Epidemiological aspects of allergic conjunctivitis

Novel therapeutic receptor agonists and antagonists in allergic conjunctivitis

PURPOSE OF REVIEW

Allergic conjunctivitis is characterized by the development of pathophysiological changes to the ocular surface, which occurs when pro-allergic and pro-inflammatory mediators interact with their cognate receptors expressed on immune and nonimmune cells. Traditional treatments with antihistamines and corticosteroids provide relief, but there is a need for more efficacious and tolerable long-term therapy with a better safety profile. This article aims to provide an overview of the mode of action and clinical application of agonist therapies targeting glucocorticoid, melanocortin, and toll-like receptors, as well as antagonist therapies targeting cytokine, chemokine, integrin, and histamine receptors.

RECENT FINDINGS

There has been considerable advancement in immunology and pharmacology, as well as a greater understanding of the cellular and molecular mechanisms of allergic conjunctivitis. Recent research advancing therapy for allergic conjunctivitis has focused on developing synthetic molecules and biologics that can interfere with the process of the allergic immune reaction.

SUMMARY

This review discusses novel therapeutic receptors being explored agonistically or antagonistically to develop alternative treatment options for allergic conjunctivitis. These novel approaches hold promise for improving the management of allergic eye diseases, offering patients hope for more effective and safer treatment options in the future.

Association between short-term ozone exposure and allergic conjunctivitis in China: A multi-city case-crossover study

Short-term exposure to ozone has been linked to multiple allergic diseases, but the relationship between ozone exposure and allergic conjunctivitis (AC) remains unclear. This study aimed to investigate the association between short-term exposure to ozone and the risk of AC. We conducted a time-stratified case-crossover study across five Chinese cities from 2014 to 2022. Daily outpatient visit records for AC were identified in five hospitals using either the diagnosis name or ICD-10 code H10.1. Data on air pollution and meteorological conditions were also collected. We first examined the city-specific association between short-term ozone exposure and AC using conditional logistic regression. A random-effects meta-analysis was then conducted to obtain overall estimates. During the study period, 130,093 outpatient visits for AC occurred, with 58.8% (76,482) being male and 41.2% (53,611) female. A one-standard-deviation (SD) increase in ozone was associated with an 8.3% increase (95% CI: 3.8%, 13.0%) in AC outpatient visits. Similar positive associations were observed when adjusting for other pollutants (PM2.5, CO, SO2 and NO2) in two-pollutant and multi-pollutant models. Furthermore, the positive association remained consistent when using mixed-effects regression models or further adjusting for meteorological conditions. In addition, no effect modification of the AC-ozone association by sex, age and season was apparent. This study provides evidence supporting a positive association between short-term ozone exposure and AC risk in China. This highlights the potential value of mitigating ozone pollution to reduce the risk of ocular surface disorders.

JACQLQ subjective symptom questionnaire score and clinical test results for patients with allergic conjunctival disease

We investigated the relationship between subjective symptoms and objective findings in patients with allergic conjunctival diseases (ACD) and test results for tear total IgE (t-tIgE), conjunctival eosinophils (c-Eo), serum total IgE (s-tIgE), serum-antigen specific IgE (s-sIgE), and serum eosinophils (s-Eo). Subjective symptoms and objective findings of patients with ACD were evaluated using Japanese Allergic Conjunctival Disease Quality of Life Questionnaire (JACQLQ), which described disability score and emotional score written by patient and clinical findings score written by ophthalmologist. We investigated the relationship between questionnaire scores and laboratory data for t-tIgE, c-Eo, s-tIgE, s-sIgE, and s-Eo. Scores of impediments to life and of moods were highest in vernal keratoconjunctivitis among ACD. Cases with positive pollen-sIgE showed significantly more nasal symptom score than those with negative pollen-sIgE (P < 0.05). Cases with positive t-tIgE or c-Eo showed significantly more objective symptoms' JACQLQ score than those with negative t-tIgE or c-Eo (P < 0.05), respectively. Cases positive for house dust/mite-sIgE, showed significantly more objective symptoms' JACQLQ score than those without for house dust/mite-sIgE (P < 0.05). These results indicate that ACD could be analyzed more accurately by the combination of JACQLQ and laboratory data.

Allergic Conjunctivitis Management: Update on Ophthalmic Solutions

PURPOSE OF REVIEW

The aim of this review, is to present an updated revision of topical management of SAC and PAC, based on the available scientific evidence and focused on the impact of ophthalmic solution formulations on eye surface.

RECENT FINDINGS

Physicians treating ocular allergy should be aware of tear film and tear film disruption in SAC and PAC, and how eye drop composition and additives affect the physiology of the allergic eye. Seasonal and perennial allergic conjunctivitis (SAC and PAC) are the most frequent causes of ocular allergy (OA), and both conditions are underdiagnosed and undertreated. SAC and PAC are immunoglobulin E (IgE)-mediated hypersensitivity reactions. The additional tear film disruption caused by the release of inflammatory mediators increases and exacerbates the impact of signs and symptoms and may trigger damage of the ocular surface. Comorbidities are frequent, and dry eye disease in particular must be considered. Clinical guidelines for the management of SAC and PAC recommend topical therapy with antihistamines, mast cells stabilizers or dualaction agents as first-line treatment, but care should be taken, as many medications contain other compounds that may contribute to ocular surface damage.

Evaluation methods using tear volume in a conjunctivitis mice model

Allergic conjunctival disease is an immune-mediated inflammatory disease of the conjunctiva. To develop clinically useful drugs, it is necessary to develop quantitative evaluation methods that reflect the clinical symptoms in experimental animal models. Allergic conjunctivitis model mice were systemically sensitised with ovalbumin (OVA) administered intraperitoneally and locally sensitised with OVA eye drops between day 14-28. Next, conjunctivitis induced by ocular administration of OVA solution to sensitised mice was evaluated based on tear volume. Additionally, we evaluated increase in tear volume induced by direct ocular instillation of histamine, compound 48/80, and carrageenan. An increase in antigen-induced tear volume was observed in the mice model. Additionally, direct instillation of histamine, compound 48/80, and carrageenan increased tear volume. Furthermore, levocabastine inhibited the increase in tear volume in antigen-induced allergic conjunctivitis and histamine- and compound 48/80-induced conjunctivitis models. In contrast, betamethasone suppressed carrageenan-induced tear volume but not histamine- or compound 48/80-induced tear volume. Histamine may be involved in increased tear volume in allergic conjunctivitis. Betamethasone is not directly involved in the action of histamine and is thought to suppress increase in tear volume. Evaluation of tear volume in a conjunctivitis mice model is highly quantitative; therefore, it is possible to evaluate drug efficacy. This is considered a useful index compared with conventional methods.

Application of mendelian randomization in ocular diseases: a review

Ocular disorders can significantly lower patients' quality of life and impose an economic burden on families and society. However, for the majority of these diseases, their prevalence and mechanisms are yet unknown, making prevention, management, and therapy challenging. Although connections between exposure factors and diseases can be drawn through observational research, it is challenging to rule out the interference of confounding variables and reverse causation. Mendelian Randomization (MR), a method of research that combines genetics and epidemiology, has its advantage to solve this problem and thus has been extensively utilized in the etiological study of ophthalmic diseases. This paper reviews the implementation of MR in the research of ocular diseases and provides approaches for the investigation of related mechanisms as well as the intervention strategies.

Positive association between chlorinated paraffins and the risk of allergic diseases in children and adolescents

Contaminants may induce immune response polarization, leading to immune diseases, such as allergic diseases. Evidence concerning the effects of chlorinated paraffins (CPs), an emerging persistent organic pollutant, on immune system is scarce, particularly for epidemiological evidence. This study explores the association between CPs exposure and allergic diseases (allergic rhinitis, atopic eczema, and allergic conjunctivitis) in children and adolescents in the Pearl River Delta (PRD) in China. Herein, 131,304 children and adolescents from primary and secondary schools in the PRD were included and completed the questionnaire survey. The particulate matter (PM) samples were collected in the PRD and the PM2.5-bound CP concentrations were analyzed. In the multivarious adjustment mixed effect model (MEM), an IQR increase in ∑CPs was significantly associated with allergic diseases (rhinitis, eczema, and conjunctivitis) with the estimated odds ratios (ORs) for 1.11 (95% CI: 1.10, 1.13), 1.17 (95% CI: 1.15, 1.19), and 1.82 (95% CI: 1.76, 1.88), respectively. Interaction analysis indicated that overweight and obese individuals might have greater risk. Similar effect estimates were observed in several sensitivity analyses. This study provided epidemiological evidence on the immunotoxicity of CPs. More studies to confirm our findings and investigate mechanisms are needed.

