Beyond Joints: a Review of Ocular Abnormalities in Gout and Hyperuricemia

Evaluation of choroidal thickness and optic disc parameters in patients with chronic phase gout

PURPOSE

This study aims to assess the disparities in choroidal thickness and optic disc parameters between individuals diagnosed with chronic gout and an age- and gender-matched control cohort.

METHODS

This cross-sectional study involved 30 gout patients receiving treatment at the Rheumatology clinic, alongside 30 healthy control individuals matched for age and gender. A comprehensive ophthalmological assessment, encompassing visual acuity measurement, intraocular pressure evaluation, slit-lamp biomicroscopy, and dilated fundus examination, was conducted for all participants. Peripapillary retinal nerve fiber layer (RNFL), ganglion cell complex (GCC), and subfoveal choroidal thickness (SFCT) were quantified utilizing Spectral Domain Optical Coherence Tomography.

RESULTS

The mean age within the study group was 54.53 ± 9.43 years, while the control group's mean age was 53.20 ± 10.36 years. In both the gout and control cohorts, there were 28 men and 2 women. No significant differences were observed in age and gender between the groups. Gout patients manifested thinner RNFL and GCC across all quadrants; however, statistically significant thinning was only evident in the nasal and inferior quadrants for RNFL. Despite a thinner SFCT observed in gout patients compared to controls, this discrepancy did not attain statistical significance.

CONCLUSION

Chronic phase gout patients may display alterations in optic disc and macular parameters, alongside potential variations in choroidal thickness. Nevertheless, more controlled studies encompassing a larger participant pool are imperative to substantiate our findings.

Quality assurance in corneal transplants: Donor cornea assessment and oversight

The cornea is the most frequently transplanted human tissue, and corneal transplantation represents the most successful allogeneic transplant worldwide. In order to obtain good surgical outcome and visual rehabilitation and to ensure the safety of the recipient, accurate screening of donors and donor tissues is necessary throughout the process. This mitigates the risks of transmission to the recipient, including infectious diseases and environmental contaminants, and ensures high optical and functional quality of the tissues. The process can be divided into 3 stages: (1) donor evaluation and selection before tissue harvest performed by the retrieval team, (2) tissue analysis during the storage phase conducted by the eye bank technicians after the retrieval, and, (3) tissue quality checks undertaken by the surgeons in the operating room before transplantation. Although process improvements over the years have greatly enhanced safety, quality, and outcome of the corneal transplants, a lack of standardization between centers during certain phases of the process still remains, and may impact on the quality and number of transplanted corneas. Here we detail the donor screening process for the retrieval teams, eye bank operators. and ophthalmic surgeons and examine the limitations associated with each of these stages.

Predicting Risks of Dry Eye Disease Development Using a Genome-Wide Polygenic Risk Score Model

Purpose

The purpose of this study was to conduct a large-scale genome-wide association study (GWAS) and construct a polygenic risk score (PRS) for risk stratification in patients with dry eye disease (DED) using the Taiwan Biobank (TWB) databases.

Methods

This retrospective case-control study involved 40,112 subjects of Han Chinese ancestry, sourced from the publicly available TWB. Cases were patients with DED (n = 14,185), and controls were individuals without DED (n = 25,927). The patients with DED were further divided into 8072 young (<60 years old) and 6113 old participants (≥60 years old). Using PLINK (version 1.9) software, quality control was carried out, followed by logistic regression analysis with adjustments for sex, age, body mass index, depression, and manic episodes as covariates. We also built PRS prediction models using the standard clumping and thresholding method and evaluated their performance (area under the curve [AUC]) through five-fold cross-validation.

Results

Eleven independent risk loci were identified for these patients with DED at the genome-wide significance levels, including DNAJB6, MAML3, LINC02267, DCHS1, SIRPB3P, HULC, MUC16, GAS2L3, and ZFPM2. Among these, MUC16 encodes mucin family protein. The PRS model incorporated 932 and 740 genetic loci for young and old populations, respectively. A higher PRS score indicated a greater DED risk, with the top 5% of PRS individuals having a 10-fold higher risk. After integrating these covariates into the PRS model, the area under the receiver operating curve (AUROC) increased from 0.509 and 0.537 to 0.600 and 0.648 for young and old populations, respectively, demonstrating the genetic-environmental interaction.

