Keratitis (marginal)

The CMGs are guidelines on the diagnosis and management of a range of common and rare, but important, eye conditions that present with varying frequency in primary and first contact care.

Share options

Keratitis (marginal)







Please login to view the image or join the College today.


Toxic or hypersensitivity response to bacterial (e.g. Staphylococcal) exotoxins

Predisposing factors

Bacterial (e.g. Staphylococcal) blepharitis
Current or recent upper respiratory tract infection
Condition tends to be recurrent


Ocular discomfort increasing to pain
Red eye


Ulcer (stromal infiltrate with overlying epithelial loss) which may be round or arcuate, single or multiple, unilateral or bilateral, adjacent to limbus, and separated from limbus by interval of clear cornea
Ulcer stains with fluorescein
Hyperaemia and oedema of adjacent bulbar conjunctiva

Differential diagnosis

Other causes of ulceration of the peripheral cornea:

  • microbial keratitis
  • contact lens-associated corneal infiltrate
  • rosacea keratitis
  • Mooren’s ulcer
  • peripheral keratitis associated with rheumatoid arthritis or other systemic collagen vascular disease
  • corneal phlyctenulosis
  • Terrien’s marginal degeneration
  • marginal herpes simplex keratitis

Management by optometrist

Practitioners should recognise their limitations and where necessary seek further advice or refer the patient elsewhere

Non pharmacological

Sunglasses to ease photophobia
(GRADE*: Level of evidence=low, Strength of recommendation=strong)


Ocular lubricants for symptomatic relief (drops for use during the day, unmedicated ointment for use at bedtime)
Systemic analgesia if needed: paracetamol, aspirin or ibuprofen
Regular lid hygiene for associated blepharitis (with a view to limiting recurrence)
(GRADE*: Level of evidence=low, Strength of recommendation=strong)

Marginal keratitis is a self-limiting condition. Nevertheless it is conventional to give pharmacological treatment with a view to relieving symptoms and shortening the clinical course. However, this practice is not supported by evidence from clinical trials

The concurrent use of topical antibiotic (e.g. gutt chloramphenicol 0.5% qds) to reduce bacterial load, in addition to topical steroid (e.g. gutt prednisolone sodium phosphate 0.5%.qds for a week, then bd for a week) to reduce inflammation, is theoretically justified. However, the immunosuppressive effect of the steroid enhances the risk of infection
(GRADE*: Level of evidence=low, Strength of recommendation=weak)

Management category

B3: management to resolution
If persistent or recurrent, refer to ophthalmologist

Possible management by ophthalmologist

Microbiological cultures of lesion and lid margins
Investigation of patient’s immune status

Evidence base

*GRADE: Grading of Recommendations Assessment, Development and Evaluation (

Sources of evidence

Chignell AH, Easty DL, Chesterton JR, Thomsitt J. Marginal ulceration of the cornea. Brit J Ophthalmol 1970;54:433-40

Ficker L, Seal D, Wright P. Staphylococcal infection and the limbus: study of the cell-mediated immune response. Eye (Lond). 1989;3 ( Pt 2):190-3

Plain language summary

This is a slightly unusual condition caused by a reaction to the presence of bacteria (germs) near the eye, for example on the edges of the eyelids. It is an inflammation, not an infection. Patients experience redness, watering and pain in the eye. A shallow ulcer develops at the edge of the cornea (the clear window of the eye), which can resemble a number of other conditions including infection. The condition usually resolves by itself, but it may be dealt with more quickly if steroid and antibiotic drops are prescribed. If blepharitis (inflammation of the edges of the eyelids) is the cause, this should be treated.

Keratitis (marginal)
Version 11
Date of search 24.05.19
Date of revision 29.05.19
Date of publication 22.03.21
Date for review 23.05.21
© College of Optometrists 

View more Clinical Management Guidelines