Epidemiology of Pediatric Ocular Surface Inflammatory Diseases in the United States Using the Optum Labs Data Warehouse

PURPOSE

To benchmark the epidemiologic features of pediatric ocular surface inflammatory diseases (POSID).

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients 18 years of age or younger with a medical claim for a diagnosis of POSID in the Optum Labs Data Warehouse between 2007 and 2020.

METHODS

Patients with claims of blepharokeratoconjunctivitis (BKC), herpes simplex keratoconjunctivitis (HSK), or vernal keratoconjunctivitis (VKC) were included. Those with less than 6 months of follow-up before the initial diagnosis of POSID were excluded. Odds ratios (ORs) were derived from multivariable logistic regression analyses evaluating the associations between epidemiologic variables and POSID development.

MAIN OUTCOME MEASURES

The primary outcome was the estimated prevalence of POSID. Prevalence of POSID subtypes and changes in prevalence over time were also evaluated.

RESULTS

Two thousand one hundred sixty-eight patients with POSID were identified from 2018 through 2019, yielding an estimated prevalence of 3.32 per 10 000. The prevalence of POSID was higher among children between 5 and 10 years of age, male children, those of Asian descent, and those living in the Northeast and the West census regions of the United States. The prevalence (per 10 000) of BKC, HSK, and VKC in the same period were 0.59 (95% confidence interval [CI], 0.53-0.65), 0.74 (95% CI, 0.68-0.81), and 1.99 (95% CI, 1.88-2.10), respectively, and significant differences were found in terms of age, sex, racial, ethnic, and regional distributions among the diagnoses. Between 2008 through 2009 and 2018 through 2019, a significant increase in POSID was noted among Asians (from 6.26 [95% CI, 5.28-7.36] to 11.80 [95% CI, 10.40-13.34]) driven by changes in VKC. Multivariable analysis demonstrated that age older than 5 years (OR, 2.57-3.75; 95% CI, 2.17-4.34), male sex (OR, 1.38; 95% CI, 1.26-1.50), Asian descent (OR, 3.12; 95% CI, 2.70-3.60), and Black or African American descent (OR, 1.26; 95% CI, 1.02-1.55) were associated with POSID development.

CONCLUSIONS

This study provides an estimated prevalence of POSID and its 3 common subtypes in the United States, with important epidemiologic differences among them.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

The new preservative-free ophthalmic formulation of bilastine 0.6% preserves the ocular surface epithelial integrity in a comparative in vitro study

Allergic conjunctivitis (AC) is the most common form of allergic eye disease and an increasingly prevalent condition. Topical eye drop treatments are the usual approach for managing AC, although their impact on the ocular surface is not frequently investigated. The aim of this study was to perform a comparative physicochemical characterization, and in vitro biological evaluations in primary conjunctival and corneal epithelial cells of the new multidose preservative-free bilastine 0.6% and main commercially available eye drops. MTT assay was used to measure cell viability; oxidative stress was analyzed with a ROS-sensitive probe; and apoptosis was evaluated monitoring caspase 3/7 activation. Differences in pH value, osmolarity, viscosity and phosphate levels were identified. Among all formulations, bilastine exhibited pH, osmolarity and viscosity values closer to tear film (7.4, 300 mOsm/l and ~ 1.5-10 mPa·s, respectively), and was the only phosphates-free solution. Single-dose ketotifen did not induce ROS production, and single-dose azelastine and bilastine only induced a mild increase. Bilastine and single-dose ketotifen and azelastine showed high survival rates attributable to the absence of preservative in its formulation, not inducing caspase-3/7-mediated apoptosis after 24 h. Our findings support the use of the new bilastine 0.6% for treating patients with AC to preserve and maintain the integrity of the ocular surface.

Evaluation of Allergic Conjunctivitis Prevalence and Attitude Toward Prevention and Control in Saudi Arabia

BACKGROUND

Allergic conjunctivitis (AC) is a prevalent ocular condition with a substantial impact on individuals' quality of life. This study aimed to explore the demographic patterns, prevalence, symptoms, awareness, and attitudes associated with AC, while also examining potential associations with gender, age, and region of residence in Saudi Arabia.

METHODS

A cross-sectional study was conducted involving 487 participants. Data was collected through a self-administered questionnaire that included demographic information about AC prevalence, symptoms, attitudes, and awareness levels. Statistical analyses, including chi-square tests, were employed to examine associations between variables.

RESULTS

The study revealed a prevalence of AC (89, 18.3%) with common symptoms being eye redness (73, 82%) and itching (73, 82%). Participants displayed diverse awareness levels, with (376, 77.2%) correctly defining AC. The majority demonstrated either a good (230, 47.2%) or insufficient (196, 40.2%) attitude, while 54 (11.1%) had a sufficient attitude, and 7 (1.4%) exhibited an excellent attitude and awareness. Significant regional disparities were observed, impacting both prevalence and attitudes. While no gender differences were noted, the age group of 31-40 displayed a higher prevalence.

CONCLUSION

In this study, among 487 participants, the prevalence of AC was found to be 89 (18.3%). Meanwhile, attitude levels varied, with the majority demonstrating either a good or insufficient attitude. This provides valuable insights into the prevalence, symptoms, and awareness of AC in our population. The regional disparities underscore the need for tailored interventions addressing specific geographical contexts. The findings contribute to the broader understanding of AC, emphasizing the importance of targeted education and regional considerations in managing and preventing this condition.

Prevalence and risk factors of Vernal Keratoconjunctivitis among a Ghanaian clinical cohort: A case-control study

Background

Vernal Keratoconjunctivitis (VKC) has been determined to be highly prevalent in countries within the tropical climate region. However, little evidence from studies conducted within this region has been put forward to support this claim.

Aim

To determine the prevalence and risk factors of VKC among a Ghanaian clinical cohort.

Methods

A 3-year case-control study was conducted in a tertiary eye care institution, and medical records of patients who had been diagnosed of VKC between 2018 and 2021 were reviewed.

Results

Medical records of 3800 patients were reviewed. Some 359 cases of VKC were identified, with a population prevalence rate of 9.45 % . Males comprised 57.1 % of the population with VKC, with a male-to-female ratio of 1.33 : 1 . The disease was more prevalent (40.8%) in children (≤ 17 years), and the overall odds of incidence decreased by 10% for a unit increase in age. Age and sex-adjusted models revealed significant positive associations between Keratoconus [aOR = 40.760, 95% CI -5.948 to 339.937], Rhinitis [cOR = 5.183, 95% CI -2.074 to 12.022] and VKC. However, the incidence of VKC was relatively less expressive among pterygium cases [cOR = 0.315, 95% CI -0.077 to 0.846].

Conclusion

VKC is highly prevalent among children and is often associated with comorbidities of atopic origin that exacerbate the impact of the disease among this vulnerable population. It is imperative that clinicians provide holistic care for children with VKC.

[Current aspects of vernal and atopic keratoconjunctivitis]

BACKGROUND

Vernal keratoconjunctivitis (VKC) and atopic keratoconjunctivitis (AKC) are complex and rare diseases. Thus, their diagnosis and treatment are often a challenge.

OBJECTIVE

Discussion on the epidemiology, new pathogenetic concepts, interesting clinical findings, diagnostic possibilities and new treatment options and their side effects in severe ocular allergies. Analysis of the presentation of VKC in the internet.

MATERIAL AND METHODS

Evaluation of recent review articles, original publications, and case reports on the topics of VKC and AKC over the past 5 years.

RESULTS

Ocular allergies have significantly increased over the last decades. Recent concepts discussed in the pathogenesis of VKC and AKC are the role of the local and gut microbiome as well as the influence of neuroinflammation. Keratoconus is significantly more common in patients with VKC and AKC compared to the normal population. It is associated with faster progression and a more severe course of disease. A conjunctival provocation test is only rarely necessary in the diagnosis of allergic conjunctivitis. Treatment of atopic dermatitis with dupilumab, an interleukin 4 receptor alpha (IL-4Ra) antagonist, can cause ocular side effects. Unfortunately, information available on the internet for patients and parents on the topic of VKC is sometimes dangerously incorrect.

