retinopathy in Chinese - A Series of 48 Cases

PURPOSE

To characterize and compare clinical and immunological features of para(p)-autoimmune retinopathy (AIR) and non-para(np)-AIR and to assess the clinical significance of the presence of serum anti-retinal antibodies (ARAs).

METHODS

We retrospectively reviewed 48 Chinese patients with p-AIR or np-AIR who took comprehensive ophthalmic examinations and lab tests of the presence of serum ARAs.

RESULTS

p-AIR patients differed from np-AIR patients in terms of disease progression, ocular inflammation, findings of OCT, FFA, and presence of ARAs. No significant difference was found in the band number of serum ARAs between AIR patients and healthy controls. The prevalence of antibodies to recoverin and ɑ-enolase in the sera of p-AIR was significantly higher than that of the healthy individuals.

CONCLUSION

While having many similar clinical signs, patients with p-AIR or np-AIR nevertheless displayed unique characteristics. Detection of ARAs subtypes, rather than their quantity, may be helpful in evaluating the conditions in the verified instances.

An update on autoimmune retinopathy

Autoimmune retinopathy (AIR) refers to a group of rare autoimmune retinal degenerative diseases presumably caused by cross-reactivity of serum autoantibodies against retinal antigens. The pathogenesis of AIR remains largely presumptive and there are a significant number of antiretinal antibodies that have been detected in association with AIR. The diagnosis of AIR is largely based on the demonstration of antiretinal antibodies in the serum along with suggestive clinical features and ancillary investigations. A high index of suspicion along with early diagnosis and treatment may play a critical role to lower the risk of irreversible immunological damage to the retinal cells in these patients. A multi-disciplinary approach for complete management and evaluation is helpful in such conditions. Various therapeutic options have been described for the treatment of AIR, though there is no consensus on standard treatment protocol.

Anti-Retinal Antibodies in Vitamin A Deficiency

Vitamin A is an important component of the visual cycle, and its deficiency causes a retinal degeneration that may be reversed with retinol supplementation. Here, the authors present a patient with vitamin A deficiency and rod-mediated retinopathy who was found to have multiple anti-retinal antibodies that gradually dissipated after vitamin A supplementation. This interesting case suggests the possibility that the photoreceptor degeneration induced by vitamin A deficiency may lead to transient immune exposure to retinal antigens and development of anti-retinal antibodies. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:723-726.].

Autoimmune diseases affecting skin melanocytes in dogs, cats and horses: vitiligo and the uveodermatological syndrome: a comprehensive review

Autoimmune dermatoses targeting melanocytes have gained attention in human medicine due to their progressive nature and the social impact suffered by affected individuals. In veterinary medicine, vitiligo and the uveodermatological syndrome are the two autoimmune diseases that are known to affect skin melanocytes.In the first part of this article, we will review the signalment, clinical signs, histopathology and the treatment outcome of vitiligo in dogs, cats and horses; where pertinent, we compare the animal diseases to their human homologue. In a similar fashion, the information on the uveodermatological syndrome in dogs is reviewed and, where relevant, it is compared to the Vogt-Koyanagi-Harada (VKH) syndrome in humans.Canine, feline and equine vitiligo have many features that mirror their human counterparts. The most effective treatment and outcome of vitiligo in animals remain unclear. The canine uveodermatological syndrome resembles the incomplete VKH variant in humans; for affected individuals, an immediate diagnosis and aggressive treatment are crucial to prevent the development of blindness.

The effect of autoimmune retinopathy on retinal vessel oxygen saturation

PURPOSE

To study the retinal vessel oxygen saturation alterations in patients with autoimmune retinopathy (AIR) and patients with autoimmune retinopathy associated with retinitis pigmentosa (AIR-RP) in comparison with healthy controls and patients with isolated retinitis pigmentosa (RP).

DESIGN

Prospective, cross-sectional, and non-interventional study.

SUBJECTS

Retinal vessel oximetry (RO) was performed on a total of 139 eyes: six eyes suffering from AIR and four eyes with AIR-RP were compared to 59 healthy control eyes and to 70 eyes with RP.

METHODS

A computer-based program of the retinal vessel analyser unit (IMEDOS Systems UG, Jena, Germany) was used to evaluate retinal vessel oxygen saturation. The mean oxygen saturation in the first and second branch retinal arterioles (A-SO₂) and venules (V-SO₂) were measured and their difference (A-V SO₂) was calculated. In addition, we measured the diameter of the retinal arterioles (D-A) and venules (D-V).