Conclusions

Our study prompts potential candidates for the mechanism of DED and paves the way for more personalized medication in the future.

Translational Relevance

Our study identified genes related to DED and constructed a PRS model to improve DED prediction.

Lifestyle and Symptom Risk Factors for Dry Eye Disease in Asian Gout Population: A Population-Based Case-Control Study

We aim to investigate the lifestyle and symptom factors related to dry eye disease (DED) presence in patients with persistent gout using the Taiwan Biobank (TWB) database. A retrospective case-control study was conducted, and patients with a history of gout longer than 10 years were enrolled in the persistent-gout group. Each persistent-gout patient was age- and sex-matched to two non-gout individuals who served as the control group, and we included a total of 973 and 1946 patients in the persistent-gout group and non-gout groups. The main outcome of our study is the presence of DED and the distribution of several lifestyle and symptom risk factors of DED in persistent-gout and non-gout individuals. Logistic regression considering the age and sex and interaction test was applied to estimate the correlation of each lifestyle and symptom risk factor to DED in the two groups. A total of 95 and 140 DED events were found in the persistent-gout and non-gout groups, with a significantly higher percentage in the persistent-gout population (aOR: 1.167, 95% CI: 1.073-3.855, p = 0.0415). The visual display terminal (VDT) user (p = 0.0026) and persistent alcohol drinking (p = 0.0384) were associated with DED more often in the persistent-gout population than the non-gout population. Moreover, the percentages of DED in the patients with gout intervals of 10-20 years and more than 20 years were statistically insignificant (aOR: 1.042, 95% CI: 0.886-1.910, p = 0.5279). In conclusion, VDT usage and persistent alcohol drinking are prominent lifestyle and symptom risk factors for DED occurrence in patients who have experienced gout for more than 10 years.

Chronic kidney disease and its association with cataracts-A cross-sectional and longitudinal study

Introduction

We aim to explore the association between chronic kidney disease (CKD) and cataracts.

Methods

A total of 121,380 participants with adequate information collected from 29 community-based recruitment centers since 2008 were analyzed. The association between CKD and self-reported diagnosed cataracts was examined in a cross-sectional cohort and was validated in a longitudinal cohort of 25,263 participants without cataracts at baseline.

Results and discussion

Of all participants, cataracts occurred in 503/1,947 (26%) and 10,464/119,433 (9%) subjects in the CKD and non-CKD groups, respectively. Multivariate logistic regression showed that CKD was significantly associated with a higher prevalence of self-reported diagnosed cataracts. In the validation cohort, a higher incidence of cataracts was also noted in the CKD group (65/317, 21%) compared to the non-CKD group (1,964/24,252, 8%) during a mean 47-month follow-up. After adjusting for confounders, subjects with CKD had a 1.498-fold higher risk of incident cataracts than those without CKD (95% confidence interval = 1.114 to 2.013, p value = 0.007). We found that CKD was associated with a higher prevalence of cataracts as well as incident cataracts, which suggests CKD patients and their primary physicians should be aware of this disease and can provide a clue for further exploration of the possible mechanisms and treatments.

Identified risk factors for dry eye syndrome: A systematic review and meta-analysis

