Muñoz Constanza, Zumarán Cecilia, González Tamara, Wozniak Aniela, Castillo Claudia, García Patricia
Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.
Laboratorio de Microbiología, Servicio de Laboratorios Clínicos, Red de Salud UC-CHRISTUS, Chile.
Rev Chilena Infectol. 2017 Aug;34(4):326-332. doi: 10.4067/s0716-10182017000400326.
The detection of carbapenemase-producing gram negative bacilli is complicated, because there are available multiple options of test. The confirmation of the enzyme by molecular characterization is not available in all laboratories in our country.
To propose a fast, efficient and simple strategy to detect and confirm CPB.
39 CPB isolates and 8 non-producing were used to evaluate the phenotypic test Carba NP, CarbAcineto NP and Blue-Carba, validating the test Xpert® Carba-R, to be used directly with bacterial colonies with conventional PCR.
The sensitivity of Carba NP, CarbAcineto NP and Blue-Carba was 79,5; 87,2 y 84,6%, respectively; and specificity was 79.5; 87.2 and 84.6%, respectively. The limit of detection of Xpert® Carba-R was different for each carbapenemasa: 40.8 ufc/reaction to KPC and NDM and 30.6 ufc/reaction to VIM.
On isolates with decreased susceptibility to carbapenems we propose to use as screening the test CarbAcineto NP, follow by Xpert®Carba-R to characterize the carbapenemase and adopt specific infection control measures.
产碳青霉烯酶革兰氏阴性杆菌的检测较为复杂，因为有多种检测方法可供选择。我国并非所有实验室都能通过分子特征鉴定来确认该酶。
提出一种快速、高效且简单的策略来检测和确认产碳青霉烯酶细菌（CPB）。
使用39株CPB分离株和8株非产酶株来评估Carba NP、CarbAcineto NP和Blue-Carba表型试验，验证Xpert® Carba-R检测，该检测可直接用于细菌菌落的常规PCR。
Carba NP、CarbAcineto NP和Blue-Carba的敏感性分别为79.5%、87.2%和84.6%；特异性分别为79.5%、87.2%和84.6%。Xpert® Carba-R对每种碳青霉烯酶的检测限不同：对KPC和NDM为40.8 cfu/反应，对VIM为30.6 cfu/反应。
对于对碳青霉烯类药物敏感性降低的分离株，我们建议先用CarbAcineto NP试验进行筛查，然后用Xpert® Carba-R鉴定碳青霉烯酶，并采取特定的感染控制措施。