MAIN OUTCOME MEASURES

Oxygen metabolism is altered in patients with isolated AIR and AIR-RP.

RESULTS

Both, AIR and AIR-RP groups, differed from healthy controls showing significantly higher V-SO₂ values and significantly lower A-V SO₂ values (p < 0.025). In addition, the AIR-RP group could be differentiated from eyes suffering from isolated RP by means of significantly higher V-SO₂ values. Comparing retinal vessel diameters, both, the AIR and AIR-RP groups, presented with significant arterial (p = 0.05) and venular (p < 0.03) vessel attenuation than the healthy control group.

CONCLUSIONS

Based on our results, in analogy to patients suffering from RP, oxygen metabolism seems to be altered in AIR patients.

Autoimmune Retinopathy: Current Concepts and Practices (An American Ophthalmological Society Thesis)

PURPOSE

To elicit and evaluate opinions in the diagnosis and management of nonparaneoplastic autoimmune retinopathy (npAIR) among members of the American Uveitis Society (AUS) and to further the development of consensus and criteria in the diagnosis and management of npAIR. We hypothesize that despite lack of any clear guidelines, a general consensus in the clinical diagnosis and treatment of npAIR exists among uveitis experts.

METHODS

A literature review was performed and a panel of uveitis experts was consulted to formulate a survey regarding the diagnosis and management of npAIR. An online survey of 10 questions was developed, and a link was distributed through the AUS membership discussion list. We defined "general consensus" as meaning that a majority (>50%) of the respondents provided the same answer to a question.

RESULTS

Fifty-four members of the AUS responded to the survey. Thirty-eight members (70.4%) see one to three AIR patients per year. Greater than 50% consensus was reached on most items, particularly items relating to diagnostic features and tests (up to 96% consensus).

CONCLUSIONS

The diagnosis and management of npAIR is challenging, as standardized clinical and laboratory diagnostic criteria have yet to be established. The results of this study support the presence of consensus regarding certain aspects of npAIR, but also indicate the need for developing clear clinical diagnostic criteria and treatment guidelines.

B Cell Anomalies in Autoimmune Retinopathy (AIR)

Purpose

Autoimmune retinopathy (AIR) is a retinopathy associated with unexplained vision loss presumably linked to circulating antiretinal antibodies; currently, however, there are no standardized criteria regarding the diagnosis, treatment strategy, or pathogenesis of this disease. The importance of B-lymphocyte immunophenotyping in the classification of AIR is unknown.

Methods

We utilized 15-color multiparametric flow cytometry to identify aberrations in B cell subsets that may contribute to the pathophysiology of AIR. Luminex cytokine analysis was also performed on plasma samples from AIR patients.

Results

Significant differences in AIR patients compared to individuals with other inflammatory conditions or healthy donors were found in the B cell memory compartment, including an increase in naïve B cells and a decrease in switched and unswitched memory B cells, which correlated with alterations in immunoglobulin secretion.

Conclusions

These findings suggest that the maturation process of B cells may be impaired and that B cell immunophenotyping may help in understanding disease process in AIR.

Remission of nonparaneoplastic autoimmune retinopathy after minimal steroid treatment

PURPOSE

To describe the clinical findings in a patient demonstrating recovery from nonparaneoplastic autoimmune retinopathy after a minimal course of steroid treatment.

METHODS

Clinical presentation was documented, and paraclinical tests were obtained using Humphrey automated perimetry for visual fields, Western blotting for antiretinal antibodies, and electroretinography for evaluation of rod and cone function.

RESULTS

Initial presentation revealed marked visual field deficits, electroretinographic dysfunction, and the presence of α-enolase autoantibodies. After a brief course of oral corticosteroids, the patient demonstrated improvement in visual fields, disappearance of α-enolase autoantibodies, partial recovery of the cone on-response, and complete recovery of the rod response.

CONCLUSION

This case is distinguished from previous reports by the rapidity and degree of recovery, the brevity of treatment required, and the unique electroretinographic recovery pattern with concomitant disappearance of α-enolase autoantibodies. These findings suggest a pathologic role for α-enolase autoantibodies in autoimmune rod bipolar cell dysfunction. Identification of other cases exhibiting such improvements and associated autoantibody activity may expand our understanding of nonparaneoplastic autoimmune retinopathy disease pathogenesis.

