Risk-based scoring system to assess probability of fungal etiology of keratitis
DOI: 10.32364/2311-7729-2026-26-1-1
E.V. Boiko1,2, N.V. Shchemerov1,3, O.A. Frolov3, E. Zeibel1, A.S. Sidina1, D.E. Zhumabek4, V.S. Tomazova1
1North-Western State Medical University named after I.I. Mechnikov, Moscow, Russian Federation
2St. Petersburg Branch of the S. Fyodorov Eye Microsurgery Federal State Institution, St. Petersburg, Russian Federation
3Diagnostic Center No. 7, St. Petersburg, Russian Federation
4RUDN University, Moscow, Russian Federation
Background: fungal keratitis (FK) is a severe corneal infection leading to persistent visual impairment, and it is associated with high incidence of complications including corneal perforation, endophthalmitis, secondary glaucoma, and globe loss. Often, these adverse outcomes may be caused by delayed diagnosis and untimely initiation of targeted antifungal therapy. Early recognition of FK is particularly critical for local practitioners, since a patient may lose his/her time at this stage. In turn, this may lead to the disease progression and reduced efficacy of subsequent therapy. Accurate diagnosis is often challenging due tononspecific nature of early clinical manifestations and limited availability of advanced diagnostic methods for fungal pathogen identification.
Aim: to develop a risk-based scoring system to assess probability of fungal keratitis and to evaluate its diagnostic performance.
Materials and Methods: the study was conducted in several stages: (1) a review of domestic and foreign literature to identify key risk factors and clinical features of FK; (2) a retrospective analysis of 29 medical records of patients with microbiologically confirmed fungal keratitis to determine diagnostic value of each criterion; and (3) a comparative analysis with a control group (33 patients with non-fungal keratitis) including significance calculation. Diagnostic features were evaluated with a scoring system.
Results: a risk-based scoring system including a set of anamnestic and clinical criteria (such as symptom duration, contact lens–related disease, lack of response to standard therapy, and specific corneal changes) was developed. Each criterion had individual diagnostic value. A threshold value of 16 points was identified; scores exceeding this threshold demonstrated a sensitivity of 95% for FK diagnosis as compared with the control group.
Conclusion: the proposed scoring system may serve as an effective preliminary diagnostic tool enabling timely and evidence-based suspicion of fungal keratitis, as well as appropriate referral for additional specific screening to minimize risks of delayed diagnosis and complications.
Keywords: fungal keratitis; keratomycosis; ophthalmomycosis; risk-based scoring system; risk factors; diagnosis; clinical signs; medical history; ocular trauma; contact lenses; corneal infiltrate; ocular surface diseases.
For citation: Boiko E.V., Shchemerov N.V., Frolov O.A., Zeibel E., Sidina A.S., Zhumabek D.E., Tomazova V.S. Risk-based scoring system to assess probability of fungal etiology of keratitis. Russian Journal of Clinical Ophthalmology. 2026;26(1):2–9 (in Russ.). DOI: 10.32364/2311-7729-2026-26-1-1
About the authors:
Ernest V. Boiko — Dr. Sc. (Med.), Professor, Head of the Department of Ophthalmology, North Western State Medical University named after I.I. Mechnikov; 41, Kirochnaya str., St. Petersburg, 191015, Russian Federation; Director of the St. Petersburg Branch of S. Fyodorov Eye Microsurgery Federal State Institution; 21, Yaroslav Gashek str., St. Petersburg, 192283, Russian Federation; ORCID iD 0000-0002-7413-7478
Nikolai V. Shchemerov — Postgraduate Student at the Department of Ophthalmology, North Western State Medical University named after I.I. Mechnikov; 41, Kirochnaya str., St. Petersburg, 191015, Russian Federation; ORCID iD 0000-0002-9874-6665
Oleg A. Frolov — Chief Physician of Ophthalmologiocal Pediatric and Adult Diagnostic Center No. 7; 38, Mokhovaya st., St. Petersburg, 191028, Russian Federation; ORCID iD 0000-0002-0162-5454
Emma Zeibel — 2nd-year Clinical Resident at the Department of Ophthalmology, North Western State Medical University named after I.I. Mechnikov; 41, Kirochnaya str., St. Petersburg, 191015, Russian Federation; ORCID iD 0009-0004-7754-7976
Anastasia S. Sidina — 1st-year Clinical Resident at the Department of Ophthalmology, North Western State Medical University named after I.I.Mechnikov; 41, Kirochnaya str., St. Petersburg, 191015, Russian Federation; ORCID iD 0009-0000-7720-7737
Dauren E. Zhumabek — 2nd-year Clinical Resident at the Department of Eye Diseases, RUDN University; 6, Miklukho-Maklaya str., Moscow, 117198, Russian Federation; ORCID iD 0000-0001-7298-3999
Veronika S. Tomazova — 5th-year Student at the Faculty of General Medicin, North Western State Medical University named after I.I. Mechnikov; 41, Kirochnaya str., St. Petersburg, 191015, Russian Federation; ORCID iD 0009-0007-9672-8010
Contact information: Nikolai V. Shchemerov, e-mail: shemerovvv@gmail.com
Financial Disclosure: no authors have a financial or property interest in any material or method mentioned.
There is no conflict of interest.
Received 10.02.2026.
Revised 11.02.2026.
Accepted 11.02.2026.
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