Anterior Segment
Phlyctenular Keratoconjunctivitis
Also known as: phlyctenulis, phlyctenule, limbal nodule, corneal phlycten, staphylococcal hypersensitivity, TB conjunctivitis, phlyctenular disease, scrofulous ophthalmia
Filed as: Soon
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 delayed hypersensitivity reaction (Type IV) of the conjunctiva or cornea to microbial antigens. Classically associated with Mycobacterium tuberculosis antigens in endemic regions; in developed countries most commonly triggered by Staphylococcal antigens from blepharitis. A phlycten (small, raised, nodular lesion) typically appears at the limbus and can migrate onto the cornea, causing photophobia, corneal scarring, and vascularisation.
Recognition
Symptoms: what patients report
- Photophobia — often the dominant and most distressing symptom, especially when the cornea is involved.
- Lacrimation and blepharospasm.
- Redness, localised initially around the phlycten.
- Foreign-body sensation.
- Reduced vision if the phlycten migrates onto the visual axis.
- History of recurrent episodes — the disease tends to recur.
Signs: what the examination shows
- Phlycten: a small (1–3mm), pink-white, elevated nodular lesion at the limbus or on the conjunctiva.
- In limbal phlyctenulosis: the lesion sits at the corneoscleral junction, surrounded by dilated vessels.
- In corneal phlyctenulosis: the phlycten migrates from the limbus toward the corneal centre, dragging a leash of vessels behind it (progressive corneal phlyctenulosis).
- Corneal scarring at the site of a healed phlycten.
- Corneal vascularisation in recurrent or advanced disease.
- Associated posterior blepharitis and lid margin disease (staphylococcal aetiology).
What OptoGuide™ covers for phlyctenular keratoconjunctivitis
- 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
- Phlyctenular Keratoconjunctivitis — EyeWiki
- Anterior Eye Disease and Therapeutics A-Z (Bruce & Loughnan) — standard reference text
- Definition and Diagnostic Criteria for Pediatric Blepharokeratoconjunctivitis. Morales-Mancillas NR, Velazquez-Valenzuela F, Kinoshita S, et al. JAMA Ophthalmology. 2024;142(1):39-47.
- Peripheral Ulcerative Keratitis: Pathogenesis, Diagnosis, and Multimodal Management. Guerrero-Acosta JC, Ortiz-Morales G, Vera-Duarte GR, et al. Journal of Clinical Medicine. 2026;15(3):1264.
- Guide to Utilization of the Microbiology Laboratory for Diagnosis of Infectious Diseases: 2024 Update by the Infectious Diseases Society of America (IDSA) and the American Society for Microbiology (ASM). Miller JM, Binni
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.