Vitreous lavage fluid and bronchoalveolar lavage fluid have equal diagnostic value in sarcoidosis

Intraocular Immune Response in Human Uveitis: Time to Look Beyond Animal Models

PURPOSE

To review the current and future approaches to investigating the intraocular immune response in human uveitis.

DESIGN

Perspective.

METHODS

Review of currently available methods for investigating the immune response in ocular tissues and fluids in patients with intraocular inflammation/ uveitis. The advantages and disadvantages of human studies have been compared to those of animal models of uveitis.

RESULTS

Animal models, while being excellent tools for mechanistic studies, do not replicate the clinical and immunologic heterogeneity of human uveitis. Opportunities for immunological studies in human uveitis are mostly limited to histological studies, or sampling of intraocular fluids and peripheral blood. Histopathological studies can be enhanced by revisiting published historical data, tissue repositories, or autopsy specimens. Intraocular fluids can be investigated by a variety of techniques. Among these, flow cytometry and single-cell RNA sequencing (scRNAseq) provide single-cell resolution. While the current technology is costly and labor-intensive, scRNAseq is less limited by the low cellular yield from intraocular fluids and allows unbiased immune profiling enabling discovery of new cellular subsets. Immunological phenotypes uncovered from human data can be further investigated in animal studies.

CONCLUSION

The diversity of the intraocular immune response in uveitis patients remains challenging but can be studied by multiple techniques including histopathology, flow cytometry, and scRNAseq. Human data can be combined with animal studies for translating uveitis research into novel therapies.

Insights into the diagnosis and management of sarcoid uveitis: A review

Sarcoidosis is a leading cause of non-infectious uveitis that commonly affects middle-aged individuals and has a female preponderance. The disease demonstrates age, sex and ethnic differences in clinical manifestations. A diagnosis of sarcoidosis is made based on a compatible clinical presentation, supporting investigations and histologic evidence of non-caseating granulomas, although biopsy is not always possible. Multimodal imaging with widefield fundus photography, optical coherence tomography and angiography can help in the diagnosis of sarcoid uveitis and in the monitoring of treatment response. Corticosteroid remains the mainstay of treatment; chronic inflammation requires steroid-sparing immunosuppression. Features on multimodal imaging such as vascular leakage may provide prognostic indicators of outcome. Female gender, prolonged and severe uveitis, and posterior involving uveitis are associated with poorer visual outcomes.

Sarcoidosis-Related Uveitis: A Review

Sarcoidosis is an inflammatory disease that involves the eyes in 10-55% of cases, sometimes without systemic involvement. All eye structures can be affected, but uveitis is the most common ocular manifestation and causes vision loss. The typical ophthalmological appearance of these uveitis is granulomatous (in cases with anterior involvement), which are usually bilateral and with synechiae. Posterior involvement includes vitritis, vasculitis and choroidal lesions. Tuberculosis is a classic differential diagnosis to be wary of, especially in people who have spent time in endemic areas. The diagnosis is based on histology with the presence of non-caseating epithelioid granulomas. However, due to the technical difficulty and yield of biopsies, the diagnosis of ocular sarcoidosis is often based on clinico-radiological features. The international criteria for the diagnosis of ocular sarcoidosis have recently been revised. Corticosteroids remain the first-line treatment for sarcoidosis, but up to 30% of patients require high doses, justifying the use of corticosteroid-sparing treatments. In these cases, immunosuppressive treatments such as methotrexate may be introduced. More recent biotherapies such as anti-TNF are also very effective (as they are in other non-infectious uveitis etiologies).

[Sarcoid uveitis: Ophthalmologist's and internist's viewpoints]

Sarcoidosis is one of the leading causes of inflammatory eye disease. All ocular structures can be affected, but uveitis is the main manifestation responsible for vision loss in ocular sarcoidosis. Typical sarcoid anterior uveitis presents with mutton-fat keratic precipitates, iris nodules, and posterior synechiae. Posterior involvement includes vitritis, vasculitis, and choroidal lesions. Cystoid macular edema is the most important and sight-threatening consequence of sarcoid uveitis. Patients with clinically isolated uveitis at diagnosis rarely develop other organ involvement. Even though, ocular sarcoidosis can have a severe impact on visual prognosis, early diagnosis and a wider range of available therapies (including intravitreal implants) have lessened the functional impact of the disease, particularly in the last decade. Corticosteroids are the cornerstone of treatment for sarcoidosis, but up to 30% of patients achieve remission with requiring high-dose systemic steroids. In these cases, the use of steroid-sparing immunosuppressive therapy (such as methotrexate) is unavoidable. Among these immunosuppressive treatments, anti TNF-α drugs have been a revolution in the management of non-infectious uveitis.

