Sensitization and Clinical Characteristics of Congolese Children with Vernal Keratoconjunctivitis in Kinshasa

Allergen Testing: A Review of the Indications, Procedures, and Limitations in Ocular Allergy

Allergen-based diagnostics are essential in the management algorithm of allergic diseases. Unlike systemic allergy, where the indications and interpretation of these diagnostic modalities are well established, their utility in ocular allergy is not well-defined. With the rising prevalence of ocular allergies and the need for personalized treatment strategies, there is a growing demand for precision allergen diagnostics. This review describes the commonly used tests with their indications, procedures, and limitations. A review of the literature was carried out on articles on allergen diagnostics in ocular allergy, and after excluding articles that were not relevant, 82 papers were included in the current review. IgE-mediated pathways contribute significantly to seasonal and perennial ocular allergy and partly to vernal keratoconjunctivitis. Most diagnostic techniques aim to detect IgE sensitization. In vivo tests include skin prick (SPT), intradermal, and patch tests. SPT is considered the gold standard and directly evaluates the presence of allergen-specific IgE in the skin. In vitro tests measure total and specific IgE from either tears or sera. Tear IgE measurement is relatively specific for allergic conjunctivitis and can provide insight into the potential allergens responsible for local sensitization. The conjunctival provocation test can help establish true allergy, especially in patients with polysensitization. This review also provides an overview of evidence in literature segregated based on the test employed. This includes 17 studies on only SPT; 42 studies on IgE measured in serum, tears, or both; and 20 studies which have evaluated both SPT and IgE. The pattern of allergen sensitization can guide recommendations for avoidance measures and immunotherapy. Thus, this could create a corticosteroid-sparing therapy avenue in these patients, reducing disease severity and resulting visual morbidity.

Unraveling the complexity - Insights and interventions of refractory vernal keratoconjunctivitis

Vernal keratoconjunctivitis (VKC) is a chronic severe ocular allergic inflammation mostly observed in children and young adults. The ocular manifestations are the expression of multifactorial immune mechanisms that generally have a good prognosis, however long-term inflammation may remarkably reduce the visual function due to complications and poor therapeutic responses. Lack of responsiveness to a drug or treatment is relatively common in VKC and it is not only due to corneal involvement, which is considered the main sign of severity. The concept of refractory may be relative to multiple factors including the clinical condition, systemic co-morbidities, previous or concomitant drugs or regiments, compliance, patient's psychological condition or expectations, type of exposome and environmental conditions, doctor's experience and expectations, or timing of clinical evaluation. In this narrative review, the authors propose a definition of refractory VKC based on revised literature and clinical experience and consider potential new treatments for refractory patients and surgical management in case of complications.

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

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

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.