Immune responsiveness to retinal S-antigen and opsin in serpiginous choroiditis and other retinal diseases

Multifocal Serpiginoid Choroiditis Due to Mycobacterium Mageritense following Laparoscopic Hysterectomy in an Immunocompetent Host

PURPOSE

To report nontubercular choroiditis, caused by Mycobacterium mageritense isolated using MALDI-TOF MS, following laparoscopic hysterectomy in an immunocompetent patient.

CASE REPORT

A 42-year-old female presented with gradual, painless diminution of vision in the right eye for six weeks. She had undergone laparoscopic hysterectomy two months back. BCVA was 2/60 OD. Clinical presentation and imaging all pointed to a diagnosis of serpiginous-like choroiditis. Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) had led to isolation of Mycobacterium mageritense. Patient was treated with systemic antibiotics. At 3 months follow up, BCVA improved to 6/60; fundus showed healed choroiditis and chorioretinal thinning.

CONCLUSION

Atypical mycobacterial infections associated with laparoscopic surgeries can rarely lead to debilitating systemic bacteremia resulting in profound visual impairment. The importance of timely diagnosis using specific and sophisticated methods such as MALDI-TOF MS as well as maintaining aseptic precautions perioperatively during major surgeries cannot be overemphasized.

The double-edged sword of inflammation in inherited retinal degenerations: Clinical and preclinical evidence for mechanistically and prognostically impactful but treatable complications

We present retrospective data from our clinical research efforts of the past several years alongside a review of past and current clinical and preclinical data independently by several investigators supporting our clinical evidence for the importance of inflammation in inherited retinal degenerations (IRDs). We show how inflammation is a complicating factor in IRDs but, if recognized and managed, also a great opportunity to mitigate disease severity immediately, improve patient prognosis and quality of life, extend the treatment windows for gene-specific and agnostic therapeutic approaches, mitigate the impact of inflammatory complications on the accurate estimate of vision changes in IRD natural history studies, improve the chances of safer outcomes following cataract surgery, and potentially reduce the likelihood of inflammatory adverse events and augment the efficacy of viral vector-based treatment approaches to IRDs. Manuscript contribution to the field. Inflammation has been suspected to be at play in IRDs since the beginning of the 1900s and became a research focus through the early 1990s but was then largely abandoned in favor of genetic-focused research. Thanks to regained cognizance, better research tools, and a more holistic approach to IRDs, the recent reappraisal of the role of inflammation in IRDs has brought back to the surface its importance. A potential confounder in natural history studies and a limiting factor in clinical trials if not accounted for, inflammation can be managed and often offers an opportunity for immediately improved prognosis and outcomes for IRD patients. We present our retrospective clinical evidence for connections with a measurable secondary autoimmune component that can develop in IRDs and contribute to vision loss but is at least in part treatable. We also present ample lines of evidence from the literature corroborating our clinical observations at the preclinical level.

Tubercular serpiginous choroiditis

Tubercular association with serpiginous choroiditis, also called ‘serpiginous-like choroiditis’ or ‘multifocal serpiginoid choroiditis’ (MSC) is reported from world over, especially from endemic countries. Though the exact mechanism is not yet clear, a direct or indirect infectious trigger by Mycobacterium tuberculosis (MTB) is believed to cause choroiditis.

The link of immune mechanisms with ocular inflammation caused by MTB is emerging, and has been supported by both experimental and human data. The molecular and histopathological findings of tubercular serpiginous-like choroiditis have been demonstrated in clinicopathological reports, as well as in animal models. Young to middle-aged healthy males are more frequently affected. The choroiditis lesions of tubercular serpiginous-like choroiditis evolve as multifocal lesions, affecting the retinal periphery as well as posterior pole. They begin as discrete lesions, and spread in a serpiginoid pattern to become confluent. Fundus imaging including autofluorescence is extremely helpful in monitoring patients for response to therapy. Its diagnosis is essentially clinical. Corroborative evidence is obtained by a positive tuberculin skin test, or a positive QuantiFERON-TB Gold (Cellestis, Carnegie, Victoria, Australia) test, and/or radiological (chest X-ray or chest CT scan) evidence of TB elsewhere in the body. Systemic corticosteroids are the mainstay of therapy to control active inflammation, while ATT helps to reduce recurrence of inflammatory attacks. Immunosuppressive agents are indicated in cases with relentless progression, paradoxical worsening, or recurrent choroiditis.

