Study On Activity Of The Joint Tuberculosis In Different Pathological Materials Of PCR Contrast Detection

Joint tuberculosis is one of the most common extra pulmonary tuberculosis. Recent years, with the global TB resurgencing, the incidence rate of joint tuberculosis is rising. Joint tuberculosis onsets insidiously,develops slowly, is always caused by Mycobacterium tuberculosis. With the progression of this disease,it will occur joint pain, swelling, muscle spasm and dysfunction. Its later period can appear chronic suppurative disease with joint deformity, sinus and fistula. Because there are almost no proliferation ability in chondrocytes, cartilage destruction will seriously affect the joint function, and the morbidity is high, so early diagnosis and effective anti TB chemotherapy are the key treatment of joint tuberculosis.Due to the early atypical clinical manifestations of joint tuberculosis,imaging examinations are lack of specificity. And also there are different limitations of each bacteriological inspection methods,therefore the early diagnosis of joint tuberculosis is difficult. Recent years, the domestic and foreign scholars attempt to detect Mycobacterium tuberculosis(MTB) by polymerase chain reaction(PCR) technique. MTB-PCR has a low false positive rate, and a fast detection speed, can be finished in 2 ~ 6 hours. But the positive rate of MTB-PCR detection in extrapulmonary tuberculosis isalso low. To further explore how to improve the positive rate of diagnosis of joint tuberculosis by MTB-PCR, we use fluorescence quantitative PCR method to detect active joint tuberculosis from granulation tissue, pus and caseous tissue, respectively. Then we compared the positive rate of MTB-PCR detection by different pathological materials, to explore the methods to improve the positive rate of MTB-PCR detection.In this study, we selected 43 cases of domestic advanced active joint tuberculosis patients from 2013 January to 2014 December, including 23 males and 20 female, aged 15 ~ 74 years old, average 45.6 years old. In these patients, 20 of them have tuberculosis knee joint, 15 of them have tuberculosis of hip joint, 3 cases of them have tuberculosis of shoulder joint,3 cases of them have tuberculosis of ankle and subtalar joint and 1 cases has tuberculosis of sacroiliac joint. The pus, caseous tissue and granulation tissue from operation were all detected by MTB-PCR. Comparison of the positive rate of MTB-PCR detection by different pathological materials, the results showed that: the positive rate bygranulation tissue(74.42%) was significantly higher than that of caseous tissue(58.14%) and pus(37.21%),and χ2 = 12.181, there is a significant difference in positive rate of MTB-PCR detection by three kinds of pathological materials kinds(P<0.05). At the same time, we found that the positive rate of PCR detection through combining these three kinds of joint pathological materials is 88.37%(38/43). We can draw a conclusion: there is differencein the positive rate of PCR with different pathological material to detect activity of joint tuberculosis; meawhile, positive rate of MTB-PCR detection through combining three pathological material is higher than single pathological materials testing, it proves the detection by combining various pathological material can improve the positive rate of MTB-PCR detection.