Ocular Allergy Overview

Advances in Simple and Chiral-HPLC Methods for Antiallergic Drugs and Chiral Recognition Mechanism

Among many diseases, allergy appears to be a serious problem for human beings. Various forms of allergic disorders make people tense, leading to some other health issues. Many medications, including nonracemic and racemic ones, are used to treat this problem. It is important to have exact analysis strategies just to see any medication side effects, plasma profiles, and working efficiency. Therefore, efforts are made to review simple and chiral HPLC methods for antiallergic drugs; HPLC is the best analytical technique. The highlights in this article include the world scenario, causes of allergy, the effect of allergy on the economy, the mechanism of allergy in humans, classes of antiallergic drugs, simple drugs, chiral drugs, analysis by HPLC, and the chiral recognition mechanism. Moreover, attempts are also made to highlight the management of allergies and future perspectives.

Drug Delivery for Ocular Allergy: Current Formulation Design Strategies and Future Perspectives

The incidences of ocular allergy have been growing with the increase in pollution. Because of challenges in new drug development, there have been efforts to maximize the efficacy of existing drugs through drug delivery approaches. The effectiveness of drugs in ophthalmic conditions is primarily determined by permeability across the barrier, corneal retention, and sustained release. Thus, there have been widespread efforts to optimize these parameters to enhance efficacy through novel formulations. This review aims to analyze the approaches to drug delivery systems to encourage further research to optimize effectiveness. With this objective, research on drug delivery aspects of anti-allergy therapeutics was included and analyzed based on formulation/drug delivery technique, Food and Drug Administration approval limits, residence time, compatibility, pre-clinical efficacy, and potential for translational application. Conventional eye drops have concerns such as poor residence time and ocular bioavailability. The novel formulations have the potential to improve residence and bioavailability. However, the use of preservatives and the lack of regulatory approval for polymers limit the translational application. The review may assist readers in identifying novel drug delivery strategies and their limitations for the development of effective ophthalmic formulations for the treatment of ocular allergy.

Effectiveness of hyaluronic acid and arnica extract ophthalmic solution in reducing dry eye symptoms in pediatric population

AIM

to assess the effectiveness of a new combination of topical solution with Hyaluronic Acid 0.2% and arnica extract 0.1% in reducing dry eye symptoms in a population of pediatric patients.

METHODS

52 pediatric patients (aged 9 to 14 years) with signs and symptoms of dry eyes and allergic conjunctivitis were included in the study. Twenty-six patients were assigned to the Hyaluronic Acid 0.2%/ Arnica extract 0.1% group (Study Group) while 26 patients to the Hyaluronic Acid 0.2% group (Control Group). Clinical signs and symptoms were assessed at baseline and at week 4. The assessment plan included: slit-lamp examination, tear film break up time (TBUT), Schirmer's test and conjunctival hyperemia score. Ocular surface disease index (OSDI) score was used to evaluate subjective symptoms of dry eye disease.

RESULTS

Both treatment groups showed improvements in the estimated clinical parameters after treatment. OSDI score was significantly lower in both treatment groups (Study group p = 0.02; Control group p = 0.04) at the end of the follow up period. Improvements in TBUT, Schirmer's test results and conjunctival hyperemia were statistically significant only in the Study group (p = 0.021; p = 0.03; p < 0.01 respectively).

CONCLUSIONS

Preliminary findings suggest that combined topical Hyaluronic Acid 0.2% and arnica extract 0.1% can be effective in reducing symptoms and signs of dry eye disease in children.

A comprehensive summary of disease variants implicated in metal allergy

Allergic disease represents one of the most prominent global public health crises of the 21^st century. Although many different substances are known to produce hypersensitivity responses, metals constitute one of the major classes of allergens responsible for a disproportionately large segment of the total burden of disease associated with allergy. Some of the most prevalent forms of metal allergy - including allergic contact dermatitis - are well-recognized; however, to our knowledge, a comprehensive review of the many unique disease variants implicated in human cases of metal allergy is not available within the current scientific literature. Consequently, the main goal in composing this review was to (1) generate an up-to-date reference document containing this information to assist in the efforts of lab researchers, clinicians, regulatory toxicologists, industrial hygienists, and other scientists concerned with metal allergy and (2) identify knowledge gaps related to disease. Accordingly, an extensive review of the scientific literature was performed - from which, hundreds of publications describing cases of metal-specific allergic responses in human patients were identified, collected, and analyzed. The information obtained from these articles was then used to compile an exhaustive list of distinctive dermal/ocular, respiratory, gastrointestinal, and systemic hypersensitivity responses associated with metal allergy. Each of these disease variants is discussed briefly within this review, wherein specific metals implicated in each response type are identified, underlying immunological mechanisms are summarized, and major clinical presentations of each reaction are described.Abbreviations: ACD: allergic contact dermatitis, AHR: airway hyperreactivity, ASIA: autoimmune/ autoinflammatory syndrome induced by adjuvants, BAL: bronchoalveolar lavage, CBD: chronic beryllium disease, CTCL: cutaneous T-cell lymphoma, CTL: cytotoxic T-Lymphocyte, DRESS: drug reaction with eosinophilia and systemic symptoms, GERD: gastro-esophageal reflux disease, GI: gastrointestinal, GIP: giant cell interstitial pneumonia, GM-CSF: granulocyte macrophage-colony stimulating factor, HMLD: hard metal lung disease, HMW: high molecular weight, IBS: irritable bowel syndrome, Ig: immunoglobulin, IL: interleukin, LMW: low molecular weight, PAP: pulmonary alveolar proteinosis, PPE: personal protective equipment, PRR: pathogen recognition receptor, SLE: systemic lupus erythematosus, SNAS: systemic nickel allergy syndrome, Th: helper T-cell, UC: ulcerative colitis, UV: ultraviolet.

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.

Therapeutic Targets in Allergic Conjunctivitis

Allergic conjunctivitis (AC) is a common condition resulting from exposure to allergens such as pollen, animal dander, or mold. It is typically mediated by allergen-induced crosslinking of immunoglobulin E attached to receptors on primed conjunctival mast cells, which results in mast cell degranulation and histamine release, as well as the release of lipid mediators, cytokines, and chemokines. The clinical result is conjunctival hyperemia, tearing, intense itching, and chemosis. Refractory and chronic cases can result in ocular surface complications that may be vision threatening. Patients who experience even mild forms of this disease report an impact on their quality of life. Current treatment options range from non-pharmacologic therapies to ocular and systemic options. However, to adequately control AC, the use of multiple agents is often required. As such, a precise understanding of the immune mechanisms responsible for this ocular surface inflammation is needed to support ongoing research for potential therapeutic targets such as chemokine receptors, cytokine receptors, non-receptor tyrosine kinases, and integrins. This review utilized several published articles regarding the current therapeutic options to treat AC, as well as the pathological and immune mechanisms relevant to AC. This review will also focus on cellular and molecular targets in AC, with particular emphasis on potential therapeutic agents that can attenuate the pathology and immune mechanisms driven by cells, receptors, and molecules that participate in the immunopathogenesis and immunopathology of AC.

