A red-eye presentation concerning for vernal keratoconjunctivitis: a case report

A red-eye presentation concerning for vernal keratoconjunctivitis: a case report | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report A red-eye presentation concerning for vernal keratoconjunctivitis: a case report Lauren Wong, Samira Jeimy This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8303091/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 06 Apr, 2026 Read the published version in Allergy, Asthma & Clinical Immunology → Version 1 posted 9 You are reading this latest preprint version Abstract Background: Vernal keratoconjunctivitis (VKC) is a chronic, recurrent, and seasonally exacerbated allergic eye disease that can significantly impair quality of life in children. It is a rare disease, with higher prevalence in hot and dry climates. There is a broad differential for a red eye presentation, and the diagnosis of VKC may be complicated when symptoms occur outside typical seasonal patterns or when allergy testing is unclear. We present a case of VKC in Canada, identified on allergy consultation after persistent unresponsiveness to antihistamine treatment. Case presentation: An 11-year-old male presented with a six-month history of bilateral conjunctival redness and swelling, accompanied by seasonal nasal and palatal itch and sneezing. Initial symptoms began atypically in February, later progressing to photophobia and early vision changes. Clinical images showed striking perilimbal Horner-Trantas dots and marked conjunctival inflammation, ecchymosis, and chemosis. Skin prick testing and serum IgE revealed only mild sensitization to cat dander. Multiple topical therapies were trialed; symptoms improved with olopatadine and fully resolved with loteprednol, though attempts to taper the steroid resulted in recurrence. Given clinical features and photographic evidence, VKC was diagnosed, with consideration that persistent environmental cat antigen exposure may have contributed to symptom chronicity. Atopic keratoconjunctivitis and giant papillary conjunctivitis were on the differential but felt to be less likely. The patient was transitioned back to olopatadine to facilitate discontinuation of loteprednol, and was treated with rupatadine for ocular and nasal symptoms. Ophthalmology assessment occurred after he had been off topical steroids for one month, at which time symptoms were minimal and no further suggestions made. Over the following year, he remained stable on daily Pataday and oral rupatadine, ultimately discontinuing antihistamines entirely with only mild intermittent ocular pruritus and conjunctivitis. Repeat skin testing was unremarkable. Conclusions: VKC is uncommon in Canada, but missing it has serious consequences including progressive vision loss. This case highlights VKC in an 11-year-old boy who was repeatedly treated for presumed allergic conjunctivitis despite photophobia and early vision changes. His symptoms presented outside of typical seasonal patterns, with no clear provoking allergen. Successful long-term symptom control was achieved through careful tapering of topical steroids combined with targeted antihistamine therapy. VKC should be considered in cases of conjunctivitis unresponsive to antihistamine therapy, and is important to differentiate from other forms of allergic conjunctivitis to avoid possibly permanent ocular sequelae. A positive skin prick test or serum IgE is not necessary for the diagnosis of VKC. The exact allergen may not be known. Topical and oral antihistamine combination is effective in stabilizing VKC symptoms, with the addition of topical steroids if needed for flares. VKC treatment can require a prolonged course. Referral to ophthalmology for VKC may be considered when vision changes are involved. conjunctivitis vernal keratoconjunctivitis red eye Figures Figure 1 Background VKC is a rare allergic inflammatory disease that affects the ocular conjunctiva and cornea. It is thought to be caused by allergen exposure that triggers mast cell activation in conjunctival tissue. 1 Eosinophils have also been implicated, making up the majority of conjunctival secretions in these patients. 1 It most commonly affects males in early to mid-childhood living in hot and dry climates such as the Mediterranean, Middle East, and Central and South America where there is high dust and sunlight exposure. 1 , 2 A positive family history of allergic disease is present in 40–50% of cases, and personal history of atopy including asthma, eczema, or rhinitis is present in about 46% of cases. 3 VKC is classically characterized by bilateral itchy eyes, tearing, discharge, irritation, redness, and photophobia. 4 Episodes are often recurrent with peak incidence in the spring or summer seasons, and the potential to become perennial. 