Keratitis, CL-associated infiltrative

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.

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  • Contact lens-associated infiltrative events, including:
    • contact lens-associated peripheral ulcer (CLPU)
    • contact lens-associated infiltrative keratitis
  • The aetiology of this condition is inflammatory, not infective. Though it is bacteria-related, bacteria do not invade or replicate in the cornea and there is no progression to infection, nor is the condition a marker for increased risk of microbial keratitis, which is a separate disease entity
  • CL-associated infiltrative keratitis is considered to be a response to microbial (usually Staphylococcal) antigens, derived from bacteria on the lens or on the lid margin. Micro-organisms cannot usually be recovered from the lesions
  • Incidence of contact lens associated inflammatory events in daily disposable silicon hydrogel lenses has been reported as 0.4% per year of wear; incidence is higher in re-usable lenses and much higher in extended wear

Predisposing factors

  • Bacterial bioburden of eyelid margins, contact lenses and contact lens cases
  • Multipurpose contact lens solutions
  • Smoking
  • Poor hand hygiene


  • Eye moderately red and slightly watery
  • Mild FB sensation
  • Mild photophobia

(NB: symptoms vary in severity; some cases are asymptomatic)


  • Peripheral anterior stromal infiltrate, single or multiple
  • Usually small (generally less than 1.0mm in diameter)
  • Overlying epithelium usually stains with fluorescein
  • Conjunctival hyperaemia, mild
  • Epiphora, mild (or absent)
  • Anterior chamber quiet or mildly inflamed
  • No lid oedema
  • Usually unilateral

Differential diagnosis

  • Microbial (bacterial or fungal) keratitis
    • appearance can be similar, therefore monitor closely especially over the first 24 hours and if diagnosis remains in doubt, refer to ophthalmologist as an emergency
  • Marginal keratitis
  • Corneal scar
  • Herpes simplex keratitis
  • Adenovirus keratoconjunctivitis

Management by optometrist

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

GRADE Level of evidence and strength of recommendation always relates to the statement(s) immediately above

Non pharmacological
  • Temporarily discontinue lens wear
    • most signs and symptoms resolve within 48 hours
    • infiltrates resolve over 2-3 weeks
  • Advise against extended wear
  • Warn about possibility of recurrence
  • If condition recurs, switch to disposable CLs 
  • Lid hygiene if blepharitis present

(GRADE*: Level of evidence=low, Strength of recommendation=strong)

  • Ocular lubricants for symptomatic relief
  • Oral antibiotic (tetracycline group) may be indicated for blepharitis (see Clinical Management Guideline on Blepharitis)

(GRADE*: Level of evidence=low, Strength of recommendation=weak)

Management category

B2: alleviation / palliation: normally no referral

Possible management by ophthalmologist

Not normally referred

Evidence base

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

Sources of evidence

Chalmers RL, Hickson-Curran SB, Keay L, Gleason WJ, Albright R. Rates of adverse events with hydrogel and silicone hydrogel daily disposable lenses in a large postmarket surveillance registry: the TEMPO Registry. Invest Ophthalmol Vis Sci. 2015;56(1):654-63

Richdale K, Lam DY, Wagner H, Zimmerman AB, Kinoshita BT, Chalmers R, Sorbara L, Szczotka-Flynn L, Govindarajulu U, Mitchell GL. Case-Control Pilot Study of Soft Contact Lens Wearers With Corneal Infiltrative Events and Healthy Controls. Invest Ophthalmol Vis Sci. 2016;57(1):47-55

Sweeney DF, Jalbert I, Covey M, Sankaridurg PR, Vajdic C, Holden BA, Sharma S, Ramachandran L, Willcox MD, Rao GN. Clinical characterization of corneal infiltrative events observed with soft contact lens wear. Cornea. 2003;22:435-42

Szczotka-Flynn L, Jiang Y, Raghupathy S, Bielefeld RA, Garvey MT, Jacobs MR, Kern J, Debanne SM. Corneal inflammatory events with daily silicone hydrogel lens wear. Optom Vis Sci. 2014;91:3-12

Lay summary

This condition, affecting contact lens wearers, has been given many different names. It is an inflammation of the cornea (the clear window of the eye) caused by a reaction to bacteria on the surface of the contact lens. Patients experience slight discomfort, redness and watering of the eye (it usually affects just one eye) and they may be unduly sensitive to light. The optometrist will see a small opaque area or areas near the edge of the cornea, plus inflammation of the white of the eye.
The most important task of the optometrist is to distinguish between this condition and an actual infection of the cornea, which is a sight-threatening emergency. Stopping contact lens wear usually allows the symptoms and most of the signs to resolve within 48 hours. Patients will usually need to be reminded of contact lens hygiene measures, including hand washing before handling their lenses, the need to replace their lens case frequently and avoiding overnight wear of their lenses.

Keratitis, CL-associated infiltrative
Version 5
Date of search 20.05.17
Date of revision 20.09.17
Date of publication 05.12.17
Date for review 19.05.19
© College of Optometrists 

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