CONCLUSION

From the abovementioned new pathogenetic concepts, preventive and personalized treatment options could be developed in the future. Keratoconus in AKC/VKC must be recognized and treated early. Official guidelines are now available for a standardized conjunctival provocation test in the diagnosis of allergic conjunctivitis. The unwanted ocular side effects of dupilumab are often difficult to discriminate from the actual underlying AKC and respond well to anti-inflammatory treatment. Patients with VKC must be informed about the incorrect information on the internet regarding their disease.

Sensitization to Aeroallergens in a Mexican Cohort with Allergic Conjunctivitis: A Cross-sectional Retrospective Study Conducted in Ángeles Puebla Hospital

This study aims to evaluate the sensitization distribution of aeroallergens in patients with allergic conjunctivitis (AC) living in a temperate subhumid region and to describe the prevalence in a Mexican cohort. A total of 761 patient records were revisited, including the results of the skin prick test (SPT) for 45 aeroallergens. We found 292 patients with AC and a positive SPT in a 5-year period. The most frequent aeroallergens include dust mites (69.2% for Dermatophagoides pteronyssinus and 47.6% for Dermatophagoides farinae), trees (36% for cypress and 22.6% for ash), animals (33.9% for dogs and 26.7% for cats), and grasses (21.2% for Paspalum notalum and 19.9% for Poa pratensis). Among the studied population, a prevalence of 38.4% for the disease was calculated. House dust mites were responsible for most sensitizations found in the studied population. There is a high prevalence of AC in the selected cohort during the period studied.

Efficacy and Toxicity Evaluation of Bepotastine Besilate 1.5% Preservative-Free Eye Drops Vs Olopatadine Hydrochloride 0.2% Bak-Preserved Eye Drops in Patients with Allergic Conjunctivitis

Purpose

To study the efficacy and toxic effects of bepotastine besilate 1.5% preservative-free (BB-PF) and olopatadine 0.2% BAK-preserved (OL-BAK) drops on the ocular surface of patients with allergic conjunctivitis.

Patients and Methods

Ninety-seven patients with allergic conjunctivitis diagnosis participated in a prospective, multicenter, randomized, double-blind, controlled, parallel-group clinical trial. Patients received either BB-PF (n=48) or OL-BAK (n=49), both administered once daily in the morning. The patients were followed for 60 days. Ocular itching was the primary outcome measure. Secondary outcomes included ocular symptoms, signs, and non-ocular symptoms associated with rhinoconjunctivitis. Conjunctival impression cytology (CIC) was performed to evaluate histopathological changes related to the toxic effects of preservatives.

Results

BB-PF treatment was associated with a 1.30 more probability of diminished ocular itching than OL-BAK (odds ratio (OR)=1.30; 95% CI=(0.96-1.7); p=0.086). No statistically significant differences were found between treatments in the resolution of other ocular symptoms or signs, except for tearing, which was superior in the BB-PF (OR=1.37; 95% (1.26-1.47); p<0.0001). BB-PF was superior in terms of the resolution of rhinorrhea (p=0.040) and nasal itching (p=0.037). After 60 days of treatment, the BB-PF group exhibited 2.0 times higher probability of having a lower Nelson scale score compared to the OL-BAK group (OR=2.00; 95% CI=(1.19-3.34); p=0.010).

Conclusion

Both medications presented a similar efficacy in terms of the resolution of ocular signs and symptoms associated with ocular conjunctivitis. BB-PF is superior in the resolution of non-ocular symptoms and safer for the ocular surface than OL-BAK.

Nonlinear effects of humidex on risk of outpatient visit for allergic conjunctivitis among children and adolescents in Shanghai, China: A time series analysis

Background

Various epidemiological studies have focused on the adverse health outcomes of meteorological factors. However, there has been little research on the impact of humidex on allergic conjunctivitis, especially in child and adolescent populations. We aimed to explore the impact of humidex, a comprehensive index of relative humidity and temperature, on child and adolescent allergic conjunctivitis admissions.

Methods

Outpatient visit data for allergic conjunctivitis, meteorological factors and air pollutants in Shanghai for the 2017-2022 period were retrieved. For the purpose of analysing the nonlinear connection and lag impact between humidex and admissions for paediatric and adolescent allergic conjunctivitis, the distributed lag nonlinear model (DLNM) was fitted.

Results

A total of 147 090 cases were included in our cohort. We found a significantly nonlinear effect on humidex and allergic conjunctivitis. In the single-day lag pattern, the relative risks (RR) of allergic conjunctivitis were significant at lag 0 (RR = 1.08, 95% confidence interval (CI) = 1.05-1.11) to lag 2 (RR = 1.01, 95% CI = 1.00-1.01), lag 5 (RR = 1.01, 95% CI = 1.00-1.01) to lag 9 (RR = 1.01, 95% CI = 1.00-1.01), and lag 14 (RR = 1.02, 95% CI: 1.01-1.03). In the cumulative-lag day pattern, the RR of allergic conjunctivitis were significant at lag 0-0 (RR = 1.08, 95% CI = 1.05-1.11) to lag 0-14 (RR = 1.21, 95% CI = 1.13-1.28). We found that boys, children aged 7-17 years, and children in the warm season were more vulnerable to humidex. In addition, the highest attributable fraction (AF) and attributable number (AN) of humidex are at lag 0-14 (AF = 0.17, AN = 25 026).

Conclusions

Humidex exposure markedly increased the risk of allergic conjunctivitis, especially in highly high humidex. Appropriate public health management is needed for disease management and early intervention.

Impact of Kayumidas© app on subjective symptoms and treatment adherence in allergic Rhinoconjunctivitis: Prospective Single-Arm interventional pilot study

INTRODUCTION

In the spring of 2021, a physician-supervised application (app) "Kayumidas© - Itchy Eye Alert" was released for allergy sufferers, which implements a function to predict pollen dispersal status for each user based on weather forecasts and notify users of the results. This app provides push notifications of warning levels of itchiness and other symptoms, countermeasures, and the time to use medication. However, no evaluation has been conducted to determine whether the use of app improves compliance with treatment. This study aimed to verify whether the use of a smartphone app is effective in relieving the symptoms of allergic conjunctivitis and rhinitis and how it changes patients' eye drop behavior.

METHODS

This was an investigator-initiated, observational, prospective cohort study that was conducted between February 2022 and May 2022. In 62 patients diagnosed with allergic conjunctivitis, the scores of nine subjective eye and nose symptoms (1-4) and eye itchiness (1-7) before and after using the app were compared using a questionnaire. The adherence scores for eye drops (1-4) were also investigated using a questionnaire.

RESULTS

The scores for all five ocular subjective symptoms and all four nasal subjective symptoms improved significantly after app use (p < 0.01). Both itching scores (4.1 ± 1.1 vs. 1.6 ± 0.5, p < 0.01) and eye drop compliance scores (2.0 ± 0.7 vs. 3.9 ± 0.3, p < 0.01) improved significantly after app use.

CONCLUSION

The use of the Kayumidas© app improved adherence to eye drops and the subjective symptoms of allergic conjunctivitis and rhinitis. Thus, app use effectively improves symptoms by changing behavior and improving self-care awareness regarding treatment in patients with allergic diseases.

Classification of Subtypes of Vernal Keratoconjunctivitis by Cluster Analysis Based on Clinical Features

Background

Vernal keratoconjunctivitis (VKC) is a refractory ocular allergic disorder that mainly affects boys. A few studies have attempted to develop a classification of subtypes of VKC. In this study, we investigated a computational approach called cluster analysis to separate VKC cases into groups based on clinically relevant characteristics.

Methods

In total, 41 consecutive patients clinically diagnosed with VKC at the Department of Ophthalmology of Fukuoka University Hospital were included. Patients were treated with immunosuppressive eye drops without simultaneous corticosteroid eye drops, except for the occurrence of exacerbations. Collated variables were age at onset, clinical score of ocular lesions at baseline, clinical score of ocular lesions at final visit, clinical score of atopic dermatitis (AD) at baseline, frequency of exacerbations of VKC, serum total IgE level and peripheral blood eosinophil count.

Results

VKC patients were grouped into three clusters by cluster analysis, and cluster 1, 2, and 3 comprised 25, 9 and 7 cases, respectively. There were differences in the incidence of complications of AD and age at onset among the clusters; therefore, we named the three clusters for better understanding as traditional VKC (cluster 1), early-onset atopic keratoconjunctivitis (AKC)/VKC (cluster 2) and puberty-onset AKC (cluster 3).