4 Here we present a case of VKC in Canada with chronic symptoms that developed outside of typical seasonal patterns, with no clear provoking allergen. Case presentation An 11-year-old male presented to the Allergy and Immunology clinic with a six-month history of bilateral redness and swelling of the conjunctiva. He had experienced seasonal nasal and palatal itch and sneezing from May to October for the last 3–4 years but had no known atopic history other than resolved preschool asthma. The initial onset of symptoms was in February, however in May of the presenting year he began noticing vision changes and perilimbal white dots. Review of systems was otherwise unremarkable. He tried multiple eyedrops, only experiencing relief with olopatadine (Pataday) eyedrops. Following optometry assessment, he switched to loteprednol steroid eyedrops (Lotemax). He had full resolution of symptoms on Lotemax but flared when attempting to taper off it. He was still using Lotemax, in addition to Omnaris and Aerius as needed at the time of allergy consultation. On physical exam, there were no significant findings other than internal nasal changes characteristic of allergic rhinitis. However, photos from one month prior demonstrated significant conjunctival erythema, ecchymosis, and possible Horner-Trantas dots ( Fig. 1 ) . Skin prick testing was positive to cat dander. Serum IgE was ordered for a broad aeroallergen panel that may not have appeared positive on skin prick due to young age, with only cat returning mildly elevated. The patient initially flared without any clear cat or other significant environmental allergen exposures in February, although based on clinical history and photos during flares, the diagnosis of vernal keratoconjunctivitis (VKC) was made. The cat dander antigen is known to be adherent and persistent nature. It is possible the patient had a large prior contact with cat, and continued exposure to lingering antigen. Atopic keratoconjunctivitis and giant papillary conjunctivitis were also considered. He was advised to restart Pataday eyedrops to facilitate a taper off the Lotemax, and to use rupatadine orally as needed for both ocular and nasal allergic symptoms. He was referred to ophthalmology for consideration of alternate management options, given the impacts of his keratoconjunctivitis on his quality of life. When he was seen, he had been off Lotemax eyedrops for one month, with improvement in ocular symptoms. No changes were made to his treatment plan as he was in low disease activity. He remained stable off Lotemax with no major flares, though continued to have minor conjunctival erythema while on Pataday one drop daily and Rupall 5 mL liquid daily. His Rupall was adjusted from liquid to tablet form and increased to 10 mg oral daily with flexibility to titrate to 40 mg daily. He also continued to use Pataday once daily. The patient remained on this regimen for one year, with no new ocular symptoms. Repeat skin testing did not reveal additional environmental allergens. Within seven months he had completely discontinued antihistamine use, with only intermittent pruritus of the eyes and mild daily conjunctivitis that was not bothersome to him. Prescriptions for oral and topical antihistamines were renewed should his vernal keratoconjunctivitis flare again, and follow-up was left open. Discussion and Conclusions Although the diagnosis of VKC should take into account the history of presenting illness, ocular examination, and investigations, it is largely clinical. Two forms of VKC exist: tarsal which involves the upper tarsal conjunctiva, and limbal which involves the bulbar conjunctiva. 2 , 3 In the tarsal form, there may be erythematous and thickened eyelids and papillae on the upper tarsal conjunctiva with a cobblestone appearance. 3 , 4 Main findings in the limbal form are gelatinous infiltrations around the limbus surrounding the cornea (Horner-Trantas dots), which are focal collections of degenerated eosinophils and epithelial cells. 4 The mixed form has features of both. In this case, the photographic identification of Horner-Trantas dots strongly aided in the clinical diagnosis of VKC. Corneal involvement can also occur in cases where VKC is not adequately or promptly treated, which is why ophthalmology involvement can be important. 5 It will initially present as punctate epithelial erosions with progression to macro erosions and ulcers, causing gradual vision loss. 5 Differential diagnoses include other subtypes of allergic conjunctivitis such as seasonal allergic conjunctivitis, perennial allergic conjunctivitis, atopic keratoconjunctivitis, and giant papillary conjunctivitis. 5 VKC should be suspected when there is failure of treatment with common topical or systemic antihistamines traditionally used in allergic conjunctivitis. 5 Symptoms such as photophobia and ocular pain are more specific for VKC. 5 Not all VKC patients will have positive skin prick tests, and the presentation or flares of the disease are not always associated with large environmental allergen exposure. 