The Prevalence of Ocular Allergy and Comorbidities in Chinese School Children in Shanghai

Allergen-specific IgE in the tear fluid of Chinese patients with common allergic conjunctivitis in autumn and winter

PURPOSE

In this study, we determined the positive rates of allergen-specific immunoglobulin E (IgE) in the tear fluid of Chinese patients with common allergic conjunctivitis (AC) in autumn and winter, compared systemic and ocular allergen tests, and explored the correlation between the numbers and categories of allergens and clinical AC features.

METHODS

This cross-sectional study recruited 44 patients with AC (86 eyes). Specific IgEs for allergens common in China (house dust mite, cat/dog dander, mugwort/ragweed pollen, cottonwood/willow/elm pollen, milk, egg whites, soybeans) were measured in collected tears using kits for allergen-specific IgE antibodies. AC signs and symptoms were graded according to severity.

RESULTS

Specific IgE in tears was positive in 87.2% of eyes. House dust mite was the most common allergen (86.0%), followed by cat (24.4%) and dog (7.0%) dander; tree and grass pollen accounted for only 4.7% and 2.3%, respectively. Food allergens were not detected. The positive rates of the systemic allergen tests were lower than in tear fluid tests in both eyes, especially for house dust mites (P = 0.000). In patients with more allergens, itching was more severe (P = 0.035), while conjunctival hyperemia was milder (P = 0.002).

CONCLUSION

In autumn and winter, the most common AC allergen in Chinese patients was house dust mites. Compared with systemic allergen tests, measuring specific IgE in tears may be a non-invasive method to diagnose and evaluate AC severity, which may be more suitable to reflect the local conditions of ocular surface inflammation due to its high positive rate and convenience.

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.

Effect of Anti-allergic Therapy on Quality of Life in Children with Allergic Conjunctivitis and Their Parents

PURPOSE

To evaluate the effect of anti-allergic therapy on quality of life (QoL) in children with allergic conjunctivitis (AC) and their parents.

METHODS

Prospective single-arm intervention study including 55 AC child-parent pairs. The endpoint was that AC was successfully controlled after anti-allergic therapies. The primary outcome was the change in QoL of children from baseline to endpoint as measured by the total Pediatric Quality of Life Inventory (PesdQL) score.

RESULTS

The total PedsQL scores of children and parents were improved after treatment (P < .001). QoL improved greater in children with vernal keratoconjunctivitis/atopic keratoconjunctivitis, those without other allergy outside the eye, and those with lower baseline total PedsQL score. Greater improvement of parents' QoL was associated with longer treating duration, greater improvement of children's QoL, lower baseline parents' total PedsQL score, and more severe baseline children's signs.

CONCLUSION

Both pediatric AC patients' and their parents 'reduced QoL were improved after anti-allergic therapy.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trial Registry Identifier: ChiCTR2000037866.

Association between keratoconus and allergic conjunctivitis in children attending a Tertiary Hospital in Nigeria