A meta-analytic approach was used to identify potential risk factors for dry eye syndrome. PubMed, Embase, and the Cochrane library were systematically searched for studies investigated the risk factors for dry eye syndrome from their inception until September 2021. The odds ratio (OR) with 95% confidence interval (CI) was calculated using the random-effects model. Forty-eight studies comprising 493,630 individuals were included. Older age (OR: 1.82; P<0.001), female sex (OR: 1.56; P<0.001), other race (OR: 1.27; P<0.001), visual display terminal use (OR: 1.32; P<0.001), cataract surgery (OR: 1.80; P<0.001), contact lens wear (OR: 1.74; P<0.001), pterygium (OR: 1.85; P = 0.014), glaucoma (OR: 1.77; P = 0.007), eye surgery (OR: 1.65; P<0.001), depression (OR: 1.83; P<0.001), post-traumatic stress disorder (OR: 1.65; P<0.001), sleep apnea (OR: 1.57; P = 0.003), asthma (OR: 1.43; P<0.001), allergy (OR: 1.38; P<0.001), hypertension (OR: 1.12; P = 0.004), diabetes mellitus (OR: 1.15; P = 0.019), cardiovascular disease (OR: 1.20; P<0.001), stroke (OR: 1.32; P<0.001), rosacea (OR: 1.99; P = 0.001), thyroid disease (OR: 1.60; P<0.001), gout (OR: 1.40; P<0.001), migraines (OR: 1.53; P<0.001), arthritis (OR: 1.76; P<0.001), osteoporosis (OR: 1.36; P = 0.030), tumor (OR: 1.46; P<0.001), eczema (OR: 1.30; P<0.001), and systemic disease (OR: 1.45; P = 0.007) were associated with an increased risk of dry eye syndrome. This study reported risk factors for dry eye syndrome, and identified patients at high risk for dry eye syndrome.

Artificial Intelligence in Predicting Systemic Parameters and Diseases From Ophthalmic Imaging

Artificial Intelligence (AI) analytics has been used to predict, classify, and aid clinical management of multiple eye diseases. Its robust performances have prompted researchers to expand the use of AI into predicting systemic, non-ocular diseases and parameters based on ocular images. Herein, we discuss the reasons why the eye is well-suited for systemic applications, and review the applications of deep learning on ophthalmic images in the prediction of demographic parameters, body composition factors, and diseases of the cardiovascular, hematological, neurodegenerative, metabolic, renal, and hepatobiliary systems. Three main imaging modalities are included—retinal fundus photographs, optical coherence tomographs and external ophthalmic images. We examine the range of systemic factors studied from ophthalmic imaging in current literature and discuss areas of future research, while acknowledging current limitations of AI systems based on ophthalmic images.

Prevalence of Monosodium Urate (MSU) Deposits in Cadavers Detected by Dual-Energy Computed Tomography (DECT)

Background: Dual-energy computed tomography (DECT) allows direct visualization of monosodium urate (MSU) deposits in joints and soft tissues. Purpose: To describe the distribution of MSU deposits in cadavers using DECT in the head, body trunk, and feet. Materials and Methods: A total of 49 cadavers (41 embalmed and 8 fresh cadavers; 20 male, 29 female; mean age, 79.5 years; SD ± 11.3; range 52–95) of unknown clinical history underwent DECT to assess MSU deposits in the head, body trunk, and feet. Lens, thoracic aorta, and foot tendon dissections of fresh cadavers were used to verify MSU deposits by polarizing light microscopy. Results: 33/41 embalmed cadavers (80.5%) showed MSU deposits within the thoracic aorta. 11/41 cadavers (26.8%) showed MSU deposits within the metatarsophalangeal (MTP) joints and 46.3% of cadavers demonstrated MSU deposits within foot tendons, larger than and equal to 5 mm. No MSU deposits were detected in the cranium/intracerebral vessels, or the coronary arteries. Microscopy used as a gold standard could verify the presence of MSU deposits within the lens, thoracic aorta, or foot tendons in eight fresh cadavers. Conclusions: Microscopy confirmed the presence of MSU deposits in fresh cadavers within the lens, thoracic aorta, and foot tendons, whereas no MSU deposits could be detected in cranium/intracerebral vessels or coronary arteries. DECT may offer great potential as a screening tool to detect MSU deposits and measure the total uric acid burden in the body. The clinical impact of this cadaver study in terms of assessment of MSU burden should be further proven.

