Clinical use
Investigation of contact lens and intraocular fluid for infection.
Background
Keratitis is infection of the cornea. This is a serious condition requiring prompt and meticulous investigation and may progress to perforation and blindness if treatment is unsuccessful.
Initial infection with keratitis may progress to endophthalmitis if inappropriately treated. Predisposing factors include:
- contact lens wear; followed by
- pre-existing ocular disease including
- herpes simplex keratitis,
- ocular trauma,
- ocular surgery,
- laser refractive surgery
- use of topical steroids
The condition may be caused by a wide range of bacteria, fungi and parasites.
Infectious endophthalmitis is a relatively uncommon but potentially sight-threatening infection of intraocular fluids and tissue. It may develop as a result of surgery, trauma, or by haematogenous spread of organisms. The most appropriate specimens for investigation of endophthalmitis are intraocular fluids (aqueous humour from the anterior chamber and vitreous humour from the vitreous cavity/body). Eye swabs may also be taken.
Patient preparation
Any available pus should be sampled as well as the lesion of interest.
It may also be useful to sample the contact lens itself and the contact lens case, if still available, and cleaning solutions.
Separate samples must be collected into appropriate transport media for detection of viruses or chlamydia.
Specimen requirements
- Intraocular fluid / aspirates: Sterile universal
- Contact Lenses: Original contact lens case
If a swab is being used, please see the Bacteriology eSwabs user guide for appropriate swab choice and collection.
Limitations & restrictions
Collect samples prior to antibiotic therapy where possible.
Turnaround time
7 days
Analysing laboratory
Microbiology Lab, James Cook University Hospital, Marton Road, TS4 3BW
Additional information
Specimens should be transported and processed as soon as possible. If processing is delayed, refrigeration is preferable to storage at ambient temperature.
If specimens for investigation for amoebae cannot be processed within 8hr, it is preferable to store them at ambient temperature.
Do not freeze specimens.