Rapid Direct Testing of Susceptibility of Mycobacterium tuberculosis to Isoniazid and Rifampin on Nutrient and Blood Agar in Resource-Starved Settings

Satti L., Ikram A., Coban A. Y., Martin A.

JOURNAL OF CLINICAL MICROBIOLOGY, vol.50, no.5, pp.1659-1662, 2012 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 50 Issue: 5
  • Publication Date: 2012
  • Doi Number: 10.1128/jcm.00013-12
  • Journal Name: JOURNAL OF CLINICAL MICROBIOLOGY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1659-1662
  • Ondokuz Mayıs University Affiliated: Yes

Abstract

In this study, we evaluated the performance of blood agar (by macroscopic growth) and nutrient agar (by a microcolony detection method) for drug susceptibility testing of Mycobacterium tuberculosis against rifampin (RIF) and isoniazid (INH), using 67 smear-positive sputum specimens. The direct proportion method on Lowenstein-Jensen (LJ) medium was used as the "gold standard." Compared with LJ medium, results for both media were in 100% agreement for RIF, while for INH the agreement levels for blood agar and nutrient agar were 98% and 95%, respectively. Within 2 weeks, 100% of specimens yielded results on blood agar, while 96.8% of specimens yielded results on nutrient agar. Our study showed that blood agar and nutrient agar can be used as alternative media for direct susceptibility testing of RIF and INH, especially in resource-poor settings.