Conclusion

We found in this study that VKC in childhood has three phenotypes which were previously unknown. Our findings may help to establish precision medicine by focusing on the phenotype of each case to develop individualized medicine to prevent exacerbations.

Management of vernal keratoconjunctivitis: Navigating a changing treatment landscape

Vernal keratoconjunctivitis (VKC) is a chronic, progressive, and potentially sight-threatening form of ocular inflammatory disease that primarily affects children and young adults. Prevalence varies by region, ranging from <2 per 10,000 in the United States to as high as 1,100 per 10,000 in parts of Africa. The rarity of VKC in developed countries can make differential diagnosis challenging, and treatment is often delayed until the disease is advanced, and symptoms are significantly impacting patients' quality of life. Although once viewed primarily as an immunoglobulin E-mediated condition, approximately 50% of patients with VKC do not exhibit allergic sensitization. It is now recognized that the immunopathology of VKC involves multiple inflammatory pathways that lead to the signs, symptoms, and conjunctival eosinophilic and fibroproliferative lesions that are a hallmark of the disease. We examine the evolution of our understanding of the immunopathology of VKC, the expanding VKC treatment armamentarium, the clinical implications of emerging treatment approaches, and future directions for VKC research and practice.

Prevalence and clinical characteristics of vernal keratoconjunctivitis in sub-Saharan Africa

PURPOSE OF REVIEW

Vernal keratoconjunctivitis (VKC) is a chronic bilateral allergic inflammatory disease of the conjunctiva and cornea that affects children and young adults, especially in sub-Saharan Africa. A limbal form (tropical endemic limbo conjunctivitis) is thought to be more common in the tropics where research on this vision-impairing condition is scanty. We sought to review current literature from sub-Saharan Africa, with a focus on the prevalence of VKC and its clinical presentation.

RECENT FINDINGS

There is a variable prevalence of VKC in SSA, up to 32.9% of children, especially in male individuals less than 5 years old, and has been diagnosed in a 4-month-old baby. Associated factors include exposure to dust, personal and family history of atopy, Vitamin D3 deficiency and HIV. The mixed form of VKC is the most frequent form seen and conjunctival pigmentation might be an early diagnostic sign.

SUMMARY

Childhood screening programs for VKC should be established to reduce the morbidity, decreased quality of life and school absenteeism that is seen in these patients. VKC-related research should be encouraged in this milieu to bring to light the particularities of VKC in SSA.

Atopic dermatitis in skin of colour. Part 2: considerations in clinical presentation and treatment options

Recent advances in atopic dermatitis (AD) present the condition as a heterogeneous disease of distinct endotypes across ethnic groups. AD in people with skin of colour may appear psoriasiform, lichenoid, scaly or papular, with a violaceous colour and there is a higher prevalence of post-inflammatory dyspigmentation compared with affected individuals of White ethnicity. These differences in clinical presentation may limit the use of AD assessment tools in people with skin of colour, leading to the potential for misdiagnosis and underestimation of severity, particularly in relation to assessment of erythema. Recent targeted therapies for AD have been studied in multiple ethnic groups; however, ethnicity-based subgroup analysis is often not performed. Further research is required to understand whether treatment responses or safety may differ among ethnic groups.

Effects of Punctal Occlusion on Ocular Itching and Conjunctival Redness Associated with Allergic Conjunctivitis

PURPOSE

Punctal occlusion using punctal plugs has been successfully used to treat the signs and symptoms of dry eye disease. However, the effects of punctal occlusion on the symptoms of allergic conjunctivitis (AC) have been less well documented. There is some concern among clinicians that punctal occlusion may make signs/symptoms of allergic conjunctivitis worse by trapping allergens on the eye. The objective of this post hoc analysis was to address this question and thus assess the effect of punctal occlusion alone on ocular itching and conjunctival redness associated with AC.

METHODS

This was a pooled post hoc analysis of three randomized, double-blind, placebo insert-controlled clinical trials in subjects with AC. Enrolled subjects were generally healthy adults with ocular allergies and a positive skin test reaction to perennial and/or seasonal allergens. The study used a modified version of the traditional conjunctival allergen challenge (CAC) model, which included multiple, repeated allergen challenges following placement of the intracanalicular insert. Subjects were rechallenged on Days 6, 7 and 8; Days 13, 14 and 15; and Days 26, 27 and 28.

RESULTS

The data set included 128 subjects that were administered placebo. Baseline mean (SD) ocular itching and conjunctival redness scores were 3.52 (0.44) and 2.97 (0.39), respectively. On post-insertion Days 7, 14 and 28, mean itching scores were 2.62, 2.26 and 1.91, respectively, representing 26%, 36% and 46% itching reductions, respectively (p < 0.001). On Days 7, 14 and 28, mean conjunctival redness scores were 1.98, 1.90, and 2.08, respectively, representing 33%, 36%, and 30% redness reductions, respectively (p < 0.001).

CONCLUSIONS

Based on this post hoc pooled analysis, punctal occlusion with a resorbable hydrogel intracanalicular insert did not worsen ocular itching or conjunctival redness in this patient population.

The Burden of Pediatric Visual Impairment and Ocular Diagnoses in Barbados

Visual impairment (VI) negatively affects a child's quality of life. The prevalence of VI in the Caribbean is nearly three times higher than in the United States, but the causes remain uncertain. This study leverages Barbados' unique eye care system to survey the eye diseases and VI prevalence in Barbadian children. Medical records of all patients aged <19 years who received ophthalmic care in Barbados' two public eye care centers between January and December 2019 were reviewed, capturing the entirety of public pediatric eye care within the study period. Age at the first visit to the clinic and at the final visit in 2019, sex, best-corrected visual acuity (BCVA), past medical history, and clinical diagnoses were extracted and analyzed. VI was defined as a BCVA of 6/12 or worse in the better-seeing eye. There were 3278 patient records with a mean age at the first visit of 7.8 ± 3.9 years. There were 80 (2.4%) children with VI, 62.5% of which were attributed to amblyopia. A total of 94% of VI was preventable or treatable. The most common diagnoses were refractive error (87.5%), strabismus (27.5%), and allergic eye disease (20.0%). Amblyopia is the major cause of pediatric VI in Barbados and is largely avoidable.

Topical cyclosporine A cationic ophthalmic emulsion in paediatric vernal keratoconjunctivitis: pooled analysis of randomised NOVATIVE and VEKTIS trials

BACKGROUND/OBJECTIVES

Cyclosporine A cationic ophthalmic emulsion (CsA CE) was evaluated in paediatric and adolescent patients with vernal keratoconjunctivitis (VKC) in the NOVATIVE (NCT00328653) and VEKTIS (NCT01751126) trials. The similarity of these studies permitted pooled assessment of the effect of CsA CE on corneal damage as well as safety and tolerability.

SUBJECTS/METHODS

Pooled outcomes were assessed for the first 28 days of treatment. In NOVATIVE, 118 patients were randomised to 4 times daily (QID) CsA CE 0.05%, 0.1%, or vehicle eye drops. In VEKTIS, 169 patients were randomised to CsA CE 0.1% QID or twice daily (BID) or vehicle. For these analyses, treatment groups comprised: (1) pooled CsA CE 0.1% QID arms (high-dose; n = 96); (2) pooled CsA CE 0.05% QID arm from NOVATIVE and CsA CE 0.1% BID data from VEKTIS (low-dose; n = 93); and (3) pooled vehicle QID arms (vehicle; n = 98).

RESULTS

Changes from baseline to day 28 (mean ± standard deviation) in corneal fluorescein staining (CFS) scores for CsA CE high-dose, low-dose, and vehicle groups were -1.6 ± 1.47 (95% CI: -0.9, -0.1; p = 0.0124 vs vehicle), -1.7 ± 1.39 (95% CI: -1.1, -0.3; p = 0.0015 vs vehicle), and -1.0 ± 1.55, respectively. Adverse events (AEs) of any type were reported in 37.5%, 34.4%, and 37.8% of the high-dose, low-dose, and vehicle groups, respectively. Most were mild or moderate in severity.

CONCLUSIONS

CsA CE significantly decreased corneal damage and was safe and well tolerated in patients with VKC. These data support CSA CE as a treatment option for the management of VKC.

Blocking Th2 Signaling Pathway Alleviates the Clinical Symptoms and Inflammation in Allergic Conjunctivitis

Purpose

To explore the role of Th2 signaling pathway in allergic conjunctivitis (AC).