Identification of α-fodrin as an autoantigen in experimental coronavirus retinopathy (ECOR)

The coronavirus, mouse hepatitis virus (MHV), JHM strain induces a biphasic disease in BALB/c mice that consists of an acute retinitis followed by progression to a chronic retinal degeneration with autoimmune reactivity. Retinal degeneration resistant CD-1 mice do not develop either the late phase or autoimmune reactivity. A mouse RPE/choroid DNA expression library was screened using sera from virus infected BALB/c mice. Two clones were identified, villin-2 protein and α-fodrin protein. α-Fodrin protein was used for further analysis and western blot reactivity was seen only in sera from virus infected BALB/c mice. CD4 T cells were shown to specifically react with MHV antigens and with α-fodrin protein. These studies clearly identified both antibody and CD4 T cell reactivities to α-fodrin in sera from virus infected, retinal degenerative susceptible BALB/c mice.

Autoimmune retinopathy

PURPOSE

To provide a detailed review of current clinical guidelines for the diagnosis, work-up and treatment of autoimmune retinopathy and to preview briefly possible future therapies.

DESIGN

Perspective based on literature review and clinical expertise.

METHODS

Interpretation of current literature, relying on the authors' clinical experience.

RESULTS

Autoimmune retinopathy is a rare immunologic disease characterized by the presence of circulating antiretinal antibodies along with electroretinographic and visual field abnormalities. An ophthalmic examination can be normal or show minimal findings. The diagnosis of autoimmune retinopathy is made difficult by diagnostic criteria that are both limited and nonstandardized. Currently, the diagnosis is made based on the demonstration of serum antiretinal antibodies and the presence of clinical manifestations (including abnormal electroretinographic findings). The mere presence of these antibodies is not diagnostic. Lack of an accepted gold standard for antiretinal antibodies detection and poor interlaboratory concordance make the diagnosis challenging. There are anecdotal reports of immunosuppressive therapy in autoimmune retinopathy; however, the response to treatment is variable, with more favorable results achieved in paraneoplastic retinopathy, particularly cancer-associated retinopathy, with a combination of chemotherapy and immunosuppression. Whether an earlier attempt to treat nonparaneoplastic autoimmune retinopathy would be more beneficial is unknown. Early treatment attempts are limited by lack of sensitive and specific assays and definitive clinical criteria.

CONCLUSIONS

Little is known about the clinical course, prognosis and treatment of autoimmune retinopathy. Additional studies should examine the specificity and pathogenicity of antiretinal antibodies and screen for biomarkers, and they should be conducted concurrently with studies seeking to identify appropriate treatment.

Hyperautofluorescent ring in autoimmune retinopathy

PURPOSE

To report the presence of a hyperautofluorescent ring and corresponding spectral-domain optical coherence tomography (SD-OCT) features seen in patients with autoimmune retinopathy.

METHODS

All eyes were evaluated by funduscopic examination, full-field electroretinography, fundus autofluorescence, and SD-OCT. Further confirmation of the diagnosis was obtained with immunoblot and immunohistochemistry testing of the patient's serum. Humphrey visual fields and microperimetry were also performed.

RESULTS

Funduscopic examination showed atrophic retinal pigment epithelium (RPE) associated with retinal artery narrowing but without pigment deposits. The scotopic and photopic full-field electroretinograms were nondetectable in three patients and showed a cone-rod pattern of dysfunction in one patient. Fundus autofluorescence revealed a hyperautofluorescent ring in the parafoveal region, and the corresponding SD-OCT demonstrated loss of the photoreceptor inner segment-outer segment junction with thinning of the outer nuclear layer from the region of the hyperautofluorescent ring toward the retinal periphery. The retinal layers were generally intact within the hyperautofluorescent ring, although the inner segment-outer segment junction was disrupted, and the outer nuclear layer and photoreceptor outer segment layer were thinned.

CONCLUSION

This case series revealed the structure of the hyperautofluorescent ring in autoimmune retinopathy using SD-OCT. Fundus autofluorescence and SD-OCT may aid in the diagnosis of autoimmune retinopathy and may serve as a tool to monitor its progression.

Miscellaneous vitreous-derived IgM antibodies target numerous retinal proteins in equine recurrent uveitis

OBJECTIVE

In equine recurrent uveitis (ERU), immune reactions are directed toward known antigens like S-antigen, interphotoreceptor retinoid-binding protein, and cellular retinalaldehyde-binding protein, and anti-retinal antibodies were detected in vitreous samples. The aim of this study was the investigation of intraocular immunoglobulin M (IgM) reactivities to retinal proteome.