4 , 6 This case presented an example of VKC manifesting without positive initial or repeat skin prick tests, and no clear allergen trigger. Approximately 50% of patients with VKC have a negative allergy test, as other non-IgE mechanisms are implicated in the inflammatory reaction of VKC. 6 Treatment is a stepwise approach, with the most important step being the removal of any possible allergens in the patient’s environment. 4 – 6 Conservative management for ocular itching, burning, and irritation includes cold compresses and saline rinses. 5 Antihistamine or mast cell stabilizer eyedrops, or dual acting agents with both, can be added. 4 Olopatadine topical antihistamine eyedrops are commonly used to target the H1 receptors. 4 Corticosteroid eyedrops such as loteprednol and fluorometholone are effective in disease flares, but are not to be used for long-term management. 5 Ideally steroids are used as pulse therapy with a taper in addition to antihistamine or mast cell stabilizers as maintenance therapy, as was done in this case. In more severe disease with persistent inflammation, macropapillae, and ulcers or macro erosions, topical immunomodulators like cyclosporine and tacrolimus may be considered. 4 Generally, VKC is a self-limiting disease with spontaneous resolution around puberty. 2 – 6 Abbreviations VKC Vernal keratoconjunctivitis Declarations Ethics approval and consent to participate Not applicable Consent for publication Consent form obtained. Please request if a copy is required. Availability of data and materials Not applicable. Competing interests The authors declare that they have no competing interests. Funding No sources of funding to declare. Authors’ contributions SJ was the physician in charge of the clinical care of the patient described in the case report. SJ obtained informed consent and sourced clinical images from the patient and guardian. LW edited the clinical images. SJ and LW were responsible for drafting of the text and both read and approved the final manuscript. Acknowledgements Not applicable. Footnotes Not applicable. References Doan S, Papadopoulos NG, Lee JK, Leonardi S, Manti S, Lau S et al. Vernal Keratoconjunctivitis: Current immunological and clinical evidence and the potential role of omalizumab [Internet]. U.S. National Library of Medicine; 2023 [cited 2025 Dec 7]. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC10300397/ Di Zazzo A, Zhu AY, Nischal K, Fung SS. Vernal keratoconjunctivitis in adults: A narrative review of prevalence, pathogenesis, and management. Front Ophthalmol. 2024;4. 10.3389/fopht.2024.1328953 . Leonardi A, Busca F, Motterle L, Cavarzeran F, Fregona IA, Plebani M, et al. Case series of 406 vernal keratoconjunctivitis patients: A demographic and epidemiological study. Acta Ophthalmol Scand. 2006;84(3):406–10. 10.1111/j.1600-0420.2005.00622.x . Vichyanond P, Pacharn P, Pleyer U, Leonardi A. Vernal keratoconjunctivitis: A severe allergic eye disease with remodeling changes. Pediatr Allergy Immunol. 2014;25(4):314–22. 10.1111/pai.12197 . Brindisi G, Cinicola B, Anania C, De Castro G, Nebbioso M, Del Miraglia M et al. Vernal Keratoconjunctivitis: State of art and update on treatment [Internet]. U.S. National Library of Medicine; 2021 [cited 2025 Dec 7]. Available from: https://pubmed.ncbi.nlm.nih.gov/34842588/ Sacchetti M, Plateroti R, Bruscolini A, Giustolisi R, Marenco M. Understanding vernal keratoconjunctivitis: Beyond allergic mechanisms. Life 2021 Sept 26;11(10):1012. 10.3390/life11101012 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 06 Apr, 2026 Read the published version in Allergy, Asthma & Clinical Immunology → Version 1 posted Editorial decision: Revision requested 02 Mar, 2026 Reviews received at journal 24 Feb, 2026 Reviewers agreed at journal 19 Feb, 2026 Reviews received at journal 19 Feb, 2026 Reviewers agreed at journal 12 Jan, 2026 Reviewers invited by journal 12 Jan, 2026 Editor assigned by journal 10 Dec, 2025 Submission checks completed at journal 10 Dec, 2025 First submitted to journal 07 Dec, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8303091","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":573473109,"identity":"b39184db-d149-4b4d-9eab-acc5ec631918","order_by":0,"name":"Lauren Wong","email":"","orcid":"","institution":"Western University","correspondingAuthor":false,"prefix":"","firstName":"Lauren","middleName":"","lastName":"Wong","suffix":""},{"id":573473110,"identity":"7f1800ec-6439-48d9-8c51-3aefbc67e382","order_by":1,"name":"Samira 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01:05:33","extension":"xml","order_by":6,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":29235,"visible":true,"origin":"","legend":"","description":"","filename":"9726ce2e1c1d4f02bb4b9da0d45303231structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-8303091/v1/462c836dfad5919b71fdb98f.xml"},{"id":101099206,"identity":"56c5ca50-a353-4f51-8973-a7bde002bd48","added_by":"auto","created_at":"2026-01-26 01:05:33","extension":"html","order_by":7,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":36822,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-8303091/v1/73d4f26af0494589f2e04ed3.html"},{"id":101099202,"identity":"bc027efe-d21e-432d-ae27-1bbbafe4d613","added_by":"auto","created_at":"2026-01-26 01:05:33","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":512572,"visible":true,"origin":"","legend":"\u003cp\u003eAn 11-year-old male with vernal keratoconjunctivitis (VKC), showing conjunctival erythema (A), ecchymosis (B), chemosis (C), and possible Horner-Trantas dots (D).