Methods

Serum Th2 cytokines IL-4 or IL-13 of patients with AC were detected using the Meso scale discovery assay to verify the correlation of Th2 immunity and AC pathogenesis. Wistar Han rats were intraperitoneally and subcutaneously injected with ovalbumin (OVA) to establish an experimental AC model and the Th2 signaling pathway was blocked by an investigational neutralizing antibody (CM310). Serum IgE and OVA-specific IgE were detected by ELISA. Conjunctivitis inflammation, infiltration of eosinophils, and mast cell degranulation were detected by histological examination. Immortalized human conjunctival epithelial cells, a conjunctival epithelial cell line, and peripheral blood mononuclear cells of patients with AC were used as the target cells to study the impact of IL-4 or IL-13 on AC progression. Finally, a STAT6 reporter gene system was constructed using immortalized human conjunctival epithelial cells to confirm whether the downstream signaling pathway activated by IL-4 or IL-13.

Results

Serum IL-4 or IL-13 were increased in patients with AC versus healthy individuals. In an OVA-induced rat experimental AC model, blocking the Th2 signaling pathway with CM310, an investigational neutralizing antibody, alleviated the conjunctival symptoms, and decreased serum IgE, suppressed infiltration of eosinophils and mast cell degranulation. Further, an in vitro model showed CM310 suppressed the secretion of inflammatory cytokine from both immune cells and epithelial cells in both patients peripheral blood mononuclear cells and cell line.

Conclusions

Blocking Th2 signaling pathway alleviates the clinical symptoms and inflammation in AC.

TFOS Lifestyle Report: Impact of environmental conditions on the ocular surface

Environmental risk factors that have an impact on the ocular surface were reviewed and associations with age and sex, race/ethnicity, geographical area, seasonality, prevalence and possible interactions between risk factors are reviewed. Environmental factors can be (a) climate-related: temperature, humidity, wind speed, altitude, dew point, ultraviolet light, and allergen or (b) outdoor and indoor pollution: gases, particulate matter, and other sources of airborne pollutants. Temperature affects ocular surface homeostasis directly and indirectly, precipitating ocular surface diseases and/or symptoms, including trachoma. Humidity is negatively associated with dry eye disease. There is little data on wind speed and dewpoint. High altitude and ultraviolet light exposure are associated with pterygium, ocular surface degenerations and neoplastic disease. Pollution is associated with dry eye disease and conjunctivitis. Primary Sjögren syndrome is associated with exposure to chemical solvents. Living within a potential zone of active volcanic eruption is associated with eye irritation. Indoor pollution, "sick" building or house can also be associated with eye irritation. Most ocular surface conditions are multifactorial, and several environmental factors may contribute to specific diseases. A systematic review was conducted to answer the following research question: "What are the associations between outdoor environment pollution and signs or symptoms of dry eye disease in humans?" Dry eye disease is associated with air pollution (from NO2) and soil pollution (from chromium), but not from air pollution from CO or PM10. Future research should adequately account for confounders, follow up over time, and report results separately for ocular surface findings, including signs and symptoms.

TFOS Lifestyle: Impact of contact lenses on the ocular surface

Several lifestyle choices made by contact lens wearers can have adverse consequences on ocular health. These include being non-adherent to contact lens care, sleeping in lenses, ill-advised purchasing options, not seeing an eyecare professional for regular aftercare visits, wearing lenses when feeling unwell, wearing lenses too soon after various forms of ophthalmic surgery, and wearing lenses when engaged in risky behaviors (e.g., when using tobacco, alcohol or recreational drugs). Those with a pre-existing compromised ocular surface may find that contact lens wear exacerbates ocular disease morbidity. Conversely, contact lenses may have various therapeutic benefits. The coronavirus disease-2019 (COVID-19) pandemic impinged upon the lifestyle of contact lens wearers, introducing challenges such as mask-associated dry eye, contact lens discomfort with increased use of digital devices, inadvertent exposure to hand sanitizers, and reduced use of lenses. Wearing contact lenses in challenging environments, such as in the presence of dust and noxious chemicals, or where there is the possibility of ocular trauma (e.g., sport or working with tools) can be problematic, although in some instances lenses can be protective. Contact lenses can be worn for sport, theatre, at high altitude, driving at night, in the military and in space, and special considerations are required when prescribing in such situations to ensure successful outcomes. A systematic review and meta-analysis, incorporated within the review, identified that the influence of lifestyle factors on soft contact lens dropout remains poorly understood, and is an area in need of further research. Overall, this report investigated lifestyle-related choices made by clinicians and contact lens wearers and discovered that when appropriate lifestyle choices are made, contact lens wear can enhance the quality of life of wearers.

Conjunctival infiltrates and cytokines in an experimental immune-mediated blepharoconjunctivitis rat model

Purpose

To characterize the histopathological and immunological findings of a rat model of allergic blepharoconjunctivitis (BC) and demonstrate its potential utility for the assessment of BC therapies.

Methods

Sprague-Dawley (SD) rats were immunized with ovalbumin (OVA) and topically challenged with OVA (BC group) or PBS (control group), while a corticosteroid group was pre-treated with triamcinolone acetate 24 h before the challenge. Morphological features were evaluated and tissues were harvested for histological, flow cytometry and cytokine analysis.

Results

The BC group rats developed eyelid excoriations, redness, and conjunctival edema 24 h after the OVA challenge, while corticosteroid pre-treated and PBS-challenged rats were unaffected. The BC features were reduced despite repeated challenges for 5 days. Massive immune cell infiltration was observed in conjunctivae of BC rats, while no significant infiltration was seen in the other groups. Populations of T cells, mono-macrophages, neutrophils, and NK cells made up more than 77% of CD45⁺7AAD^- cells in the conjunctival tissues. T cell proportions were increased at 96 h compared to 24 h post-challenge, while macrophages decreased during the same time period. Eosinophils and intraepithelial neutrophils were detected in the BC rats, but not in the PBS and corticosteroid groups. BC eyes had significantly higher levels of IFN-γ and IL-2, while IL-4 and IL-6 levels were similar to controls.

Conclusion

A robust BC response was detected in this rat model which was suppressed by corticosteroid pre-treatment. Immune cell composition and cytokine profiles changed over time.

TFOS lifestyle: Impact of societal challenges on the ocular surface

Societal factors associated with ocular surface diseases were mapped using a framework to characterize the relationship between the individual, their health and environment. The impact of the COVID-19 pandemic and mitigating factors on ocular surface diseases were considered in a systematic review. Age and sex effects were generally well-characterized for inflammatory, infectious, autoimmune and trauma-related conditions. Sex and gender, through biological, socio-economic, and cultural factors impact the prevalence and severity of disease, access to, and use of, care. Genetic factors, race, smoking and co-morbidities are generally well characterized, with interdependencies with geographical, employment and socioeconomic factors. Living and working conditions include employment, education, water and sanitation, poverty and socioeconomic class. Employment type and hobbies are associated with eye trauma and burns. Regional, global socio-economic, cultural and environmental conditions, include remoteness, geography, seasonality, availability of and access to services. Violence associated with war, acid attacks and domestic violence are associated with traumatic injuries. The impacts of conflict, pandemic and climate are exacerbated by decreased food security, access to health services and workers. Digital technology can impact diseases through physical and mental health effects and access to health information and services. The COVID-19 pandemic and related mitigating strategies are mostly associated with an increased risk of developing new or worsening existing ocular surface diseases. Societal factors impact the type and severity of ocular surface diseases, although there is considerable interdependence between factors. The overlay of the digital environment, natural disasters, conflict and the pandemic have modified access to services in some regions.

International consensus statement on allergy and rhinology: Allergic rhinitis - 2023

BACKGROUND

In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document.

METHODS

ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work.

RESULTS

ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost.

CONCLUSION

The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment.

