Differential Diagnosis of Viral-Induced Anterior Uveitis

Changes of peripheral blood Th cytokines in acute anterior uveitis and their relationships with recurrence

Acute anterior uveitis (AAU) can cause great pain to patients. Th cytokines in peripheral blood are significantly changed in these patients, including serum interleukin-23 (IL-23), interleukin-17 (IL-17), interleukin-4 (IL-4), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α) and transforming growth factor-β1 (TGF-β1) increase. However, the relationship between Th cytokines and recurrence of AAU is still unclear. Ninety-two cases of AAU were enrolled from January 2020 to April 2022 in our hospital (observation group). Levels of peripheral blood Th cytokines were detected, which were compared between acute and remission stages. After 6 months of follow-up, the relationships between Th cytokines in peripheral blood and recurrence in the observation group were analyzed. The prediction of Th cytokines on recurrence was analyzed. (1) The recurrence rate was 25.00%, and there were no statistical differences in the serum IL-23, IL-17, IL-4, IFN-γ, TNF-α and TGF-β 1 levels between patients with bilateral disease and unilateral disease (P < 0.05). (2) The serum IL-23, IL-17, IL-4, IFN-γ, TNF-α and TGF-β 1 levels of recurrence patients were higher than those of non-recurrence (t = 2.971, 5.357, 2.197, 2.766, 4.395, 2.983, P < 0.05). (3) The serum IL-23, IL-17, TNF-α levels were risk factors for recurrence (OR = 1.035, 1.210, 1.155, P < 0.05). (4) There were positive relationships between serum IL-23, IL-17, IL-4, IFN-γ, TNF-α and TGF-β 1 levels and recurrence (r = 0.317, 0.526, 0.248, 0.304, 0.480, 0.325, P < 0.05).            .

Anterior uveitis for the comprehensive ophthalmologist

Anterior uveitis presents a diagnostic challenge due to its wide array of etiologies and clinical manifestations. This narrative review aims to equip general ophthalmologists with a comprehensive understanding of anterior uveitis epidemiology, diagnosis, and treatment. Particular emphasis is placed on developing a tailored and stepwise strategy, rather than a one-size-fits-all approach, for the workup and treatment of anterior uveitis. Chest radiography and serologic testing for syphilis, human leukocyte antigen B27, and angiotensin-converting enzyme are appropriate routine investigations in cases of severe, bilateral, recurrent, or chronic anterior uveitis. Additional testing should be guided by clinical findings and regional epidemiology, especially when considering expensive and invasive modalities. Investigations that are obtained in the absence of clinical and epidemiologic orientation are of limited utility and incur significant costs to patients and health care systems. Most cases of anatomically isolated anterior uveitis resolve with topical corticosteroids, but some patients require escalation to systemic immunomodulatory therapy (IMT). IMT should be considered in patients who respond poorly to corticosteroids, develop side effects related to corticosteroids that limit their use, require high doses to maintain disease remission, or have concomitant systemic inflammatory disease. Comprehensive ophthalmologists should feel comfortable comanaging patients that require conventional disease-modifying antirheumatic drugs/antimetabolite therapy (i.e., methotrexate, azathioprine, and mycophenolate mofetil) with rheumatologists and providing guidance on ocular dosing. When uveitis quiescence cannot be achieved despite maximally tolerated antimetabolite therapy, patients should be referred to a uveitis specialist for consultation and consideration of IMT escalation. The timing of uveitis referral may depend on local factors specific to health care jurisdictions.

Comparison of Clinical Characteristics between Rubella Virus and Cytomegalovirus Associated Chronic Unilateral Anterior Uveitis

PURPOSE

To identify the clinical characteristics that may predict the diagnosis of Rubella virus (RV) or Cytomegalovirus (CMV) among cases of chronic treatment resistant or steroid dependent unilateral anterior uveitis (AU).

METHODS

Thirty-three consecutive patients with a diagnosis of CMV and 32 patients with RV chronic AU were enrolled. The respective frequency of certain demographic and clinical characteristics was compared between the two groups.

