Cornea
Infectious Crystalline Keratopathy
Also known as: ICK, crystalline keratopathy, infectious keratopathy, corneal crystalline infiltrates, post-keratoplasty keratitis, branching stromal opacity, needle-like corneal opacity, intrastromal crystalline infiltrate
Filed as: Urgent
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
A rare, indolent infectious keratitis pattern with branching or needle-like crystalline stromal opacities and surprisingly little surrounding inflammation. It is classically seen in eyes with prior keratoplasty, retained or loose sutures, topical corticosteroid exposure, ocular surface compromise, neurotrophic cornea, or systemic immunosuppression. This is not routine optometry-managed microbial keratitis: suspected infectious crystalline keratopathy needs ophthalmology / cornea specialist involvement, microbiology consideration, and careful exclusion of graft infection, HSV, fungal keratitis, stromal dystrophy, and non-infectious deposits.
Recognition
Symptoms: what patients report
- Often mild or slowly progressive blur, haze, glare, irritation, tearing, or foreign-body sensation.
- Pain and redness may be less prominent than expected for an infectious keratitis because inflammation can be minimal.
- May be found during review of a graft, neurotrophic cornea, chronic epithelial defect, or steroid-treated ocular surface.
- History may include corneal transplant, loose or retained suture, topical steroid use, ocular surface disease, prior epithelial breakdown, or immunosuppression.
- Worsening pain, photophobia, discharge, or reduced vision suggests more active microbial keratitis or secondary infection.
Signs: what the examination shows
- Branching, arborising, needle-like, grey-white or crystalline stromal opacity.
- Intrastromal infiltrate with minimal conjunctival injection or surrounding inflammatory response.
- May sit near a graft-host junction, retained suture, interface, or area of previous epithelial compromise.
- Epithelial defect may be absent, small, or intermittent; fluorescein staining should still be checked carefully.
- Anterior chamber reaction is often mild or absent unless infection is more active or complicated.
- Corneal graft oedema, loose suture, epithelial defect, focal infiltrate, or hypopyon changes urgency toward graft infection / microbial keratitis.
What OptoGuide™ covers for infectious crystalline keratopathy
- 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
- Infectious Crystalline Keratopathy — EyeWiki
- Anterior Eye Disease and Therapeutics A-Z (Bruce & Loughnan) — standard reference text
- Infectious Crystalline Keratopathy. Porter AJ, Lee GA, Jun AS. Survey of Ophthalmology. 2018 Jul - Aug;63(4):480-499.
- Cytomegalovirus Induced Infectious Crystalline Keratopathy After Penetrating Keratoplasty. Atighehchian M, Jafari Z, Zarei-Ghanavati S, Sheikhghomi S, Zarei-Ghanavati M. Cornea. 2026;:00003226-990000000-01151.
- Differential Diagnosis Between Granular Corneal Dystrophy Groenouw Type I and Paraproteinemic Crystalline Keratopathy. Møller HU, Ehlers N, Bojsen-Møller M, Ridgway AE. Acta Ophthalmologica. 1993;71(4):552-5.
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.