Objective: To ascertain an association between keratoconus and allergic conjunctivitis and to know if it is necessary to investigate all patients with allergic conjunctivitis for keratoconus. Methods: A hospital-based prospective study in which the eyes of children presenting with ocular allergic diseases were examined. Social demographics and clinical data were captured in a questionnaire. All the patients underwent keratometry using the autorefractor-keratometer and the pachymeter was used to measure the central corneal thickness. Data analysis was done with IBM SPSS version 28 for Windows. Frequency and chi-square were used as descriptive statistics to determine the association between dependent and independent variables. Inferential statistics using one-way ANOVA and t-test. P - Value at <0.05 was considered statistically significant. Results: 121 children with allergic conjunctivitis were reviewed. Males were 72 and females 49. The visual acuity was 6/ 6-6/ 18 in 116, and mild visual impairment - 6/ 18-6/ 60 in 5. The most common complaint was frequent itching in 109 (90.1%). Keratometry was normal in 120 (99.5%), while probable keratoconus was found by keratometry in only one patient (0.5%). Central corneal thickness was within the normal range in 33 (27.3%) children, 43 (35.5%) had thin corneas, while 45 (37.2%) had cornea thickness of more than 560 microns. Discussion: Pediatric keratoconus tends to be more aggressive than adult keratoconus with an increased risk of corneal opacities and subsequent keratoplasty. As a result of these negative impacts, early detection and prompt treatment are mandatory. Conclusion: The prevalence of keratoconus was not found to be high in this study population, but with facts emerging between the association of allergic conjunctivitis, and increased prevalence of keratoconus, it is pertinent to integrate keratoconus screening as part of the management of allergic conjunctivitis using an appropriate tool such as video keratography and slit lamp biomicroscope. Abbreviations: KC = Keratoconus, CLEK = Collaborative Longitudinal Evaluation of Keratoconus, SAC = Seasonal Allergic Conjunctivitis, PAC = Perennial Allergic Conjunctivitis, VKC = Vernal Keratoconjunctivitis, IOP = Intraocular Pressure, CCT = Central Corneal Thickness, TNF-α = Tumor Necrosis Factor-Alpha, IL = Interleukin.

A survey of allergic conjunctivitis in children in China

To explore the risk factors for allergic conjunctivitis (AC) in Chinese children. We recruited 176 children who suffered from AC and a control group comprising 131 normal subjects in southern China. Each participant completed a questionnaire and underwent multiple eye examinations and a skin prick test (SPT). The data of the questionnaire, the scores of the symptoms/signs and the results of the SPT were analysed. The rate of parental allergic history in the case group was much higher than that in the control group (P < 0.01). Compared with the control group, the case group was more likely to have other concomitant diseases (P < 0.01). The scores of ocular symptoms/signs had a significant correlation with the clinical duration of AC in the case group (P < 0.01). Children with other concomitant diseases or a parental allergic history were more likely to have AC.

Association of different digital media experiences with paediatric dry eye in China: a population-based study

OBJECTIVE

To investigate the ocular surface effects of different digital media experiences in Chinese elementary school students.

DESIGN

Population-based cross-sectional study was used.

SETTING

14 randomly selected primary schools in Yuhuatai District, Nanjing, China PARTICIPANTS: 2,694 students between 7 and 8-year-old.

OUTCOME MEASURES

Prevalence of and risk factors for different types of dry eye disease，and different digital media experience with different ocular signs.

RESULTS

The prevalence of 'symptomatic DED' was 8.7% (95% CI 7.6% to 9.8%) and 'definite DED' prevalence rate was 5.5% (95% CI 4.7% to 6.4%). In multivariable logistic regression model, allergic conjunctivitis (OR=4.33, 95% CI (3.01 to 6.23), p<0.001), more than 1 hour per day on outdoor activity (OR=0.69, 95% CI (0.49 to 0.99), p=0.043), smartphone (OR=2.73, 95% CI (1.51 to 4.91), p=0.001), tablet (OR=2.09, 95% CI (1.07 to 4.07), p=0.030) and homework (OR=1.86, 95% CI (1.22 to 2.83), p=0.004) were independently associated with 'definite DED', while allergic conjunctivitis (OR=5.58, 95% CI (4.12 to 7.55), p<0.001), more than 1 hour per day on outdoor activity (OR=0.72, 95% CI (0.53 to 0.97), p=0.028), smartphone (OR=2.60, 95% CI (1.55 to 4.35), p<0.001), tablet (OR=1.84, 95% CI (1.02 to 3.34), p=0.044) and homework (OR=2.57, 95% CI (1.84 to 3.60), p<0.001) were independently associated with 'symptomatic DED'.

CONCLUSIONS

Using smartphones or tablets for an average of more than 1 hour per day through the course of a year is independently associated with paediatric DED.