RESULTS

The presence of abnormal vessels in the anterior chamber angle (75% and 6.1%, respectively, p < .001), vitritis (68.8%-12.1%, p < .001), iris heterochromia (40.6%-15.2%, p = .022) and iris nodules (21.9%-3%, p = .027) were more common among RV AU. Conversely, intraocular pressure greater than 26 mmHg was more commonly encountered in CMV associated AU (63.6%-15.6%, respectively, p < .001) and large keratic precipitates were detected only in CMV-associated AU.

CONCLUSIONS

RV- and CMV-induced chronic AU differ significantly in the prevalence of specific clinical characteristics.

The Infectious Uveitis Treatment Algorithm Network (TITAN) Report 2-global current practice patterns for the management of Cytomegalovirus anterior uveitis

AIMS

To present current practice patterns in the diagnosis and management of Cytomegalovirus anterior uveitis (CMV AU) by uveitis experts worldwide.

METHODS

A two-round modified Delphi survey with masking of the study team was performed. Based on experience and expertise, 100 international uveitis specialists from 21 countries were invited to participate in the survey. Variation in the diagnostic approaches and preferred management of CMV AU was captured using an online survey platform.

RESULTS

Seventy-five experts completed both surveys. Fifty-five of the 75 experts (73.3%) would always perform diagnostic aqueous tap in suspected CMV AU cases. Consensus was achieved for starting topical antiviral treatment (85% of experts). About half of the experts (48%) would only commence systemic antiviral treatment for severe, prolonged, or atypical presentation. The preferred specific route was ganciclovir gel 0.15% for topical treatment (selected by 70% of experts) and oral valganciclovir for systemic treatment (78% of experts). The majority of experts (77%) would commence treatment with topical corticosteroid four times daily for one to two weeks along with antiviral coverage, with subsequent adjustment depending on the clinical response. Prednisolone acetate 1% was the drug of choice (opted by 70% of experts). Long-term maintenance treatment (up to 12 months) can be considered for chronic course of inflammation (88% of experts) and those with at least 2 episodes of CMV AU within a year (75-88% of experts).

CONCLUSIONS

Preferred management practices for CMV AU vary widely. Further research is necessary to refine diagnosis and management and provide higher-level evidence.

Cytomegalovirus Uveitis: Taiwan expert consensus

Cytomegalovirus (CMV) uveitis, a type of herpetic uveitis, is a major cause of infectious uveitis. Anterior and posterior CMV uveitis have diverse clinical presentations and treatment modalities. Based on expert consensus in Taiwan, this article provides suggestions regarding clinical manifestations, diagnosis, and treatment strategies for CMV uveitis based on clinical practice experience in Taiwan. CMV uveitis may have a distinct clinical presentation. Polymerase chain reaction (PCR) is an essential diagnostic tool to confirm a diagnosis. Antiviral therapy is the mainstay of treatment. Different agents, routes, and other supplemental treatments have been summarized and discussed in this article. Early diagnosis and appropriate treatment of CMV uveitis are crucial to avoid irreversible complications and vision loss. This consensus provides practical guidelines for ophthalmologists in Taiwan.

Interferon-gamma release assay and chest X-ray to classify intraocular tuberculosis among clinically undifferentiated uveitis

BACKGROUND Tuberculosis (TB) is a common cause of intraocular inflammation in Indonesia. As no accurate biomarker can confirm the diagnosis, ophthalmologists often rely on systemic findings, such as tuberculin skin test, interferon-gamma release assay (IGRA), and chest X-ray (CXR) for TB suspicion. This study aimed to evaluate IGRA and CXR in classifying intraocular TB among patients with a clinically undifferentiated cause of uveitis. METHODS This cross-sectional study included 116 patients (a total of 163 affected eyes) with a clinically undifferentiated cause of uveitis. IGRA and CXR were performed as part of the workup. Data on visual acuity, anterior chamber inflammation grade, and anatomical classification of uveitis were recorded. As there were no confirmed ocular tuberculosis (OTB) in our cases, eyes were classified into probable OTB, possible OTB, and unclassified. RESULTS Overall, 93 patients (80.2%) with a clinically undifferentiated cause of uveitis had positive IGRA, whereas 10 (8.6%) had CXR results suggestive of TB. More than one-third of the patients were blind (visual acuity <3/60), and panuveitis was the commonest anatomical classification. A trend was identified in patients with panuveitis, who often showed ≥2+ cell anterior chamber inflammation (p for trend = 0.023), according to OTB criteria (probable OTB = 3/4, 75.0%; possible OTB = 44/67, 65.7%; unclassified = 2/9, 22.2%). Furthermore, the clinically undifferentiated uveitis cases were eligible to be stratified into probable (8.6%) and possible (75.0%) OTB categories after IGRA and CXR examinations. CONCLUSIONS The combination of IGRA and CXR is valuable for classifying and diagnosing TB-related uveitis. A multidisciplinary approach is essential when the cause of uveitis is unknown.