\u003c/p\u003e","description":"","filename":"Figure1VKC.png","url":"https://assets-eu.researchsquare.com/files/rs-8303091/v1/98f8d26fdaa05cd2398787b7.png"},{"id":106808737,"identity":"607b5c4c-f919-4135-82c6-fecbf58f908b","added_by":"auto","created_at":"2026-04-13 15:59:43","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1091574,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8303091/v1/c94d3072-0adb-4665-8022-1f03586bd95d.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"A red-eye presentation concerning for vernal keratoconjunctivitis: a case report","fulltext":[{"header":"Background","content":"\u003cp\u003eVKC is a rare allergic inflammatory disease that affects the ocular conjunctiva and cornea. It is thought to be caused by allergen exposure that triggers mast cell activation in conjunctival tissue.\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e Eosinophils have also been implicated, making up the majority of conjunctival secretions in these patients.\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e It most commonly affects males in early to mid-childhood living in hot and dry climates such as the Mediterranean, Middle East, and Central and South America where there is high dust and sunlight exposure.\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e,\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e A positive family history of allergic disease is present in 40\u0026ndash;50% of cases, and personal history of atopy including asthma, eczema, or rhinitis is present in about 46% of cases.\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eVKC is classically characterized by bilateral itchy eyes, tearing, discharge, irritation, redness, and photophobia.\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e Episodes are often recurrent with peak incidence in the spring or summer seasons, and the potential to become perennial.\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eHere we present a case of VKC in Canada with chronic symptoms that developed outside of typical seasonal patterns, with no clear provoking allergen.\u003c/p\u003e"},{"header":"Case presentation","content":"\u003cp\u003eAn 11-year-old male presented to the Allergy and Immunology clinic with a six-month history of bilateral redness and swelling of the conjunctiva. He had experienced seasonal nasal and palatal itch and sneezing from May to October for the last 3–4 years but had no known atopic history other than resolved preschool asthma.\u003c/p\u003e \u003cp\u003eThe initial onset of symptoms was in February, however in May of the presenting year he began noticing vision changes and perilimbal white dots. Review of systems was otherwise unremarkable. He tried multiple eyedrops, only experiencing relief with olopatadine (Pataday) eyedrops. Following optometry assessment, he switched to loteprednol steroid eyedrops (Lotemax). He had full resolution of symptoms on Lotemax but flared when attempting to taper off it. He was still using Lotemax, in addition to Omnaris and Aerius as needed at the time of allergy consultation.\u003c/p\u003e \u003cp\u003eOn physical exam, there were no significant findings other than internal nasal changes characteristic of allergic rhinitis. However, photos from one month prior demonstrated significant conjunctival erythema, ecchymosis, and possible Horner-Trantas dots \u003cb\u003e(\u003c/b\u003eFig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e\u003cb\u003e)\u003c/b\u003e. Skin prick testing was positive to cat dander. Serum IgE was ordered for a broad aeroallergen panel that may not have appeared positive on skin prick due to young age, with only cat returning mildly elevated.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe patient initially flared without any clear cat or other significant environmental allergen exposures in February, although based on clinical history and photos during flares, the diagnosis of vernal keratoconjunctivitis (VKC) was made. The cat dander antigen is known to be adherent and persistent nature. It is possible the patient had a large prior contact with cat, and continued exposure to lingering antigen. Atopic keratoconjunctivitis and giant papillary conjunctivitis were also considered. He was advised to restart Pataday eyedrops to facilitate a taper off the Lotemax, and to use rupatadine orally as needed for both ocular and nasal allergic symptoms.