PROCEDURES

Retina was separated by one- and two-dimensional gel electrophoresis and blotted semidry on PVDF membranes. To identify intraocular IgM antibody responses to retinal tissue, blots were incubated with vitreous samples of ERU-diseased horses (n = 50) and healthy controls (n = 30), followed by an HRP-labeled secondary antibody specific for equine IgM. Noticeable 2D western blot signals were aligned on a 2D gel of retinal proteome, excised, and subsequently identified by tandem mass spectrometry.

RESULTS

Interestingly, frequent and very miscellaneous IgM response patterns to the retinal proteome in 68% of ERU vitreous samples were detected. Binding of IgM antibodies was localized at 17 different molecular weights. The most frequently detected signal, in 21 of the 50 samples, was located at 49 kDa. Comparing the samples interindividually between one and up to nine different signals in one sample could be observed. All healthy vitreous samples were devoid of IgM antibodies. Analysis of targeted spots with mass spectrometry led to the clear identification of 11 different proteins (corresponding to 16 different spots). One candidate could not be discovered so far.

CONCLUSION

The considerable IgM response to retinal proteins demonstrates an ongoing immune response, which might contribute to the remitting relapsing character of ERU. Novel identified target proteins point to a diverse response pattern of individual ERU cases.

Occult maculopathy

PURPOSE

To report a case of bilateral decrease in central vision with almost normal fundus examination.

METHODS

A 50-year-old white man with central visual loss followed since 2006 with detailed ophthalmologic examinations and ancillary tests, including autoimmune and antiretinal antibody analyses.

RESULTS

Virtually normal ophthalmoscopic examination, fluorescein and indocyanine green angiography, autofluorescence, red-free fundus pattern, and peripheral visual field testing. Abnormalities include reduced central macula thickness values (right and left eyes were 150 μm and 146 μm, respectively) on the spectral-domain optical coherent tomography (normal value, 200-250 μm) and decreased sensitivity of foveal eccentricities on multifocal electroretinogram. Antiretinal antibody tested positive for 27-kDa protein; and anti-optic nerve antibodies tested positive against 33-kDa, 35-kDa, and 46-kDa proteins.

CONCLUSION

A central visual deficit with a nearly normal clinical picture and no family history are indicative of poorly defined entity called occult maculopathy. The role of antiretinal antibodies is unclear.

Primary retinal pathology in multiple sclerosis as detected by optical coherence tomography

Optical coherence tomography studies in multiple sclerosis have primarily focused on evaluation of the retinal nerve fibre layer. The aetiology of retinal changes in multiple sclerosis is thought to be secondary to optic nerve demyelination. The objective of this study was to use optical coherence tomography to determine if a subset of patients with multiple sclerosis exhibit primary retinal neuronopathy, in the absence of retrograde degeneration of the retinal nerve fibre layer and to ascertain if such patients may have any distinguishing clinical characteristics. We identified 50 patients with multiple sclerosis with predominantly macular thinning (normal retinal nerve fibre-layer thickness with average macular thickness < 5th percentile), a previously undescribed optical coherence tomography defined phenotype in multiple sclerosis, and compared them with 48 patients with multiple sclerosis with normal optical coherence tomography findings, 48 patients with multiple sclerosis with abnormal optical coherence tomography findings (typical for multiple sclerosis) and 86 healthy controls. Utilizing a novel retinal segmentation protocol, we found that those with predominant macular thinning had significant thinning of both the inner and outer nuclear layers, when compared with other patients with multiple sclerosis (P < 0.001 for both), with relative sparing of the ganglion cell layer. Inner and outer nuclear layer thicknesses in patients with non-macular thinning predominant multiple sclerosis were not different from healthy controls. Segmentation analyses thereby demonstrated extensive deeper disruption of retinal architecture in this subtype than may be expected due to retrograde degeneration from either typical clinical or sub-clinical optic neuropathy. Functional corroboration of retinal dysfunction was provided through multi-focal electroretinography in a subset of such patients. These findings support the possibility of primary retinal pathology in a subset of patients with multiple sclerosis. Multiple sclerosis-severity scores were also significantly increased in patients with the macular thinning predominant phenotype, compared with those without this phenotype (n = 96, P=0.006). We have identified a unique subset of patients with multiple sclerosis in whom there appears to be disproportionate thinning of the inner and outer nuclear layers, which may be occurring as a primary process independent of optic nerve pathology. In vivo analyses of retinal layers in multiple sclerosis have not been previously performed, and structural demonstration of pathology in the deeper retinal layers, such as the outer nuclear layer, has not been previously described in multiple sclerosis. Patients with inner and outer nuclear layer pathology have more rapid disability progression and thus retinal neuronal pathology may be a harbinger of a more aggressive form of multiple sclerosis.

