Cornea
Fungal Keratitis
Also known as: fungal keratitis, mycotic keratitis, Fusarium keratitis, Aspergillus keratitis, Candida keratitis, fungal corneal ulcer, mould keratitis, filamentary fungal keratitis
Filed as: Emergency
Source-cited from the record's own evidence list. Clinical content programme led by Dr Ankit Mathur, PhD, Grad Cert Ocu Thera, B.S. Optom. How the clinical content is governed
Clinical decision support only
Overview
Corneal infection by fungi — either filamentary (Fusarium, Aspergillus — typically following vegetative trauma or topical steroid use) or yeast (Candida — typically in immunocompromised or chronically diseased corneas). A rare but severe cause of infectious keratitis with high rates of corneal melt and perforation. Often misdiagnosed as bacterial keratitis or HSV stromal keratitis. Topical and systemic antifungal therapy is required under specialist supervision.
Recognition
Symptoms: what patients report
- Eye pain — moderate to severe.
- Redness.
- Photophobia.
- Tearing.
- Blurred vision.
- History of: vegetative or organic trauma to the cornea (branch, leaf, soil), topical steroid use, contact lens wear, or immunocompromised state.
- Slow, progressive onset over days to weeks — often slower than bacterial keratitis.
Signs: what the examination shows
- Corneal infiltrate with characteristic features:
- Filamentary fungi (Fusarium, Aspergillus): dry, raised, rough or necrotic infiltrate with feathery/irregular branching edges; satellite lesions.
- Coloured infiltrates other than yellow can occur and should prompt fungal consideration.
- Endothelial or immune ring may be present.
- Often little or no significant discharge compared with bacterial ulcer.
- Yeast (Candida): creamy white infiltrate with defined borders — more similar to bacterial keratitis in appearance.
- Satellite infiltrates around the main lesion — a highly suggestive feature.
- Immune ring (Wessely ring) around the infiltrate.
- Hypopyon — may be visible.
- Stromal inflammation and oedema.
- Epithelial defect over the infiltrate.
What OptoGuide™ covers for fungal keratitis
- Pattern reasoning: what this combination of findings points to, and its differentiators
- Don't-miss risks and escalation triggers
- Management tiers with linked Australian therapeutics
- Referral urgency, specialty, and letter drafting
Sources
- Fungal Keratitis — EyeWiki
- Microbial keratitis (bacterial, fungal) — College of Optometrists CMG
- Anterior Eye Disease and Therapeutics A-Z (Bruce & Loughnan) — standard reference text
- Infectious Keratitis in 2021. Durand ML, Barshak MB, Chodosh J. JAMA. 2021;326(13):1319-1320.
- The Global Incidence and Diagnosis of Fungal Keratitis. Brown L, Leck AK, Gichangi M, Burton MJ, Denning DW. The Lancet. Infectious Diseases. 2021;21(3):e49-e57.
- Differentiation of acanthamoeba keratitis from other non-acanthamoeba keratitis: Risk factors and clinical features. Alreshidi SO, Vargas JM, Ahmad K, et al. PloS One. 2024;19(3):e0299492.
Standard texts: Kanski's Clinical Ophthalmology: A Systematic Approach, The Wills Eye Manual, Oxford Handbook of Ophthalmology, Oxford American Handbook of Ophthalmology, Signs in Ophthalmology: Causes & Differential Diagnosis.