\u003c/p\u003e \u003cp\u003eHe was referred to ophthalmology for consideration of alternate management options, given the impacts of his keratoconjunctivitis on his quality of life. When he was seen, he had been off Lotemax eyedrops for one month, with improvement in ocular symptoms. No changes were made to his treatment plan as he was in low disease activity.\u003c/p\u003e \u003cp\u003eHe remained stable off Lotemax with no major flares, though continued to have minor conjunctival erythema while on Pataday one drop daily and Rupall 5 mL liquid daily. His Rupall was adjusted from liquid to tablet form and increased to 10 mg oral daily with flexibility to titrate to 40 mg daily. He also continued to use Pataday once daily. The patient remained on this regimen for one year, with no new ocular symptoms. Repeat skin testing did not reveal additional environmental allergens. Within seven months he had completely discontinued antihistamine use, with only intermittent pruritus of the eyes and mild daily conjunctivitis that was not bothersome to him. Prescriptions for oral and topical antihistamines were renewed should his vernal keratoconjunctivitis flare again, and follow-up was left open.\u003c/p\u003e "},{"header":"Discussion and Conclusions","content":"\u003cp\u003eAlthough the diagnosis of VKC should take into account the history of presenting illness, ocular examination, and investigations, it is largely clinical. Two forms of VKC exist: tarsal which involves the upper tarsal conjunctiva, and limbal which involves the bulbar conjunctiva.\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e,\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e In the tarsal form, there may be erythematous and thickened eyelids and papillae on the upper tarsal conjunctiva with a cobblestone appearance.\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e,\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e Main findings in the limbal form are gelatinous infiltrations around the limbus surrounding the cornea (Horner-Trantas dots), which are focal collections of degenerated eosinophils and epithelial cells.\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e The mixed form has features of both. In this case, the photographic identification of Horner-Trantas dots strongly aided in the clinical diagnosis of VKC. Corneal involvement can also occur in cases where VKC is not adequately or promptly treated, which is why ophthalmology involvement can be important.\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e It will initially present as punctate epithelial erosions with progression to macro erosions and ulcers, causing gradual vision loss.\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eDifferential diagnoses include other subtypes of allergic conjunctivitis such as seasonal allergic conjunctivitis, perennial allergic conjunctivitis, atopic keratoconjunctivitis, and giant papillary conjunctivitis.\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e VKC should be suspected when there is failure of treatment with common topical or systemic antihistamines traditionally used in allergic conjunctivitis.\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e Symptoms such as photophobia and ocular pain are more specific for VKC.\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e Not all VKC patients will have positive skin prick tests, and the presentation or flares of the disease are not always associated with large environmental allergen exposure.\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e,\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e This case presented an example of VKC manifesting without positive initial or repeat skin prick tests, and no clear allergen trigger. Approximately 50% of patients with VKC have a negative allergy test, as other non-IgE mechanisms are implicated in the inflammatory reaction of VKC.\u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eTreatment is a stepwise approach, with the most important step being the removal of any possible allergens in the patient’s environment.\u003csup\u003e\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e–\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e Conservative management for ocular itching, burning, and irritation includes cold compresses and saline rinses.\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e Antihistamine or mast cell stabilizer eyedrops, or dual acting agents with both, can be added.\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e Olopatadine topical antihistamine eyedrops are commonly used to target the H1 receptors.\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e Corticosteroid eyedrops such as loteprednol and fluorometholone are effective in disease flares, but are not to be used for long-term management.