Progress in the diagnosis of ocular sarcoidosis

Sarcoidosis is a multisystem granulomatous inflammation that affects multiple organ systems. The spectrum of extraocular and ocular involvement is wide and may precede systemic involvement. The diagnosis of ocular sarcoidosis relies on a combination of clinical findings, laboratory investigations, and radiographic findings. These include but are not limited to serum angiotensin-converting enzyme (ACE), lysozyme, plain-film radiographs of the chest, computed tomography (CT) scans of the chest, pulmonary function testing, bronchoalveolar lavage, and retinal imaging among others. In this review, we highlight current and evolving systemic investigations and approaches to ophthalmic imaging when considering the diagnosis of ocular sarcoidosis.

Characteristics and management of ocular sarcoidosis

Sarcoidosis is a chronic inflammatory disease of unknown etiology that affects many systemic organs, including the eye. The eye is the second most frequently affected organ in patients with sarcoidosis after lung disease. Approximately 30-50% of patients with systemic sarcoidosis develop uveitis, which is a sight-threatening intraocular inflammatory disorder. Sarcoidosis is the leading cause of uveitis in Japan and is one of the major clinical entities in many countries. Therefore, uveitis in association with sarcoidosis (ocular sarcoidosis) is considered essential in clinical practice in ophthalmology. The current review focuses on distinguishing features of ocular sarcoidosis, diagnosis, management, and discussion of the etiology of ocular sarcoidosis.

An update on the diagnosis and management of ocular sarcoidosis

PURPOSE OF REVIEW

Ocular sarcoidosis is one of the most common causes of uveitis worldwide. The diagnosis and treatment of patients with ocular sarcoidosis remains challenging in some cases. It is important for clinicians to keep up to date with new diagnostic and treatment tools for this disease.

RECENT FINDINGS

The International Workshop on Ocular Sarcoidosis diagnostic criteria were first proposed in 2009 and revised in 2017. The new criteria contained two parts: ocular presentation and systemic investigation. The diagnostic value of liver enzymes was reduced in the new criteria, whereas the value placed of lymphopenia and the CD4/CD8 ratio in bronchoalveolar lavage fluid were increased. Despite not being included in the criteria, recent studies have also highlighted the diagnostic value of serum soluble interleukin-2 receptors. Recent ophthalmologic imaging also provides useful insights for the differential diagnosis.Many new treatments for ocular sarcoidosis have been developed in recent years. The introduction of biological immunomodulatory agents for uveitis treatment represents a big improvement. Antitumor necrosis factor-alpha antibodies, including adalimumab, have been proven to be effective for treating ocular sarcoidosis. Many studies have also suggested that other biological agents could be effective and well tolerated. Newer intravitreal dexamethasone and fluocinolone implants have been developed. Patients treated with these implants have experienced good and sustained control of their intraocular inflammation.

SUMMARY

Diagnosis and treatment options for ocular sarcoidosis have changed over time. However, challenges still exist in some difficult patients. Future studies should focus on finding more sensitive biomarkers and developing more effective immunomodulatory treatments with longer efficacy and less side effects.