Importance of Autoimmune Responses in Progression of Retinal Degeneration Initiated by Gene Mutations

Inherited retinal diseases (IRDs) are clinically and genetically heterogeneous rare disorders associated with retinal dysfunction and death of retinal photoreceptor cells, leading to blindness. Among the most frequent and severe forms of those retinopathies is retinitis pigmentosa (RP) that affects 1:4,000 individuals worldwide. The genes that have been implicated in RP are associated with the proteins present in photoreceptor cells or retinal pigment epithelium (RPE). Asymmetric presentation or sudden progression in retinal disease suggests that a gene mutation alone might not be responsible for retinal degeneration. Immune responses could directly target the retina or be site effect of immunity as a bystander deterioration. Autoantibodies against retinal autoantigens have been found in RP, which led to a hypothesis that autoimmunity could be responsible for the progression of photoreceptor cell death initiated by a genetic mutation. The other contributory factor to retinal degeneration is inflammation that activates the innate immune mechanisms, such as complement. If autoimmune responses contribute to the progression of retinopathy, this could have an implication on treatment, such as gene replacement therapy. In this review, we provide a perspective on the current role of autoimmunity/immunity in RP pathophysiology.

Enigma of serpiginous choroiditis

Serpiginous choroiditis (SC) is an asymmetrically bilateral inflammation of the choroid that leads to loss of choriocapillaris atrophy or loss of overlying retinal pigment epithelium. Over the last few decades, SC has passed through a long evolution of nomenclature, etiologies and morphological variations. Initially diagnosed in patients with tuberculosis and syphilis, SC was predominantly considered as autoimmune process. With the advancement of molecular diagnosis, a new aspect of infectious subtypes of SC has emerged out. The terminologies such as serpiginous-like choroiditis (SLC) and multifocal serpiginoid choroiditis are now used to denote the subtypes of SC which are associated with infectious etiologies especially tuberculosis. In a country endemic for tuberculosis such as India, it is very important to differentiate between classic SC and SLC before initiating aggressive immunomodulatory therapy. Also, management of paradoxical worsening of the clinical condition with antitubercular treatment is another challenge in SLC and ophthalmologists should be aware of such situations. With advent of newer imaging modalities, monitoring the patient with choroiditis and identification of complications such as choroidal neovascular membrane have become much easier. This article aims to review the existing literature on SC with a special emphasis on management of SC and SLC.

Indocyanine Green Angiography in Serpiginous Choroidopathy

BACKGROUND

Manifestations of serpiginous choroidopathy have been well described, but very little is known about its true pathogenesis. By virtue of the enhanced imaging of the choroidal circulation, indocyanine green angiography may offer information on the causative factors of the disorder.

METHODS

Indocyanine Green (ICG) videoangiography was carried out in 17 patients with serpiginous choroidopathy. A full ophthalmological examination and intravenous fluorescein angiography were simultaneously done as well. The patients were studied at 3 different stages of the disease as follows: 1) with acute manifestations; 2) with subacute lesions; 3) in the inactive or healed state.

RESULTS

Acute Lesions: Indocyanine angiography showed active choroidal involvement in the acute stage beyond the limits delineated by corresponding fluorescein studies. Subacute Lesions: ICG angiography showed resolution of choroidal involvement in advance of clinical and fluorescein angiographic changes in some eyes. Healed Lesions: ICG angiography showed better delineation of the atrophic choroid with clearer definitions than corresponding fluorescein studies. Late staining of fibrovascular tissue within atrophic zones was similar to fluorescein findings. Two patients in the healed state showed multifocal hypofluorescence (one patient) and hyperfluorescent choroidal lesions (one patient) with no clinical or fluorescein counterparts, possibly representing occult lesions.

CONCLUSIONS

ICG angiography may be useful in understanding certain clinical features of the entity, such as a clearer documentation of the extent and nature of the choroidal damage and possible sites at risk for future recurrences. However, it adds little to our current management of the disorder.

Treatment Results in Serpiginous Choroiditis and Multifocal Serpiginoid Choroiditis Associated with Latent Tuberculosis

Objectives:

To compare the results of systemic antitubercular therapy (ATT) and immunomodulatory therapy (IMT) in patients with serpiginous choroiditis (SC) or multifocal serpiginoid choroiditis (MSC).