Melanoma-associated retinopathy: a paraneoplastic autoimmune complication

OBJECTIVES

To study 11 patients with melanoma-associated retinopathy (MAR) to clarify the reliability of various methods of diagnostic testing, to determine the underlying antigenic retinal proteins, and to study the clinical histories and types of associated melanomas.

METHODS

Clinical data were obtained from patients with melanoma who developed marked visual problems. Testing included electroretinography, kinetic visual fields, comparative studies of Western blots, and indirect immunohistologic examination to detect antiretinal antibodies, as well as proteomic studies to identify underlying antigenic retinal proteins.

RESULTS

Patients with MAR typically have rapid onset of photopsias, scotomata, and loss of central or paracentral vision. Ophthalmoscopy seldom shows significant changes early, but electroretinograms are abnormal. Results of Western blots and immunohistologic examination can show antiretinal antibodies but not always. Most patients (9 of 11) had a strong family history of autoimmune disorders. Any type of melanoma (cutaneous, choroidal, ciliary body, or choroidal nevi) may be associated with this paraneoplastic autoimmune reactivity. MAR may precede or follow the diagnosis of melanoma. Patients with MAR have the same antigenic retinal proteins that have been associated with cancer-associated retinopathy. In addition, 2 new antigenic retinal proteins, aldolase A and aldolase C, were found.

CONCLUSIONS

There was a high prevalence of positive family histories of autoimmune disease in patients with MAR. To confirm the disorder, multiple clinical and serum diagnostic techniques (Western blot or indirect immunohistologic examination) are needed. Two newly observed antigenic retinal proteins, aldolase A and aldolase C, are associated with MAR.

A case of autoimmune-related retinopathy and optic neuropathy syndrome treated by autologous nonmyeloablative hematopoietic stem cell transplantation

Autoimmune-related retinopathy and optic neuropathy (ARRON) syndrome is characterized by visual loss and often the presence of antibodies against retinal or optic nerve antigens in the absence of cancer. Limited success has been reported in treatment of ARRON syndrome with medications that suppress the immune system. In many patients, current strategies are insufficient to control the disease. A 47-year-old woman with progressive visual and hearing loss attributed to ARRON syndrome that was resistant to conventional therapies underwent autologous hematopoietic stem cell transplantation (HSCT). Clinical manifestations appeared to stabilize. This report suggests that autologous HSCT may have a therapeutic role in ARRON syndrome.

Frequency of anti-retinal antibodies in normal human serum

BACKGROUND

Anti-retinal antibodies have been described in the context of autoimmune retinopathies and are often presumed to be pathogenic or disease associated. However, full characterization of patterns of anti-retinal antibody reactivity in normal human serum has been limited. The purpose of this work was to identify the profile of anti-retinal IgG antibodies in serum used as controls in laboratory testing.

METHODS

Normal human sera used in commercial diagnostic laboratories were tested for the presence of immunoreactivity against soluble human retinal proteins using Western blot analysis of fractionated soluble human retinal proteins. Reactivity was quantified using computerized densitometry, and the level of reactivity was standardized relative to a control positive serum with known reactivity against recoverin.

RESULTS

Some anti-retinal reactivity was observed in the majority of all tested normal sera. Reactivity against one to two protein bands was observed in 33%. Reactivity against five or more distinct bands was observed in 22%. There was a tendency for serum from women to react with three or more protein bands compared with serum from men.

CONCLUSIONS

The presence of anti-retinal antibodies is observed in a majority of normal control human sera, suggesting that identification of new candidate retinal autoantigens should be cautiously interpreted and subject to rigorous testing for disease association. Additional studies will aid development of a standardized protocol for validation of potential pathogenic seroreactivity.