Ocular Sarcoidosis

Sarcoidosis is one of the leading causes of inflammatory eye disease. Any part of the eye and its adnexal tissues can be involved. Uveitis and optic neuropathy are the main manifestations, which may require systemic treatment. Two groups of patients with sarcoid uveitis can be distinguished: one of either sex and any ethnicity in which ophthalmological findings are various and another group of elderly Caucasian women with mostly chronic posterior uveitis. Clinically isolated uveitis revealing sarcoidosis remains a strictly ocular condition in a large majority of cases. Although it can be a serious condition involving functional prognosis, early recognition in addition to a growing therapeutic arsenal (including intravitreal implant) has improved the visual prognosis of the disease in recent years. Systemic corticosteroids are indicated when uveitis does not respond to topical corticosteroids or when there is bilateral posterior involvement, especially macular edema. In up to 30% of the cases that require an unacceptable dosage of corticosteroids to maintain remission, additional immunosuppression is used, especially methotrexate. As with other forms of severe noninfectious uveitis, monoclonal antibodies against tumor necrosis factor-α have been used. However, only very rarely does sarcoid uveitis fail to respond to combined corticosteroids and methotrexate therapy, a situation that should suggest either poor adherence or another granulomatous disease. Optic neuropathy often affects women of African and Caribbean origins. Some authors recommend that patients should be treated with high-dose of corticosteroids and concurrent immunosuppression from the onset of this manifestation, which is associated with a poorer outcome.

Revised criteria of International Workshop on Ocular Sarcoidosis (IWOS) for the diagnosis of ocular sarcoidosis

AIMS

International criteria for the diagnosis of ocular sarcoidosis (OS) was established by the first International Workshop on Ocular Sarcoidosis (IWOS) and validations studies revealed certain limitations of the criteria. To overcome the limitations, revised IWOS criteria was established in an international meeting. This manuscript was aimed at reporting the revised IWOS criteria.

METHODS

A consensus workshop was carried out to discuss and revise the IWOS criteria. The workshop was held on 27 April 2017, in Nusa Dua, Bali, Indonesia. Prior to the workshop, a questionnaire proposing revised criteria and consisting of one item for differential diagnosis, seven items for ocular clinical signs, 10 items for systemic investigations and three categories of diagnostic criteria was circulated to 30 uveitis specialists. Questionnaire items with over 75% support were taken as consensus agreement; items with below 50% support were taken as consensus disagreement and items with 50%-75% support were discussed at the workshop. Of the latter items, those supported by two-thirds majority in the workshop were taken as consensus agreement.

RESULTS

The survey and subsequent workshop reached consensus agreements of the revised criteria for the diagnosis of OS as follows: (1) other causes of granulomatous uveitis must be ruled out; (2) seven intraocular clinical signs suggestive of OS; (3) eight results of systemic investigations in suspected OS and (4) three categories of diagnostic criteria depending on biopsy results and combination of intraocular signs and results of systemic investigations.

CONCLUSIONS

Revised IWOS criteria were proposed by a consensus workshop.

Immune Profiling of T Cells Infiltrating Vitreous Humor in Tubercular Uveitis

PURPOSE

To assess cellular composition and local cytokine response in vitreous humor of tubercular uveitis.

METHODS

Cells were collected from vitreous cassettes and peripheral blood of 8 tubercular uveitis and 5 control subjects, undergoing vitrectomy and analyzed by flow cytometry for cellular composition, activation status, proinflammatory cytokine expression, and uptake of TLR9 ligand, CpG ODN 2216.

RESULTS

CD3 + T cells with equal proportion of CD4+ and CD8 + T cells formed major fraction of infiltrating cells. The vitreous humor showed higher expression of recent activation marker, CD69, and proinflammatory cytokines, IFN-γ and IL-17A, in CD4 + T cells as compared to peripheral blood. Lastly, intraocular CD4 + T cells showed reduced uptake of ODN 2216 than peripheral blood.

CONCLUSIONS

Our results indicate that local antigenic stimuli trigger T cell infiltration and activation of CD4 + T cells that are hyporesponsive to TLR9 stimulation. These infiltrating T cells might be responsible in further aggravating ocular inflammation.

Increased Aqueous Humor CD4+/CD8+ Lymphocyte Ratio in Sarcoid Uveitis

Purpose: To determine aqueous humor CD4+/CD8+ T-lymphocyte ratio changes in sarcoid and non-sarcoid uveitis with anterior chamber involvement. Methods: The case-control study includes 61 patients with either anterior uveitis, intermediate uveitis with anterior spill, or panuveitis. A total of 21 of them were categorized as sarcoid uveitis and 40 as non-sarcoid uveitis according to diagnostic criteria. CD4+/CD8+ ratio in the aqueous humor was determined using flow cytometry. Results: Significantly higher CD4+/CD8+ ratio in the aqueous humor was observed in patients with sarcoid uveitis (6.3 ± 1.4; mean ± SEM) compared to non-sarcoid uveitis (1.6 ± 0.1; mean ± SEM). Whole blood CD4+/CD8+ ratio was not elevated in subjects with sarcoid and non-sarcoid uveitis. Aqueous humor CD4+/CD8+ ratio >3.5 was observed to be associated with sarcoid uveitis (OR 38, 95% CI 7.0-205.2). Conclusion: Increased aqueous humor CD4+/CD8+ ratio in sarcoid uveitis. Immunophenotyping of localized lymphocytosis in aqueous humor could be utilized as an additional confirmatory marker for ocular sarcoidosis.

