Abstract: Objective To compare the difference of rifampicin fluorescence quantitative nucleic acid amplification detection(Xpert MTB/RIF) technology in the detection of different types of specimens of bone and joint tuberculosis lesions.
Methods A total of 245 patients with bone and joint tuberculosis were selected, and the pus(199 parts), cheese tissue(161 parts), granulation tissue(178 parts), and bone tissue(87 parts) in the lesion were obtained by surgery, and were respectively cultured with Mycobacterium tuberculosis Xpert MTB/RIF detection. The positive rates of 4 kinds of tissue samples were compared. The sensitivity and specificity of xpert MTB/RIF in the detection of bone and joint tuberculosis and rifampicin resistance gene were calculated.
Results Among 245 patients, 112(45.71%) were positive for Mycobacterium tuberculosis culture, 213(P＜0.01) were positive for Mycobacterium tuberculosis culture in 625 samples. Among 245 patients, 128(52.24%) were positive for Xpert MTB/RIF, and 255(255) were positive for Xpert MTB/RIF in 625 samples. The positive rate of xpert MTB/RIF was higher in pus than in cheese than in granulation than in bone(P＜0.01). The positive rate of the two methods was 185 cases(75.51%). The positive rates of pus, granulation, cheese and bone were higher than that of Mycobacterium tuberculosis(P＜0.05 or P＜0.01). The sensitivity and specificity of Xpert MTB/RIF were 96.43%, 84.96%, 97.92% and 93.75% respectively.
Conclusion To accurately diagnose osteoarticular tuberculosis and rifampicin resistance, it is necessary to collect as many specimens as possible, especially the pus in the focus. Xpert MTB/RIF technology is simple, rapid and accurate for the diagnosis of Mycobacterium tuberculosis infection and drug resistance.

Key words: tuberculosis, osteoarticular, nucleic acid amplification techniques, mycobacterium tuberculosis