Turnaround times
The quoted turnaround time is from sample receipt in the laboratory, to results authorisation in the Laboratory Information Management system. The times do not include transport of specimen to the laboratory or the administrative process to print and post/email reports. Service users must allow for transport and reporting time when ordering tests.
Clinical background:
The PCR assay detects Mycobacterium tuberculosis complex DNA directly from primary specimens and includes a genotypic prediction for Rifampicin resistance. This may be carried out on a variety of samples (e.g. Sputum, BAL, tissue biopsies, aspirates, urine and CSF), ideally submit ≥6mls of CSF for best yield.
Please contact the laboratory to discuss other extra pulmonary sample types.
Specimen container paediatric:
Sputum, BAL, ETS or other sample in sterile Universal.
Specimen container adult:
Sputum, BAL or other respiratory sample in sterile Universal. Please telephone to discuss extra pulmonary sample types.
Minimum volume paediatric:
1ml
Minimum volume adult:
5ml
Special requirements:
Send to laboratory as quickly as possible. If delays likely, refrigerate at 2-8 deg C.
Sample stability:
Stable for up to 24 hrs.
Transport requirements:
Standard
Add on test:
N/A
Quality assurance:
UK National External Quality Assurance Scheme (UKNEQAS).
Interpretation:
Positive results include an indication of the presence of mutations conferring resistance to Rifampicin.
Negative results do not exclude a diagnosis of tuberculosis
Reference ranges:
N/A
Factors affecting result:
If delays likely, refrigerate at 2-8 deg C.
Referenced Documents:
UK SMI B 40: investigation of specimens for Mycobacterium species
Other info:
If suspected TB – mark as Biohazard.