Eye Swab Culture

Special Precautions/Comments:

N.B. Any eye swab from a baby (<1month) should be kept at room temperature and NOT refrigerated. (Code: EYE_SW_BAB)

If viral conjunctivitis (adenovirus, herpes simplex virus, varicella-zoster virus) or chlamydial infection is suspected, these require swabs to be sent in separate appropriate transport media. Please refer to the appropriate PCR test.

Interferences:  Antibiotics may affect growth of certain bacteria.

Method:  Culture on selective media. Swabs from neonates (<1 month) will receive further culture for Neisseria gonorrhoeae as routine. Isolates will be identified where clear. Where identification is not clear a likely/possible identity will be given until additional tests can be performed to confirm identity. Significant isolates will undergo antibiotic susceptibility testing.  Calibration: N/A.  EQA scheme: NEQAS EQA scheme. IQC: Regular resubmission of anonymised patient samples.

Interpretation: Negative cultures will be reported as No growth. Mixed coliforms and skin flora will be reported as such but will not receive further identification and testing. Significant organisms will be identified and tested for antibiotic susceptibility. Unusual/unexpected results may be sent to a reference laboratory (turnaround 7-10 days). Clinical comment will be provided where appropriate.

Additional Information:

Background information:  Infections of the eye can be caused by a variety of microorganisms. Swabs from eyes may be contaminated with skin microflora, but any organism may be considered for further investigation if clinically indicated.

Exogenous organisms may be introduced to the eye via hands, fomites (e.g. contact lenses), traumatic injury, or following surgery. Haematogenous spread from a focus elsewhere in the body can also occur.

Common mild eye infections include conjunctivitis (inflammation of the conjunctiva). Conjunctivitis may occur in association with infection of the eyelid (blepharoconjunctivitis), inflammation of the eye lid (blepharitis) or of the cornea (keratoconjunctivitis). Less common and more severe infections include keratitis (inflammation of the cornea) and endophthalmitis (infection inside the eye itself). Other periocular infections include dacryoadenitis (inflammation of the lacrimal gland), dacryocystitis (inflammation of the lacrimal sac), canaliculitis (infection of the lacrimal puncta and canaliculi), and preseptal and orbital cellulitis. Hypopyon is a condition associated with a leukocytic exudate, seen in the anterior chamber of the eye, usually accompanied by redness of the conjunctiva and the underlying episclera. Please provide clinical detail if any of these conditions are suspected.

Keywords: Eye swab, culture, SEI, conjunctivitis, GC, gonorrhoea, sticky eyes