Marginal Keratitis

Question 1

Aetiology

Answer 1

Inflammation of peripheral cornea in response to bacterial staphylococcal exotoxins rather than direct inoculation

Question 2

Predisposing factors

Answer 2

Bacteria on eyelids e.g. blepharitis

Question 3

Symptoms

Answer 3

Redness
Discomfort - FB sensation increasing to pain
Watering
Photophobia

Question 4

Signs

Answer 4

Stromal infiltrate adjacent to limbus but separated by a clear interval of cornea - can be single or multiple, unilateral or bilateral, and round or arcuate

Overlying epithelial loss leading to ulcer formation, stains with NaFl

Hyperaemia of adjacent bulbar hyperaemia and limbus
Oedema of adjacent bulbar hyperaemia

Question 5

Pharmacological management

Answer 5

Ocular lubricants and ointment
Systemic analgesia for pain relief

Condition is self-limiting but treatment is justified to reduce symptoms and shorten clinical course of condition

Concurrent use of topical antibiotic and steroid for 2 weeks can reduce inflammation however immunosuppressive effects of steroid can enhance risk of infection.

Question 6

Non-pharmacological management

Answer 6

Manage blepharitis - lid hygiene routine
Sunglasses for photophobia

Question 7

Refer?

Answer 7

Not usually
If persistent or recurrent, refer onwards.