Cytomegalovirus Anterior Uveitis: Clinical Manifestations, Diagnosis, Treatment, and Immunological Mechanisms

Little is known regarding anterior uveitis (AU), the most common ocular disease associated with cytomegalovirus (CMV) infection in immunocompetent populations. CMV AU is highly prevalent in Asia, with a higher incidence in men. Clinically, it manifests mainly as anterior chamber inflammation and elevated intraocular pressure (IOP). Acute CMV AU may resemble Posner-Schlossman syndrome with its recurrent hypertensive iritis, while chronic CMV AU may resemble Fuchs uveitis because of its elevated IOP. Without prompt treatment, it may progress to glaucoma; therefore, early diagnosis is critical to prognosis. Knowledge regarding clinical features and aqueous humor analyses can facilitate accurate diagnoses; so, we compared and summarized these aspects. Early antiviral treatment reduces the risk of a glaucoma surgery requirement, and therapeutic effects vary based on drug delivery. Both oral valganciclovir and topical ganciclovir can produce positive clinical outcomes, and higher concentration and frequency are beneficial in chronic CMV retinitis. An extended antiviral course could prevent relapses, but should be limited to 6 months to prevent drug resistance and side effects. In this review, we have systematically summarized the pathogenesis, clinical features, diagnostic and therapeutic aspects, and immunological mechanisms of CMV AU with the goal of providing a theoretical foundation for early clinical diagnosis and treatment.

Optical Coherence Tomography Angiography Findings of Iris Ischemia and Reperfusion in Cytomegalovirus Panuveitis

PURPOSE

To report a case of iris ischemia in an eye affected by Cytomegalovirus (CMV)-related Chronic Retinal Necrosis (CRN) with partial reperfusion after antiviral therapy demonstrated by optical coherence tomography angiography (OCTA).

METHODS

Retrospective case report. Multimodal imaging was performed at each follow-up visits.

RESULTS

At baseline, the clinical findings and PCR on aqueous confirmed the diagnosis of CMV-induced CRN, while OCTA and Fluorescein Angiography showed multi-sectoral retinal and iris non-perfusion. After three weekly intravitreal injections of Foscarnet and retinal photocoagulation, the clinical and angiographic picture improved, with partial reperfusion of both retinal and iris vasculature.

CONCLUSION

Retinal and iris non-perfusion in CRN can be partially reversible, if prompt treatment is administered. OCTA of the anterior segment allowed an accurate follow-up of the iris vasculature and its perfusion.

Aqueous Humor Analysis in Overlapping Clinical Diagnosis of Cytomegalovirus and Rubella Virus Anterior Uveitis

Background and Objectives: A cross-sectional single-center study was conducted to investigate the etiology in hypertensive anterior uveitis whose clinical features are not fully distinctive from cytomegalovirus or from rubella virus and to demonstrate the possible coexistence of both these viruses in causing anterior uveitis. Materials and Methods: The clinical charts of a cohort of patients with hypertensive viral anterior uveitis of uncertain origin consecutively seen in a single center from 2019 to 2022 were retrospectively reviewed; data on the clinical features, aqueous polymerase chain reaction, and antibody response to cytomegalovirus and rubella virus were collected. Results: Forty-three eyes of as many subjects with viral anterior uveitis of uncertain origin were included. Thirty-two patients had an aqueous polymerase chain reaction or antibody index positive to cytomegalovirus only, while 11 cases had an aqueous antibody response to both cytomegalovirus and rubella virus. This latter overlapping group had a statistically significant higher rate of hypochromia and anterior vitritis (p-value: 0.02 and < 0.001, respectively). Conclusions: The simultaneous presence of intraocular antibodies against cytomegalovirus and rubella virus could redefine the differential diagnosis of hypertensive viral anterior uveitis, demonstrating a possible “converged” immune pathway consisting in a variety of stimuli.

