Mycobacterium Tuberculosis Laboratory
The BARC SA Mycobacterium Tuberculosis (TB) laboratory is the largest accredited Level 3 facility in Southern Africa and has been accredited by several international agencies. Not only is our facility equipped with the state of the art laboratory technology, we also have highly trained qualified staff to ensure a more rapid and accurate diagnosis of Mycobacterium tuberculosis. We are the Regional TB laboratory for the Aids Clinical Trials Group (ACTG) network. Our priority is to ensure high quality standard of sample processing and to maintain the safety of all staff members at all times.
The TB laboratory carries out protocol-specific tuberculosis assays (new diagnostic assays are continuously evaluated for diagnostic purposes) which include:
Microscopy
Acid Fast Bacilli (AFB) smears are treated with Auromine O stain and counterstained with Ziehl Neelsen for confirmation.
Culture
The TB laboratory utilises both liquid (MGIT) and solid (Lowestein Jensen slope) based media for the culturing of Mycobacterium samples.
Identification
- GeneXpert: A semi-quantitative nested real time PCR detection of MTB complex DNA including the detection of resistance to the drug Rifampicin.
- MPT64: Rapid Chromatographic Immunoassay for qualitative detection of MTB complex Antigen from positive cultures.
- Hain MTBDRplus: This testing method is a PCR Reverse hybridisation line probe strip assay identification of Mycobacterium species and drug resistance to INH and RIF on positive MTB cultures or smear positive samples.
- Abbott RealTime MTB assays. This method detects TB infection and differentiates both Rif and INH resistance.
Drug Susceptibility testing (DST)
The TB laboratory offers both first-line and second-line phenotypic drug susceptibility testing of positive culture samples.
First-line drugs: Streptomycin, Isoniazid, Ethambutol, Rifampicin and Pyrazinamide
Second-line drugs-Ofloxacin, Moxifloxacin, kanamycin Amikacin and Ethionamide
Storage of MTB Isolates
As an added service to clients, we offer long-term storage of positive isolates. The isolates are stored in microbanks at -70 ⁰C.