Biochemistry
Haematology and Transfusion
Clinical Microbiology (Including Virology)
Cellular Pathology
General Information
Immunology
Molecular Pathology
Preferred Sample Type
Suitable Specimen Types
Sputum BAL Fluid Tissue Biopsy Lymph Node Pus Tissue CSFMycobacterial detection (TB PCR)
Specimen Volume
Sputum, BAL, sterile fluids, pus - minimum 2 mL; CSF - minimum 6mL; Tissue - any visible amount of tissue.Specimen Transport
Sample should be transported to the laboratory as soon as possibleTurnaround Time
24 hours (urgent requests) and 48 hours (routine requests)Sample Stability
If transport is delayed, samples can be refrigerated for up to 24 hoursGeneral Information
The Xpert MTB/RIF Ultra test for use with the Cepheid GeneXpert System is a PCR in-vitro diagnostic test for: 1) the detection of Mycobacterium tuberculosis complex DNA and 2) the detection of rifampin resistance associated mutations of the rpoB gene.
The Xpert MTB/RIF Ultra test is intended for use with specimens from patients for whom there is clinical suspicion of tuberculosis (TB) and who have received no antituberculosis therapy, or less than 3 days of therapy in the last 6 months.
Limitations
- A positive test result does not necessarily indicate the presence of viable organisms. It is however, presumptive for the presence of MTB and RIF resistance.
- Test results might be affected by antecedent or concurrent antibiotic therapy. Therefore, therapeutic success or failure cannot be assessed using this test because DNA might persist following antimicrobial therapy.
- Mutations or polymorphisms in primer or probe binding regions may affect detection of new or unknown MDR-MTB or RIF resistant strains resulting in a false negative result.
Please Note
- The manufacturer of the assay has only validated this test for sputum samples. All other specimen types listed are currently undergoing in-house validation and can be tested but will be forwarded to NMRS Heartlands hospital when necessary.
- Bloods, urines, swabs and faecal specimens which will be rejected as unsuitable for TBPCR.
- Specimens must be collected within a sterile universal container
- Please make sure sample forms and/or bags are labelled as biohazard
Accreditation: This test is not currently UKAS accredited.
Information Sharing: If your sample needs to be referred or a notifiable disease is detected from your sample, your details and sample may be shared with the UK Health Security Agency (UKHSA). This is a legal requirement. The UKHSA is sponsored by the Department of Health and Social Care.
Patient Preparation
For general aspects of taking respiratory samples we recommend that users follow their local protocols.
Notes
Specifications
- EQA Status: NEQAS
- EQAS Scheme: Yes