Materials and Methods:

The clinical records of 28 patients with SC and MSC were reviewed. Patients were divided into 2 groups according to the treatment applied. Group 1 included 12 patients with MSC and 5 with SC treated with ATT and corticosteroid (CS); group 2 included 9 patients with MSC and 2 with SC treated with conventional IMT, interferon alpha-2a, and/or CS monotherapy.

Results:

In group 1, clinical remission was achieved in 12/12 MSC and 3/5 SC (total 15/17) patients with administration of ATT for 1 year. Two patients (1 SC, 1 MSC) had reactivation 2 and 7 months after cessation of ATT. Two patients with recurrence after completion of ATT and 2 patients resistant to ATT received IMT ± CS therapy. In group 2, clinical remission was achieved in 7/9 MSC and 2/2 SC (total 9/11) patients after 1 year of treatment. Recurrent inflammation was observed in 2 MSC patients 2 and 112 months after initiation of therapy, but responded well to local/systemic CS or IMT modification, and clinical remission was achieved in 7.8±4.3 months. Cumulative dose of CS was higher in group 2 (p=0.057). Nine of 12 MSC patients treated with ATT and 4/9 MSC patients treated with IMT achieved remission (p=0.203). One of 5 SC patients treated with ATT and 2/2 SC patients treated with IMT achieved remission (p=0.142).

Conclusion:

Although a statistically significant result could not be achieved in this small case series, our results suggest that ATT may be an appropriate first choice in the treatment of MSC associated with latent tuberculosis, and may be administered in patients with SC who are unresponsive to IMT.

Serpiginous choroiditis and infectious multifocal serpiginoid choroiditis

Serpiginous choroiditis (SC) is a posterior uveitis displaying a geographic pattern of choroiditis, extending from the juxtapapillary choroid and intermittently spreading centrifugally. The choroiditis involves the overlying retinal pigment epithelium, and the outer retina. This intraocular inflammation typically involves both eyes in otherwise healthy, middle-aged individuals with no familial or ethnic predilection. Pathogenesis is unclear; based on limited histopathologic studies, however, favorable response to immunosuppressive agents, and the absence of association with systemic or local infectious or noninfectious diseases, an organ-specific autoimmune inflammation seems likely to be the underlying process. Patients, particularly from tuberculosis-endemic regions, may present with fundus changes simulating SC, but show evidence of active tuberculosis and/or the presence of mycobacterial DNA in the aqueous humor. This has been referred to as serpiginous-like choroiditis, but we prefer the description multifocal serpiginoid choroiditis (MSC). We present the distinguishing features of SC and infectious multifocal serpiginoid choroiditis simulating SC. The distinction is crucial to avoid unnecessarily treating SC with antimicrobial agents. Advances in diagnostic and imaging modalities can help differentiate SC from MSC. Novel local and systemic treatment approaches improve the outcome and preserve vision in SC.

Clinical Features, Investigations, Management, and Prognosis of Serpiginous Choroiditis

Serpiginous choroiditis is an inflammatory form of posterior uveitis that affects the choroid, retinal pigment epithelium, and choriocapillaries. Known to be recurrent and progressive in nature, this bilateral disease can result in severe visual loss both during the active and healed stages. The age at onset is 40 to 50 years, but it can affect younger Indian population. It can be further classified into 3 types based on its clinical presentation, and they are, namely, peripapillary, macular, and ampiginous. Histological features further qualify the site of inflammation as evidenced by lymphocytic infiltration within the choroid and atrophy of choriocapillaries and retinal pigment epithelium. Despite a multitude of etiologies such as autoimmunity, infection, and degeneration, autoimmune causes remain the mainstay. Laboratory investigations can help rule out infections, whereas angiography can provide further insights into the progression of the disease. Newer investigations such as optical coherence tomography and fundus autofluorescence can help locate the lesion and identify the phase of the disease. Corticosteroids with immunosuppressives are the major management modality. Treatment of complications may require intravitreal injections, laser photocoagulation, or even vitreoretinal surgery.

Serpiginous choroiditis in a herpes-positive patient

BACKGROUND

Viruses are one of the most common causes of infections involving the posterior segment of the eye. Viral infections can be congenital or acquired and can affect the retina, choroid, or optic nerve. Herpes simplex virus has been implicated in a number of posterior segment conditions, including serpiginous choroiditis (SC), which has generally been described as idiopathic.