Prevalence of adenoviruses as ocular disease causatives in Saudi Arabia

Although Human Adenoviruses outbreaks are rare, there still could be a potential chance for those viruses to mutate and spread quickly in human populations with severe public health and socioeconomic consequences. Outbreaks often spread fairly quickly with considerable morbidity/mortality. Saudi Arabia's geopolitical and religious significance bring with it, millions of pilgrims, and tourists yearly. This presents a significant potential for HAdVs epidemics. This review shows that even with the mushrooming serotypes and genotypes, the scholarly knowledge on the nature, structure, transmission, and management of HAdVs is already well-established. Significant research is ongoing on pharmacological interventions, which, presently remain speculative and lacking in effectiveness. This review similarly uncovers a shortage of literature, both recent and dated, on epidemic keratoconjunctivitis in either Saudi Arabia or the Middle East.

The Role of Temperature Change, Ambient Temperature, and Relative Humidity in Allergic Conjunctivitis in a US Veteran Population

PURPOSE

Studies have implicated temperature and humidity in the pathogenesis of allergic conjunctivitis (AC), as these conditions facilitate air particulate and aeroallergen dispersion and tear film instability. Research also suggests that variation in temperature is associated with risk of asthma, but similar data are limited for AC. This study examined associations between several meteorologic conditions, including temperature variation, and AC visit risk.

DESIGN

Retrospective, case-crossover study.

METHODS

Data on individuals diagnosed with AC (via International Classification of Diseases-Ninth Edition [ICD-9]) at a Veterans Affairs clinic from January 2010-December 2013 was extracted. Local climate data were obtained from the National Climactic Data Center. Utilizing a case-crossover design, all cases were assigned a random control date 90-250 days prior to diagnosis. Daily time-lagged exposures were computed for 30-day lags. The associations between temperature, temperature variation (standard deviation [SD] of temperature), relative humidity (RH), and temperature-RH interaction with visit risk were examined via multivariate logistic regression models both at the national level and across domestic climate regions.

RESULTS

Overall, 74,951 subjects made 116,162 visits for AC. Prevalence was highest in spring (>10% April-May) in the Northeast (NE) and Southeast (SE) (>15%), and lowest in winter (<6.1% December-February) in the Pacific Northwest (PNW) (<5%). AC visit risk was positively associated with temperature (OR 1.028, P < .001), SD of temperature (OR 1.054, P < .01), and temperature-RH interaction (OR 1.0003, P < .01), whereas it was negatively associated with RH (OR 0.998, P < .001). Regionally, the PNW, NE, and Lower Midwest (LMW) accounted for the strongest associations.

CONCLUSION

Temperature, temperature variation, and RH associated with AC visit risk. Observed associations were strongest in northern regions, like the PNW.

Knowledge and awareness of nasal allergy among patients in a developing country

Background:

Nasal allergy is a common public health disorder seen in clinical practice worldwide. This disorder affected activities such as sleep, education, trading, economy, and social life. This study aimed at determining the level of knowledge and awareness of nasal allergy among patients seen in the otorhinolaryngology clinical practice of a developing country.

Methods and Materials:

This was a descriptive cross-sectional study, which was carried out among patients seen in Ekiti state university teaching hospital, Nigeria. Each patient completed a pretested interviewer assisted questionnaire on socio-demographic features, awareness, and knowledge on nasal allergy. Data obtained were documented, collated, and analyzed by SPSS version 18.0.

Results:

There were 16.4% patient's awareness and knowledge on nasal allergy, and 10.6% had allergic rhinitis. The patients included 59.2% males and male to female ratio was 1.5:1.Most common sources of information on nasal allergy were from ear, nose, and throat specialist/other doctors in 62.6%. Other sources were friends/relatives and media/Internet in 28.5% and 9.0%, respectively. Knowledge and awareness on if the nasal allergy was common in Nigeria and worldwide among the patients were 26.6% and 24.9%, respectively. However, 56.7% patients were aware that nasal allergy were commonly seen and diagnosed in the hospital.On the basis of knowledge and awareness of etiology of nasal allergy, majority 55.2% believed micro-organisms caused nasal-allergy. Minority 40.4% agreed nasal allergy was caused by parents genetic transmission from parents to offspring.On the awareness and knowledge of nasal allergy and its manifestations, the most common symptoms was 63.4% itching ear, throat, and eyes others were 63.2% catarrh and 56.3% bout of sneezing. There were 64.6% patients awareness of nasal allergy causes impairing concentration. However, 68.2% believed nasal allergy were curable diseases. On the awareness and knowledge, treatment was 52.7% prayer/spiritual intervention, 34.3% herbs, and 57.1% over-the-counter medication. However, 45.4% were aware and knowledgeable on the significance of avoidance of allergens.

Conclusion:

The level of awareness and knowledge on nasal allergy low with high levels of prevalence. Patients awareness and knowledge on etiology, clinical manifestations, effects, and management of nasal allergy is low.

Density and Morphology of Corneal Epithelial Dendritic Cells are Different in Allergy

Purpose: The role of corneal epithelial dendritic cells (CEDC), a subtype of antigen presenting cells, in ocular allergy remains largely unknown. This cross-sectional study evaluated the density and morphology of CEDC in participants diagnosed with systemic allergy, to increase our understanding of the role of CEDC in ocular inflammation associated with systemic allergy.Materials and methods: A convenience sample of 50 participants was categorised into allergic and non-allergic groups (31 allergic and 19 non-allergic) based on the results of skin prick test (SPT). Ocular allergy symptoms, clinical ocular surface signs and serum IgE were assessed. In vivo confocal microscopy was performed on the right eye only. The number of CEDC in a 1mm² region at both the central and mid-peripheral cornea was manually counted. CEDC morphology was graded on a 1 to 3 scale.Results: Ocular surface symptoms, signs (other than eyelid oedema), and serum IgE were significantly higher in the allergic (SPT+) group. CEDC density at the mid-peripheral cornea was significantly lower in the allergic group (p = .003). CEDC morphology grades were significantly higher in allergic participants in the central cornea (p = .02), with the highest grade morphology observed only in allergic participants. No associations were evident between CEDC density or morphology and ocular signs, symptoms or serum IgE.Conclusions: The study showed reduced CEDC density and cells with longer dendrites in allergic participants. The more mature CEDC morphology in the allergic group is suggestive of an inflammatory or immune response.

Sublingual immunotherapy for pediatric allergic conjunctivitis: a meta-analysis of randomized controlled trials

BACKGROUND

Allergic conjunctivitis (AC) is a common chronic condition, especially in children. Ocular symptoms are often overlooked during treatment of allergic rhinoconjunctivitis (ARC). Pediatric ARC can be effectively treated using sublingual immunotherapy (SLIT), which is a guideline-recommended safe treatment approach. However, the therapeutic efficacy of SLIT in terms of ameliorating eye symptoms has not been effectively evaluated.

