Specimen Required

Tissue in sterile container

Specimen Minimum Volume

If tissue is detectable, it can be accepted for culture. Specimens too large to fit inside a sterile urine container are accepted, but reported with a warning comment if the specimen is received in a non-sterile container.

Warning comment: “Precious specimen received in a non-sterile container. Growth may represent environmental contamination.”

Transport Temperature

Reject Due To

Useful For

Identification and susceptibility of bacteria causing invasive infections of skin, muscle, bone, joint or other human tissues.

Clinical Information

Invasive bacterial infections of tissues include necrotizing fasciitis, surgical wound infections, diabetic foot infections, osteomyelitis, endocarditis and septic arthritis. These infections require surgery for source control.  During surgery, tissue is collected to allow identification and susceptibility testing of bacteria.  This tissue is a precious specimen since it is collected surgically, and contains large numbers of bacteria which are protected during transportation by the tissue structure.  Tissue specimens should be cultured for aerobes and anaerobes, and may require prolonged incubation including broth incubation.  Generally speaking, growth of any bacteria will be considered pathogenic, however, if tissue is necrotic, growth may represent flora.

Testing Algorithm

Tissue is applied to multiple selective and non-selective media and incubated aerobically and anaerobically, in order to optimize growth of all organisms present. All organisms detected will be identified with susceptibility, according to the microbiologist’s assessment.

Reference Values

1. No growth

Interpretation

Identification and susceptibility provided according to cascade policy.  Interpretive comments may be added.

Clinical Reference

Garcia, L. (Ed.). (2010). Clinical Microbiology Procedures Handbook, 3^rd Edition. Washington, DC: ASM Press.

Method Description

1. Tissue is macerated if appropriate
2. Tissue is applied to selective and non-selective media and broth
3. Media are incubated aerobically and anaerobically at 35°C for 48 hours. Broth are incubated for seven days at 35°C.
4. Bacterial growth is identified.