CASE REPORT

A 57-year-old black female presented with decreased and distorted vision in both eyes, of 10 months duration. Funduscopy revealed radial, deep grayish lesions emanating off of the optic disc in a peripapillary fashion. The clinical appearance was suggestive of SC, which was confirmed by fluorescein angiography. Serologic testing was positive for herpes simplex virus and thus may suggest a causative link between the virus and the choroiditis.

CONCLUSIONS

SC has been historically cited as an idiopathic process. There have been only rare reports linking this process with a viral etiology. Laboratory testing and clinical work-up needs to be obtained in any patient suspected of having SC, to detect a viral etiology. Treatment of an underlying condition may lead to optimum resolution in these patients.

Serpiginous Choroiditis

Serpiginous choroiditis is a rare, usually bilateral, chronic, progressive, recurrent inflammation of the choroid, retinal pigment epithelium, and choriocapillaris of unknown etiology. Based on clinical presentation, it can be classified into 1) peripapillary, 2) macular, and 3) ampiginous types. The clinical course, regardless of the presentation, is progressive with multiple recurrences leading to potentially significant visual loss. Visual outcome is directly related to the involvement of the para-fovea and fovea by the lesions or secondary choroidal neovascularization. The histological findings of the lesions are atrophy of the choriocapillaris, retinal pigment epithelium and photoreceptor cells, and moderate diffuse lymphocytic infiltrates throughout the choroid. Multiple etiologies including autoimmunity, infection, vasculopathy, and degeneration were proposed but none is well supported by clinical and laboratory evidence. Fluorescein and indocyanine green angiography have been useful in the assessment of the extent and the activity of lesions. Due to the insidious and progressive clinical course, an assessment of treatment outcomes needs long term follow-up. Currently, treatment with immunosuppressive and alkylating agents have shown possible efficacy in small case series. Larger clinical studies and interventional trials are required to further our understanding of the pathogenesis, etiology, and for the evaluation of treatment strategies.

The white dot syndromes

PURPOSE

To review the distinctive and shared features of the white dot syndromes, highlighting the clinical findings, diagnostic test results, proposed etiologies, treatments, and prognosis.

DESIGN

Review.

METHODS

Review of the literature.

RESULTS

Common white dot syndromes are reviewed, including acute posterior multifocal placoid pigment epitheliopathy, birdshot chorioretinopathy, diffuse unilateral subacute neuroretinitis, multiple evanescent white dot syndrome, multifocal choroiditis with panuveitis, serpiginous choroiditis, and acute zonal occult outer retinopathy.

CONCLUSIONS

The white dot syndromes are a group of disorders characterized by multiple whitish-yellow inflammatory lesions located at the level of the outer retina, retinal pigment epithelium, and choroid. For clinicians and researchers alike, they present significant diagnostic and therapeutic challenges.

Acute posterior multifocal placoid pigment epitheliopathy

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Autoimmune responsiveness to retinal IRBP, S-antigen and opsin in proliferative vitreoretinopathy

Proliferative vitreoretinopathy (PVR) was induced in rabbits by intravitreal injection of homologous fibroblasts. During the 8 weeks after injection the immune responsiveness to three purified retinal autoantigens was studied. From 2 weeks after injection, animals that developed serious forms of PVR exhibited definite mitotic responses of their lymphocytes to stimulation by the retinal antigens. These responses could consistently be demonstrated for S-antigen and interphotoreceptor retinoid-binding protein (IRBP) during the subsequent period of examination. Marked responses were also noted to opsin, however, their occurrence was more variable. In mild forms of PVR or in controls the responses were weak or absent. This showed that the elevated cellular reactivities were induced by the development of PVR and not by some other experimental factor. Humoral immune responses to the three antigens were absent (as assayed by ELISA). The control groups did not exhibit any elevated immune responsiveness. There appears to be accumulating evidence that inflammation may play a role in the development of PVR. The present results indicate that cellular autoimmune responses to photoreceptor antigens are a secondary phenomenon in PVR, nevertheless, they may be an important factor in the subsequent development of severe PVR. This autosensitization may consequently be taken into consideration in the treatment of complicated human PVR.