Mycobacterium – Blood
Mycobacterium testing from blood culture is indicated when there is suspicion of disseminated infection, e.g. in immunocompromised patients or suspicion of Mycobacterium chimera infection following open-chest heart surgery attributed to contamination of heater-cooler units during surgery.
|Test Requested||Required Requisition(s)||Specimen Type||Minimum Volume||Collection Kit|
Blood culture tube1,2
Submission and Collection Notes
Collect whole blood using aseptic technique in one of the following blood culture tubes:
- 10.0 ml SPS (yellow top tube) or
- 10.0 ml heparin (green top tube) or
- 10.0 ml isolator tube or
- Bactec Myco/F lytic medium (minimum volume 5.0 ml)
Do not submit blood collected in EDTA, coagulated blood, blood in blood culture medium other than Myco/F Lytic, serum or plasma.
Blood may contain antimicrobials which can delay or inhibit the growth of mycobacteria.
Preparation Prior to Transport
Label the specimen container with the patient’s full name, date of collection and one other unique identifier such as the patient’s date of birth or Health Card Number. Failure to provide this information may result in rejection or testing delay.
Specimens should be stored at room temperature and transferred to the lab ASAP.
Test Frequency and Turnaround Time (TAT)
The Mycobacterium blood test is performed daily – Monday to Saturday.
Turnaround time is up to 42 days from receipt by PHO Laboratory.
A positive culture is reported within 24 hours of growth. Depending on the species and treatment of the patient, a culture may grow within 1 to 2 weeks or take as long as 6 weeks.
Results are reported to the ordering physician or health care provider as indicated on the requisition.
All new isolates of M. tuberculosis complex are phoned to the submitter within 24 hours of identification.
Specimens that are positive for Mycobacterium tuberculosis are to be reported to the Medical Officer of Health as per Health Protection and Promotion Act.
Blood is tested using the BACTEC 9120 or BACTEC FX blood culture instruments (Becton Dickinson) using BACTEC Myco/ F Lytic culture media.