Autoimmune retinopathy: a review and summary

Three main forms of autoimmune retinopathy (AIR) have been identified over the last 15 years: cancer-associated retinopathy (CAR), melanoma-associated retinopathy (MAR), and nonneoplastic autoimmune retinopathy (npAIR). In this chapter, the term AIR will be used to encompass all three disorders where there is commonality to their features. Complicating the issue is that AIR can be a secondary complication of other conditions such as retinitis pigmentosa, ocular trauma, birdshot retinopathy, acute zonal occult outer retinopathy (AZOOR), or multiple evanescent white dot syndrome (MEWDS). The many forms of AIR tend to have common clinical features despite the fact that there has been no uniform set of anti-retinal antibodies circulating in these patients. Patients tend to have a wide variance of anti-retinal antibody activity often with three to six different antibodies found on immunoblots. Patients typically present with a sudden onset of photopsia, rapid visual loss, and abnormal electroretinograms (ERGs). Most patients have a panretinal degeneration without pigment deposits.

Experimental coronavirus retinopathy (ECOR): retinal degeneration susceptible mice have an augmented interferon and chemokine (CXCL9, CXCL10) response early after virus infection

Mouse hepatitis virus induces a biphasic disease in BALB/c mice that consists of an acute retinitis followed by progression to a chronic retinal degeneration with autoimmune reactivity. Retinal degeneration resistant CD-1 mice do not develop the late phase. What host factors contribute to the distinct responses to the virus are unknown. Herein, we show that IFN-α, IFN-β and IFN-γ act in concert as part of the innate immune response to the retinal infection. At day 2, high serum levels of IFN-γ, CXCL9 and CXCL10, were detected in BALB/c mice. Moreover, elevated levels of CXCL9 and CXCL10 gene expression were detected in retinal tissue. Although IFN-γ and the chemokines were detected in CD-1 mice, they were at significantly lower levels compared to BALB/c mice. These augmented innate responses observed correlated with the development of autoimmune reactivity and retinal degeneration and thus may contribute to the pathogenic processes.

Cancer-associated retinopathy (CAR) with electronegative ERG: a case report

Cancer-associated retinopathy (CAR) should be suspected in patients who present with visual symptoms such as rapid unexplained visual loss and seeing shimmering lights, with an abnormal ERG. Electronegative ERG responses are not exclusive to melanoma-associated retinopathy (MAR) but may be seen in CAR as well. We describe a patient with CAR who presented with an electronegative ERG. A 67-year old woman, who presented with complaints of seeing shimmering lights, underwent an extensive ophthalmological and electrophysiological examination. Best-corrected visual acuity was 7/10 in the right and 9/10 in the left eye. Goldmann visual fields showed relative central scotomata and concentric narrowing. Slit-lamp and fundus examination were normal as was fluorescein angiography. Rod-specific ERG responses were severely reduced, with electronegative maximal combined rod-cone responses and delayed cone-responses with normal amplitudes. Melanoma-associated retinopathy was suspected. Extensive dermatological and internal evaluation eventually revealed an oat-cell carcinoma in the right lung. The patient died of pneumonia 2 years after presentation.

Cancer-associated retinopathy in patients with breast carcinoma

Introduction:

Cancer-associated retinopathy (CAR) is a paraneoplastic neurological syndrome resulting in progressive loss of vision and clinical signs of retinal degeneration. It is associated with various types of cancer and is also considered to be an autoimmune disorder that involves cross-reaction between autoantibodies and retinal proteins. The aim of this study was to establish whether immunoreactivity to retinal antigens (RAs) observed in patients with breast cancer is accompanied by any visual impairments.

Materials and Methods:

Sera of 295 patients with diagnosed breast cancer were screened for the presence of anti-RAs antibodies using immunoblotting. Cellular immunoreactivity to RAs present in retinal extracts and to purified recoverin and arrestin was determined by means of a lymphocyte proliferation assay. Six patients with high-titer antibodies to RAs then underwent ophthalmic and neurological examinations.

Results:

Four serum samples contained high-titer antibodies to a 46-kDa protein, most probably retinal α-enolase, three had antibodies to a 48-kDa protein identified as retinal arrestin, while 56-, 43-, 41-, and 34-kDa antigens were recognized only by one serum sample each. Moreover, weak cellular response to all the RAs tested was observed in one patient and another patient responded only to retinal extract. Two of the examined patients displayed symptoms of CAR.

Conclusions:

Immunoreactivity to RAs in patients with breast cancer may also be present in cases without clinical signs of CAR.