METHODS

We performed a meta-analysis of randomized controlled trials (RCTs) evaluating the use of SLIT for infants, children, and adolescents (aged from 3 to 18 years) with AC or ARC. We searched the Cochrane Library database, EMBASE, and Medline from November 1990 to 2017 to find papers dealing with the effects of SLIT on pediatric AC or ARC. We used standardized mean differences (SMDs) to assess therapeutic effects, employing a random effects model. Subgroup and sensitivity analyses were also conducted. The I² metric was used to evaluate heterogeneity.

RESULTS

In total, 13 clinical RCTs were included in our meta-analysis. SLIT reduced ocular symptoms to a level below that of controls (SMD = -0.21; 95% confidence interval [CI], -0.41 to -0.01; p = 0.04; I² = 55%). Notably, on subgroup analysis, SLIT clearly reduced pollen-induced pediatric AC (SMD = -0.36; 95% CI, -0.53 to -0.19; p < 0.0001; I² = 25%) but not mite-induced AC (SMD = 0.20; 95% CI, -0.20 to 0.60; p = 0.34; I² = 46%).

CONCLUSION

SLIT relieved ocular symptoms in children with ARC or AC. To confirm these results, future meta-analyses should evaluate high-quality, large-scale population-based trials.

MiR-146a overexpression effectively improves experimental allergic conjunctivitis through regulating CD4+CD25-T cells

OBJECTIVE

To study the mechanism of miR-146a in the regulation of allergic conjunctivitis (AC) through CD4⁺CD25^-T cells.

METHODS

BALB/c mice were sensitized with ragweed pollen (RW) and alum, and then challenged with RW. Eosinophil infiltration was determined using Giemsa assay. ELISA assay was performed to examine the level of antigen-specific IgE in the serum and cytokine levels in splenocytes. The expression of miR-146a was measured by qRT-PCR. Flow cytometric analysis was used to analyze the percentage of CD4⁺CD25^-T cells and Tregs.

RESULTS

In this study, we found that miR-146a overexpression could effectively improve the symptoms of AC in mouse models. Moreover, in vitro experiments, the proliferation of splenocytes was controlled and the expression of IL-5 and IL-13 was also decreased after transfected with miR-146a mimic. In addition, the inhibitory effect of Tregs on Tcons was affected by the change of miR-146a content in Tcons and had a positive correlation effect. When the content of miR-146a in Tregs changed, the inhibition was not affected. In addition, when inhibited miR-146a, NF-κB signaling pathway was activated, and the expression of IL-5 and IL-13 in Tcons increased. While after added Bay (NF-κB blocker), the NF-κB activity was decreased, and the expression of IL-5 and IL-13 in Tcons also reduced.

CONCLUSION

MiR-146a decreased in Tcons was contributed to the development of AC through regulating the inhibitory effect of Tregs on Tcons and NF-κB signaling pathway.

Increased red cell distribution width levels in children with seasonal allergic conjunctivitis

PURPOSE

Seasonal allergic conjunctivitis (SAC) is an inflammatory disease of the conjunctiva. Red cell distribution width (RDW) is a widely accepted inflammatory marker. We aimed to investigate whether RDW level is associated with the development of SAC in pediatric population.

METHODS

The present study consisted of 90 subjects (45 children with SAC and 45 age- and sex-matched healthy children). The demographic findings, complete blood count parameters including RDW and laboratory parameters, were evaluated.

RESULTS

The mean RDW levels were significantly higher in children with SAC compared to the control group (14.02 ± 0.82 vs. 13.26 ± 0.64%, respectively, p < 0.001). In receiver operating characteristic analysis, the area under the curve for RDW for predicting SAC was 0.786, and a RDW value of 13.45 or higher predicted SAC with a sensitivity of 75.6% and specificity of 65%.

CONCLUSION

Our study suggests that elevated RDW levels are significantly associated with SAC in pediatric population, which may imply a possible role of increased inflammatory status and oxidative stress in the pathogenesis of SAC.

Efficacy of olopatadine hydrochloride 0.1%, emedastine difumarate 0.05%, and loteprednol etabonate 0.5% for Chinese children with seasonal allergic conjunctivitis: a randomized vehicle-controlled study

Background

Allergic conjunctivitis (AC) is a disease of various agents that affects the physical and mental health of children. Although the most effective therapy has not been found so far, it is essential to explore the considerable therapeutic method. We compared the clinical efficacy of olopatadine, emedastine, loteprednol etabonate (LE), and vehicle for treating seasonal allergic conjunctivitis (SAC) in Chinese children.

Methods

Eighty cases of 160 eyes aged from 5 to 10 years with SAC were available and those subjects were randomly distributed into 4 groups. Both their eyes received olopatadine hydrochloride 0.1% twice a day, emedastine difumarate 0.05% twice a day, or LE 0.5% 4 times a day, respectively, whereas those of the control group received artificial tears (AT) 0.5% 3 times a day. This study was conducted successfully and the observations were collected before treatment and on day 8 (±1 day) and day 15 (±2 days) afterward. The principal measurement of efficacy was focused on the signs and symptoms of the subjects, evaluated before and after treatment, in addition to visual acuity (VA) and fundus oculi.

Results

On day 8 (±1 day) and day 15 (±2 days), all the antiallergic agents were found to be more effective than vehicle (p < 0.05) in terms of all the symptoms and signs. However, there was no statistical significance (p ≥ 0.05) shown among the treatment groups. There were no evident changes in VA and no clinically significant changes were observed in fundus oculi.

Conclusion

After the treatment, the efficacy presented a similar distribution among the trial groups.

Knowledge and awareness of ocular allergy among undergraduate students of public universities in Ghana

BACKGROUND

Ocular allergy is a growing public health problem that greatly impacts the day-to-day life of sufferers and their families. Other aspects of their activities of daily living such as schooling, professional, and social life are affected hence an increased awareness and knowledge of ocular allergies, their detection and treatment is paramount. This study was to assess the level of knowledge and awareness of ocular allergy among undergraduate students of public universities in Ghana.

METHODS

A descriptive cross sectional survey was conducted among 1000 students from three selected public universities in Ghana. Each respondent completed a questionnaire that had questions concerning awareness and knowledge of ocular allergy.

RESULTS

Out of the 1000 students, 347 (34.7 %) were aware of ocular allergy. Of these 347 students, the level of knowledge of ocular allergy was generally low. Majority of the students had their source of information about ocular allergy from the media and the internet. There was statistical significant association among awareness of ocular allergy, sources of information and programme of study (p < 0.001).

CONCLUSION

Level of awareness among university students is generally low. Students' programmes of study influenced their knowledge of ocular allergy. Public health measures are recommended to help educate students on the prevention and control of ocular allergy as well as the complications associated with this condition.

Dry Eye Syndrome and Allergic Conjunctivitis in the Pediatric Population

Purpose:

To assess the comorbidity of dry eye syndrome (DES) and changes in corneal curvature in children with allergies.