Factorial design-assisted reverse phase HPLC-UV approach for the concurrent estimation of cetirizine and azelastine in aqueous humor

A new analytical quality by design-assisted HPLC-UV approach is presented, for the first time, for the concurrent determination of cetirizine (CTZ) and azelastine (AZE) in raw materials, commercial eye drops and aqueous humor. The two drugs are co-administered as eye drops in severe ocular allergies. A 2³ full factorial design was adopted for the chromatographic optimization to ensure the best analytical performance and reliability, as well as to save time, effort and solvent consumption. The parameters, including pH, acetonitrile ratio, and flow rate, were selected as independent factors. The responses analyzed were resolution and tailing of peaks. The separation was achieved through isocratic elution on C8 column with mobile phase made up of acetonitrile: 0.3% triethylamine of pH 5 (60:40 v/v) at a flow rate of 1.2 mL min^-1 and detection at 216 nm. The elution time was less than 6 min. The approach was fully validated in accordance with International Council for Harmonization (ICH) guidelines. Good linearity was achieved over the concentration ranges of 1.0-30 and 0.5-10 µg mL^-1 with limits of detection of 0.310 and 0.158 µg mL^-1 and limits of quantification of 0.940 and 0.479 µg mL^-1 for CTZ and AZE, respectively, with correlation coefficients of 0.9998. The intra- and inter-day precisions were lower than 2%. The good sensitivity of the approach permits the analysis of CTZ and AZE in spiked aqueous humor with mean percentage recoveries of 100.93 ± 1.42 and 100.11 ± 1.55, respectively. The statistical comparison between results of the developed method and the comparison method revealed no differences, indicating the accuracy of the method.

Immune modulating nanoparticles for the treatment of ocular diseases

Ocular diseases are increasingly influencing people’s quality of life. Complicated inflammatory mechanisms involved in the pathogenic process of ocular diseases make inflammation-targeting treatment a potential therapeutic approach. The limited efficacy of conventional anti-inflammatory therapeutic strategies, caused by various objective factors, such as complex ocular biological barriers, and subjective factors, such as poor compliance, are promoting the development of new therapeutic methods. With the advantages of considerable tissue permeability, a controllable drug release rate, and selective tissue targeting ability, nanoparticles have successfully captured researchers’ attention and have become a research hotspot in treating ocular diseases. This review will focus on the advantages of nanosystems over traditional therapy, the anti-inflammation mechanisms of nanoparticles, and the anti-inflammatory applications of nanoparticles in different ocular diseases (ocular surface diseases, vitreoretinopathy, uveal diseases, glaucoma, and visual pathway diseases). Furthermore, by analyzing the current situation of nanotherapy and the challenges encountered, we hope to inspire new ideas and incentives for designing nanoparticles more consistent with human physiological characteristics to make progress based on conventional treatments. Overall, some progress has been made in nanoparticles for the treatment of ocular diseases, and nanoparticles have rather broad future clinical translation prospects.

Dysbiosis of Ocular Surface Microbiota in Patients With Refractive Allergic Conjunctival Diseases

PURPOSE

We investigated ocular surface microbiota dysbiosis in patients with refractory allergic conjunctival diseases (ACDs; stratified into mild and severe groups) treated with topical tacrolimus.

METHODS

Patients (n = 21) with refractory ACDs (including vernal and atopic keratoconjunctivitis) actively treated with topical tacrolimus and 6 healthy controls were evaluated. Based on clinical scores and expression of specific cytokines on the ocular surface, patients with ACDs were divided into mild and severe groups using cluster analysis. The microbial composition of tear specimens collected from patients with mild and severe ACD and control subjects using the Schirmer test paper was determined through next-generation 16S rRNA sequencing analysis.

RESULTS

Compared with healthy controls, patients with ACDs exhibited significantly decreased ocular surface microbiota α-diversity. Ocular surface microbiota mainly comprised members of the phyla Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria in all groups. The relative abundance of ocular surface microbiota in patients with ACDs was increased for phylum Firmicutes and decreased for phylum Proteobacteria (compared with control subjects). The genera Blautia (vs. mild ACD group) and Morganella (vs. control group) exhibited significantly increased abundance only in the severe ACD group.

CONCLUSIONS

The ocular surface microbiota in patients with severe ACD exhibited decreased diversity and exacerbation of dysbiosis compared with that in patients with mild ACD and control subjects. Patients with mild refractory ACD also exhibited decreased diversity of these microbiota. These alterations in microbiota indicated a change in the ocular surface of patients with refractory ACD (be it because of disease pathogenesis or topical immunomodulatory treatment).

Effects of air pollution on myopia: an update on clinical evidence and biological mechanisms

Myopia is one of the most common forms of refractive eye disease and considered as a worldwide pandemic experienced by half of the global population by 2050. During the past several decades, myopia has become a leading cause of visual impairment, whereas several factors are believed to be associated with its occurrence and development. In terms of environmental factors, air pollution has gained more attention in recent years, as exposure to ambient air pollution seems to increase peripheral hyperopia defocus, affect the dopamine pathways, and cause retinal ischemia. In this review, we highlight epidemiological evidence and potential biological mechanisms that may link exposure to air pollutants to myopia. A thorough understanding of these mechanisms is a key for establishing and implementing targeting strategies. Regulatory efforts to control air pollution through effective policies and limit individual exposure to preventable risks are required in reducing this global public health burden.

A mouse model of allergic conjunctivitis permitting tear eosinophil quantification

INTRODUCTION

Allergic conjunctivitis is an immune-mediated inflammatory disease of the conjunctiva that is induced by antigens. Allergic conjunctivitis can cause various symptoms such as ocular itching, hyperemia and edema. Developing experimental animal models that show clinical symptoms and methods for quantitative and objective evaluation is important for understanding allergic conjunctivitis. Therefore, this study aimed to develop an ovalbumin (OVA)-induced mouse model of allergic conjunctivitis and a useful method for evaluating symptoms of allergic conjunctivitis.

METHODS

ICR mice were sensitized by an intraperitoneal injection of OVA in PBS containing alum on days 0 and 5. Subsequently, local sensitization was then performed once daily from days 14 to 28, by instilling OVA in PBS into the both eyes. Drug treatment was administered once daily from days 14 to 28. Mice were randomly assigned topical treatment groups: Group 1, 0.1% betamethasone; Group 2, 0.025% levocabastine; Group 3 PBS (control).

RESULTS

Mice showed marked eye scratching behavior, hyperemia, edema, infiltration of eosinophils into tears and increased antigen-specific immunoglobulin E antibody levels in tears and the serum. These symptoms were inhibited by instillation of levocabastine and betamethasone, which are used clinically for the treatment of allergic conjunctivitis.

DISCUSSION

This method may be useful for evaluation of the symptoms of allergic conjunctivitis in experimental and clinical settings. In particular, the developed method, which measures the number of eosinophils in tears collected with phenol red threads, may enable the quantitative, objective, and noninvasive evaluation of the severity of allergic conjunctivitis.

Characteristic of red eye related diseases of Han and Uygur population in Urumchi compared with Shanghai, China

AIM

To study the characteristics, relative distribution and to compare causes of red eye in ophthalmic clinics in Urumchi and Shanghai, China.

METHODS

Data on continuous cases of red-eye patients admitted to the Ophthalmology Center of Xinhua Hospital Affiliated to Shanghai Jiao Tong University and the First Affiliated Hospital of Xinjiang Medical University were collected between November 2018 and September 2019. Demographic data, the incidence of red eye and related disease distribution of all cases were obtained. The independent t-test method was used for age comparison, while the Chi-square test was used to compare classified data information.

RESULTS

The information on 335 and 415 patients with red eyes in Shanghai and Urumchi were collected, respectively. The main causes of red eye were conjunctival disease and dry eye. The age of female patients with red eyes was significantly higher than that of males, and the proportion of female patients with dry eyes was also higher. Red-eye-related diseases occurred more frequently in patients over 46 years old than in those under 18, and dry eye was more common with increasing age. The incidence of infectious conjunctivitis in Urumchi was significantly higher than that in Shanghai, and allergic conjunctivitis occurred more frequently in spring, summer, or autumn than in winter (all P<0.05).

CONCLUSION

Significant differences exist in the distribution of red-eye-related diseases in Urumchi and Shanghai regions of China, and distribution varies with age and season, the latter being an important feature of allergic conjunctivitis.

A time-series analysis on generalized additive model for atmospheric pollen concentration and the number of visits of allergic conjunctivitis, Beijing, China

The objective of this study is to investigate the correlation between atmospheric pollen concentration and daily visits for allergic conjunctivitis. Daily counts of outpatient visits for allergic conjunctivitis, atmospheric pollen concentration, and meteorological data during pollen season of 2018 and 2019 were collected from Beijing Shijitan Hospital, China. A time-series analysis on generalized additive model with Poisson distribution was used to estimate the relationship between pollen concentration and visits for allergic conjunctivitis, after controlling for the time trend, weather variables, day of the week, and holiday effect. The RStudio was used to generate Spearman correlation coefficients and then to plot the lag-response curves for specific and incremental cumulative effects of relative risk (RR). There was a moderate positive correlation between pollen concentration and visits for allergic conjunctivitis, and Spearman's correlation coefficient was 0.521 in 2018 and 0.515 in 2019 (P<0.01). The specific cumulative effect peak associated with per 10 grains/kmm² increases of atmospheric pollen concentration was within 0 day, and the lag time was 8 days(2018, 2019). The incremental cumulative effect peak associated with per 10 grains/kmm² increases of atmospheric pollen concentration occurred on lag day 10 (2018) and lag day 8 (2019), and the lag time was 14 days (2018) and 20 days (2019). Elevated concentrations of pollen increase the risk of allergic conjunctivitis with a time lag effect.

