Tissue/Aspirate/Bone Culture-Provincial

Overview

Description

• Preferred specimen type for patients with complicated wound infections and closed abscesses
• Includes diabetic foot infections, osteomyelitis, cellulitis without open wound, necrotizing wounds, complicated post-surgical wounds and chronic recurrent wound infections.
• Wound aspirates may be taken from closed abscesses, lymph nodes, lungs, liver or bones
• Specimens often collected in operating suite or clinic
• Includes bacterial culture and gram stain

Ordering recommendations

• Collect specimen prior to antimicrobial therapy for greatest diagnostic sensitivity
• If patient is on antimicrobials, provide current antimicrobial therapy and start date
• Always provide detailed specimen source including anatomical site and specimen type, clinical history including signs, symptoms and duration
• For suspected fungal infections, submit aspirates or tissues and request fungal culture
• For suspected chronic mycobacterial cultures, submit tissue and request mycobacterial (AFB) culture

Alias

• Closed space culture
• OR culture
• Biopsy culture

Specimen Information

Specimen types accepted

• Sterile container
• Tissue may be moistened with a few drops of sterile saline to prevent drying
• Never submit tissues or aspirates in swab transport media
• Never submit aspirates in syringes
• Specimens in formalin or not suitable for culture and will be rejected

Specimen collection container

• Sterile container
• Anaerobic transport system (PRAS, BBL Port-A-Cul)

Collection procedure

• Prior to the collection of any specimen, remove all exudate, purulent material and necrotic tissue from the wound or infected tissue. Wash the wound thoroughly using normal saline.
• Wound base should be visible and free of exudate, pus and necrotic tissue before sampling.
• Collect from areas with viable not necrotic tissue.
• Specimens should be taken before antibiotic treatment. 
• Use sterile needle or sterile scalpel to collect samples under aseptic conditions.
• Sharp dissection is preferred for collection to cautery.
• Place tissue in sterile plastic container. Moisten with saline. Small tissue pieces may be covered with transport media or saline. 
• For multiple specimen collections, ensure that each specimen container has a corresponding requisition.
• For prosthetic joint infections, collect 5-6 tissues each 3-4 mm in size and do not send swabs.

Required volume

• 1 sterile container
• 0.5-1 cm diameter of tissue preferred
• 3 - 4 mm biopsy sample at minimum
• 0.5 ml of aspirate fluid

Transport and stability

• Tissue and aspirate samples can be transported at room temperature for 12 - 24 hours
• Transport refrigerated at 4°C for stability of 3 - 5 days

Performance

Days/times performed

• All specimens will be tested at the nearest microbiology laboratory

Maximum laboratory time

• Turnaround time of 24-72 hours from receipt in lab

Specimen retention time

RGH	Specimens are retained for 7 days after initial processing Tissue and fluid from sterile sites held for 1 month
RUH	Specimens are retained for 7 days after initial processing. Biopsy samples are retained for 30 days.

 

Other information

Patient History

• For complicated wound infections and surgical collections, aspirates or tissue biopsies are preferred. This includes diabetic foot infections, osteomyelitis, prosthetic joint infections, complicated post-surgical wounds, necrotizing wounds, atypical pathogens or chronic recurrent infections.

Last Updated: September 9, 2025