Prevalence of vernal keratoconjunctivitis and its associated factors among children in Gambella town, southwest Ethiopia, June 2018

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.

Vernal Keratoconjunctivitis: A Systematic Review

Vernal keratoconjunctivitis (VKC) is a chronic, bilateral corneal and conjunctival problem which typically presents in young individuals. VKC is characterized by itching, photophobia, white mucous discharge, lacrimation, foreign body sensation, and pain due to corneal involvement of shield ulcers. Vernal keratoconjunctivitis is categorized within ocular diseases. The diagnosis is clinical, as no sure biomarkers pathognomonic of the disease have yet been identified. The VKC therapy relies on different types of drugs, from antihistamines and topical steroids to cyclosporine or tacrolimus eye drops. In extremely rare cases, there is also the need for surgical treatment for the debridement of ulcers, as well as for advanced glaucoma and cataracts, caused by excessive prolonged use of steroid eye drops. We performed a systematic review of the literature, according to PRISMA guideline recommendations. We searched the PubMed database from January 2016 to June 2023. Search terms were Vernal, Vernal keratoconjunctivitis, and VKC. We initially identified 211 articles. After the screening process, 168 studies were eligible according to our criteria and were included in the review. In this study, we performed a systematic literature review to provide a comprehensive overview of currently available diagnostic methods, management of VKC, and its treatments.

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.

Vernal keratoconjunctivitis: Current immunological and clinical evidence and the potential role of omalizumab

Vernal keratoconjunctivitis (VKC) is a severe ocular allergic disease characterized by chronic inflammation of the cornea and conjunctiva that may lead to loss of visual acuity and blindness. The disease occurs primarily in children and is more common in geographical regions characterized by warm temperatures and high humidity. The clinical manifestations of VKC, when inadequately treated, may lead to severe complications and corneal damage. The prevalence of allergen sensitization, specific serum immunoglobulin E (IgE), and specific tear IgE was reported in approximately 55%-60% of patients with VKC, confirming the involvement of IgE-mediated and non-IgE-mediated mechanisms in the pathophysiology of the condition. This article explores current knowledge on the immunological pathways of VKC and the role of the monoclonal anti-IgE antibody, omalizumab, in its management. The review evaluated the effects of omalizumab beyond the direct IgE-mediated reactions and discusses its potential as a therapeutic target for VKC. Multiple retrospective analyses, case series, and case reports have reported the effectiveness of omalizumab in the management of VKC. A summary of the clinical data from these studies revealed that in children with VKC omalizumab treatment was well tolerated with improvement or resolution of ocular symptoms, reduction in steroid use, and enhancement of quality of life. Omalizumab may serve as a promising treatment option for VKC due to its ability to target both IgE-mediated and non-IgE-mediated pathophysiological pathways. Larger, controlled clinical trials are needed to support these findings.

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.

The effect of COVID-19 imposed lockdown on Italian children with Vernal Keratoconjunctivitis

Background

Vernal keratoconjunctivitis (VKC) is a chronic, inflammatory-allergic disease of the cornea and conjunctiva. Environmental factors, such as light exposure, have been supposed to play a role in the pathogenesis of ocular inflammation and in the worsening of VKC.

Objective

The aim of this study was to estimate the impact of reduced sunlight exposure in patients with VKC during the imposed lockdown period for the SARS-CoV-2 pandemic emergency.

Methods

We retrospectively reviewed data of patients with VKC visited during spring season in 2020 and 2019 at Vernal Keratoconjunctivitis Multidisciplinar Outpatient of our Hospital.

Subjective symptoms were evaluated by Visual analogue scale (VAS) and VKC severity was graded by Bonini scale. Quality of life was evaluated by Correlations of Quality of Life in Children with Vernal Keratoconjunctivitis (QUICK) questionnaire. The number of hours of e-learning as well as of hours spent in front of a bright screen (PC, TV, mobile, tablet play station, and so on) was also investigated.

Results

Twenty-nine male subjects (mean ± SD age: 8.74 ± 2.40 years) with VKC were included in the study. Most of the patients (17/29) were sensitized individuals.

No significant changes in Bonini severity score and in VAS evaluation were observed comparing 2020 to 2019 values. Ten (34.4%) patients did benefit from the reduced sunlight exposure. The increased use of bright screens was associated with worsening of VKC severity.

Conclusions

Sunlight exposure plays a role in VKC exacerbation in about one third of patients. The number of hours spent in front of bright screens may influence severity of VKC symptoms.

Knowledge, Attitude, and Practice Among Caregivers of Children With Vernal Keratoconjunctivitis in a Tertiary Care Pediatric Hospital

PURPOSE

To determine the knowledge and attitude about vernal keratoconjunctivitis (VKC) and factors affecting the practice and compliance with treatment in caregivers of children with VKC.