Diagnosis, Management, and Treatment of Vernal Keratoconjunctivitis in Asia: Recommendations From the Management of Vernal Keratoconjunctivitis in Asia Expert Working Group

Vernal keratoconjunctivitis (VKC) is an underdiagnosed and underrecognized ocular surface disease with limited epidemiological data in Asia. It is more prevalent in warm, dry, and windy climates, and often has a substantial impact on a patient’s quality of life. In rare cases, VKC can be associated with vision loss, either through corticosteroid overuse or inadequate treatment of persistent inflammation. As a potentially severe and complex disease, there is variability with how VKC is managed across Asia and among the various allergic eye diseases. Diagnosis and treatment of patients with VKC is a challenge for many ophthalmologists, since no precise diagnostic criteria have been established, the pathogenesis of the disease is unclear, and anti-allergic treatments are often ineffective in patients with moderate or severe disease. In addition, the choice of treatment and management strategies used for patients varies greatly from country to country and physician to physician. This may be because of a lack of well-defined, standardized guidelines. In response, the Management of Vernal Keratoconjunctivitis in Asia (MOVIA) Expert Working Group (13 experts) completed a consensus program to evaluate, review, and develop best-practice recommendations for the assessment, diagnosis, and management of VKC in Asia. The expert-led recommendations are summarized in this article and based on the currently available evidence alongside the clinical expertise of ophthalmologists from across Asia with specialism and interest in the ocular surface, VKC, and pediatric ophthalmology.

Use of Ketotifen Fumarate-Eluting Daily Disposable Soft Contact Lens in Management of Ocular Allergy: Literature Review and Report of Two Cases

We present two cases in which the drug-eluting daily disposable soft contact lens (DDSCL) Acuvue® Theravision^TM with Ketotifen (Johnson & Johnson Vision Care, Inc., Jacksonville, Florida, USA) (ATK), which contains the anti-allergic drug ketotifen fumarate, alleviated ocular allergic symptoms. Case 1 was a 57-year-old woman with a history of allergic conjunctivitis in the spring and fall. In the summer and winter, the patient used frequent replacement soft contact lenses, but in the allergy seasons, she used DDSCLs in combination with anti-allergic eye drops. She agreed to start wearing ATK lenses from before the next fall season. The lenses suppressed her allergic signs and symptoms, and she felt comfortable wearing them and continued their use throughout the season. Her symptoms were suppressed, providing her comforts that enabled uses of the CLs for some time. She successfully used the lenses again from the beginning of the next spring season. Case 2 was a 31-year-old woman with a history of cedar pollinosis. The patient previously used DDSCLs and was prescribed ATK lenses at her regular clinic. About one month later, she was referred to our department. With ATK lenses, she did not experience any subjective symptoms during the pollinosis season. At a subsequent visit, hyperemia had decreased compared with the initial visit. In these two cases, the use of ATK lenses from before until the end of both the spring and fall allergy seasons suppressed the symptoms of allergic conjunctivitis, allowing the patients to continue to wear contact lenses.

Correlation between air pollution and prevalence of conjunctivitis in South Korea using analysis of public big data

This study investigated how changes in weather factors affect the prevalence of conjunctivitis using public big data in South Korea. A total of 1,428 public big data entries from January 2013 to December 2019 were collected. Disease data and basic climate/air pollutant concentration records were collected from nationally provided big data. Meteorological factors affecting eye diseases were identified using multiple linear regression and machine learning analysis methods such as extreme gradient boosting (XGBoost), decision tree, and random forest. The prediction model with the best performance was XGBoost (1.180), followed by multiple regression (1.195), random forest (1.206), and decision tree (1.544) when using root mean square error (RMSE) values. With the XGBoost model, province was the most important variable (0.352), followed by month (0.289) and carbon monoxide exposure (0.133). Other air pollutants including sulfur dioxide, PM₁₀, nitrogen dioxides, and ozone showed low associations with conjunctivitis. We identified factors associated with conjunctivitis using traditional multiple regression analysis and machine learning techniques. Regional factors were important for the prevalence of conjunctivitis as well as the atmosphere and air quality factors.

The Protective Effects of KAT5 Inhibition on Ocular Inflammation by Mediating the PI3K/AKT Pathway in a Murine Model of Allergic Conjunctivitis

Purpose

We aimed to explore the effect of lysine acetyltransferase KAT5 on allergic conjunctivitis (AC).

Methods

The effect of KAT5 on inflammatory response during AC progression was analyzed in the experimental allergic conjunctivitis (EAC) mouse model.

Results

The clinical score, permeability, total IgE, ovalbumin (OVA)-specific IgE, and IgG1/IgG2a were induced in the EAC mice, in which the overexpression of KAT5 could further enhance but KAT5 inhibitor NU9056 reduce the phenotypes. The eosinophilic infiltration was induced in EAC mice, in which the overexpression of KAT5 was able to further promote but NU9056 attenuate the phenotype. The expression of Eotaxin and RANTES and the inflammatory factors were upregulated in EAC mice and KAT5 overexpression increased, but NU9056 decreased the expression in the model. Significantly, the CD11c+ dendritic cells and CD4+ T cells infiltration in the conjunctiva was enhanced in EAC mice, whereas KAT5 overexpression induced but NU9056 suppressed the effect in the model. Mechanically, the phosphorylation of PI3K and Akt and the levels of histone H3 lysine 27 acetylation (H3K27ac) were enhanced in EAC mice, whereas the overexpression of KAT5 promoted and NU9056 repressed the phenotype in the mice. The enrichment of KAT5 and H3K27ac on PI3K promoter was increased in EAC mice, and the overexpression of KAT5 further enhanced the enrichment in the mice. Significantly, we observed similar results in the KAT5 knockout mice as well. Moreover, PI3K/AKT signaling inhibitor LY294002 reversed KAT5 overexpression-mediated phenotypes and inflammatory response after induction AC in vivo.

Conclusions

Therefore we concluded that KAT5 inhibition protected against ocular inflammation by mediating the PI3K/AKT pathway in EAC mouse model.

Synchronous Fluorescence as a Green and Selective Method for the Simultaneous Determination of Cetirizine and Azelastine in Aqueous Humor

A green, simple, quick and economical method is implemented for the first time for the simultaneous estimation of cetirizine (CTZ) and azelastine (AZE) as co-administered eye drops. The method relies on synchronous spectrofluorimetry with ∆λ = 60 nm. Cetirizine can be estimated at 231 nm and AZE can be measured at 294 nm, each at the other’s zero crossing point. All factors affecting the method were studied and properly optimized. Good correlation was obtained in the range of 0.1–2 µg mL⁻¹ for both drugs. The limits of detection were 0.014 and 0.010 µg mL⁻¹ and limits of quantitation were 0.043 and 0.029 µg mL⁻¹ for CTZ and AZE, respectively. Moreover, ICH guidelines were carried out to validate the adopted method. The method was suitable for the analysis of CTZ and AZE in synthetic mixtures, eye drops and aqueous humor. The mean percentage of recoveries of CTZ and AZE in spiked aqueous humor were 99.83 and 99.37, respectively. Furthermore, Green Analytical Procedure Index (GAPI) and analytical Eco-scale approaches were used to evaluate the greenness of the suggested method.

Role of Damage-Associated Molecular Patterns (DAMPs/Alarmins) in Severe Ocular Allergic Diseases

Severe ocular allergic diseases, such as atopic keratoconjunctivitis and vernal keratoconjunctivitis, cause severe allergic inflammation in the conjunctiva and corneal epithelial damage, resulting in visual disturbances. The involvement of damage (danger)-associated molecular patterns (DAMPs/alarmins) in the pathogenesis of these diseases has been recognized. Alarmins released from damaged corneal epithelial cells or eosinophils play a critical role in the induction of corneal lesions, vicious loop of corneal injury, and exacerbation of conjunctival allergic inflammation. Alarmins in the conjunctiva also play an essential role in the development of both allergic inflammation, based on the acquired immune system, and type 2 inflammation by innate immune responses in the ocular surface. Therefore, alarmins may be a potentially important therapeutic target in severe refractory ocular allergic diseases.

