Mycobacterium – detection – Superficial abscess, lesion, wound or aspirate

Alternative Names/Synonyms	Detection of acid fast bacilli from superficial abscess, lesion, wound or aspirate
Laboratory	Microbiology
Sub-section	Bacteriology
Specimen Type	○ Abscess contents (≥ 5 mL) ○ Aspirate (≥ 5mL) ○ Biopsy (1 g of tissue) ○ Wound (≥ 5mL abscess/wound fluids) ○ Skin lesion (1 g of tissue)

Other Information

○ Wound swabs are unacceptable specimens for mycobacterial detection
○ Specimens submitted in anaerobic transport medium, in formalin, dry swabs and frozen, will not be tested
○ Indicate if specimen is from a superficial site, the source of specimen and where it was acquired. This will help the lab to provide the appropriate culture media and incubation time.

Specimen Requirements (Tube Type)

○ Sterile container (min volume 5 mL or 1 gram)

Collection Requirements

Wound aspirate
○ Decontaminate skin, collect aspirate of wound using a syringe and needle. Dispense aspirated fluid into sterile container

Biopsy/skin lesion tissue
○ Collect 5-10 mm3 tissue aseptically using surgical technique/punch biopsy. Place in a clean, sterile container with a small amount of sterile saline. Do not wrap in gauze.
○ If lesion is cutaneous, collect biopsy from periphery of lesion or aspirate material under lesion margin

Sample Stability

Refer to section Sample Processing / Delivery

Routine Turnaround Time

○ Microscopy: 1 day
○ Culture: Up to 49 days; a positive culture is reported within 24h of growth

Laboratory Contact Information

416-586-4800 extension 4570

Approval Required

Sample Processing / Delivery

○ Label specimen container. Place specimens in biohazard bag and seal.

○ Specimens should be stored at refrigeration temperature (2-8˚C) after collection if transport is delayed more than one hour. Transport to the UHN/SH Microbiology Laboratory ASAP after collection.

○ The specimen will be referred to the Public Health Ontario Laboratory for testing