Abstract: Objective To compare the positive culture rate in 4 specimen types, including abscess, caseation, granulation tissues and necrotic bone from osteoarticular tuberculosis patients and to analyze the combined positive rate of BACTEC MGIT 960 Mycobacterial Detection (MGIT 960), Lowenstein-Jensen (L-J) culture and TB-PCR testing. Methods Fifty patients who diagnosed osteoarticular tuberculosis by pathological examination were admitted to Beijing Chest Hospital affiliated to Capital Medical University from June 2011 to May 2012. Specimens(50 cases of abscess, 42 cases of caseation, 48 cases of granulation and 43 cases of necrotic bone) were collected during surgery from those patients. All of the 4 specimen types were cultured by both MGIT 960 and L-J medium. The abscess specimen was also detected by PCR testing. Results The positive culture rates of abscess, caseation, granulation tissues and necrotic bone by MGIT 960 were 40.0%（20/50）, 33.3%（14/42）, 33.3%（16/48）and 41.9%（18/43）respectively, while which was 20.0%（10/50）, 14.3%（6/42）, 20.8%（10/48）and 16.3%（7/43）by L-J culture. The positive rate of abscess detected by PCR was 48.0%（24/50). The positive rate combined with the two methods of Mycobacterium tuberculosis culture was 50.0%(25/50),which was raised to 68.0%(34/50) when the PCR testing was also combined. Conclusion In order to increase the positive culture rate, a variety of specimens should be selected from the osteoarticular tuberculosis patients. MGIT 960 culture can be used as the preferred method of bacteriological diagnosis. The positive rate of detection can be further enhanced by the combined utilization of MGIT 960, Lowenstein-Jensen medium and PCR testing.

Key words: Tuberculosis, osteoarticular, Mycobacterium tuberculosis, Bacteriological techniques, Polymerase chain reaction