Thermo-sensitivity and erosion of chitosan crosslinked poly[N-isopropylacrylamide-co-(acrylic acid)-co-(methyl methacrylate)] hydrogels for application to the inferior fornix

Thermo-gels based on chitosan crosslinked poly(N-isopropylacrylamide) were developed as alternatives to conventional eye drops for the sustained release of ketotifen fumarate in the treatment of allergic conjunctivitis. The thermo-gelling properties of the base polymer were altered prior to crosslinking with chitosan by incorporation of the hydrophilic and hydrophobic comonomers acrylic acid and methyl methacrylate respectively. Varying amounts of chitosan were incorporated by ionic interaction to produce polyelectrolyte complexes or by carbodiimide chemistry to produce covalently crosslinked networks. The lower critical solution temperature of all the chitosan crosslinked thermo-gels produced was below the surface temperature of the eye. All the chitosan crosslinked thermo-gels were found to have greater than 80% equilibrium water contents following gelation. The method and amount of chitosan incorporation allowed for tailor-ability of material rheologic properties, with full degradation occurring over a one-to-four-day period, and tailorable rates of release of 40-60% of the loaded allergy medication ketotifen fumarate. The chitosan crosslinked thermo-gels were demonstrated to be nontoxic both in vitro and in vivo. It was demonstrated that the synthesized materials could be applied to the inferior fornix of eye, sustaining a multiple day release of ketotifen fumarate, as an alternative to conventional eyedrops. STATEMENT OF SIGNIFICANCE: Topical eyedrops are the main treatment modality for anterior ocular conditions. However, due to the natural clearance mechanisms of the eye, topical eyedrops are well established to be largely ineffective as a method of drug delivery. Herein, we investigate a method of altering thermo-gel properties of an n-isopropylacrylamide based polymer to enable the incorporation of greater amounts of chitosan by different methods of crosslinking. By controlling the synthesis parameters, final material properties can be tailored to impart ideal spreading, retention on the eye, and the rate of degradation and drug release over several days. This work also focuses on studying the rheological properties of the chitosan crosslinked thermo-gels which has not been investigated previously.

Knowledge and awareness of ocular allergy among Jeddah population

Background:

Ocular allergy is one of the common conditions that affects patients from different age groups. Public awareness about the disease is crucial for reducing the incidence of ocular allergy.

Aim:

The present study aims to evaluate the knowledge level of the general population in Jeddah, Saudi Arabia toward ocular allergy.

Methodology:

This is a cross-sectional study that included the distribution of an online survey to the public living in Jeddah. The survey included questions to identify common demographics, knowledge, and awareness about ocular allergy signs and symptoms, prevention and treatment, and sources of information. Statistical analysis included descriptive and comparative analysis using Chi-square test and one-way ANOVA test. SPSS version 26 was used for data analysis.

Results:

In total, 1207 responded to this survey and were included in the analysis. Among them, 71% were females, 36.8% were in the age group of 15–25 years, 74.9% had a bachelor’s degree, 60.4% were non-medical specialists, 13.2% were from the faculty of medicine. More than half of the participants were aware that ocular allergy affects millions of people globally every year. It is one of the most common eye conditions, itching is the primary source of discomfort, 15%–20% of the world population have ocular allergy, the disease causes discomfort and pain within the eye caused by frequent rubbing of the eye, and that symptoms of ocular allergy include redness, itching, tearing, discharge, blurred vision, and photophobia. Further, 64.9% thought that avoiding the source of triggers can help prevent ocular allergy. Social media was the most common source of information among 19.3%. The average score was 15.6 ± 6.1 out of 27 points; 42.6% of the responders had fair knowledge (50%–75%) about ocular allergy. The age group of 15–25 years (P < 0.001), bachelor’s degree holders (P = 0.013), and individuals with a medical background (P = 0.003) were associated with significantly higher mean scores. Males (P = 0.003), age group of 15–25 years (P = 0.024), individuals with a medical background (P < 0.001) had significantly good knowledge about ocular allergy.

Conclusion:

The knowledge level of the general population about ocular allergy in Jeddah, Saudi Arabia is fair and requires improvement.

Air pollution and meteorological conditions significantly contribute to the worsening of allergic conjunctivitis: a regional 20-city, 5-year study in Northeast China

This study is the first to explore the potential associations among allergic conjunctivitis (AC), air pollution, and meteorological conditions in Northeast China. Data of meteorology, ambient atmospheric pollutants, and the incidence of allergic conjunctivitis (IAC) in prefecture-level cities between the years 2014 and 2018 are analyzed. The results show an increasing trend in the AC of average growth rate per annum 7.6%, with the highest incidence in the provincial capitals. The IAC is positively correlated with atmospheric pollutants (i.e., PM_2.5, PM₁₀, CO, SO₂, NO₂, and O₃) and meteorological factors (i.e., air temperature and wind speed), but negatively correlated with relative humidity. These results suggest that the IAC is directly proportional to pollution level and climatic conditions, and also the precedence of air pollution. We have further obtained the threshold values of atmospheric pollutants concentration and meteorological factors, a turning point above which more AC may be induced. Compared with the air quality standard advised by China and the World Health Organization (WHO), both thresholds of PM₁₀ (70 μg m^-3) and PM_2.5 (45 μg m^-3) are higher than current standards and pose a less environmental risk for the IAC. SO₂ threshold (23 μg m^-3) is comparable to the WHO standard and significantly lower than that of China's, indicating greater environmental risks in China. Both thresholds of NO₂ (27 μg m^-3) and O₃ (88 μg m^-3) are below current standards, indicating that they are major environmental risk factors for the IAC. Our findings highlight the importance of atmospheric environmental protection and reference for health-based amendment.

Impact of Environmental Factors on the Prevalence Changes of Allergic Diseases in Elementary School Students in Ulsan, Korea: A Longitudinal Study

We examined the effect of long-term changes in environmental factors on the prevalence of allergic diseases in elementary school students in Ulsan, Korea. This longitudinal study was conducted among 390 students who were enrolled from three elementary schools in Ulsan in both the first (2009-2010) and second survey (2013-2014). The International Study of Asthma and Allergies in Childhood questionnaire was used to determine the prevalence of allergic diseases and hazardous environmental factors. Generalized estimating equations (GEE) were used to investigate the impact of environmental factors on the change in the prevalence of allergic diseases. The survey revealed that an increased risk of allergic rhinitis was associated with exposure to secondhand smoke, the remodeling of a room, the replacement of wallpaper or flooring, the use of a humidifier, and irritation symptoms of air pollution. Atopic dermatitis was associated with the relocation to or repairs of a new house, and allergic conjunctivitis was associated with low levels of weekly physical activity, the use of insecticides, and irritation symptoms of air pollution. The results indicate that (1) allergic rhinitis and atopic dermatitis are associated with indoor pollution, (2) allergic conjunctivitis is associated with exposure to indoor chemical compounds and low levels of weekly physical activity. This study suggested that the proper evaluation and decrease in the number of environmental risk factors could effectively manage allergic diseases.

Nanotechnology for the Treatment of Allergic Conjunctival Diseases

Allergic conjunctivitis is one of the most common external eye diseases and the prevalence has been increasing. The mainstay of treatment is topical eye drops. However, low bioavailability, low ocular drug penetration, transient resident time on the ocular surface due to tear turnover, frequent topical applications and dependence on patient compliance, are the main drawbacks associated with topical administration. Nanotechnology-based medicine has emerged to circumvent these limitations, by encapsulating the drugs and preventing them from degradation and therefore providing sustained and controlled release. Using a nanotechnology-based approach to load the drug is particularly useful for the delivery of hydrophobic drugs such as immunomodulatory agents, which are commonly used in allergic conjunctival diseases. In this review, different nanotechnology-based drug delivery systems, including nanoemulsions, liposomes, nanomicelles, nanosuspension, polymeric and lipid nanoparticles, and their potential ophthalmic applications, as well as advantages and disadvantages, are discussed. We also summarize the results of present studies on the loading of immunomodulators or nonsteroidal anti-inflammatory drugs to nano-scaled drug delivery systems. For future potential clinical use, research should focus on the optimization of drug delivery designs that provide adequate and effective doses with safe and satisfactory pharmacokinetic and pharmaco-toxic profiles.