Viral Anterior Uveitis

Differential diagnosis of viral anterior uveitis (AU) based on the typical clinical findings (anterior chamber inflammation, morphology of the keratic precipitates, severity of IOP increase in relapse) is often straightforward. When differential diagnosis is difficult clinically, analysis of aqueous humour by PCR and/or antibody testing (Goldmann-Witmer coefficient) may be helpful. While both modalities are highly specific, they lack absolute sensitivity. Patients with HSV, VZV and CMV associated uveitis require both antiviral as well as antiinflammatory medication and often additional antiglaucomatous therapy, depending on IOP. In contrast, specific antiviral treatment is not possible in rubella associated AU and steroids should be administered with extreme caution due to their adverse effects. With all subtypes of virus associated AU, recurrent episodes put the patients at risk of developing secondary glaucoma, which often requires surgical treatment.

Construction of a mouse model of Posner-Schlossman syndrome by anterior chamber infection with cytomegalovirus

Accumulated clinical evidence has shown that Posner-Schlossman syndrome (PSS) is most likely the result of recurrent human cytomegalovirus (HCMV) infection in the anterior chamber (AC). Establishing an animal model is necessary to investigate the pathogenesis of PSS. In this study, we constructed a mouse model of (PSS) by injecting murine cytomegalovirus (MCMV) into the AC of BALB/c mice. Twenty-five BALB/c mice were divided into 5 groups. Smith strain MCMV expressing enhanced green fluorescent protein (EGFP) was passaged with mouse embryonic fibroblast (MEF). Right eyes in the 4 experiment groups received AC injection of 1 μL of virus solution with concentrations of 10³,10⁴,10⁵,10⁶ pfu/mL respectively, and the control group received only PBS. PSS-like signs (mutton-fat keratic precipitates (KP), pupil dilation, IOP elevation and corneal edema) were recorded 0-28 days post-injection (DPI). Sections of eyeballs from another 9 mice harvested on 0,10 and 28 DPI were examined to locate KP and the fluorescence signal of the virus. Reversible PSS-like signs except KP were observed in 20% and 60% mice of 10⁴ and 10⁵ groups while no PSS-like signs in the control and 10³ group; 80% in the 10⁶ group with partially unreversible signs till 28DPI. Much More fluorescent signals of virus in the iris and KP were found on 10DPI than 28 DPI, while no fluorescent signals and KP on 0DPI. The extent of PSS-like signs (pupil dilation, IOP elevation and corneal edema) was virus concentration-dependent (Spearman correlation coefficient, r = 0.830, = 0.475, = 0.662, p < 0.0001, <0.05, <0.001, respectively, n = 25). Success rate of PSS model (mice with PSS-like signs) was also virus concentration-dependent (Chi-square trend test, χ² = 6.828, df = 1, p < 0.01, n = 25). Our results indicate that AC injection of 1 μL MEF passaged MCMV (Smith strain) of 10⁴-10⁶ pfu/mL in BALB/c mice can be used to construct a mouse model of PSS. MCMV can infect iris tissue and replicate in it and then establish latency. This might account for the recurrent and self-limited nature of PSS.

Classification Criteria for Herpes Simplex Virus Anterior Uveitis

PURPOSE

The purpose of this study was to determine classification criteria for herpes simplex virus (HSV) anterior uveitis DESIGN: Machine learning of cases with HSV anterior uveitis and 8 other anterior uveitides.

METHODS

Cases of anterior uveitides were collected in an informatics-designed preliminary database, and a final database was constructed of cases achieving supermajority agreement on the diagnosis, using formal consensus techniques. Cases were split into a training set and a validation set. Machine learning using multinomial logistic regression was used in the training set to determine a parsimonious set of criteria that minimized the misclassification rate among the anterior uveitides. The resulting criteria were evaluated in the validation set.