Materials and Methods:

This prospective, comparative, and observational interventional study included 49 patients, who presented to the Ophthalmology Clinic of a State Hospital in Turkey. There were 25 patients with clinically diagnosed seasonal allergic conjunctivitis (AC) (with complaints of itching and papilla formation of conjunctiva; AC group) and 24 healthy children (control group). There with no significant differences in age between groups. Using the ocular surface disease index (OSDI) questionnaire, we performed tear film break-up time (BUT), central reflex tear meniscus height (TMH-R) measurement, Schirmer test on both groups and evaluated keratometry (K1, K2) and spherical equivalent (SE).

Results:

Patients ranged in age from 6 to 18 years (median age, 11.79 years; 46.9% male; 53.1% female). The papillary reaction was severe in 10% of patients with AC. The prevalence of dry eye in children with AC was 12%. There was no statistically significant difference between groups for K1, K2, and SE (P > 0.05, all comparisons). BUT was statistically different (P = 0.004) between groups, indicating that a higher OSDI the tear film BUT was lower (ρ = 0.567). Statistically, significant negative moderate correlations were found between papillary reaction and the Schirmer test, BUT, and TMH-R (ρ = 0.454, −0.412, −0.419, and P = 0.001, 0.003, 0.002, respectively)

Conclusions:

The evaluation of pediatric patients with AC requires further attention to ensure an adequate diagnosis of DES.

Effect of alcaftadine 0.25% on ocular itch associated with seasonal or perennial allergic conjunctivitis: a pooled analysis of two multicenter randomized clinical trials

PURPOSE

Seasonal and perennial allergic conjunctivitis represent the majority of cases of ocular allergy. This analysis was designed to evaluate the efficacy and safety of once-daily alcaftadine 0.25% in preventing ocular itching associated with seasonal or perennial allergic conjunctivitis.

SUBJECTS AND METHODS

Pooled data from two double-masked, multicenter, placebo-controlled studies using the conjunctival allergen challenge (CAC) model of allergic conjunctivitis were analyzed. Subjects randomized to receive treatment with alcaftadine 0.25% or placebo were challenged with seasonal (grass, ragweed, trees) or perennial (cat dander, cat hair, dog dander, dust mites, cockroach) allergens, 16 hours after treatment instillation. The primary efficacy measure was subject-evaluated mean ocular itching at 3 minutes post-CAC. Secondary measures included ocular itching at 5 and 7 minutes post-CAC. The proportion of subjects with minimal itch (itch score <1) and zero itch (itch score =0), and safety were also assessed.

RESULTS

A total of 189 subjects enrolled in the two studies were treated with alcaftadine or placebo. Overall, 129 subjects were challenged with seasonal allergens and 60 subjects were challenged with perennial allergens. Alcaftadine 0.25% achieved a statistically significant reduction in mean itch score at 3, 5, and 7 minutes post-CAC compared with placebo in subjects challenged with seasonal allergens (P<0.0001 at all time points) and those challenged with perennial allergens (P<0.0001 at all time points). A higher percentage of subjects treated with alcaftadine compared with placebo achieved minimal itch (P≤0.001 versus placebo at all time points) and zero itch (P<0.05 at all time points except 7 minutes for perennial) when challenged with either seasonal or perennial allergens. No treatment-related or serious adverse events were reported.

CONCLUSION

Once-daily alcaftadine 0.25% ophthalmic solution was well tolerated and demonstrated effective relief of ocular itching in subjects challenged with allergens classic for triggering either seasonal or perennial allergic conjunctivitis.

Central corneal thickness in patients with atopic keratoconjunctivitis

Background

The aim of this study was to evaluate central corneal thickness in patients with atopic keratoconjunctivitis.

Material/Methods

The study was conducted in the Atatürk University School of Medicine between April 2011 and June 2013. The study group included 60 eyes of 30 patients with atopic keratoconjunctivitis. Sixty eyes of 30 healthy individuals without any ophthalmic or systemic pathology were used as a control group. The central corneal thickness was measured with ultrasonic pachymetry.

Results

In each group, all subjects included in the study had a best corrected visual acuity (BCVA) of 20/25 or better. In the study group past medical histories revealed eczema in 19 patients, asthma in 16, and atopic dermatitis in 15. During clinical examination cicatricial conjunctivitis was noted in 5 patients, giant papillae in 4, symblepharon in 2, and entropion in 2. The mean central corneal thickness was 523.45±18.03 μm in the study group (mean age: 37.05±5.7 years) and 540.30±38.91 μm in the control group (mean age: 36.55±7.1 years), and the difference was statistically significant (p<0.001).

Conclusions

Evaluation of corneal thickness is important in situations such as corneal refractive surgery and contact lens use, and is an essential parameter in a wide range of ocular disorders, including glaucoma and keratoconus. Therefore, ophthalmologists should be aware of the low central corneal thickness in patients with atopic keratoconjunctivitis.

Allergic conjunctivitis: an update on diagnosis and management

PURPOSE OF REVIEW

The focus of this review is to provide a logical paradigm for the diagnosis and treatment of ocular allergies, with a focus on seasonal allergic conjunctivitis (SAC) and perennial allergic conjunctivitis (PAC).

RECENT FINDINGS

Several classes of topical medications are currently available for the management of ocular allergies, including: lubricating agents, vasoconstrictors, antihistamines, mast cell stabilizers, and topical corticosteroids.

SUMMARY

SAC and PAC make up the vast majority of ocular allergy cases. A proactive approach to these diseases, anticipating the regional spring and fall allergen spikes, is needed for optimally managing these disorders. A multifaceted treatment regimen comprising patient education, lifestyle modification, and topical medications (such as antihistamines and/or mast cell stabilizers and corticosteroids) may be required in order to manage ocular allergies effectively. The appropriate treatment paradigm is based on the severity of the patients' signs and symptoms. For moderate-to-severe cases, especially chronic vernal keratoconjunctivitis, atopic keratoconjunctivitis, and giant papillary conjunctivitis, comanagement with an ophthalmologist is recommended.

Cytokine profiles in tears accompanying the secondary conjunctival responses induced by nasal allergy

PURPOSE/AIM

Allergic conjunctivitis (AC) occurs either in a primary form, due to the allergic reaction localized in the conjunctivae or in a secondary form, induced by an allergic reaction initiated primarily in the nasal mucosa. The purpose of this study was to investigate the cytokine profiles in tears associated with the secondary conjunctival response (SCR) types.

MATERIALS AND METHODS

In 47 AC patients developing 16 immediate (SICR; p < 0.01), 20 late (SLCR; p < 0.001) and 11 delayed (SDYCR; p < 0.05) responses to nasal provocation tests (NPTs) with allergens, the NPTs were repeated and combined with recording of cytokine concentrations in the tears.

RESULTS

The SCRs were associated with significant concentration changes of particular cytokines in tears (p < 0.05) as follows: (1): SICRs: interleukin (IL)-3, IL-4, IL-10 and granulocyte macrophage colony-stimulating factor (GM-CSF); (2) SLCRs: IL-3, IL-4, IL-5, IL-8, IL-10, IL-12p40, GM-CSF and granulocyte colony-stimulating factor (G-CSF); and (3) SDYCRs: IL-2, IL-8, IL-10, interferon gamma, G-CSF and tumor necrosis factor alpha. No significant cytokine changes were recorded in tears during the phosphate-buffered saline controls or negative SCRs.