\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e Ideally steroids are used as pulse therapy with a taper in addition to antihistamine or mast cell stabilizers as maintenance therapy, as was done in this case. In more severe disease with persistent inflammation, macropapillae, and ulcers or macro erosions, topical immunomodulators like cyclosporine and tacrolimus may be considered.\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e Generally, VKC is a self-limiting disease with spontaneous resolution around puberty.\u003csup\u003e\u003cspan additionalcitationids=\"CR3 CR4 CR5\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e–\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eVKC\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eVernal keratoconjunctivitis\u003c/p\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConsent form obtained. Please request if a copy is required.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo sources of funding to declare.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSJ was the physician in charge of the clinical care of the patient described in the case report. SJ obtained informed consent and sourced clinical images from the patient and guardian. LW edited the clinical images. SJ and LW were responsible for drafting of the text and both read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFootnotes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eDoan S, Papadopoulos NG, Lee JK, Leonardi S, Manti S, Lau S et al. Vernal Keratoconjunctivitis: Current immunological and clinical evidence and the potential role of omalizumab [Internet]. U.S. National Library of Medicine; 2023 [cited 2025 Dec 7]. Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://pmc.ncbi.nlm.nih.gov/articles/PMC10300397/\u003c/span\u003e\u003cspan address=\"https://pmc.ncbi.nlm.nih.gov/articles/PMC10300397/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDi Zazzo A, Zhu AY, Nischal K, Fung SS. Vernal keratoconjunctivitis in adults: A narrative review of prevalence, pathogenesis, and management. Front Ophthalmol. 2024;4. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3389/fopht.2024.1328953\u003c/span\u003e\u003cspan address=\"10.3389/fopht.2024.1328953\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLeonardi A, Busca F, Motterle L, Cavarzeran F, Fregona IA, Plebani M, et al. Case series of 406 vernal keratoconjunctivitis patients: A demographic and epidemiological study. Acta Ophthalmol Scand. 2006;84(3):406\u0026ndash;10. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1111/j.1600-0420.2005.00622.x\u003c/span\u003e\u003cspan address=\"10.1111/j.1600-0420.2005.00622.x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVichyanond P, Pacharn P, Pleyer U, Leonardi A. Vernal keratoconjunctivitis: A severe allergic eye disease with remodeling changes. Pediatr Allergy Immunol. 2014;25(4):314\u0026ndash;22. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1111/pai.12197\u003c/span\u003e\u003cspan address=\"10.1111/pai.12197\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBrindisi G, Cinicola B, Anania C, De Castro G, Nebbioso M, Del Miraglia M et al. Vernal Keratoconjunctivitis: State of art and update on treatment [Internet]. U.S. National Library of Medicine; 2021 [cited 2025 Dec 7]. Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://pubmed.ncbi.nlm.nih.gov/34842588/\u003c/span\u003e\u003cspan address=\"https://pubmed.ncbi.nlm.nih.gov/34842588/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSacchetti M, Plateroti R, Bruscolini A, Giustolisi R, Marenco M. Understanding vernal keratoconjunctivitis: Beyond allergic mechanisms. Life 2021 Sept 26;11(10):1012. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3390/life11101012\u003c/span\u003e\u003cspan address=\"10.3390/life11101012\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"allergy-asthma-and-clinical-immunology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"aaci","sideBox":"Learn more about [Allergy, Asthma \u0026 Clinical Immunology](http://aacijournal.biomedcentral.com/)","snPcode":"13223","submissionUrl":"https://submission.nature.com/new-submission/13223/3","title":"Allergy, Asthma \u0026 Clinical Immunology","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"conjunctivitis, vernal keratoconjunctivitis, red eye","lastPublishedDoi":"10.21203/rs.3.rs-8303091/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8303091/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eVernal keratoconjunctivitis (VKC) is a chronic, recurrent, and seasonally exacerbated allergic eye disease that can significantly impair quality of life in children. It is a rare disease, with higher prevalence in hot and dry climates. There is a broad differential for a red eye presentation, and the diagnosis of VKC may be complicated when symptoms occur outside typical seasonal patterns or when allergy testing is unclear. We present a case of VKC in Canada, identified on allergy consultation after persistent unresponsiveness to antihistamine treatment.