Mycobacterium tuberculosis complex Antimicrobial Susceptibility Testing (Culture)

Test Order Name - Mycobacterium tuberculosis Complex Drug Susceptibility Testing (First Line)

Synonym(s) - Antimycobacterial susceptibility testing to aid in the treatment of patients with tuberculosis.

Methodology - The BACTEC MGIT 960 is used as a rapid qualitative procedure for susceptibility testing of M.tb. complex from a culture for the following antimycobacterial drugs: isoniazid (INH), rifampin, ethambutol, pyrazinamide, streptomycin.

Acceptable Specimen Type(s) for Testing - Pure culture isolates of M.tb. complex from any specimen type/source.

Transport / Collection Medium - Pure cultures on Lowenstein-Jensen Slants, BACTEC MGIT Liquid Medium, Middlebrook 7H9 Broth

Storage and Preservation of Specimen - Freshly grown culture of M.tb. complex: no more than 14 days from inoculation for solid culture and no more than 5 days from inoculation for BACTEC MGIT liquid media. Keep culture at ambient temperature to preserve if over the recommended age of culture.

Minimum Volume Required - 4 milliliters of BBL Middlebrook 7H9 broth or MGIT broth.

Additional Collection Instructions - Fresh, pure growth of M.tb. complex is required for this test. Identification of M.tb. complex must be confirmed before testing.

Additional Required Information - Collection date and specimen source required

Send Out? - No

Turnaround Time - 13 days

Testing Restrictions - None

Limitations / Notes / Disclaimers - The BACTEC MGIT System susceptibility test does not interpret the degree of susceptibility of the isolate being tested. Results are reported as either “S” (susceptible) or “R” (resistant) for the drug and concentration tested.