CONCLUSIONS

Different cytokine profiles in the tears accompanying the immediate, late and delayed types of SCR, induced by nasal allergy, would indicate involvement of different hypersensitivity mechanisms in the particular SCR types. The low cytokine concentrations in tears recorded during the SCRs may suggest their origin from the nasal mucosa. These results emphasize the diagnostic value of NPTs with allergens combined with monitoring of various ocular features in patients suffering from the secondary form of AC. These results may also have an impact on the therapeutical approach to this clinical entity.

Effectiveness of nonpharmacologic treatments for acute seasonal allergic conjunctivitis

OBJECTIVE

To investigate whether artificial tears and cold compress alone or in combination provide a treatment benefit and whether they were as effective as or could enhance topical antiallergic medication.

DESIGN

Randomized, masked clinical trial.

PARTICIPANTS

Eighteen subjects (mean age, 29.5±11.0 years) allergic to grass pollen.

INTERVENTION

Controlled exposure to grass pollen using an environmental chamber to stimulate an ocular allergic reaction followed by application of artificial tears (ATs), 5 minutes of cold compress (CC), ATs combined with CC, or no treatment applied at each separate visit in random order. A subset of 11 subjects also had epinastine hydrochloride (EH) applied alone and combined with CC in random order or instillation of a volume-matched saline control.

MAIN OUTCOME MEASURES

Bulbar conjunctival hyperemia, ocular surface temperature, and ocular symptoms repeated before and every 10 minutes after treatment for 1 hour.

RESULTS

Bulbar conjunctival hyperemia and ocular symptoms decreased and temperature recovered to baseline faster with nonpharmaceutical treatments compared with no treatment (P <0.05). Artificial tears combined with CC reduced hyperemia more than other treatments (P <0.05). The treatment effect of EH was enhanced by combining it with a CC (P <0.001). Cold compress combined with ATs or EH lowered the antigen-raised ocular surface temperature to less than the pre-exposure baseline. Artificial tear instillation alone or CC combined with ATs or EH significantly reduced the temperature (P <0.05). Cold compress combined with ATs or EH had a similar cooling effect (P >0.05). At all measurement intervals, symptoms were reduced for both EH and EH combined with CC than CC or ATs alone or in combination (P <0.014).

CONCLUSIONS

After controlled exposure to grass pollen, CC and AT treatment showed a therapeutic effect on the signs and symptoms of allergic conjunctivitis. A CC enhanced the use of EH alone and was the only treatment to reduce symptoms to baseline within 1 hour of antigenic challenge. Signs of allergic conjunctivitis generally were reduced most by a combination of a CC in combination with ATs or EH.

Epidemiology of ocular allergy and co-morbidities in adolescents

OBJECTIVE

The prevalence of allergic conjunctivitis (AC) has not been established. Estimates suggest that ocular allergies affect 15% to 20% of the worldwide population, yet most epidemiological studies encompass nasal and ocular allergy symptoms and have not been specific to AC. The aim of this study was to verify the prevalence of ocular allergy symptoms, co-morbidities, and their impact on adolescents.

METHODS

Adolescents were selected from a sample of schools, and completed in classrooms a previously validated questionnaire on symptoms of AC. AC diagnosis was considered when more than three episodes of ocular itching were reported in the past 12 months. Related symptoms such as tearing, photophobia, foreign body sensation, impact on daily activities, and diagnosis of AC were analyzed.

RESULTS

Questionnaires were obtained from 3,120 adolescents (mean age 13.3±1.1 years). Ocular itching in the past 12 months occurred in 1,592 (51%). The most frequently associated symptom was tearing (74%), followed by photophobia (50.1%) and foreign body sensation (37.1%). The prevalence of AC was 20.7%, affecting more females than males (56.1% versus 45.9%; p= 0.01). The risks of an adolescent with ocular allergy to present asthma, rhinitis, and atopic eczema were (OR= 5.7; 95% CI: 4.5 to 7.1), (OR=3.6; 95% CI: 3.0 to 4.3), and (OR=2.6; 95% CI: 2.0 to 3.5), respectively. Severe interference in daily activities was reported by 30.5%.

CONCLUSIONS

Symptoms of ocular allergy are common, frequently associated to other allergic diseases, and impact the daily activities of adolescents.

Molecular immunology of allergic conjunctivitis

PURPOSE OF REVIEW

Successful treatment of allergic eye disease depends on understanding the pathophysiology of ocular allergy. Thus, in this review, recent experimental and clinical research that has provided significant information about the immunopathology of allergic eye disease will be discussed.

RECENT FINDINGS

Recently, role of various cells, cytokines and chemokines has been scrutinized in the immunopathogenesis of ocular allergy. In this respect, current research highlights contribution of special molecules and cells in the development and clinical features of immunoglobulin E (IgE) and T-cell-mediated eye allergies.

SUMMARY

Recent findings in molecular immunology of ocular allergy, which comprise complex inflammatory conditions of the conjunctiva, have enabled us to better understand the pathophysiology of these diseases and have aided in the potential development of new therapeutic agents.

Comparative efficacy of bepotastine besilate 1.5% ophthalmic solution versus olopatadine hydrochloride 0.2% ophthalmic solution evaluated by patient preference

BACKGROUND

The aim of this study was to compare patient-perceived relief of ocular itch, nasal symptoms, and eye drop comfort when allergic conjunctivitis was treated with bepotastine besilate 1.5% versus olopatadine hydrochloride 0.2%.

METHODS

This randomized, observer-masked, single-center, crossover study included 30 patients with ocular itching associated with allergic conjunctivitis accompanied by nasal symptoms. Patients were treated with bepotastine besilate 1.5% twice daily (7 am and 4 pm) or olopatadine hydrochloride 0.2% once daily (7 am) for 14 days. Following a 7-day washout period during which only preservative-free artificial tears were used twice daily, patients were crossed over to the alternative treatment for 14 days. Parameters evaluated by twice-daily patient diaries included each treatment's ability to relieve ocular itch, ability to relieve itchy/runny nose, ability to relieve ocular allergy symptoms, and eye drop comfort. At the conclusion of the study, patients were also asked to identify which agent provided better all-day relief of ocular itching, better all-day relief of itchy/runny nose, superior comfort, and for which treatment they would prefer a prescription.

RESULTS

According to the mean daily diary responses, bepotastine besilate 1.5% provided significantly better relief of evening ocular itch, relief of morning and evening itchy/runny nose, and relief of morning and evening ocular allergy symptoms. At study end, 63.3% and 66.7% of patients preferred bepotastine besilate 1.5% for all-day relief of ocular itching and all-day relief of itchy/runny nose, respectively. At study end, there was no significant difference in the number of patients preferring one treatment over the other for comfort. Overall, 66.7% of patients stated that they would prefer to treat their allergic conjunctivitis with bepotastine besilate 1.5% over olopatadine hydrochloride 0.2%.

