Gui Jing, Wang Feng, Hong Chuang-yue, Li Jin-li, Liang Jing
Department of Pathogenic Laboratory, Shenzhen Center for Chronic Disease Control, Shenzhen 518020, China.
Zhonghua Jie He He Hu Xi Za Zhi. 2013 Aug;36(8):567-71.
To study the drug resistance profile of Mycobacterium(M.) chelonae and M.abscessus and to evaluate the clinical application of Etest(epsilometer test) for susceptibility testing.
Twenty clinical isolates of M.abscessus and 16 clinical isolates of M.chelonae from clinical specimens were collected.Strain identification was carried out by GenoType Mycobacterium CM assay(Hain Lifescience, Germany). The accuracy was evaluated by comparing Etest results to those obtained by broth microdilution. Thirty-six isolates were tested against amikacin, cefoxitin, ciprofloxacin, clarithromycin, doxycycline, imipenem, linezolid, sulfamethoxazole and tobramycin. The agreement among MICs and interpretive category was evaluated. Chi-squared test was used to compare observed frequency of each of the 2 examples.
All of the isolates(36/36) were sensitive to amikacin and cefoxitin, and only 1 isolate(1/36) was resistant to clarithromycin, but more isolates(29/36) were resistant to ciprofloxacin, doxycycline, imipenem and sulfamethoxazole.For M.chelonae, only 2/16 were resistant to linezolid, and 7/16 resistant to tobramycin.For M.abscessus, more than 12/20 were resistant to linezolid and 16/20 resistant to tobramycin. The agreement between broth microdilution MICs and Etest MICs for 9 drugs was 149/324.With amikacin, clarithromycin, doxycycline and imipenem, the agreement for interpretive category was excellent(35/36), followed by sulfamethoxazole(34/36), which corresponded to rarely very major error of 2/36.With ciprofloxacin and tobramycin, agreement for interpretive category was 31/36 and 26/36.With cefoxitin and linezolid, the agreement of Etest MICs was the lowest(14/36), resulting in the resistant category.
Isolates of M.chelonae and M.abscessus exhibit far more susceptibility to amikacin, cefoxitin and clarithromycin than any other antimicrobial agents.Linezolid and tobramycin showed sensitivity to some isolates of M.chelonae.It is suitable for the Etest method as a simple reliable method for the drug susceptibility of amikacin, ciprofloxacin, clarithromycin, doxycycline, imipenem, and tobramycin except to cefoxitin and linezolid. The Etest method of determining sulfamethoxazole susceptibility should be careful.
研究龟分枝杆菌和脓肿分枝杆菌的耐药谱，并评估Etest（梯度扩散法）药敏试验的临床应用。
从临床标本中收集20株脓肿分枝杆菌临床分离株和16株龟分枝杆菌临床分离株。采用德国海因生命科学公司的GenoType Mycobacterium CM检测法进行菌株鉴定。通过将Etest结果与肉汤稀释法结果进行比较来评估准确性。对36株分离株进行阿米卡星、头孢西丁、环丙沙星、克拉霉素、多西环素、亚胺培南、利奈唑胺、磺胺甲恶唑和妥布霉素的药敏试验。评估最低抑菌浓度（MIC）和解释类别之间的一致性。采用卡方检验比较2个实例中每个实例的观察频率。
所有分离株（36/36）对阿米卡星和头孢西丁敏感，仅1株（1/36）对克拉霉素耐药，但更多分离株（29/36）对环丙沙星、多西环素、亚胺培南和磺胺甲恶唑耐药。对于龟分枝杆菌，仅2/16对利奈唑胺耐药，7/16对妥布霉素耐药。对于脓肿分枝杆菌，超过12/20对利奈唑胺耐药，16/20对妥布霉素耐药。9种药物的肉汤稀释法MIC与Etest MIC之间的一致性为149/324。对于阿米卡星、克拉霉素、多西环素和亚胺培南，解释类别一致性极佳（35/36），其次是磺胺甲恶唑（34/36），对应极少的2/36的非常重大错误。对于环丙沙星和妥布霉素，解释类别一致性分别为31/36和26/36。对于头孢西丁和利奈唑胺，Etest MIC的一致性最低（14/36），导致耐药类别。
龟分枝杆菌和脓肿分枝杆菌分离株对阿米卡星、头孢西丁和克拉霉素的敏感性远高于其他抗菌药物。利奈唑胺和妥布霉素对部分龟分枝杆菌分离株显示出敏感性。Etest方法适用于阿米卡星、环丙沙星、克拉霉素、多西环素、亚胺培南和妥布霉素的药敏试验，是一种简单可靠的方法，但不适用于头孢西丁和利奈唑胺。采用Etest方法测定磺胺甲恶唑药敏时应谨慎。