RESULTS

A total of 1,083 cases of anterior uveitides, including 101 cases of HSV anterior uveitis, were evaluated by machine learning. The overall accuracy for anterior uveitides was 97.5% in the training set and 96.7% in the validation set (95% confidence interval: 92.4-98.6). Key criteria for HSV anterior uveitis included unilateral anterior uveitis with either 1) positive aqueous humor polymerase chain reaction assay for HSV; 2) sectoral iris atrophy in a patient ≤50 years old; or 3) HSV keratitis. The misclassification rates for HSV anterior uveitis were 8.3% in the training set and 17% in the validation set.

CONCLUSIONS

The criteria for HSV anterior uveitis had a reasonably low misclassification rate and appeared to perform well enough for use in clinical and translational research.

Classification Criteria for Varicella Zoster Virus Anterior Uveitis

PURPOSE

To determine classification criteria for varicella zoster virus (VZV) anterior uveitis.

DESIGN

Machine learning of cases with VZV anterior uveitis and 8 other anterior uveitides.

METHODS

Cases of anterior uveitides were collected in an informatics-designed preliminary database, and a final database was constructed of cases achieving supermajority agreement on the diagnosis, using formal consensus techniques. Cases were split into a training set and a validation set. Machine learning using multinomial logistic regression was used on the training set to determine a parsimonious set of criteria that minimized the misclassification rate among the anterior uveitides. The resulting criteria were evaluated on the validation set.

RESULTS

One thousand eighty-three cases of anterior uveitides, including 123 cases of VZV anterior uveitis, were evaluated by machine learning. The overall accuracy for anterior uveitides was 97.5% in the training set and 96.7% in the validation set (95% confidence interval 92.4, 98.6). Key criteria for VZV anterior uveitis included unilateral anterior uveitis with either (1) positive aqueous humor polymerase chain reaction assay for VZV; (2) sectoral iris atrophy in a patient ≥60 years of age; or (3) concurrent or recent dermatomal herpes zoster. The misclassification rates for VZV anterior uveitis were 0.9% in the training set and 0% in the validation set, respectively.

CONCLUSIONS

The criteria for VZV anterior uveitis had a low misclassification rate and seemed to perform sufficiently well for use in clinical and translational research.

Classification Criteria for Cytomegalovirus Anterior Uveitis

PURPOSE

To determine classification criteria for cytomegalovirus (CMV) anterior uveitis.

DESIGN

Machine learning of cases with CMV anterior uveitis and 8 other anterior uveitides.

METHODS

Cases of anterior uveitides were collected in an informatics-designed preliminary database, and a final database was constructed of cases achieving supermajority agreement on the diagnosis, using formal consensus techniques. Cases were split into a training set and a validation set. Machine learning using multinomial logistic regression was used on the training set to determine a parsimonious set of criteria that minimized the misclassification rate among the anterior uveitides. The resulting criteria were evaluated on the validation set.

RESULTS

One thousand eighty-three cases of anterior uveitides, including 89 cases of CMV anterior uveitis, were evaluated by machine learning. The overall accuracy for anterior uveitides was 97.5% in the training set and 96.7% in the validation set (95% confidence interval 92.4, 98.6). Key criteria for CMV anterior uveitis included unilateral anterior uveitis with a positive aqueous humor polymerase chain reaction assay for CMV. No clinical features reliably diagnosed CMV anterior uveitis. The misclassification rates for CMV anterior uveitis were 1.3% in the training set and 0% in the validation set.

CONCLUSIONS

The criteria for CMV anterior uveitis had a low misclassification rate and seemed to perform sufficiently well for use in clinical and translational research.

Long-term prognosis for glaucoma in patients with Posner-Schlossman syndrome

BACKGROUND

The aim of this study is to investigate the long-term prognosis for glaucoma in patients with Posner-Schlossman syndrome (PSS).

METHODS

In this retrospective case series study, a total of 98 patients with PSS from January 2014 to February 2019 were included in this study. Initial presentations and follow-up data were obtained from medical records. Vision-related quality of life (VR-QoL) was assessed using the 25-item National Eye Institute Visual Functioning Questionnaire.