CONCLUSION

Based on their evaluation of therapeutic performance, patients preferred bepotastine besilate 1.5% over olopatadine hydrochloride 0.2% by two-to-one for the treatment of allergic conjunctivitis.

Steroid-induced ocular hypertension in Asian children with severe vernal keratoconjunctivitis

Background

We describe clinical characteristics and risk factors for corticosteroid response in children with severe vernal keratoconjunctivitis (VKC).

Design

Retrospective, noncontrolled, comparative case series.

Participants

Patients from three tertiary centers in Singapore.

Methods

We reviewed patients with severe VKC (clinical grade > 2) who were on topical steroid therapy, with a minimum follow-up period of 1 year post-presentation. Logistic regression was used to determine risk factors for corticosteroid response.

Main outcome measure

Corticosteroid response was defined as intraocular pressure (IOP) >21 mmHg (three consecutive readings), or a rise of more than 16 mmHg from baseline, after commencement of steroid therapy in the absence of other possible causes of raised IOP.

Results

Forty-one of 145 (28.3%) patients developed a corticosteroid response, of which eight (5.5%) progressed to glaucoma. The overall mean age of onset of VKC was 9.9 ± 4.4 years. Longer duration of corticosteroid use (OR, 5.06; 95% CI: 1.04–25.56; P = 0.45) and topical dexamethasone 0.01% (OR, 2.25; 95% CI: 1.99–5.08; P = 0.40) were associated with corticosteroid response. Mixed type of VKC (OR, 9.76; 95% CI: 3.55–26.77; P < 0.001), the presence of limbal neovascularization of ≥ three quadrants (OR, 6.33; 95% CI: 2.36–16.97; P < 0.001), and corneal involvement (OR, 3.51; 95% CI: 1.31–9.41; P = 0.012) were significant clinical risk factors after adjusting for potential confounders such as age, sex, ethnicity, duration, and type of corticosteroid used.

Conclusion

Children on long-term oral corticosteroids with severe, mixed-type VKC and corneal involvement are more likely to develop corticosteroid response, and may require early treatment to prevent progression to glaucoma.

Epidemiology of allergic conjunctivitis

PURPOSE OF REVIEW

To describe currently available epidemiological data on the prevalence of allergic conjunctivitis. Allergic conjunctivitis is often underdiagnosed and consequently undertreated except when it is severe and the chief complaint of a consultation in a specialty clinic. Use of healthcare resources and reduced quality of life of affected individuals justify studies on the prevalence of allergic conjunctivitis.

RECENT FINDINGS

The association of allergic nasal and ocular symptoms (rhinoconjunctivitis) is common. Most children with allergic conjunctivitis have allergic rhinitis. Older population studies estimate a prevalence of 15-20% of allergic conjunctivitis, but more recent studies implicate rates as high as 40%. Ocular symptoms are common and contribute to the burden of allergic rhinitis and lower quality of life. Ocular allergies rank a very close second and at times may overcome the primary complaints of nasal congestion in rhinoconjunctivitis patients.

SUMMARY

Little focus has been set on the impact of allergic conjunctivitis as comorbidity to asthma and rhinitis in atopic patients. Conjunctivitis symptoms are at least as severe as rhinitis symptoms in patients with 'hay fever' and some have even generated the term of conjunctivorhinitis stressing the ocular symptoms. Prevalence studies should be specifically addressed to ocular allergy symptoms.

A review of non-pharmacological and pharmacological management of seasonal and perennial allergic conjunctivitis

Allergic eye disease encompasses a group of hypersensitivity disorders which primarily affect the conjunctiva and its prevalence is increasing. It is estimated to affect 8% of patients attending optometric practice but is poorly managed and rarely involves ophthalmic assessment. Seasonal allergic conjunctivitis (SAC) is the most common form of allergic eye disease (90%), followed by perennial allergic conjunctivitis (PAC; 5%). Both are type 1 IgE mediated hypersensitivity reactions where mast cells play an important role in pathophysiology. The signs and symptoms are similar but SAC occurs periodically whereas PAC occurs year round. Despite being a relatively mild condition, the effects on the quality of life can be profound and therefore they demand attention. Primary management of SAC and PAC involves avoidance strategies depending on the responsible allergen(s) to prevent the hypersensitivity reaction. Cooled tear supplements and cold compresses may help bring relief. Pharmacological agents may become necessary as it is not possible to completely avoid the allergen(s). There are a wide range of anti-allergic medications available, such as mast cell stabilisers, antihistamines and dual-action agents. Severe cases refractory to conventional treatment require anti-inflammatories, immunomodulators or immunotherapy. Additional qualifications are required to gain access to these medications, but entry-level optometrists must offer advice and supportive therapy. Based on current evidence, the efficacy of anti-allergic medications appears equivocal so prescribing should relate to patient preference, dosing and cost. More studies with standardised methodologies are necessary elicit the most effective anti-allergic medications but those with dual-actions are likely to be first line agents.

The role of histamine in ocular allergy

Ocular allergy is a disorder affecting increasing numbers of individuals worldwide. Among the inflammatory mediators that contribute to ocular allergy, histamine is perhaps the best characterized. This monoamine is released by sensitized mast cells upon exposure to allergen and causes symptoms such as redness and tearing. Histamine may also recruit immune cells that can cause long-term damage to ocular surfaces. In this chapter we will discuss the known functions of histamine and histamine receptors in ocular allergy and will describe promising therapies targeting the histamine-signaling pathway.

Sublingual immunotherapy for treating allergic conjunctivitis

BACKGROUND

Allergic ocular symptoms, although frequently trivialised, are common and represent an important comorbidity of allergic rhinitis. Sublingual Immunotherapy (SLIT) is an effective and well-tolerated treatment for allergic rhinitis, but its effects on symptoms of ocular allergy have not been well established.

OBJECTIVES

To evaluate the efficacy of SLIT compared with placebo for reductions in ocular symptoms, topical ocular medication requirements and conjunctival immediate allergen sensitivity.

SEARCH STRATEGY

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2011, Issue 1), MEDLINE (January 1950 to January 2011), EMBASE (January 1980 to January 2011), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to January 2011), Web of Science (January 1970 to January 2011), Biosis Previews, (January 1979 to January 2011), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) (January 2011), ClinicalTrials.gov (www.clinicaltrials.gov) (January 2011), the Australian New Zealand Clinical Trials Registry (ANZCTR) (www.actr.org.au) (July 2010), SCOPUS (November 2008) and the UK Clinical Trials Gateway (January 2010). There were no language or date restrictions in the search for trials. All electronic databases except for SCOPUS, the UK Clinical Trials Gateway and ANZCTR were last searched on 19 January 2011.

SELECTION CRITERIA

Randomised controlled trials (RCTs), double-masked and placebo controlled, which evaluated the efficacy of SLIT in patients with symptoms of allergic rhinoconjunctivitis (ARC) or allergic conjunctivitis (AC).

