Laboratory Systems Development Branch, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
J Clin Microbiol. 2012 Apr;50(4):1233-9. doi: 10.1128/JCM.06479-11. Epub 2012 Feb 1.
We present a statistical summary of results from the Model Performance Evaluation Program (MPEP) for Mycobacterium tuberculosis Drug Susceptibility Testing, 1994 to 2008, implemented by the U.S. Centers for Disease Control and Prevention (CDC). During that period, a total of 57,733 test results for culture isolates were reported by 216 participating laboratories for the first-line antituberculosis drugs used in the United States-isoniazid (INH), rifampin (RMP), ethambutol (EMB), and pyrazinamide (PZA). Using Clinical Laboratory and Standards Institute (CLSI)-recommended concentrations for one or more of three methods, agar proportion (AP), BACTEC460 (Bactec), and MGIT-960 (MGIT), yielded overall agreement of 97.0% for first-line drugs. For susceptible strains, agreement was 98.4%; for resistant strains, agreement was 91.0%, with significantly lower accuracy (chi-square test, P < 0.0001). For resistant strains, overall agreement by methods was 91.3% for AP, 93.0% for Bactec, and 82.6% for MGIT and by drugs was 92.2% for INH, 91.5% for RMP, 79.0% for EMB, and 97.5% for PZA. For some strains, performance by method varied significantly. Use of duplicate strains in the same shipment and repeat strains over time revealed consistent performance even for strains with higher levels of interlaboratory discordance. No overall differences in performance between laboratories were observed based on volume of testing or type of facility (e.g., health department, hospital, independent). By all methods, decreased performance was observed for strains with low-level INH resistance, RMP resistance, and EMB-resistant strains. These results demonstrate a high level of performance in detection of drug-resistant M. tuberculosis in U.S. laboratories.
我们呈现了美国疾病控制与预防中心（CDC）实施的结核分枝杆菌药物敏感性试验模型性能评估计划（MPEP）1994 年至 2008 年的统计结果摘要。在此期间，共有 216 个参与实验室报告了 57733 份培养分离物的测试结果，用于检测美国一线抗结核药物，包括异烟肼（INH）、利福平（RMP）、乙胺丁醇（EMB）和吡嗪酰胺（PZA）。使用临床实验室标准化研究所（CLSI）推荐的浓度，对于一种或多种三种方法，琼脂比例（AP）、BACTEC460（Bactec）和 MGIT-960（MGIT），总体上对一线药物的一致性为 97.0%。对于敏感菌株，一致性为 98.4%；对于耐药菌株，一致性为 91.0%，准确性显著降低（卡方检验，P < 0.0001）。对于耐药菌株，方法间总体一致性为 AP 91.3%，Bactec 93.0%，MGIT 82.6%，药物间为 INH 92.2%，RMP 91.5%，EMB 79.0%，PZA 97.5%。对于某些菌株，方法的性能存在显著差异。在同一批货中使用重复的菌株，并随着时间的推移重复菌株，即使对于实验室间一致性较高的菌株，也能显示出一致的性能。根据测试量或设施类型（例如，卫生部门、医院、独立），未观察到实验室间性能的总体差异。所有方法均观察到低水平 INH 耐药、RMP 耐药和 EMB 耐药菌株的性能下降。这些结果表明，美国实验室在检测耐多药结核分枝杆菌方面具有很高的性能。
