Bacteria - Culture & Sensitivities – Eye/Ear
| C&S Ear/Eye | |
| Microbiology | |
| Bacteriology | |
| ○ Corneal scrapings ○ Conjunctival swab ○ Eye swab ○ Lacrimal stone/secretions ○ External ear swab ○ Ear/eye devices |
Culture-based detection of bacterial pathogens in non-sterile ear and eye specimens
○ Corneal scrapes: ideally,agar plates (blood, chocolate [and IMA if fungal culture is being ordered]), thioglycollate broth and microscope slide (contact the microbiology laboratory to obtain collection supplies). Sterile container with small amount of sterile saline is an alternative.
○ Swabs: Sterile swab in Amies transport medium (eSwab)
○ Lacrimal stone/secretions or devices: Clean, sterile container
○ Swabs: Sterile swab in Amies transport medium (eSwab)
○ Lacrimal stone/secretions or devices: Clean, sterile container
Corneal Scrapes:
Preferably plant at bedside onto agars (BA, CHOC, IMA), into broth (THIO), and onto microscope slide; otherwise collect in sterile container with small amount of sterile saline. Corneal surfaces should be rinsed thoroughly with sterile normal saline to remove anaesthetic prior to collecting specimen; use a Kimura scalpel to scrape across the ulcer using short firm strokes in one direction; obtain 3 to 5 scrapings per cornea. Avoid contact with eyelids/eyelashes. For agar, plant in rows of C-shaped marks, with each row representing a separate sample.
Conjunctival/eye swab:
○ Conjunctival surfaces should be rinsed thoroughly with normal saline to remove anaesthetic prior to collecting specimen. Roll a sterile pre-moistened swab over the conjunctiva and place in transport medium.
○ Collect samples from both affected and unaffected eyes to compare microbial growth using different swabs/transport media for each eye. Swabs should be collected prior to the instillation of topical anaesthetics or antibiotics.
Lacrimal stone/secretions:
○ For lacrimal stones, collect stones using sterile technique and place into sterile container.
○ For lacrimal secretions, collect visible purulent discharge using a swab or press lacrimal sac to remove exudate for culture. Do not perform a needle aspiration of the lacrimal gland.
External ear swab:
○ Insert clean, sterile swab into ear canal until resistance is met. Rotate swab to collect fluid on swab and place in transport medium.
○ If ear drum is ruptured, collect exudate on swab after inserting through an auditory speculum
Devices:
○ Collect device and place in sterile container using aseptic technique where possible to avoid contamination
Preferably plant at bedside onto agars (BA, CHOC, IMA), into broth (THIO), and onto microscope slide; otherwise collect in sterile container with small amount of sterile saline. Corneal surfaces should be rinsed thoroughly with sterile normal saline to remove anaesthetic prior to collecting specimen; use a Kimura scalpel to scrape across the ulcer using short firm strokes in one direction; obtain 3 to 5 scrapings per cornea. Avoid contact with eyelids/eyelashes. For agar, plant in rows of C-shaped marks, with each row representing a separate sample.
Conjunctival/eye swab:
○ Conjunctival surfaces should be rinsed thoroughly with normal saline to remove anaesthetic prior to collecting specimen. Roll a sterile pre-moistened swab over the conjunctiva and place in transport medium.
○ Collect samples from both affected and unaffected eyes to compare microbial growth using different swabs/transport media for each eye. Swabs should be collected prior to the instillation of topical anaesthetics or antibiotics.
Lacrimal stone/secretions:
○ For lacrimal stones, collect stones using sterile technique and place into sterile container.
○ For lacrimal secretions, collect visible purulent discharge using a swab or press lacrimal sac to remove exudate for culture. Do not perform a needle aspiration of the lacrimal gland.
External ear swab:
○ Insert clean, sterile swab into ear canal until resistance is met. Rotate swab to collect fluid on swab and place in transport medium.
○ If ear drum is ruptured, collect exudate on swab after inserting through an auditory speculum
Devices:
○ Collect device and place in sterile container using aseptic technique where possible to avoid contamination
Refer to section Sample Processing / Delivery
In-house
○ up to 72h
416-586-4800 extension 4432
NO
○ Label specimen container. Place specimens in biohazard bag and seal.
○ Swabs and lacrimal stones/secretions should be stored at room temperature (20-25˚C) after collection. If a delayed of more than 2h is expected, store at refrigeration temperature (2-8˚C). Transport to the UHN/SH Microbiology Laboratory ASAP after collection.
○ For inoculated plates, keep in the incubator (35˚C) before transport and processing. Transport to the UHN/SH Microbiology Laboratory ASAP after collection.
○ Swabs and lacrimal stones/secretions should be stored at room temperature (20-25˚C) after collection. If a delayed of more than 2h is expected, store at refrigeration temperature (2-8˚C). Transport to the UHN/SH Microbiology Laboratory ASAP after collection.
○ For inoculated plates, keep in the incubator (35˚C) before transport and processing. Transport to the UHN/SH Microbiology Laboratory ASAP after collection.