RESULTS

Of the 98 patients included in the study, 66 (67%) presented with glaucoma, and among them, 21 (32%) required glaucoma surgery. The mean follow-up time was 50.1 months (range 1-263 months). Iris involvement was noted in 46 (46.9%) eyes; 26 (26.5%) had sectoral iris changes and 20 (20.4%) showed diffuse iris changes. Eyes with iris involvement had a significantly higher number of acute attacks of uveitis than those without (p = 0.010). The 5-year glaucoma surgery-free interval was 77.8% according to Kaplan-Meier analysis. Significant predictors of glaucoma surgery included iris involvement (hazard ratio [HR] = 5.215; confidence interval [CI] = 1.387-19.610), highest number of anti-glaucoma agents (HR = 5.069; CI = 1.848-13.905), baseline average retinal nerve fiber layer thickness (RNFLT) thickness (HR = 0.949; CI = 0.917-0.982), and disease duration (HR = 0.977; CI = 0.957-0.996). Overall complete surgical success and qualified success at 2 years was 35.3% and 75.5%, respectively. Patients with iris involvement, glaucoma surgery, and thinner average RNFLT had significantly poorer VR-QoL (all, p < 0.05).

CONCLUSIONS

Patients with PSS and glaucoma required glaucoma surgery in a high rate. Iris involvement increased the probability of surgical treatment and lowered the VR-QoL of PSS patients.

Viral anterior uveitis

Viral anterior uveitis (VAU) needs to be suspected in anterior uveitis (AU) associated with elevated intraocular pressure, corneal involvement, and iris atrophic changes. Common etiologies of VAU include herpes simplex, varicella-zoster, cytomegalovirus, and rubella virus. Clinical presentations can vary from granulomatous AU with corneal involvement, Posner-Schlossman syndrome, Fuchs uveitis syndrome, and endothelitis. Due to overlapping clinical manifestations between the different viruses, diagnostic tests like polymerase chain reaction and Goldmann-Witmer coefficient analysis on the aqueous humor may help in identifying etiology to plan and monitor treatment.

Clinical characteristics and prognostic factors in hypertensive anterior uveitis diagnosed with polymerase chain reaction

Aim of the study is to report the clinical characteristics and prognostic factors in hypertensive anterior uveitis (AU) diagnosed with multiplex polymerase chain reaction (PCR). Eighty-eight eyes of 88 patients with hypertensive AU were enrolled from 2015 to 2019 in a tertiary center in South Korea. All patients underwent multiplex PCR that was performed using aqueous humor samples collected at first visit to detect the DNA of six herpesviruses. Twenty-eight (31.8%) eyes were PCR positive. Herpes simplex virus was found in 6 (6.8%) eyes, varicella-zoster virus in 7 (8.0%) eyes, cytomegalovirus in 14 (15.9%) eyes, and Epstein–Barr virus in 1 (1.1%) eye. On multivariate regression analysis, PCR positivity was significantly associated with coin-shaped keratic precipitates (odds ratio (OR) = 6.01, P = 0.044). Recurrence and final visual acuity were significantly associated with a presumed diagnosis of viral endotheliitis (OR = 21.69, P = 0.04 and OR = 6.3, P = 0.004, respectively). This study showed the importance of PCR positivity, suggesting that identification of the virus through active PCR testing could affect the course, treatment, and prognosis of hypertensive AU.

Atypical associations of viral anterior uveitis with glaucoma-a series of challenging scenarios with review of literature

PURPOSE

To report unusual associations, atypical clinical presentations, and outcomes of tailored treatment of viral uveitis and glaucoma.

METHODS

Patients diagnosed with viral uveitis with associated glaucoma, seen at a tertiary eye care center between 2013 and 2020, were screened. Twenty-four patients with unclassified or atypical clinical presentations of viral uveitis, atypical clinical course, or with diagnostic challenges and associated glaucoma, were included. Patients with classical features of viral anterior or posterior uveitis, other forms of autoimmune/infectious/traumatic uveitis, were excluded.