METHODS

The study was conducted in a tertiary care pediatric hospital in northern India. It was a hospital-based cross-sectional study in which 65 caregivers (parents or guardians) were interviewed regarding their knowledge about the disease and attitude of caregivers.

RESULTS

Of 268 children with VKC visiting the ophthalmology department during the study period, 65 children met the inclusion criteria; 53 (81.54%) were boys and 12 (18.46%) were girls. A total of 69.2% of caregivers were not aware of the symptoms of the disease and 83% of caregivers were unaware of the side effects of eye drops used. A total of 24.61% of caregivers considered VKC affected school hours and other recreational activities of children (P < .001). Compliance with treatment decreases with more episodes of VKC and longer duration of symptoms.

CONCLUSIONS

The chronic course of the disease affects compliance with treatment and follow-up with an eye specialist. Proper education of caregivers of children with VKC can influence the compliance with treatment. [J Pediatr Ophthalmol Strabismus. 2021;58(6):390-395.].

Prevalence and patterns of childhood ocular morbidity in Kinshasa. A population-based study

Context

Childhood ocular disorders can seriously impact on development and education, future employment opportunities and quality of life, their consequences are especially severe in low resource settings. There is a lack of data on pattern and prevalence of ocular morbidities among children in Democratic Republic of the Congo (DRC).

Objective

The aim of this study was to determine the pattern and magnitude of childhood ocular disorders in children in Kinshasa, the capital city of DRC.

Methods

A population-based cross-sectional study was conducted from July to August 2017. Children aged less than 16 years old were screened by volunteers in households and those with ocular pathologies were examined by two ophthalmologists. Prevalence and pattern of ocular diseases were determined.

Results

A total of 4307 households were visited by the surveyors and 13,197 children were screened. Ocular pathologies were diagnosed among 399 children. Girls represented 50.7% of the children and the mean age ± SD was 9.2 ± 4.1 years. The overall prevalence of ocular morbidity in our population was 3.6% [95% CI 3.3-3.9]. Allergic conjunctivitis was the most frequent pathology (56.2%) followed by refractive errors (27.4%) and strabismus (5%). Age of children was the only risk factor with a significant impact on the frequency of ocular pathology. Forty-five percent of children had never benefited from any treatment, self-medication, and recourse to traditional treatments concerned respectively 18.%, and 2.3% of children.

Conclusion

Childhood ocular morbidity in Kinshasa city was dominated by allergic conjunctivitis and refractive errors. The frequency of these conditions varies depending on the age of the children. Very few parents consult medical staff when their children have ocular problems, ignorance and limited financial resources are the principal barriers to consult.

The effects of the COVID-19 pandemic on the treatment of allergic eye diseases

PURPOSE OF REVIEW

To analyze if recommendations given before and during the COVID-19 pandemic are still a valid option for patients suffering of ocular allergy (OA).

RECENT FINDINGS

During the last year many doctors and patients requested suggestions for the treatment of OA patients in COVID-19 time. Most of them were given by phone calls and emails following the recommendations given by Scientific Societies.

SUMMARY

Considering the current multiple problems related to the COVID-19 pandemic, OA has not been considered a priority, even though patients need treatments. Topical antiallergic drugs are still the first option to treat all kind of OA, with the addition of topical corticosteroids in the severe forms of vernal and atopic keratoconjunctivitis (VKC and AKC) even in patients at risk of COVID-19. Topical immunomodulation is still recommended in severe forms of VKC and AKC unless the patient is infected. The number of patients treated with these drugs in our Center was similar than previous years. The risk to have a VKC patient affected by COVID-19 is similar to the general pediatric population but with a lower OR. In 2021, still in COVID-time, the management of OA should follow the previous recommendations with an update due to the risk of infection.

Immunopharmacology in Vernal Keratoconjunctivitis: Current and Future Perspectives

Vernal keratoconjunctivitis (VKC) is a complex and chronic, multifactorial Th2 cell-mediated chronic ocular surface inflammatory condition that typically affects predominantly male children in hot or warm climates. The primary symptom is intense ocular pruritus, often significant enough to affect activities of daily living. Clinical features differ from simple forms of allergic conjunctivitis in that they are more-or-less confined to the superior tarsus and limbus. There is also a risk of corneal involvement, which leads to irreversible vision loss in approximately 6% of patients. Right now, there is no standardized treatment protocol, and many of the currently available options are not effective in severe and recurrent cases. As such, it is imperative to understand this complex allergic immune response in order to identify future therapeutic targets. This review will focus on potential drug targets in VKC, with particular emphasis on immunomodulators and immunobiologic agents.

Keratoconus in Africa: A systematic review and meta-analysis

PURPOSE

The aim of this review is to evaluate the prevalence of and factors associated with keratoconus in Africa.

