Culture - bone marrow
This is a laboratory test performed on a bone marrow specimen to isolate and identify organisms that cause infection.
How the test is performed
A bone marrow biopsy or aspirate is performed (see bone marrow biopsy and bone marrow aspiration articles). A sample of bone marrow is placed on culture media in containers for the purpose of growing microorganisms (bacteria, fungus, or viruses) in the laboratory. Microorganisms that grow will later be identified under the microscope.
The microbiologist in the laboratory inspects the cultures daily for growth of organisms. If microorganisms are detected, other tests may be performed to determine which drugs will kill the organisms. Definitive antimicrobial therapy can then be initiated based on these results.
How to prepare for the test
A bone marrow aspiration or biopsy is necessary to collect the specimen for the culture. This procedure is performed by a physician, usually a hematologist (blood specialist).
Infants and children:
The preparation you can provide for this procedure depends on your child’s age, previous experiences, and level of trust. For specific information regarding how you can prepare your child, see the following topics:
- infant test or procedure preparation (birth to 1 year)
- toddler test or procedure preparation (1 to 3 years)
- preschooler test or procedure preparation (3 to 6 years)
- schoolage test or procedure preparation (6 to 12 years)
- adolescent test or procedure preparation (12 to 18 years)
How the test will feel
The specimen is collected from the back of the pelvic bone or from the sternum. The area is cleansed with antibacterial soap. The skin over the bone will be numbed with an anesthetic (a bee-sting sensation). Then a larger needle will be inserted through the skin into the bone and pushed into the cavity of the bone that contains the marrow.
A sample of bone marrow is aspirated into a syringe for analysis. Pressure and pain may occur with this procedure. Soreness at the site usually lasts only hours to a day or two.
If a bone marrow biopsy is also performed, a larger hollow-core needle is inserted, and a core sample of bone marrow is removed. A portion of the sample can be examined (biopsy sample) and another portion can be sent for culture. A bone marrow biopsy may cause feelings of pressure or pain. The pain is minimized with anesthesia of the bone (local anesthetic injected near the bone).
Why the test is performed
The test may be performed when unexplained fever is present or if infection of the bone marrow is suspected.
No organism growth in the culture media is normal.
What abnormal results mean
Infection of the bone marrow is present. The infection may be bacterial, viral, or fungal.
What the risks are
The risks include bleeding and infection.
A bone marrow aspirate or biopsy specimen may be sent for many different types of tests, which may, with proper indications, increase costs considerably.
by Sharon M. Smith, M.D.
All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.