Associations between Sjögren Syndrome, Sociodemographic Factors, Comorbid Conditions, and Scleritis in a Taiwanese Population-Based Study

This nationwide, population-based, retrospective, matched case–control study included 111,960 newly diagnosed patients with scleritis who were identified by the International Classification of Diseases, Ninth Revision, Clinical Modification code 379.0, selected from the Taiwan National Health Insurance Research Database. Demographic characteristics, Sjögren syndrome, and comorbid conditions within 1 year before the scleritis diagnosis were examined using univariate logistic regression analyses, and a paired t-test was used for continuous variables. Adjusted logistic regression was used to compare the prognosis odds ratio (OR) of the patients with scleritis with the controls. After adjustment for confounders, patients with Sjögren syndrome were remarkably more likely to have scleritis than the controls (OR = 33.53, 95% confidence interval (CI) = 27.43–40.97, p < 0.001). Other conditions found to have increased odds of scleritis included post ocular pterygium, glaucoma, and scleral surgery (OR  =  4.01, 95% CI  =  3.64–4.43; OR  =  3.16, 95% CI  =  2.24–4.47; OR  =  6.83, 95% CI  =  5.34–8.74, respectively); systemic infections, such as syphilis, tuberculosis, and a human herpes viral infection (OR  =  4.01, 95% CI  =  2.93–5.50; OR  =  2.24, 95% CI  =  1.94–2.58; OR  =  8.54, 95% CI  =  8.07–9.03, respectively); and systemic diseases, such as rheumatoid arthritis, granulomatous vasculitis, systemic lupus erythematosus, ankylosing spondylitis, and gout (OR  =  2.93, 95% CI  =  2.66–3.23; OR  =  7.37, 95% CI  =  3.91–13.88; OR  =  3.18, 95% CI  =  2.63–3.85; OR  =  5.57, 95% CI  =  4.99–6.22; OR  =  2.84, 95% CI  =  2.72–2.96, respectively). The results strongly support an association between Sjögren syndrome, post ocular surgery, systemic infection disease, systemic autoimmune disease, and scleritis.

Detection of signs of disease in external photographs of the eyes via deep learning

Retinal fundus photographs can be used to detect a range of retinal conditions. Here we show that deep-learning models trained instead on external photographs of the eyes can be used to detect diabetic retinopathy (DR), diabetic macular oedema and poor blood glucose control. We developed the models using eye photographs from 145,832 patients with diabetes from 301 DR screening sites and evaluated the models on four tasks and four validation datasets with a total of 48,644 patients from 198 additional screening sites. For all four tasks, the predictive performance of the deep-learning models was significantly higher than the performance of logistic regression models using self-reported demographic and medical history data, and the predictions generalized to patients with dilated pupils, to patients from a different DR screening programme and to a general eye care programme that included diabetics and non-diabetics. We also explored the use of the deep-learning models for the detection of elevated lipid levels. The utility of external eye photographs for the diagnosis and management of diseases should be further validated with images from different cameras and patient populations.

Tear Function Alterations and Conjunctival Impression Cytology Findings in Patients With Gout

OBJECTIVES

The aim of this study was to evaluate the tear functions and conjunctival impression cytology (CIC) findings of patients with gout and compare them with healthy controls.

METHODS

Thirty-four patients with gout (group 1) and 32 age-matched and gender-matched healthy individuals (group 2) were included in this cross-sectional study. Schirmer 1 test, tear breakup time (TBUT), Ocular Surface Disease Index (OSDI) score, and CIC grade were evaluated and compared between the groups.

RESULTS

There was no significant difference between the groups in gender and age (P=0.923 and P=0.078, respectively). The mean of Schirmer 1 test result was significantly lower in group 1 (9.74±6.03 mm) than that in group 2 (17.16±9.33 mm) (P<0.001). The TBUT was also significantly lower in group 1 (7.00±2.09 seconds) than that in group 2 (12.75±5.25 seconds) (P<0.001). The OSDI score (20.04±12.92) was significantly higher in group 1 than that in group 2 (6.19±10.07) (P<0.001). Although 10 patients (29.4%) in group 1 had the CIC grade of 2 to 3, none of the controls had CIC grade 2 to 3. The mean CIC grade in group 1 (1.15±0.89) was significantly higher than that in group 2 (0.47±0.51) (P<0.001).

CONCLUSIONS

The results of this study suggest that ocular surface alterations assessed by CIC and tear function abnormalities are more common in patients with gout.

