Simultaneous and early detection of Mycobacterium tuberculosis resistance to antituberculosis drugs using an indirect series piezoelectric system.

Emergence of drug-resistance tuberculosis (DR-TB) represents a serious threat to the world. Most countries, especially the developing countries, lack efficacious and inexpensive tools for early detection of Mycobacterium tuberculosis (M. tuberculosis) resistance to antituberculosis drugs and for preventing the carriers from acquiring further resistance. This report describes an indirect series piezoelectric (ISP) system for simultaneous and early detection of M. tuberculosis resistance to antituberculosis drugs. The ISP system can continually monitor the frequency shift change profiles of 32 detection cells resulting from the changes of volatile metabolites group during M. tuberculosis growth. The quantification detection time (QDT) obtained from the frequency shift change profile was found to be characterisitc of M. tuberculosis resistance. A drug-free chamber was used as a control, in which 1% of M. tuberculosis isolate was added. By comparing the QDT obtained from growth of M. tuberculosis isolate in each drug-containing chamber with that in a drug-free chamber, forty strains of clinical M. tuberculosis isolates were categorized by our method. Comparison was also made using the agar proportion method (APM) and the BACTEC™ MGIT™ 960 system. The mean time for interpretive category of M. tuberculosis resistance measured by the ISP system is (111.7 ± 28.45)h, which is more rapid than by the APM [(600.0 ± 50.30)h] and the BACTEC™ MGIT™ 960 system [(140.3 ± 39.52)h]. The present system is accurate, rapid and cost-effective with a wide application in early detection of DR-TB in the developing countries.