Biomaterial Database

Evaluation of the BACTEC radiometric method for detection of 1% resistant populations of Mycobacterium tuberculosis. 1985

J J Tarrand, and D H Gröschel

BACTEC and conventional methods of antimicrobial susceptibility testing were compared with the use of artificial mixtures of 1% resistant and 99% susceptible Mycobacterium tuberculosis strains. Inocula for the assays were prepared on the basis of radiometric readings. A total of 40 resistant strains were tested: 18 were resistant to isoniazid, 16 to rifampin, 5 to streptomycin, and 1 to ethambutol. The BACTEC method detected 27 of 39 strains at the greater than 0.5% resistance level, whereas the conventional plate method detected only 8 of 40. In addition, the results of the BACTEC assay were closer to the expected 1% resistance level (0.7%) than were the data obtained with the proportional plate method (0.3%; P = 0.001). This difference was most striking with the isoniazid-resistant strains. The precision of the assay methods was quite different (coefficients of variation, 26% for BACTEC and 54% for plates; P = 0.0002). Streptomycin-resistant strains had the highest variability in both assay methods. A 1-day delay in calculating the BACTEC data after the control vial reading was equal to or greater than 30 resulted in a 25% reduction in the calculated level of resistance (0.7 to 0.53). By adhering exactly to the recommended procedures for the BACTEC test method and by using log-phase inocula, this method shows better precision and accuracy at the 1% resistance level than does the proportional plate method.

UI	MeSH Term	Description	Entries
D007538	Isoniazid	Antibacterial agent used primarily as a tuberculostatic. It remains the treatment of choice for tuberculosis.	Isonicotinic Acid Hydrazide,Ftivazide,Isonex,Isonicotinic Acid Vanillylidenehydrazide,Phthivazid,Phthivazide,Tubazide,Acid Vanillylidenehydrazide, Isonicotinic,Hydrazide, Isonicotinic Acid,Vanillylidenehydrazide, Isonicotinic Acid
D008826	Microbial Sensitivity Tests	Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).	Bacterial Sensitivity Tests,Drug Sensitivity Assay, Microbial,Minimum Inhibitory Concentration,Antibacterial Susceptibility Breakpoint Determination,Antibiogram,Antimicrobial Susceptibility Breakpoint Determination,Bacterial Sensitivity Test,Breakpoint Determination, Antibacterial Susceptibility,Breakpoint Determination, Antimicrobial Susceptibility,Fungal Drug Sensitivity Tests,Fungus Drug Sensitivity Tests,Sensitivity Test, Bacterial,Sensitivity Tests, Bacterial,Test, Bacterial Sensitivity,Tests, Bacterial Sensitivity,Viral Drug Sensitivity Tests,Virus Drug Sensitivity Tests,Antibiograms,Concentration, Minimum Inhibitory,Concentrations, Minimum Inhibitory,Inhibitory Concentration, Minimum,Inhibitory Concentrations, Minimum,Microbial Sensitivity Test,Minimum Inhibitory Concentrations,Sensitivity Test, Microbial,Sensitivity Tests, Microbial,Test, Microbial Sensitivity,Tests, Microbial Sensitivity
D009169	Mycobacterium tuberculosis	A species of gram-positive, aerobic bacteria that produces TUBERCULOSIS in humans, other primates, CATTLE; DOGS; and some other animals which have contact with humans. Growth tends to be in serpentine, cordlike masses in which the bacilli show a parallel orientation.	Mycobacterium tuberculosis H37Rv
D011933	Reagent Kits, Diagnostic	Commercially prepared reagent sets, with accessory devices, containing all of the major components and literature necessary to perform one or more designated diagnostic tests or procedures. They may be for laboratory or personal use.	Diagnostic Reagent Kits,Diagnostic Reagents and Test Kits,Diagnostic Test Kits,In Vitro Diagnostic Device,In Vitro Diagnostic Devices,In Vitro Diagnostic Medical Device,In Vitro Diagnostic Medical Devices,Kits, Diagnostic Reagent,Diagnostic Reagent Kit,Diagnostic Test Kit,Kit, Diagnostic Reagent,Kit, Diagnostic Test,Kits, Diagnostic Test,Reagent Kit, Diagnostic,Test Kit, Diagnostic,Test Kits, Diagnostic
D003470	Culture Media	Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.	Media, Culture
D004977	Ethambutol	An antitubercular agent that inhibits the transfer of mycolic acids into the cell wall of the tubercle bacillus. It may also inhibit the synthesis of spermidine in mycobacteria. The action is usually bactericidal, and the drug can penetrate human cell membranes to exert its lethal effect. (From Smith and Reynard, Textbook of Pharmacology, 1992, p863)	Dexambutol,EMB-Fatol,EMB-Hefa,Etambutol Llorente,Ethambutol Hydrochloride,Etibi,Miambutol,Myambutol,EMB Fatol,EMB Hefa,Hydrochloride, Ethambutol,Llorente, Etambutol
D012293	Rifampin	A semisynthetic antibiotic produced from Streptomyces mediterranei. It has a broad antibacterial spectrum, including activity against several forms of Mycobacterium. In susceptible organisms it inhibits DNA-dependent RNA polymerase activity by forming a stable complex with the enzyme. It thus suppresses the initiation of RNA synthesis. Rifampin is bactericidal, and acts on both intracellular and extracellular organisms. (From Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 9th ed, p1160)	Rifampicin,Benemycin,Rifadin,Rimactan,Rimactane,Tubocin
D013307	Streptomycin	An antibiotic produced by the soil actinomycete Streptomyces griseus. It acts by inhibiting the initiation and elongation processes during protein synthesis.	Estreptomicina CEPA,Estreptomicina Clariana,Estreptomicina Normon,Strepto-Fatol,Strepto-Hefa,Streptomycin Grünenthal,Streptomycin Sulfate,Streptomycin Sulfate (2:3) Salt,Streptomycin Sulphate,Streptomycine Panpharma,Strepto Fatol,Strepto Hefa