METHOD

A systematic online literature search was conducted for articles on keratoconus in Africa. Meta-analysis was performed to estimate the prevalence of keratoconus in Africa. The Freeman-Tukey double arcsine transformation was used to minimize the effects of studies with extremely high or low prevalence estimates on the overall pooled estimates. Leave-one-out sensitivity analysis was used to assess the robustness of the pooled effects and potential outliers. Meta-regression was performed to explore associations between keratoconus, gender and age.

RESULTS

Twelve studies were included in the review; 5 from Egypt, 2 from South Africa, 2 from Kenya, 1 from Sudan, 1 from Ghana and 1 from Nigeria. Two studies were conducted in allergic conjunctivitis patients, 4 in keratoconus patients, 1 in contact lens service seekers, 1 in pre-LASIK patients, 1 in refractive patients and 1 in a student population. Eight studies were included in the meta-analysis. The overall prevalence estimate of keratoconus in Africa was 7.9% (95% CI: 2.5%-16.0%). The prevalence of keratoconus among males and females in Africa was estimated to be 9.3% (95% CI: 2.5%-19.5%) and 5.8% (95% CI: 1.5%-12.7%) respectively. The estimated prevalence of unilateral and bilateral keratoconus was 2.6% (95% CI: 0.4%-6.5%) and 5.8% (95% CI: 1.6%-12.3%), respectively. The estimated prevalence of mild keratoconus was 2.2% (95% CI: 0.7%-4.7%), moderate keratoconus was 3.5% (95% CI: 0.0%-11.8%) and severe keratoconus was 4.0% (95% CI: 0.0%-19.6%). There was no significant association between gender and the prevalence of keratoconus in Africa (p = 0.63), and age and the prevalence of keratoconus in Africa (p = 0.78).

CONCLUSION

The estimated prevalence of keratoconus reported here is higher than prevalence values reported in other meta-analyses or different geographical locations. This is mainly because studies included in this meta-analysis were either conducted on a cohort at high risk of keratoconus or a population with high possibility of finding keratoconus patients. There is a dearth of well-designed population-based studies on keratoconus in Africa, resulting in a lack of epidemiological information. This highlights the urgent need for research on keratoconus in Africa.

Epidemiological aspects of allergic conjunctivitis

The prevalence of ocular allergies has been increasing worldwide for the past several decades. The geographical distribution and hot spots of rhinoconjunctivitis have been documented in a global survey by the International Study of Asthma and Allergies in Childhood (ISAAC). ISAAC indicated that Africa, Latin America, and Japan were notable for their high prevalence of rhinoconjunctivitis. The outcomes of follow-up studies of regional differences and the characteristics of allergic conjunctivitis are summarized in this review. Currently, comorbid diseases and socioeconomic and environmental factors, including climate and air pollution, are proposed to contribute to the regional differences in the prevalence of allergic conjunctivitis. Of them, rhinitis has been shown repeatedly to be significantly associated with allergic conjunctivitis. Their mechanistic aspects on association with the prevalence of systemic allergic diseases have been reviewed by examining the birth cohort or in vitro analyses. A vision threatening form of ocular allergy, vernal keratoconjunctivitis, is prevalent in the African countries and Japan. Of the proposed associated factors, air pollution was shown to contribute not only to aggravating the symptoms but also to the increase in the incidence of its severe forms. Its mechanistic aspects are discussed in this review in the context of comorbid diseases.

Understanding vernal keratoconjunctivitis in children

Background: Vernal keratoconjunctivitis (VKC) is a public health problem that mostly affects children in warm subtropical climates. Unfortunately, the causative factors of the disease are not clearly defined, thus posing a serious management challenge to healthcare providers. It is therefore argued that understanding the pathogenesis of the disease and how various inflammatory cells affect the conjunctiva and the cornea may assist in the management of the disease.Aim: As visual impairment and avoidable blindness are indicated, it is advisable for optometrists to understand the clinical presentation of this chronic condition in order to initiate appropriate interventions and/or immediate referrals where necessary.Methods: A thorough literature search was conducted on peer-reviewed publications on VKC and children. All material obtained were then studied and the information extracted was used to document relevant information required for understanding VKC amongst children.Results: The results in the studied material revealed that VKC was prevalent amongst children aged 2 to 18 years, affecting mostly male children of African and Indian origins. Different strategies of management of the disease have been proposed, including but not limited to explaining to parents the nature of the disease, environmental strategies and preventive measures as well as possible surgical intervention.Conclusion: In view of the nature of this disease, healthcare providers should therefore seek to understand the history of the patient better when such patients present for their first consultation in order to develop a comprehensive management approach.

The prevalence of keratoconus in children with allergic eye disease in an Egyptian population

PURPOSE

To determine the prevalence of keratoconus (KC) among children with ocular allergy.