DATA COLLECTION AND ANALYSIS

The primary outcome was the total ocular symptom scores. Secondary endpoints included individual ocular symptom scores (such as itchy eyes, red eyes, watery eyes, swollen eyes), ocular medication scores (eye drops) and conjunctival immediate allergen sensitivity (CIAS). Data were analysed and reported as standardised mean differences (SMDs) using Review Manager software.

MAIN RESULTS

Forty-two trials (n = 3958 total participants; n= 2011 SLIT and n = 1947 placebo) had available data to evaluate the efficacy of SLIT on AC and were included in the meta-analyses. Heterogeneity among studies (I(2) statistic) was around 50% or below for all endpoints. Sublingual immunotherapy induced a significant reduction in both total ocular symptom scores (SMD -0.41; 95% confidence interval (CI) -0.53 to -0.28; P < 0.00001; I(2) = 59%) and individual ocular symptom scores for red eyes (SMD -0.33; 95% CI -0.45 to -0.22; P < 0.00001; I(2) = 27%), itchy eyes (SMD -0.31; 95% CI -0.42 to -0.20; P < 0.00001; I(2) = 46%) and watery eyes (SMD -0.23; 95% CI -0.34 to -0.11; P < 0.0001; I(2) = 42%) compared to placebo. Those participants having active treatment showed an increase in the threshold dose for the conjunctival allergen provocation test (SMD 0.35; 95% CI 0.00 to 0.69; P = 0.05; I(2) = 43%). No significant reduction was observed in ocular eye drops use (SMD -0.10; 95% CI -0.22 to 0.03; P = 0.13; I(2) = 34%).

AUTHORS' CONCLUSIONS

Overall, SLIT is moderately effective in reducing total and individual ocular symptom scores in participants with ARC and AC. There were however some concerns about the overall quality of the evidence-base, this relating to inadequate descriptions of allocation concealment in some studies, statistical heterogeneity and the possibility of publication bias. There is a need for further large rigorously designed studies that study long-term effectiveness after discontinuation of treatment and establish the cost-effectiveness of SLIT.

Clinical trials in allergic conjunctivits: a systematic review

BACKGROUND

Ocular allergy represents one of the most common conditions encountered by allergists and ophthalmologists. However, there is wide variability of study designs in clinical trials of allergic conjunctivitis, which results in conflicting evidence on their optimal management. We conducted a systematic review of clinical trials to critically evaluate their quality and to highlight biases to be avoided in future clinical research in ocular allergy.

METHODS

Clinical trials in allergic conjunctivitis performed since 1965 were retrieved, and data on patients, interventions, comparison of interventions, and outcomes were extracted. Four authors independently assessed articles for inclusion in the systematic review and assessed trials' quality using the Jadad scale.

RESULTS

Three hundred and sixty-two trials were included in the study. Only a minority of trials fulfilled all the criteria of proper clinical trial design. In most of the studies, there was a very limited use of objective (quantifiable) parameters for both patients' selection and evaluation of drug efficacy and safety. Several outcomes of primary importance, such as disease relapses and recurrence rate, were omitted in clinical trials of allergic conjunctivitis.

CONCLUSIONS

Evidence coming out of clinical trials in ocular allergy is limited, and this affects the strength of recommendations to health care providers and policy makers for optimal management. Standardized diagnostic criteria for patient selection and quantifiable primary outcomes are recommended to improve the design of future clinical trials in allergic conjunctivitis.

Atopic dermatitis and keratoconjunctivitis

Atopic dermatitis, a chronic disease seen by allergist-immunologists, has both dermatologic and ocular manifestations. The ocular component is often disproportionately higher than the dermatologic disease. Even if skin abnormalities seem well controlled, these patients require ophthalmic evaluation. Atopic keratoconjunctivitis in atopic dermatitis patients is characterized by acute exacerbations and requires maintenance therapy for long-term control. Future studies will continue to emphasize the use of steroid-sparing, immunomodulating agents that have the potential to provide long-lasting anti-inflammatory control with a more favorable side-effect profile.

Prevalence and impact of ocular allergy in the population attending UK optometric practice

PURPOSE

To determine the prevalence of ocular allergy in patients attending optometric practices in the UK West Midlands and the impact this has on patients' daily lives.

METHOD

Patients attending 9 optometric practices in the West Midlands, UK, were surveyed about the occurrence of ocular allergy, the severity of the symptoms and their treatment. Patients self-reporting ocular allergy were invited to complete a more detailed questionnaire.

RESULTS

Of the 1904 consecutive patients assessed (mean age 47.7±23.2 years, 55% female), 13% reported an allergy, 8% an ocular allergy, rated as at least mild in 85% of cases. Medication was used by 77% of patients reporting ocular symptomology. Patients with ocular allergy (n=126) completed the detailed questionnaire. Seasonal symptoms occurred for 3.4±1.9 months of the year with a peak in June to July. The most common 'hayfever' type symptoms were itchy eyes and a runny nose, and ocular symptoms were itchiness and a desire to rub the eyes. Most had gained medication over the counter (73%) with advice from GPs (53%), pharmacists (41%) or a friend or relative (18%). Only 11% consulted an optometrist. Medication was mainly in the form of antihistamine tablets (71%), eye drops (40%) and nasal spray (40%). Those interested in a specialist ocular allergy service (83%) were willing to pay £15.50 on average.

CONCLUSION

Ocular allergy is relatively common, but treatment is often self-managed, does not appear to totally overcome the discomfort and rarely involves a detailed eye examination.

Allergic conjunctivitis and nasal allergy

Allergic conjunctivitis (AC) can be divided into the primary form (caused by an allergic reaction occurring primarily in the conjunctivae) and the secondary form (induced by allergic reaction originating primarily in the nasal mucosa, where the released mediators can reach conjunctiva through the lacrimal system, the blood, the lymphatic network, or the neurogenic network). Patients with primary AC develop an immediate, late, or delayed conjunctival response (CR) during conjunctival provocation tests. Patients with secondary AC develop an immediate, late, or delayed type of secondary CR, induced by the nasal allergic reaction, due to the nasal allergen challenge. Various hypersensitivity mechanisms may be involved in the particular CR types. The secondarily induced AC and CRs can only be confirmed by nasal provocations tests, performed by rhinomanometry combined with recording of conjunctival signs. The existence of the primary and secondarily induced AC has an impact on treatment of this disorder.

Density-equalizing mapping and scientometric benchmarking of European allergy research

Due to the great socioeconomic burden of allergic diseases, research in this field which is important for environmental medicine is currently increasing. Therefore the European Union has initiated the Global Allergy and Asthma European network (GA2LEN). However, despite increasing research in the past years detailed scientometric analyses have not been conducted so far. This study is the first scientometric analysis in a field of growing interest. It analyses scientific contributions in European allergy research between 2001 and 2007. Three different meetings of the European Academy of Allergy and Clinical Immunology were analysed for contributions and an increase in both the amount of research and networks was found.

TSLP and downstream molecules in experimental mouse allergic conjunctivitis

PURPOSE

To explore the potential role of thymic stromal lymphopoietin (TSLP) and its downstream molecules in the development of ocular allergic inflammation using a short ragweed (SRW)-induced mouse model of allergic conjunctivitis (AC).