RESULTS

Viral re-activation causing recurrent choroidals after glaucoma filtering surgery responsive to systemic antiviral therapy, massive pigment dusting/plume as a presenting feature, multiple progressive focal anterior synechiae similar to iridocorneoendothelial (ICE) syndrome, were seen in this cohort of unusual viral uveitis in glaucoma. A high index of suspicion helped diagnose a viral etiology in cases with high intraocular pressure (IOP) after uneventful Ahmed glaucoma valve surgery (AGV) or post-YAG capsulotomy laser, presumed Posner-Schlossman syndrome with multiple recurrences or presumed steroid glaucoma. All patients responded well with anti-viral and tailored concomitant steroids, anti-glaucoma therapy with loss of visual acuity seen in one eye developing optic atrophy.

CONCLUSIONS

Uncommon clinical presentations or associations of viral uveitis in glaucoma should be kept in mind. A high index of suspicion and tailored prompt treatment may ensure good outcomes preventing further visual morbidity in glaucoma.

Epidemiology of Viral Induced Anterior Uveitis

Purpose: Viral agents are the most common cause of infectious anterior uveitis worldwide. The purpose of this review is to analyze the frequency, gender and racial differences of viral anterior uveitis (VAU) in various populations.Methods: Systematized literature review of epidemiological reports of VAU cited in PubMed, EMBASE and the Cochrane Library database published until June 30th, 2020.Results: A total of 12 clinical studies on epidemiology of definite VAU and 36 clinical studies of presumed VAU were identified. Members of Herpesviridae family represent the most common causes of VAU. Other less frequently reported causes, such as rubella and endemic viruses (HTLV-1, Chikungunya, Dengue, Ebola, Zika virus) were also analyzed.Conclusion: HSV, VZV are prevalent worldwide. CMV is more frequent in Asia, and rubella in the West. However, due to globalization and air travel, HTLV-1, Chikungunya, Dengue and Ebola may become important causes of VAU across the world.

Association between temperature changes and uveitis onset in mainland China

BACKGROUND

Some uveitis subtypes show seasonal patterns. Whether these patterns are caused by seasonally varying temperatures or by other climatic factors remains unknown. This ecological research aimed to quantify the association between climate variability and uveitis onset.

METHODS

We combined data from the largest database of uveitis cases with surface climate data to construct panel data. We used choropleth maps to visually assess spatial uveitis variations.

RESULTS

Among 12 721 reports of uveitis originating from 31 provinces of mainland China from 2006 to 2017, we found that a 1°C increase in monthly temperature was associated with a rise in approximately 2 uveitis reports per 1000 individuals (95% CI 0.00059 to 0.0029). This association was present across all provinces, ranging in effect size from 0.0011 to 0.072 (95% CI 0.00037 to 0.10). A clear 0-3 months of cumulative lagging effect was noted across all types of uveitis, with the strongest effect for non-infectious uveitis (0.0067, 95% CI 0.0041 to 0.013). Stratified by age and sex, we found that men and people aged 20-50 years were more affected by temperature variations. Our model predicts that China might experience an increase in uveitis cases due to future global warming.

CONCLUSION

Our study is the largest-ever investigation of the association between uveitis and climate and, for the first time, provides evidence that rising temperature can affect large-scale uveitis onset. These results may help promote and implement policies to mitigate future temperature increases and the burden of disease caused by global warming.

A literature review on Fuchs uveitis syndrome: An update

Fuchs uveitis syndrome is a chronic, typically unilateral, ocular condition characterized by an asymptomatic mild inflammatory syndrome that can result in cataract and secondary glaucoma. Diagnosis is largely clinical because the etiology remains obscure. Fuchs uveitis syndrome is most likely the result of different insults or pathogenic mechanisms, including infections, autoimmune diseases, hereditary and sympathetic dysfunction. According to the infectious theory, the infection of herpes simplex virus, ocular toxoplasmosis, cytomegalovirus, rubella virus, and other viruses have been implicated in the pathogenesis of the disease. There is no indication for corticosteroid therapy in Fuchs patients, and treatment should be mostly reserved to cataract and glaucoma. Phacoemulsification with intraocular lens implantation is a safe procedure with good visual outcomes in patients with Fuchs uveitis syndrome. Glaucoma is often unresponsive to treatment and should actively be monitored both preoperatively and postoperatively in these patients. We discuss the current understanding of Fuchs uveitis syndrome from its clinical presentations through recommended management and provide a comprehensive description and the updated knowledge of its pathophysiology.