Combination Therapy of 0.1% Fluorometholone and 0.05% Azelastine in Eyes with Severe Allergic Conjunctival Diseases: A Randomized Controlled Trial

This study sought to evaluate the efficacy of the isolated use of fluorometholone compared with the combined use of azelastine and fluorometholone for the treatment of severe allergic conjunctival disease (ACD). One hundred and eleven patients with severe ACD were randomized into two groups: one treated with topical 0.1% fluorometholone combined with 0.05% azelastine and the other with 0.1% fluorometholone alone. The Ocular Surface Disease Index (OSDI) and the signs of keratopathy, palpebral conjunctiva papillae and conjunctival congestion were scored before and at one, two and six weeks after treatment and compared between the groups. The intra-ocular pressure (IOP) was also monitored. There were no significant differences between the groups in the baseline mean scores of signs and OSDI scores, which gradually improved at all visits after therapy in both groups. Although the time effect was significant for all the parameters (all p < 0.001), the reduction in corneal involvement scores from week 2 to week 6 was insignificant in both groups (p = 0.460 for the steroids group and p = 0.074 for the combination group). All signs and symptoms were significantly more improved in the combination group than in the isolated group at each control visit. IOP remained stable at all visits (all p < 0.001), except one patient in each group had elevated IOP over 21 mmHg. While both the isolated use of fluorometholone and combined use of azelastine and fluorometholone are effective in alleviating the signs and symptoms of severe ACD, optimal response can be achieved with adjunctive treatment including azelastine.

Altered retinal nerve fiber layer thickness in children with allergic conjunctivitis: the Nanjing eye study

Background

So far, few data are available on the relationship between allergic conjunctivitis (AC) and ocular fundus. Whether retinal parameters change in patients with AC remains unknown. In this study, we investigated the influence of AC on retinal thickness and vessel density among 7-years-old school-age children.

Methods

This large population-based study is part of the Nanjing Eye Study (NES). Comprehensive examinations including anthropometric parameters, refraction, ocular biometric parameters, intraocular pressure and retinal parameters were conducted on each child. Retinal thickness and vessel density were assessed using the optical coherence tomography angiography. Information on AC was obtained from a comprehensive questionnaire.

Results

A total of 739 children (mean age ± SD: 7.40 ± 0.29 years) had complete eye examination and questionnaire data we needed. Ninety-four children (12.7%) had AC, among which, 5 children had the history of corticosteroid use and were excluded from the final analysis. Spherical equivalent, axial length, body mass index and birth weight were correlated with retinal parameters. After adjusting for sex, age, spherical equivalent, axial length, body mass index, birth weight and premature history, children with AC had thinner retinal nerve fiber layer thickness for average (117.39 versus 120.97 μm, p = 0.007), temporal (80.73 versus 84.34 μm, p = 0.001), nasal (98.82 versus 102.18 μm, p = 0.049) and inferior (152.68 versus 157.06 μm, p = 0.034) quadrants than the control group.

Conclusions

Children with AC tended to have thinner retinal nerve fiber layer thickness. More attention is needed to fundus condition of children with AC.

Supplementary information

The online version contains supplementary material available at 10.1186/s12886-022-02399-7.

Morphological and Functional Changes of Meibomian Glands in Pediatric and Adult Patients with Allergic Conjunctivitis

Allergic conjunctivitis (AC) is one of the most common ocular disorders in clinical practice and is associated with meibomian gland dysfunction. This study aimed to explore the morphological and functional changes of meibomian glands (MGs) in pediatric and adult patients with AC and to analyze their potential predictors. In our prospective, observational cohort study, a total of 59 patients with AC were enrolled, with 30 patients aged ≤16 years in the pediatric group and 29 patients in the adult group. All patients underwent examinations at baseline and last visit when the complete resolution of conjunctival papillae was identified. An automatic MG analyzer was used to measure the morphological and functional parameters of MGs, including their area ratio (GA), tortuosity index (TI), and signal index (SI). Two groups were comparable at baseline in terms of characteristics and MG parameters (p > 0.05). The morphological (length, square, and GA) and functional MG parameters (SI) of AC patients significantly improved in the pediatric group after treatment (all p < 0.05), but not in the adult group. The change in the GA correlated with age, sex, GA, TI, and SI at baseline (all p < 0.05). Age (p = 0.001) and GA (p < 0.001) at baseline were predictors of an improvement in the GA of MGs. The findings showed that the structure and function of MGs in pediatric patients with AC seem to improve after the conjunctival papillae disappear, but not in adult patients.

