Objective To investigate the clinical application of mutations drug-resistant tuberculosis (MDR-TB) by polymerase chain reaction(PCR)-oligonucleotide probes. Methods 80 cases of MDR-TB were divided into observed group 40 cases and conventional group 40 cases, the resistant gene and the type of mutation were determined by polymerase chain reaction (PCR)-oligonucleotide probes. Results 78 isolates of 4 kinds of resistance genes (KatG,inhA,rpoB,embB) ,the mutation rates were 90.9% ,84.8% ,51.98% and 58.1% ;the gene of rpoB sensitivi-ty of 98.0% and specificity of 100% ,positive predictive value of 82.61% ,the rate of according with traditional drug susceptibility testing were 62.50% by polymerase chain reaction (PCR)-oligonucleotide probes;the serisitivity of the KatG gene mutation is of 50.56% ,specificity of 75% ,positive predictive value of 68.75% ,the rate of according with traditional drug susceptibility testing were 46.43% by polymerase chain reaction (PCR)-oligonucleotide probes;the observed group in focus significant absorption, absorption, invariability, deterioration were 32.5% ,62.5% ,5.0%, 0% ,higher than the conventional group(25.0% ,50.0% ,20.0% ,5.0% ) (χ2=3.98,χ2=3.92, P<0.05;χ2=6.78,χ2=6.80,P<0.01) ;observed group in 3 months after treatment,6 months,9 months sputum the conversion negative rate in observed group (65.0%, 77.5%, 85.0% ) higher than the conventional group (37.5%, 50.0%, 60.0%) (χ2=3.86,χ2=3.85,χ2=3.89,P both<0.05). Conclusion An analysis available 3 kind of MDR-TB, 4 kind gene by PCR-oligonucleotide;the observed group in curative effect is better than the conventional group in pa-tients with MDR-TB.

Objective To investigate drug resistance of mycobacterium tuberculosis,compare detecting effect of two methods and evaluate their value of clinical application.Methods All of the strains of mycoba-cterium tuberculosis were tested for resistance to RFP,INH,SM,PZA and EMB by the absolute concentration method on lowenste in-jensen medium and the mutation of the rpoB,katG,rpsL,pncA and embB resistanc genes in mycobacterium.Tuberculosis was tested by polymerase chain reaction-single strand conformation polymorphism(PCR-SSCP).Results 400 cases of tuberculosis drug resistance in patients with conventional susceptibility test resistance 316 cases (79.8%);resistant strains resistant gene detection 288,the mutation rate(72.0%):the RFP cases of resistance and resistance was significantly higher than that of SM,PZA and the EMB(resistant cases:F=2.45,2.56,2.69,P＜0.05;ResNtance:F=2.55,2.66,2.79,P＜0.05);the mutants and mutation rate of rpoB was higher than that of katG,rpsL,rpoB and embB(mutant:F=2.28,2.46,3.19,3.33,P＜0.05～O.01;mutation rate:F=2.36,2.61,3.25,3.45,P＜0.05～0.01);the gene mutation rate was higher in strains isolated from high concentration resistance than those in strains isolated from low concentration resistance;the more irregular treatment was longer,the rate of drug-resistant was higher(resistance:F=2.77,2.88,P＜0.05;mutation rate:F=2.72,2.85,P＜0.05).Conclusion PCR-SSCP is a sensitive and specific method for rapid detecting rpoB,katG,rpsL,pncA and embB gene mutations of mycobacterium tuberculosis.