Susceptibilities of Mycobacterium tuberculosis to isoniazid and rifampin on blood agar.
In this study, blood agar was used instead of 7H10 agar for the susceptibility testing of 34 clinical isolates of Mycobacterium tuberculosis to isoniazid (INH) and rifampin (RIF) in accordance with the NCCLS. The BACTEC 460 TB system (Becton Dickinson, Sparks, Md.) was used as a "gold standard." Results for both media were in agreement for RIF and INH at 100 and 94.1%, respectively. For INH, the specificity, sensitivity, positive predictive value, and negative predictive value were found to be 71.4, 100, 93.1, and 100%, respectively, while these values were 100% for RIF. In addition, the results of the susceptibility test performed with blood agar were obtained on day 14 of incubation. In conclusion, results were obtained much earlier with blood agar (2 weeks) than with 7H10 agar (3 weeks), and the results of this study suggest that blood agar may be used as an alternative medium for the susceptibility testing of M. tuberculosis to INH and RIF.
Coban
Ahmet Yilmaz
AY
Ondokuz Mayis University, Medical School, Department of Microbiology and Clinical Microbiology, 55139 Samsun, Turkey. noahmet@yahoo.com
Bilgin
Kemal
K
Uzun
Meltem
M
Tasdelen Fisgin
Nuriye
N
Akgunes
Alper
A
Cihan
Cigdem Cekic
CC
Birinci
Asuman
A
Durupinar
Belma
B
D000362:Agar; D000995:Antitubercular Agents / Q000494:pharmacology*; D001769:Blood / Q000382:microbiology*; D003470:Culture Media; D006801:Humans; D007538:Isoniazid / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests / Q000379:methods; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000302:isolation & purification; D011237:Predictive Value of Tests; D012293:Rifampin / Q000494:pharmacology*; D012680:Sensitivity and Specificity; D018088:Tuberculosis, Multidrug-Resistant / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000382:microbiology
D000995:Antitubercular Agents; D003470:Culture Media; D000362:Agar; D007538:Isoniazid; D012293:Rifampin