Systemic diseases and the cornea

There is a number of systemic diseases affecting the cornea. These include endocrine disorders (diabetes, Graves' disease, Addison's disease, hyperparathyroidism), infections with viruses (SARS-CoV-2, herpes simplex, varicella zoster, HTLV-1, Epstein-Barr virus) and bacteria (tuberculosis, syphilis and Pseudomonas aeruginosa), autoimmune and inflammatory diseases (rheumatoid arthritis, Sjögren's syndrome, lupus erythematosus, gout, atopic and vernal keratoconjunctivitis, multiple sclerosis, granulomatosis with polyangiitis, sarcoidosis, Cogan's syndrome, immunobullous diseases), corneal deposit disorders (Wilson's disease, cystinosis, Fabry disease, Meretoja's syndrome, mucopolysaccharidosis, hyperlipoproteinemia), and genetic disorders (aniridia, Ehlers-Danlos syndromes, Marfan syndrome). Corneal manifestations often provide an insight to underlying systemic diseases and can act as the first indicator of an undiagnosed systemic condition. Routine eye exams can bring attention to potentially life-threatening illnesses. In this review, we provide a fairly detailed overview of the pathologic changes in the cornea described in various systemic diseases and also discuss underlying molecular mechanisms, as well as current and emerging treatments.

Elevated level of uric acid in aqueous humour is associated with posterior subcapsular cataract in human lens

IMPORTANCE

Age-related cataract is the leading cause of blindness worldwide. The pathological mechanisms causing this disease remain elusive.

BACKGROUND

To examine the involvement of uric acid (UA) in the pathogenesis of posterior subcapsular cataract (PSC).

DESIGN

Retrospective study and experimental investigation.

PARTICIPANTS

A total of 180 patients with PSC or non-PSC were included.

METHODS

Samples obtained from the patients were used to analyse content of UA and for histochemical examinations. The effects of UA on human lens epithelial cells were also investigated.

MAIN OUTCOME MEASURES

Aqueous humour UA and urate deposits.

RESULTS

The results showed a significant increase of aqueous humour UA in patients with PSC. After adjustment for potential confounders, elevated aqueous humour UA (odds ratio [OR] = 1.45) showed a stronger association with PSC than serum UA (OR = 1.10). Gomori methenamine silver staining revealed in PSC an intense deposit of urates in the lens fibres in equatorial regions, and in subcapsular fibres in posterior regions of the lens. Such staining was not detected in the lens with non-PSC. Treatment with UA-induced senescence and apoptosis in human lens epithelial cells in a dose dependent manner. Our results suggest that the elevated level of UA in aqueous humour causes a deposition of urates in human lens epithelium, which could possibly lead to dysfunction of these cells that generates opacification in PSC.

CONCLUSIONS AND RELEVANCE

These findings indicate the local action of excessive UA in the pathogenesis of PSC. Control of serum UA level could delay the progression of PSC.

An update on gout diagnosis and management for the primary care provider

Gout is the most common inflammatory arthritis in the US, affecting 3.9% of the population. Although many effective gout therapies are available for acute flares and chronic management, it is suboptimally treated worldwide, and recurrent gout flares can cause significant pain and irreversible joint damage.

Whole genome sequence analysis identifies a PAX2 mutation to establish a correct diagnosis for a syndromic form of hyperuricemia

Hereditary hyperuricemia may occur as part of a syndromic disorder or as an isolated nonsyndromic disease, and over 20 causative genes have been identified. Here, we report the use of whole genome sequencing (WGS) to establish a diagnosis in a family in which individuals were affected with gout, hyperuricemia associated with reduced fractional excretion of uric acid, chronic kidney disease (CKD), and secondary hyperparathyroidism, that are consistent with familial juvenile hyperuricemic nephropathy (FJHN). However, single gene testing had not detected mutations in the uromodulin (UMOD) or renin (REN) genes, which cause approximately 30-90% of FJHN. WGS was therefore undertaken, and this identified a heterozygous c.226G>C (p.Gly76Arg) missense variant in the paired box gene 2 (PAX2) gene, which co-segregated with renal tubulopathy in the family. PAX2 mutations are associated with renal coloboma syndrome (RCS), which is characterized by abnormalities in renal structure and function, and anomalies of the optic nerve. Ophthalmological examination in two adult brothers affected with hyperuricemia, gout, and CKD revealed the presence of optic disc pits, consistent with optic nerve coloboma, thereby revising the diagnosis from FJHN to RCS. Thus, our results demonstrate the utility of WGS analysis in establishing the correct diagnosis in disorders with multiple etiologies.