METHODS

BALB/c mice were topically challenged with SRW pollen after they were sensitized with SRW in the footpad. After the last SRW challenge, the corneal epithelium, conjunctiva, and cervical lymph nodes were harvested for total RNA extraction and gene expression by RT and real-time PCR, and whole eye globes were collected to make cryosections for immunohistochemical staining.

RESULTS

Repeated topical challenges with SRW allergen generated typical signs of AC in mice. Compared with the untreated controls, TSLP mRNA expression and immunoreactivity were significantly increased in the corneal and conjunctival epithelia of SRW-induced AC mice. CD11c(+) and OX40L(+) immunoreactive cells largely infiltrated the conjunctiva with increased mRNA levels of CD11c, TSLPR, and OX40L detected in the corneal epithelium, conjunctiva, and cervical lymph nodes. CD4(+) Th2 cell infiltration was evidenced by increased levels of mRNA and immunoreactivity of CD4, IL-4, IL-5, and IL-13 in the ocular surface, mainly in the conjunctiva, accompanied by increased expression of OX40, STAT6, and GATA3, in AC mice. The maturation of immature DCs was observed with the use of TSLP containing conditioned media from corneal epithelial cultures exposed to polyI:C, which stimulates TSLP production.

CONCLUSIONS

This study provides new findings regarding the role of local mucosal epithelial cells in the initiation of ocular allergic inflammation by producing a novel proallergic cytokine, TSLP, which activates dendritic cells to prime Th2 differentiation and allergic inflammation through the TSLP-TSLPR and OX40L-OX40 signaling pathway.

Vernal keratoconjunctivitis--a rare but serious comorbidity of allergic rhinitis and eustachian tube dysfunction

OBJECTIVE

To determine the prevalence of symptoms and signs of allergic rhinitis (AR) in children with vernal keratoconjunctivitis (VKC) and evaluate eustachian tube (ET) function using tympanometry.

METHODS

The patients underwent an otolaryngological examination and symptoms of rhinorrhoea, nasal obstruction, nasal itching and sneezing were evaluated for the diagnosis of AR. Tympanometry was performed by a middle ear analyzer (Impedance audiometer AZ 26, Interacoustics A/S, Assens, Denmark). Blood samples were collected for determination of peripheral blood eosinophil count (PBEC) and serum total immunoglobulin E (IgE). Allergen sensitivity was also determined by skin prick test.

RESULTS

The study included 26 males (96.3%) and 1 female (3.7%) with a mean age of 12.1+/-4.4 years. Eight out of 27 subjects (29.6%) had blood eosinophilia and 11 out of 27 subjects had elevated serum IgE (40.7%). A positive skin prick test was identified for at least one allergen in 40% of patients (10/25 subjects). Symptoms and signs of AR were found in 10 subjects (37%). Median serum IgE level in subjects with AR (262.5 kU/L) was higher than without AR (40.2 kU/L) (p=0.08), whereas there were no differences in PBEC or eosinophilia percentage (p>0.05). Mean middle ear pressures in the right and left ears were -66.4 daPa (range between -268 and 4 daPa) and -57.3 daPa (range between -308 and 0daPa), respectively. The tympanometry results were abnormal in 5 subjects (18.5%) (3 type C and 2 type B tympanogram). Three out of 10 VKC patients with AR (30%) and 2 out of 17 VKC patients without AR (11.8%) had abnormal tympanograms (p=0.33).

CONCLUSION

AR is commonly associated with VKC and subjects with AR are almost three times more likely to have ET dysfunction than those without. Therefore, opthalmologists should refer VKC patients to otolaryngologists to delineate associated AR and ET dysfunction. Conversely, patients with OME and/or AR who have persistent allergic eye symptoms may well benefit from opthalmologic evaluation for seasonal allergic conjunctivitis and VKC.

Emerging drugs for conjunctivitis

BACKGROUND

Conjunctivitis is a highly prevalent ocular condition with potential complications that include visual impairment. Infectious causes include bacterial, viral, parasitic and fungal etiologies, while noninfectious conjunctivitis is typically owing to allergy, tear film dysfunction or chemical trauma. Treatment requires frequent dosing and often lacks complete efficacy.

OBJECTIVE

The goal of this review is to investigate therapies for conjunctivitis that are undergoing clinical study and development. These data are presented in light of currently available treatment options to provide an understanding of the present and future direction of conjunctivitis management.

METHODS

The Pharmaprojects database was searched for conjunctivitis therapies currently in development around the world. Current treatment guidelines for infectious and noninfectious conjunctivitis were researched through PUBMED and OVID databases.

RESULTS

Several new compounds, including antimicrobial, antihistamine, anti-inflammatory and immunomodulating drugs, along with a novel thiazolidinedione, are currently undergoing investigation for their potential use in conjunctivitis management. These ophthalmic agents show promise in improving clinical outcomes for infectious and noninfectious conjunctivitis.

Intranasal corticosteroids: do they improve ocular allergy?

Allergic rhinoconjunctivitis (ARC) is a commonallergic condition associated with high financial costs and decreased quality of life. Medical treatment options are extensive and include oral, ophthalmic, and intranasal agents. Intranasal corticosteroids (INS) have traditionally been used for chronic management of nasal symptoms, but have also demonstrated an impact on decreasing ocular symptoms of itching, tearing, and redness. Study design, including the method and timing of scoring ocular symptoms, is an important factor affecting whether changes in ocular symptoms are detected in INS clinical trials. INS are thought to exert their influence on the eye through the naso-ocular reflex, and to date their impact on ocular symptoms appears to be a class effect.

Seasonal and perennial allergic conjunctivitis: the possible role of nasal allergy

BACKGROUND

There is a link between conjunctiva and nose. Nasal allergy is suspected to be involved in some cases of conjunctivitis. This work aims to investigate the possible role of nasal allergy in seasonal (SAC) and perennial (PAC) allergic conjunctivitis and the value of nasal challenges with allergens (nasal provocation tests [NPTs]) for the diagnostic procedures of the conjunctivitis.

METHODS

In 61 adults suffering from SAC or PAC with a positive history and skin tests, but responding insufficiently to the local treatment, 122 NPTs and 61 control nasal challenges with phosphate-buffered saline (PBS) were performed using rhinomanometry combined with recording of ocular response. In 16 control subjects suffering only from allergic rhinitis without a history of conjunctivitis, 16 positive NPTs were repeated and supplemented with registration of ocular features.

RESULTS

Of the 61 patients, 55 developed 103 positive nasal responses of various types (P < 0.01), 82 of which were accompanied by significant conjunctival response (P < 0.01) without any corneal involvement. No significant ocular responses were recorded during 61 control PBS challenges (P > 0.05) as well as during 16 challenges in control subjects (P > 0.1).

CONCLUSIONS

These results illustrate a possible involvement of nasal allergy in some patients with allergic conjunctivitis (SAC and PAC) and the value of the nasal challenges with allergen combined with registration of the ocular features in the diagnostic approach to these disorders.