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.

Early Life Domestic Pet Ownership, and the Risk of Pet Sensitization and Atopic Dermatitis in Preschool Children: A Prospective Birth Cohort in Shanghai

Background: Although domestic pet ownership is on the rise, the impact of early life pet ownership on children's pet sensitization and atopic dermatitis (AD) remains controversial. Methods: Shanghai Allergy Cohort is an ongoing prospective study followed up to the age of 5 years. Pregnant mothers were recruited and their offspring were followed up every year by a group of pediatricians. Information on furred pet ownership was collected by the questionnaire. AD was diagnosed by dermatologists according to disease history and Williams criteria at 5 years ± 1 months. Skin prick test (SPT) was performed to determine sensitization to specific allergens. Multiple logistic regression models were used to evaluate the associations between pet ownership and AD, dog/cat sensitization. Results: In the 538 children at preschool age, 112 (20.82%) were diagnosed with AD. Dermatophagoides pteronyssinus and Dermatophagoides farina were the most common allergens, and almost 10% of children were positive to dog and cat. The percentage of positive SPT reactors at 5-year old was 65.28% in the group of children with AD, higher than that in non-AD group (44.57%). Domestic pet ownership at both infant and preschool period was positively associated with an increased risk of sensitization to dog (OR _adjusted = 2.85 [95% CI: 1.08-7.50 for infant exposure], OR _adjusted = 2.73 [95% CI: 1.33-5.61] for preschool exposure), and interestingly, pet ownership at infant period negatively associated with higher risk of AD at 5-year old (OR adjusted = 0.33 [95% CI: 0.12-0.88]). Conclusion: This is the first prospective birth cohort study in Shanghai that found half of preschool children had positive allergen sensitization even in the non-AD children. Although early life exposure to dog may increase the risk of dog sensitization, it significantly decreased the risk of AD. The underlying mechanisms warrant further investigations.

Diagnosing and managing allergic conjunctivitis in childhood: The allergist's perspective

Allergic conjunctivitis in childhood often poses problems of diagnosis and management for the allergist. We present the salient points concerning the diagnosis and treatment of ocular allergy emerging from a large cohort survey conducted jointly in the departments of ophthalmology and paediatric allergy in a French teaching hospital. Seasonal acute conjunctivitis is a common disorder and not overly difficult to diagnose and treat when associated with rhinitis leading to allergic rhinoconjunctivitis. An ophthalmologist should be consulted when conjunctivitis occurs alone and if another form of conjunctivitis is suspected, such as perennial allergic conjunctivitis, vernal keratoconjunctivitis or atopic keratoconjunctivitis. When IgE-mediated hypersensitivity assessment does not establish aetiological diagnosis, a conjunctival allergen provocation test can be performed. The principal non-IgE-mediated allergy is chronic blepharoconjunctivitis. The main problem for differential diagnosis is the presence of signs suggestive of dry eye. Management includes non-pharmacological treatments, such as lacrimal substitutes, avoidance measures and protection of the ocular surface. Second-line treatment consists of eye drops, preferably single dose or without additives and with dual local action, mast cell stabilizer action and antihistaminic action. Third-line treatment is reserved for severe forms. Short-lasting local steroid therapy can control flare-ups of allergic keratoconjunctivitis, which should have specialized follow-up. Cyclosporine is a disease-modifying treatment, which is both effective and well tolerated.