Detection of serum uric acid in primary open angle glaucoma: A pilot study

PURPOSE

To assess the association between the serum levels of uric acid (UA) and primary open-angle glaucoma (POAG).

METHODS

In this pilot study, 46 eyes of 23 patients with a clinical history of POAG and 30 eyes of 15 healthy subjects were included. All patients underwent a complete ophthalmological examination, including best corrected visual acuity (BCVA), intraocular pressure (IOP), and gonioscopy. Visual field parameters, such as mean deviation (MD) and pattern standard deviation (PSD), and optical coherence tomography (OCT) values of the optic nerve head, including retinal nerve fiber layer (RNFL) thickness and vertical cup/disc ratio (VCDR), were noted. A blood sample was collected from each subject for serum UA measurement.

RESULTS

IOP, MD, PSD, RNFL thickness, and VCDR resulted significantly different in POAG patients, when compared with controls (p < 0.05). POAG patients showed significantly lower levels of mean serum UA than healthy controls (4.00 ± 0.66 mg/dL vs 4.95 ± 0.86 mg/dL, respectively, p < 0.0001). Furthermore, severe POAG patients showed mean serum levels of UA lower than mild POAG patients (3.36 ± 0.70 mg/dL vs 4.22 ± 0.51 mg/dL, respectively, p = 0.01). Visual field and OCT parameters were statistically correlated with the mean serum levels of UA in POAG eyes (p < 0.05).

CONCLUSION

Results suggest that in POAG patients, serum UA levels may be decreased and correlated with visual field and OCT parameters worsening. Further larger multi-center prospective studies are necessary to confirm our findings and establish the role of UA in glaucoma.

Gout as a Risk Factor for Dry Eye Disease: A Population-Based Cohort Study

This study evaluated the effect of gout on the risk of dry eye disease (DED) by using the National Health Insurance Research Database (NHIRD). Data for 30,192 gout patients (21,081 men and 9111 women) and 30,192 non-gout patients (21,005 men and 9187 women) were analyzed. Approximately 1 million patients were randomly sampled from the NHIRD registry. After applying exclusion criteria, patients diagnosed with gout were enrolled in the study group. Thereafter, each individual in the study group underwent the matching process via the propensity score with another non-gout individual, which constituted the control group. The main outcome was defined as the development of DED in accordance with the corresponding International Classification of Diseases, Ninth Revision. In addition to DED, other risk factors including age, sex, and urbanization, and several co-morbidities were included in the multivariate model. The incidence of DED with the adjusted hazard ratio (aHR) and cumulative probability were evaluated in the gout and non-gout patients. A total of 2913 DED events were observed in the study group, whereas 2631 DED events were observed in the control group. A higher incidence rate ratio was found in the study group after adjustment (aHR: 1.065). Moreover, the cumulative probability indicated a significantly increased risk of DED in the study group (p = 0.001). The other potential risk factors of DED according to the multivariate analysis include older age, female gender, higher degree of urbanization, keratopathy, age-related macular degeneration, glaucoma, cataract, ischemic heart disease, hyperlipidemia, peripheral vascular disease, chronic pulmonary disease, rheumatic disease, peptic ulcer disease, liver disease, and malignancy. In conclusion, gout increased the risk of DED after adjustment, and the risk is positively correlated to a longer disease period.

Effect of Repeated Freeze-Thaw on Serum Biomarkers Associated with Eye Disease

Background

Serum biomarkers are associated with eye diseases, which results in the need for cryopreservation of serum samples. However, the effect on serum biomarker levels of repeatedly freezing and thawing remains poorly understood. The aim of this study was to evaluate the effects of repeated freeze-thaw on the serum levels of the protein, complement C3c (C3c), the micromolecule, uric acid (UA), and the enzyme, angiotensin-converting enzyme (ACE).

Material/Methods

Serum samples were obtained from 50 patients who attended an ophthalmic outpatient department. Following baseline measurements, the serum samples from each subject were divided into aliquots and stored at −80°C for further analysis, following between one to six freeze-thaw cycles. The serum levels of C3c, UA, and ACE were measured immediately after the stored serum samples were thawed.

