National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory for Drug Resistant Tuberculosis Research, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beiguan St #9, Beijing 101149, China.
Department of Orthopedics, Beijing Bone and Joint Tuberculosis Diagnosis and Treatment Center, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing, China.
J Infect. 2019 Aug;79(2):153-158. doi: 10.1016/j.jinf.2019.06.006. Epub 2019 Jun 14.
The diagnosis of osteoarticular tuberculosis (TB) remains challenging and results in under- or over-diagnosis. The aim of the present study was to evaluate performance of the novel next-generation Xpert MTB/RIF Ultra (Xpert Ultra) in comparison to culture and Xpert MTB/RIF (Xpert) for osteoarticular TB diagnosis in high burden settings.
Osteoarticular TB suspected cases were enrolled consecutively during June 2017 to June 2018 at Beijing Chest Hospital and their pus specimens were subjected to smear, culture, Xpert and Xpert Ultra. Drug susceptibility testing (DST) was conducted for all of the recovered isolates. The performances of Xpert Ultra and Xpert were evaluated using composite reference standard (CRS) as gold standard, which included clinical, laboratory, histopathological, radiological and ≥6 months' follow-up data.
In total, 186 patients were recruited, and 132 of them were diagnosed with osteoarticular TB according to CRS. The direct head-to-head performance comparison for M. tuberculosis detection showed that Xpert Ultra (90.91%, 120/132) produced a higher sensitivity than Xpert (78.79%, 104/132, P = 0.006) and culture (39.39%, 52/132, P < 0.001). When Xpert Ultra outcomes were integrated, the percentage of confirmed osteoarticular TB case increased from 84.09% (111/132) to 93.94% (124/132). The specificities of Xpert and Xpert Ultra were 100% (34/34) and 97.06% (33/34), respectively. Both Xpert Ultra and Xpert accurately identified all of the 9 rifampicin (RIF)-resistant and 38 RIF-sensitive cases defined by phenotypic DST. Therefore, Xpert Ultra was 100% concordant with phenotypic DST for the detection of RIF resistance.
Xpert Ultra detected significantly more osteoarticular TB cases than Xpert or culture, making it a useful tool for rapid diagnosis of osteoarticular TB.
骨关节结核（TB）的诊断仍然具有挑战性，导致诊断不足或过度诊断。本研究的目的是评估新型下一代 Xpert MTB/RIF Ultra（Xpert Ultra）在高负担环境中与培养和 Xpert MTB/RIF（Xpert）相比用于骨关节 TB 诊断的性能。
2017 年 6 月至 2018 年 6 月，连续在北京胸科医院招募骨关节 TB 疑似病例，并对其脓液标本进行涂片、培养、Xpert 和 Xpert Ultra。对所有分离株进行药物敏感性试验（DST）。使用复合参考标准（CRS）作为金标准评估 Xpert Ultra 和 Xpert 的性能，CRS 包括临床、实验室、组织病理学、影像学和≥6 个月的随访数据。
共纳入 186 例患者，其中 132 例根据 CRS 诊断为骨关节 TB。MTB 检测的直接头对头性能比较显示，Xpert Ultra（90.91%，120/132）的敏感性高于 Xpert（78.79%，104/132，P=0.006）和培养（39.39%，52/132，P<0.001）。当整合 Xpert Ultra 结果时，确诊骨关节 TB 病例的比例从 84.09%（111/132）增加到 93.94%（124/132）。Xpert 和 Xpert Ultra 的特异性分别为 100%（34/34）和 97.06%（33/34）。Xpert Ultra 和 Xpert 均准确识别了表型 DST 定义的 9 例利福平（RIF）耐药和 38 例 RIF 敏感的所有病例。因此，Xpert Ultra 对 RIF 耐药性的检测与表型 DST 完全一致。
Xpert Ultra 比 Xpert 或培养检测到的骨关节 TB 病例明显更多，是快速诊断骨关节 TB 的有用工具。