Comprehensive analysis of vitreous specimens for uveitis classification: a prospective multicentre observational study

PURPOSE

To determine the clinical relevance of vitreous biomarkers in patients with uveitis.

DESIGN

Multicentre, prospective, observational study.

SETTING

Uveitis outpatient clinics of two academic medical centres in Japan.

PATIENT POPULATION

This study included 234 eyes of 191 patients with various uveitis aetiologies: definitive sarcoidosis (61 eyes of 46 patients), suspected sarcoidosis (60 eyes of 45 patients), intraocular tumour (34 eyes of 27 patients), viral infection (20 eyes of 18 patients), non-sarcoidosis (16 eyes of 16 patients) and unknown aetiology (43 eyes of 39 patients).

OBSERVATION PROCEDURE

Vitreous samples (taken by pars planta vitrectomy) were analysed with flow cytometry, cytology and multiplex PCR analysis.

MAIN OUTCOME MEASURES

The primary outcome measures were the diagnostic values of various biomarkers (T cells, B cells and pathogen DNA) in vitreous samples. The secondary outcome was visual acuity after vitrectomy.

RESULTS

Sarcoidosis showed higher CD4/CD8 or CD4⁺ measurements than other aetiologies (p<0.01). In samples with viral infection, pathogen DNA was detected, and CD8⁺ counts were higher than the other aetiologies (p<0.01). Eyes with tumour had higher CD19⁺ (p<0.05). Non-sarcoidosis had lower CD4/CD8 than sarcoidosis, higher CD8⁺ than sarcoidosis and lower CD19⁺ than tumour (p<0.01). Unknown uveitis had lower CD4/CD8 than sarcoidosis (p<0.01), and higher CD4/CD8 than non-sarcoidosis, viral infection or tumour (p<0.001). Visual acuity improved after vitrectomy (p<0.001).

CONCLUSIONS

Uveitis aetiologies had distinct vitreous biomarker profiles, especially of infiltrating lymphocytes. Analyses of CD4/CD8 ratio, T-lymphocyte and B-lymphocyte subset, and pathogen DNA in vitreous samples have good safety profiles and high diagnostic value for uveitis classification.

TRIAL REGISTRATION NUMBER

UMIN000004980; Pre-results.

Ophthalmic and neuro-ophthalmic manifestations of sarcoidosis

PURPOSE OF REVIEW

Sarcoidosis is a multisystemic inflammatory disease that commonly affects the eye and less often the neuro-ophthalmic pathways. The manifestations can be quite variable but can have characteristic signs and clinical features. This review provides a comprehensive overview of the various ocular and neuro-ophthalmic manifestations of sarcoidosis, emerging diagnostic measures and approach to treatment. Particular focus is given to recent advances in diagnostic approach and available treatment options.

RECENT FINDINGS

Laboratory investigations, chest and nuclear medicine imaging remain important techniques for helping to diagnose sarcoidosis. Recent evidence suggests a role for aqueous humor analysis in the diagnosis of ocular sarcoidosis. Characteristic neuroimaging may help differentiate neurosarcoidosis from other causes. The role of blind conjunctival biopsy for suspected neurosarcoidosis is discussed. The emerging role and use of biologics is delineated for the treatment of both ocular and neuro-ophthalmic sarcoidosis.

SUMMARY

Sarcoidosis can affect any part of the visual system: the most common ocular manifestation is uveitis and the most common neuro-ophthalmic manifestation is optic neuropathy. Although diagnosis remains challenging, recent advancements in diagnosis are promising. Emerging biologics with particular efficacy for ocular and neuro-ophthalmic disease provide expanding treatment options for sight-threatening disease.