METHODS

A cross-sectional study was conducted on all children presenting with ocular allergic disease from September 2017 to September 2018. All study participants were subjected to history taking (a specially designed questionnaire), routine ophthalmological examination, and corneal tomography.

RESULTS

A total of 79% of the study patients had vernal keratoconjunctivitis (VKC) while the remaining had perennial allergic conjunctivitis (10%), seasonal allergic conjunctivitis (9%) and atopic keratoconjunctivitis (2%). Manifest KC was seen in 7% of cases, suspect KC was found in 27% of cases, and 66% had no evidence of KC. For the manifest KC, 56% had clinical signs, while 44% were diagnosed by tomography. For the purpose of statistical analysis, the cohort was divided into group KC (manifest or suspicious KC) and group non-KC (no KC). The mean age was 11.2 years in group KC, and 9 years in group non-KC (p < 0.001). The mean duration of allergic symptoms was 3.75 years in group KC, and 2.5 years in group non-KC (p = 0.001). The mean duration of eye rubbing was 2.5 years in group KC, and 0.83 years in group non-KC (p = 0.02). Systemic atopy was present in 35.3% of group KC, and in 12.5% in group non-KC (p = 0.005).

CONCLUSION

The overall prevalence of KC was 34%. Risk factors for the development of KC in patients with ocular allergy were age, duration of symptoms specially eye rubbing, systemic atopy and VKC. Tomographic diagnosis of KC can be present in absence of clinical signs.

Air pollution significantly associated with severe ocular allergic inflammatory diseases

Ambient air pollution is a well-recognized risk for various diseases including asthma and heart diseases. However, it remains unclear whether air pollution may also be a risk of ocular allergic diseases. Using a web-based, nation-wide, cross-sectional study design, we examined whether the level of ambient air pollution is significantly associated with the prevalence of ocular allergic diseases. A web-based questionnaire was posted to invite the participants who are members of the Japan Ophthalmologist Association and their family members. The answers from 3004 respondents were used to determine whether there were significant associations between the level of the pollutants and the prevalence of ocular allergic diseases. The study period was between March to May 2017. The data of the air pollutants during 2012 to 2016 were obtained from the National Institute for Environmental Studies. The prevalence of allergic diseases was calculated by post stratification and examined for significant associations with the level of pollutants using multiple logistic regression analyses. The prevalence of seasonal allergic conjunctivitis, perennial allergic conjunctivitis, atopic keratoconjunctivitis (AKC), and vernal keratoconjunctivitis (VKC) in Japan was 45.4%, 14.0%, 5.3%, and 1.2%, respectively. The high prevalence of the severe forms of allergic conjunctivitis, including AKC and VKC, were significantly associated with the levels of the air pollutants. The prevalence of AKC was significantly associated with the levels of NO₂ with an odds ratio (OR) of 1.23 (per quintile). The prevalence of VKC was significantly associated with the levels of NO_x and PM₁₀ with ORs of 1.72 and 1.54 respectively. The significant associations between the prevalence of AKC and VKC and the levels of air pollutants indicate that clinicians need to be aware that air pollutants may pose serious risks of vision threatening severe ocular allergy.

Allergic eye disease in children and adolescents seeking eye care in India: Electronic medical records driven big data analytics report II

PURPOSE

To describe the demographics, clinical presentation and risk-factors of allergic eye disease (AED) in children and adolescents presenting to a multi-tier ophthalmology hospital network in India.

METHODS

This was a hospital-based cross-sectional study of 259,969 new patients (≤21 years of age) presenting between 2010 and 2018. Patients with a clinical diagnosis of AED were considered as cases. Data were collected using an electronic medical record system. Multiple logistic regression with odds ratios (OR) was performed to identify the high risk-factors of AED.

RESULTS

Overall, 26,309 (10.1%) children and adolescents were diagnosed with AED. The prevalence of AED was 0.3%, 6.6%, 18.3%, 15.8%, 8.1%, and 4.9% in infancy (<1 years), toddlerhood (1-2 years), early childhood (3-5 years), middle childhood (6-11 years), early adolescence (12-18 years) and late adolescence (18-21 years), respectively. Most patients with AED presented in spring and summer. Palpebral vernal keratoconjunctivitis was the commonest clinical form, seen in 42.8% of eyes. Corneal scarring, keratoconus, limbal stem cell deficiency and shield ulcers were seen in 2.4%, 1.4%, 0.4% and 0.3% of eyes, respectively. Male sex (OR 2.05); early and middle childhood age groups (OR 66.6; 59.1); higher socio-economic class (OR 1.46) and history of systemic allergy (OR 3.74) were identified as high-risk factors of AED.

CONCLUSION

About a tenth of the children and adolescents seeking eye care in India are affected by AED, which commonly affects boys with atopy, from middle to higher income families during their early to middle childhood and shows a self-limiting trend by late adolescence.