Varıcı Balcı Fatma Kamer, Çavuşoğlu Cengiz
Dokuz Eylül University Faculty of Medicine, Department of Medical Microbiology, Divison of Medical Virology, Izmir, Turkey.
Ege University Faculty of Medicine, Department of Medical Microbiology, Izmir, Turkey.
Mikrobiyol Bul. 2018 Apr;52(2):123-134. doi: 10.5578/mb.66683.
Tuberculosis is still one of the most important public health problems worldwide. Due to the increase of multidrug-resistant (MDR) tuberculosis and extensively drug-resistant (XDR) tuberculosis cases, fast, practical and standardized methods need to be developed for the determination of drug resistance in Mycobacterium tuberculosis complex. The aim of this study was to compare the Sensititre MycoTB plate method with the gold standard agar proportion method (APM); in order to determine if the Sensititre MycoTB plate method is effective enough to be used instead of the APM. A total of 100 M.tuberculosis complex isolates, 36 with different resistance patterns and 64 sensitive to all first-line agents stored in culture collection of Ege University Faculty of Medicine Microbiology Department Laboratory, were used in the study. The susceptibility of rifampin, isoniazid, ethambutol, streptomycin, ofloxacin, moxifloxacin, amikacin, rifabutin, para-aminosalicylic acid, ethionamide, cycloserine and kanamycin for all the isolates were determined by APM and Sensititre MycoTB plate methods. APM was performed as defined by CLSI, Sensititre MycoTB plate method was performed as instructed by the manufacturer. Results were assessed in 95% confidence interval and sensitivity, specificity and categorical agreement values were determined. Results were obtained in 14 days using the Sensititre MycoTB plate method. Sensitivity and the specificity of the Sensititre MycoTB was between 86-100% and 95-100% respectively, while the categorical agreement between the two methods were 95-100% for the drugs tested. The sensitivities of the drugs were 100% except ethambutol and ethionamide. The specificity values for both of the drugs and categorical agreement were over 95%. All the drugs were in the 95% confidence interval (p< 0.001) and the greatest difference between the lower and upper levels of sensitivity and specificity confidence limits was found in ethambutol and ethionamide. MDR was detected in 16 isolates with the APM and in 20 isolates with the Sensititre MycoTB plate method. None of the isolates had XDR [in addition to MDR resistance against any fluoroquinolones and at least one of the second-line parenteral drugs (amikacin, kanamycin or capreomycin)]. As a result, owing to the short incubation period (14 days), high sensitivity, specificity and categorical agreement values, and the possibility for evaluating both first- and second-line agents and the quantitative values of drugs; the Sensititre MycoTB method was determined as an effective method that can be used especially in laboratories where the rate of MDR-TB isolates are high.
结核病仍然是全球最重要的公共卫生问题之一。由于耐多药（MDR）结核病和广泛耐药（XDR）结核病病例的增加，需要开发快速、实用且标准化的方法来测定结核分枝杆菌复合群中的耐药性。本研究的目的是将Sensititre MycoTB平板法与金标准琼脂比例法（APM）进行比较，以确定Sensititre MycoTB平板法是否足够有效，可替代APM。本研究共使用了100株结核分枝杆菌复合群分离株，其中36株具有不同的耐药模式，64株对所有一线药物敏感，这些菌株保存在伊兹密尔大学医学院微生物学系实验室的菌种保藏中心。采用APM和Sensititre MycoTB平板法测定所有分离株对利福平、异烟肼、乙胺丁醇、链霉素、氧氟沙星、莫西沙星、阿米卡星、利福布汀、对氨基水杨酸、乙硫异烟胺、环丝氨酸和卡那霉素的敏感性。APM按照美国临床和实验室标准协会（CLSI）的规定进行，Sensititre MycoTB平板法按照制造商的说明进行。结果在95%置信区间内进行评估，并确定敏感性、特异性和分类一致性值。使用Sensititre MycoTB平板法在14天内获得结果。Sensititre MycoTB的敏感性和特异性分别在86% - 100%和95% - 100%之间，而两种方法之间对于所测试药物的分类一致性为95% - 100%。除乙胺丁醇和乙硫异烟胺外，其他药物的敏感性均为100%。这两种药物的特异性值和分类一致性均超过95%。所有药物均在95%置信区间内（p < 0.001），敏感性和特异性置信区间上下限之间的最大差异出现在乙胺丁醇和乙硫异烟胺中。通过APM检测出16株耐多药分离株，通过Sensititre MycoTB平板法检测出20株耐多药分离株。没有分离株具有广泛耐药性[除了对任何氟喹诺酮类药物以及至少一种二线胃肠外给药药物（阿米卡星、卡那霉素或卷曲霉素）具有耐多药耐药性]。结果表明，由于培养期短（14天）、敏感性、特异性和分类一致性值高，以及能够评估一线和二线药物以及药物的定量值，Sensititre MycoTB方法被确定为一种有效的方法，尤其可用于耐多药结核病分离株比例较高的实验室。