RETINAL AUTOANTIBODIES

Retinal autoantibodies, commonly referred to as antiretinal antibodies (ARA), have been implicated in the pathogenicity of a variety of immune-mediated visual disorders. In the paraneoplastic syndrome, cancer-associated retinopathy (CAR), ARA with their targeted retinal antigens have been identified. There are many other infectious, inflammatory as well as degenerative retinopathies associated with the presence of ARA. More than 15 ARA have been identified in CAR. For these autoantibodies, the autoantigens still remain unknown. Recoverin, a calcium-binding retinal protein involved in the reversal of the phototransduction cascade, is well established as the most common CAR autoantigen. The proposed mechanism of antibody-mediated degeneration involves molecular mimicry and loss of peripheral tolerance to residing retinal antigens. In vitro, ARA have been shown to cause apoptotic death of photoreceptors. Questions remain though, regarding the access and penetration of these antibodies into the retina. Furthermore, the titer of ARA does not always correlate with clinical disease status. There exists lack of standardization of antibody and antigen detection. Thus, results from different laboratories cannot exactly be compared. Sensitivity and specificity for the detection of pathogenic ARA is also lacking. Though there are many caveats, presence of ARA still serves as an adjunctive study for the clinician to confirm a diagnosis, which often is difficult to make. The study of ARA serves as an excellent model for the elucidation of pathological mechanisms underlying autoimmune retinopathy and its allied disorders.

Cancer associated retinopathy (CAR): An autoimmune-mediated paraneoplastic syndrome

Cancer associated retinopathy (CAR) is an uncommon paraneoplastic retinopathy in which antibodies are directed against retinal antigens. Vision loss is associated with abnormal ERG findings. Few case reports and lack of controlled clinical trials make management of this syndrome especially challenging for the clinician. Herein, we describe the clinical, histopathologic and electrophysiologic features of CAR, along with a summary of previously employed management options. Cancer associated retinopathy syndrome has been recognized as a paraneoplastic disorder, most commonly associated with small cell lung cancer, in which cross-reacting autoantibodies against retinal antigen cause retinal dysfunction. Bilateral vision loss as a result of both rod and cone dysfunction in CAR may occur over a period of months, and visual symptoms may precede diagnosis of the systemic malignancy. The heterogeneity in antigens that have been identified as targets of antibody-mediated retinal damage perhaps help to explain the complexity of symptoms and the treatment challenges posed by patients with CAR.

Autoantibodies to p75/LEDGF, a cell survival factor, found in patients with atypical retinal degeneration

We have identified a group of patients with an atypical retinal degeneration having anti-retinal autoantibodies in their sera. This select population is characterized by a progressively severe loss of vision associated with a decrease in photoreceptor function, abnormal pigmentation of the retinal pigment epithelium and a negative family history of retinal dystrophy. Immunohistochemical analysis on mouse retinal tissues with sera from this group of patients demonstrated high titers of anti-retinal antibodies (320 to 1,280). Anti-retinal reactivity at these levels was not detected in sera from normal individuals, or from patients with uveitis or known genetic retinal degenerations. One antigen that was identified from a retina cDNA library with sera from a patient with atypical retinal degeneration was lens epithelium-derived growth factor (LEDGF). Western blot analysis revealed that sera from all three patients demonstrated reactivity to p75/LEDGF, a survival factor that protects cells from oxidative, thermal and UV damage. In conclusion, we have found a novel group of patients with a retinal degeneration of non-paraneoplastic, non-familial origin demonstrating immunoreactivity to an autoantigen, p75/LEDGF, heretofore not associated with this disease. Finally, identification of specific anti-retinal antibodies may have applications in the diagnosis and management of retinal degeneration.

Retinal antigens are recognized by antibodies present in sera of patients with multiple sclerosis

Multiple sclerosis (MS) is frequently accompanied by visual symptoms including those related to retinal disorders. Since they may be a consequence of an autoimmune reaction, we examined whether sera of patients with diagnosed MS and changes in visual-evoked potentials contain antibodies against retinal antigens (retAgs). Immunoblot analysis revealed that MS sera recognized mainly a 46-kD antigen, a 41-kD antigen, retinal arrestin, to a smaller extent also 70-, 56-, 43-, and 36-kD proteins. Patients whose sera showed the highest reactivity with 41- and 46-kD antigens had deficiencies in visual acuity, visual fields, ophthalmoscopy, and electroretinograms. Our observation suggests that antibodies to these retAgs may play a role in the origin of ophthalmologic impairment in MS.