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCase presentation:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAn 11-year-old male presented with a six-month history of bilateral conjunctival redness and swelling, accompanied by seasonal nasal and palatal itch and sneezing. Initial symptoms began atypically in February, later progressing to photophobia and early vision changes. Clinical images showed striking perilimbal Horner-Trantas dots and marked conjunctival inflammation, ecchymosis, and chemosis. Skin prick testing and serum IgE revealed only mild sensitization to cat dander. Multiple topical therapies were trialed; symptoms improved with olopatadine and fully resolved with loteprednol, though attempts to taper the steroid resulted in recurrence. Given clinical features and photographic evidence, VKC was diagnosed, with consideration that persistent environmental cat antigen exposure may have contributed to symptom chronicity. Atopic keratoconjunctivitis and giant papillary conjunctivitis were on the differential but felt to be less likely.\u003c/p\u003e\n\u003cp\u003eThe patient was transitioned back to olopatadine to facilitate discontinuation of loteprednol, and was treated with rupatadine for ocular and nasal symptoms. Ophthalmology assessment occurred after he had been off topical steroids for one month, at which time symptoms were minimal and no further suggestions made. Over the following year, he remained stable on daily Pataday and oral rupatadine, ultimately discontinuing antihistamines entirely with only mild intermittent ocular pruritus and conjunctivitis. Repeat skin testing was unremarkable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eVKC is uncommon in Canada, but missing it has serious consequences including progressive vision loss. This case highlights VKC in an 11-year-old boy who was repeatedly treated for presumed allergic conjunctivitis despite photophobia and early vision changes. His symptoms presented outside of typical seasonal patterns, with no clear provoking allergen. Successful long-term symptom control was achieved through careful tapering of topical steroids combined with targeted antihistamine therapy.\u003c/p\u003e\n\u003cp\u003eVKC should be considered in cases of conjunctivitis unresponsive to antihistamine therapy, and is important to differentiate from other forms of allergic conjunctivitis to avoid possibly permanent ocular sequelae. A positive skin prick test or serum IgE is not necessary for the diagnosis of VKC. The exact allergen may not be known. Topical and oral antihistamine combination is effective in stabilizing VKC symptoms, with the addition of topical steroids if needed for flares. VKC treatment can require a prolonged course. Referral to ophthalmology for VKC may be considered when vision changes are involved.\u003c/p\u003e","manuscriptTitle":"A red-eye presentation concerning for vernal keratoconjunctivitis: a case report","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-26 01:05:24","doi":"10.21203/rs.3.rs-8303091/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-02T18:35:19+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-25T01:37:21+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"49394043790763676330242625989092469001","date":"2026-02-20T01:56:50+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-19T14:52:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"234898251700217369122887893245871671611","date":"2026-01-12T18:35:59+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-12T18:30:54+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-12-10T11:19:42+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-12-10T11:17:41+00:00","index":"","fulltext":""},{"type":"submitted","content":"Allergy, Asthma \u0026 Clinical Immunology","date":"2025-12-08T03:10:39+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"allergy-asthma-and-clinical-immunology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"aaci","sideBox":"Learn more about [Allergy, Asthma \u0026 Clinical Immunology](http://aacijournal.biomedcentral.com/)","snPcode":"13223","submissionUrl":"https://submission.nature.com/new-submission/13223/3","title":"Allergy, Asthma \u0026 Clinical Immunology","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"257b3ef6-fec9-4d08-9672-4c3a2a8deca0","owner":[],"postedDate":"January 26th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-04-13T15:59:37+00:00","versionOfRecord":{"articleIdentity":"rs-8303091","link":"https://doi.org/10.1186/s13223-026-01029-x","journal":{"identity":"allergy-asthma-and-clinical-immunology","isVorOnly":false,"title":"Allergy, Asthma \u0026 Clinical Immunology"},"publishedOn":"2026-04-06 15:56:59","publishedOnDateReadable":"April 6th, 2026"},"versionCreatedAt":"2026-01-26 01:05:24","video":"","vorDoi":"10.1186/s13223-026-01029-x","vorDoiUrl":"https://doi.org/10.1186/s13223-026-01029-x","workflowStages":[]},"version":"v1","identity":"rs-8303091","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8303091","identity":"rs-8303091","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}