An Intraocular Inflammatory Profile of Rubella Associated Uveitis

Inflammatory cytokines as mediators of retinal endothelial barrier dysfunction in non-infectious uveitis

Characterised by intraocular inflammation, non-infectious uveitis includes a large group of autoimmune and autoinflammatory diseases that either involve the eye alone or have both ocular and systemic manifestations. When non-infectious uveitis involves the posterior segment of the eye, specifically the retina, there is substantial risk of vision loss, often linked to breakdown of the inner blood-retinal barrier. This barrier is formed by non-fenestrated retinal vascular endothelial cells, reinforced by supporting cells that include pericytes, Müller cells and astrocytes. Across the published literature, a group of inflammatory cytokines stand out as prominent mediators of intraocular inflammation, with effects on the retinal endothelium that may contribute to breakdown of the inner blood-retinal barrier, namely tumour necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-8, IL-17 and chemokine C-C motif ligand (CCL)2. This article reviews the function of each cytokine and discusses the evidence for their involvement in retinal endothelial barrier dysfunction in non-infectious uveitis, including basic laboratory investigations, studies of ocular fluids collected from patients with non-infectious uveitis, and results of clinical treatment trials. The review also outlines gaps in knowledge in this area. Understanding the disease processes at a molecular level can suggest treatment alternatives that are directed against appropriate biological targets to protect the posterior segment of eye and preserve vision in non-infectious uveitis.

Rubella virus-associated uveitis at a tertiary care hospital in Germany between 2013 and 2019

Uveitis is a process of intraocular inflammation that may involve different sections of the uveal tract. Apart from systemic or localized immune-mediated diseases, infections are key players in the etiology of uveitis and entail different treatment strategies. Rubella virus (RuV) is a recognized causative agent for the development of Fuchs uveitis, representing a major cause of virus-associated intraocular inflammation. A cohort of 159 patients diagnosed with different forms of uveitis between 2013 and 2019 was subjected to diagnostic antibody testing of the aqueous or vitreous humor. The diagnostic panel included RuV, cytomegalovirus, herpes simplex virus, varicella-zoster virus, and toxoplasmosis. Within this cohort, 38 RuV-associated uveitis (RAU) patients were identified based on a pathologic Goldman-Witmer coefficient indicative of an underlying RuV infection. With a mean age of 45.9 years, the RAU patients were younger than the non-RAU patients (56.3, p < 0.001). The evaluation of clinical parameters revealed a predominance of anterior uveitis and late sequalae such as cataract and glaucoma among the RAU patients. In 15 of the patients a history of prior RuV infections could be confirmed. The study underlines the importance of long-term surveillance of RuV associated diseases that originate from infections before the introduction of RuV vaccination programs.

Analysis of risk factors associated with secondary open-angle glaucoma in Posner-Schlossman syndrome: A retrospective case-control study

Background

Posner-Schlossman syndrome (PSS) is a relatively rare cause of chronic secondary open-angle glaucoma (OAG), but the exact cause is unknown. This study aimed to determine potential risk factors for OAG secondary to PSS and to provide a basis for early intervention in the development of PSS.

Methods

This was a retrospective case-control study. Nine cases diagnosed with PSS and seven cases diagnosed with OAG secondary to PSS were selected and their aqueous humor assays at the first occurrence of PSS were collected. Clinical characteristics including age, sex, disease duration, eye laterality, baseline visual acuity, maximum IOP, corneal endothelial cell density, visual field, retinal nerve fiber layer thickness, cup-to-disk ratio, keratic precipitates, anterior chamber inflammation, and aqueous humor cytokine assay results were compared between the two groups.

Results

The cytomegalovirus (CMV) positivity was 55.60% in patients with PSS and 100% in patients with OAG secondary to PSS. Corneal endothelial cell density was lower in patients with CMV-positive PSS (p = 0.0116). Concentrations of basic fibroblast growth factor (bFGF), interleukin (IL)-6, and vascular cell adhesion molecule (VCAM) in patients with PSS and IL-8, IL-6, and VCAM in patients with OAG secondary to PSS were higher than standard reference values; and IL-8 concentration was significantly higher in patients with OAG secondary to PSS (p = 0.0229). There were significant positive correlations between IL-8 and IL-6, IL-6 and VCAM (p = 0.0304, p = 0.0172) and a significant negative correlation between bFGF and vascular endothelial growth factor (VEGF) (p = 0.0497). Simultaneous increase of IL-8 and IL-6 concentration levels could be used as a cytokine indicator to predict secondary OAG in patients with PSS (p = 0.0095).

Conclusion

Simultaneous increase of IL-8 and IL-6 concentrations may be an important cause of accelerated secondary OAG in patients with PSS, with IL-8 playing a more critical role. IL-8 and IL-6 may be more reliable cytokine markers for predicting secondary OAG in PSS, However, the high possibility of secondary OAG in patients with CMV-positive PSS should not be ignored. Regulation of IL-8 and IL-6 levels may be a new strategy of preventing OAG secondary to PSS.

Complications of uveitis in a Spanish population, UveCAM study

OBJECTIVE

To estimate the population frequency of uveitis complications and to evaluate their main risk factors in the patients with uveitis from the UVECAM study.

PATIENTS AND METHODS

Development of complications in 386 patients with uveitis in the whole health area of the province of Toledo (UVECAM study) during a period of 1 year. Description of complications and study of their possible determinants by means of multivariate regression models.

