SUSCEPTIBILITY TESTING OF M. TUBERCULOSIS COMPLEX

​For mycobacteria isolated in CTBL or in other laboratories

​Fresh pure culture of M. tuberculosis isolate on slant in sealed screw-capped plastic tube. Tube should be tightly closed, labelled with identifying lab number and placed in a biohazard-labelled ziplock bag. Pack, transport and notify CTBL (in advance) and MOH of the transfer, according to MOH-BATA requirements.

Regional laboratories must make arrangements with the lab for the MOH-Import Permit before sending specimens and packaging must conform to international standards (IATA). The request form should state the name and address of referring laboratory, organism identification, clinical source, patient particulars with relevant clinical information, clinician in-charge and requester's contact number.

The type of test request should be specified as TB Culture for Susceptibility Testing. Forms are to be placed in a separate sealed plastic bag in the outer package.

​MGIT non-radiometric. Minimum Inhibitory Concentration breakpoint testing.

Drugs available for TB culture Susceptibility Testing (µg/ml):
1st line: Pyrazinamide (100), rifampicin (0.5), isoniazid (0.1), ethambutol (5)
2nd line: Levofloxacin (1), amikacin (1), clofazimine (0.5).
Extended panel: Streptomycin (1), ethionamide (5) and PAS (4).

Other drugs:

High-level Streptomycin (4)
High-level Isoniazid (0.4)
Capreomycin  (2.5)

Linezolid (1)

Moxifloxacin (0.25µg). If the initial test result shows resistance, the isolate will be retested at 0.25 and 1µg/ml

​Susceptible, Resistant

​2 -4 weeks. Affected by slow-growing isolates.

​Monday - Friday

​For referred M. tuberculosis complex isolates from other laboratories, please contact CTBL before sending isolate.