Results

The serum level of C3c was significantly changed after the first freeze-thaw cycle (p<0.05), and a significant alteration in serum ACE levels occurred after the third freeze-thaw cycle (p<0.05). The serum UA level remained unchanged after all freeze-thaw cycles. Repeated freeze-thaw cycles significantly increased the serum levels of C3c and decreased the serum levels of ACE. The serum levels of C3c, UA, and ACE, respectively were significantly correlated (p<0.001), while the correlation coefficient for C3c and UA were improved when compared with ACE.

Conclusions

Repeated freeze-thaw can have variable effects on the serum levels of biomarkers, C3c, UA and ACE, which supports the need for quality control of cryopreserved serum for biomarker evaluation.

Autoimmunity, Autoinflammation, and Infection in Uveitis

PURPOSE

To review the pathogenesis of uveitis in light of recent advances in our understanding of innate and adaptive immune responses and their regulation.

DESIGN

Perspective.

METHODS

Methods included a review of prevailing views on the pathogenesis of uveitis and an analysis of developments in immunology that impact on its conceptual basis, particularly the concept of immunologic tolerance and its loss in autoimmunity. Importantly, the role of infection in the pathogenesis of uveitis is evaluated.

RESULTS

The results comprise a reappraisal of the pathogenesis of anterior vs posterior uveitis in the context of the blood-retinal barrier and its relation to autoimmune, autoinflammatory, and infectious uveitis. Autoimmunity is seen as a possible cause of certain forms of uveitis but definitive proof is lacking. Autoinflammatory disease, involving activated innate immune mechanisms, is considered causative in a second set of uveitis conditions. A place for infection in uveitis generally is proposed within a unifying concept for the pathogenesis of uveitis.

CONCLUSION

Infection may be implicated directly or indirectly in many forms of noninfectious or undifferentiated uveitis. In addition to the growing recognition that foreign antigen, including reactivatable infectious agents, might hide within ocular tissues, the possibility that a dysregulated microbiome might generate T cells that cause immune-mediated ocular inflammation has now been demonstrated experimentally. An uncontrolled, overexuberant host immune response may cause continuing irreversible tissue damage even after the infection has been cleared.

Serum uric acid concentration is associated with hypertensive retinopathy in hypertensive chinese adults

BACKGROUND

This cross sectional investigation included 12,966 subjects with hypertension, a cohort of the China Stroke Primary Prevention Trial (CSPPT), a randomized, multicenter clinical trial. This study aimed to explore the correlation between serum uric acid (SUA) concentration and hypertensive retinopathy in hypertensive adults.

METHODS

Diagnosis of hypertensive retinopathy was determined by non-mydriatic fundus photography and classified with Keith-Wagener-Barker (KWB) system. The correlation of SUA levels with hypertensive retinopathy prevalence and severity was assessed by statistical analysis.

RESULTS

9848 (75.95%) subjects were diagnosed with hypertensive retinopathy with the following retinopathy grade distribution: grade 1: 58.80%, grade 2: 14.81%, and grade 3-4: 2.34%. SUA levels were significantly associated with hypertensive retinopathy prevalence. Patients with hypertensive retinopathy had higher SUA levels than those without hypertensive retinopathy. Patients in the highest uric acid quartile had an odds ratio for hypertensive retinopathy of 1.21 compared to patients in the lowest uric acid quartile (OR = 1.21, 95% CI: 1.05-1.40, P = 0.008). When compared to the non-hyperuricemia group, those in the hyperuricemia group had an odds ratio for hypertensive retinopathy of 1.18(OR = 1.18, 95% CI: 1.05-1.33, P = 0.004). Every 1 mg/dl increase in uric acid concentration was significantly associated with a 6% higher odds of hypertensive retinopathy (OR = 1.06, 95% CI: 1.02-1.10, P = 0.002).

CONCLUSIONS

The prevalence of hypertensive retinopathy was high (75.95%) among hypertensives in our patients cohort. In addition, SUA concentration was significantly associated with hypertensive retinopathy.