RESULTS

Information on the development of complications was available in 371 of the 386 patients of the UVECAM study. The most frequent complications were posterior synechiae (19.0%), ocular hypertension (14.0%), macular edema (7.5%), epirretinal membrane (6.9%), glaucoma (6.6%), iridian atrophy (5.6%) and cataract (5.5%). The risk of complications increases with age, intermediate and panuveitis locations, and those of chronic or recurrent evolution.

CONCLUSION

Uveitis is associated with a high frequency of complications, especially in older patients, with intermediate or posterior localization of the inflammatory process and chronic or recurrent evolution.

Flow cytometric analysis of T lymphocytes and cytokines in aqueous humor of patients with varicella zoster virus-mediated acute retinal necrosis

BACKGROUND

The purpose of this study is to investigate the aqueous humor (AH) T lymphocyte subsets and cytokines of acute retinal necrosis (ARN) to elucidate the immunologic inflammatory features of this disorder.

METHODS

Three patients with ARN infected with varicella zoster virus (VZV) who underwent multiple intravitreal injections of ganciclovir were enrolled in this study. The control group consisted of four non-infectious patients with acute anterior uveitis (AAU). Flow cytometric analysis was performed on the lymphocyte subsets from the AH and peripheral blood (PB) samples during the active phase of intraocular inflammation. Five inflammatory cytokines were measured in each AH sample and various clinical characteristics were also assessed.

RESULTS

VZV deoxyribonucleic acid (DNA) was detected by real-time polymerase chain reaction (PCR) in AH from all the ARN patients, who showed higher CD8+ T lymphocytes population in AH than the AAU patients (p = 0.006). CD4/CD8 ratios of T lymphocytes and the percentage of CD8 + CD25+ T lymphocytes in AH were significantly lower in ARN than in AAU (p = 0.006; p = 0.012). In the ARN patients, the percentages of CD4+ and CD8+ T lymphocytes in AH were higher than those found in PB. The percentage of CD4 + CD25+ T lymphocytes in AH was significantly higher than the proportion in PB in the AAU patients (p = 0.001). Immunoregulatory cytokine Interleukin-10 in AH was significantly elevated in the ARN patients in comparison with the case of the AAU patients (p = 0.036). In ARN, the copy number of VZV DNA in AH positively correlated with the percentage of CD8+ T lymphocytes in AH and negatively correlated with the CD4/CD8 ratio in AH during the course of disease treatment (p = 0.009, r = 0.92; p = 0.039, r = - 0.834).

CONCLUSION

The ARN patients caused by VZV had different intraocular T lymphocyte subsets and cytokines profile than those of the non-infectious patients. High percentages of CD8+ T lymphocytes and low CD4/CD8 T cell ratios may be a potential biomarker for diagnosis of viral-infectious uveitis. T lymphocytes examination at the inflammatory sites has the potential to become a useful research tool for differentiating viral and non-viral uveitis.

Inflammatory markers of complete blood count in Fuchs uveitis syndrome

OBJECTIVE

To evaluate inflammatory indices of complete blood count (CBC) in patients with Fuchs uveitis syndrome (FUS), and to compare the results with healthy individuals.

DESIGN

Cross-sectional, comparative study.

PARTICIPANTS

A total of 140 participants were included in the study and divided into 2 groups: 70 patients diagnosed with FUS (FUS group) and 70 healthy individuals (control group).

METHODS

The groups were compared in terms of ocular examination findings and CBC parameters. The independent samples t test was used to examine variables between the groups. The Pearson correlation test was performed to analyze correlation among the severity of anterior chamber reaction, duration of FUS, and CBC indices.

RESULTS

The mean lymphocyte count and lymphocyte-to-monocyte ratio (LMR) were significantly higher in the FUS group than in the control group (p = 0.001 and p < 0.001, respectively). The mean monocyte count and neutrophil-to-lymphocyte ratio (NLR) were significantly lower in the FUS group than in the control group (p = 0.010 and p = 0.003, respectively). In the receiver operating characteristic curve analysis, the area under the curve (AUC) for LMR was 0.834, with a sensitivity of 82.6% and a specificity of 80.0%. The AUC for NLR was 0.789, with a sensitivity of 71.2% and a specificity of 70.0%. LMR was positively correlated with duration of FUS (p = 0.001, r = 0.574).

CONCLUSIONS

Our findings suggest that decreased NLR and increased LMR values may be markers indicating impaired blood-aqueous barrier function in FUS.

Alteration of MCP-1 and MMP-9 in Aqueous Humor Is Associated with Secondary Glaucoma in Fuchs Uveitis Syndrome

PURPOSE

To analyze changes in concentrations of pro- or anti-inflammatory cytokines, chemokines, or metalloproteinases (MMP) in the aqueous humor (AH) in Fuchs uveitis syndrome (FUS) patients with (FUSwG) or without (FUSwoG) secondary glaucoma.

METHODS

AH samples were collected from 43 eyes of Caucasian subjects (FUSwoG: n = 11; FUSwG: n = 8; control eyes: n = 24). Concentrations of IL-8, MCP-1, MMP-1,-2,-3,-9, SAA, TGFß-1,-2,-3, and TNF-α were measured by multiplex bead assay analysis.

RESULTS

Compared with the control group, levels of IL-8, MCP-1, MMP-3, and MMP-9 in the AH were significantly increased in FUSwG and FUSwoG patients. In contrast to FUSwoG patients, MCP-1 and MMP-9 level were lower in FUSwG, while expression of MMP-2, MMP-3, and TGFβ-1 was increased.

CONCLUSION

In our experiments, glaucoma in FUS patients was associated with low levels of MCP-1 and MMP-9 in the AH, while expression of MMP-2, MMP-3, and TGFβ-1 increased. The alteration in these molecular patterns may contribute to the development of glaucoma in FUS.