Multicenter Evaluation of Xpert Carba-R Assay for Detection and Identification of the Carbapenemase Genes in Rectal Swabs and Clinical Isolates
The Journal of Molecular Diagnostics
Rapid detection of carbapenemase-producing organisms is clinically desirable for hospital infection control and antibiotic stewardship. In this multicenter study, the Xpert Carba-R assay was evaluated for detection of the five carbapenemase genes (blaKPC, blaNDM, blaIMP, blaOXA-48, and blaVIM) in 2404 nonduplicate rectal swabs of admitted inpatients and 521 Gram-negative isolates from four tertiary hospitals in China, compared with the reference growth-based method with DNA sequence analysis of colonies. All suspected false-positive results in rectal swabs were resolved by supplementary sequencing from broth cultures. A total of 197 blaKPC, 171 blaNDM, 142 blaIMP, 6 blaVIM, and 5 blaOXA-48 genes were detected by Xpert Carba-R in 417 rectal swabs, with overall positive and negative percentage agreements ranging from 94.5% to 100% and from 94.8% to 99.9%, respectively. Notably, 17.5% (263/1500) of inpatients had rectal colonization with carbapenem-nonsusceptible organisms detected in intensive care units, and 63.1% (166/263) were Xpert Carba-R positive. Among the 469 carbapenem-nonsusceptible and 52 carbapenem-susceptible isolates examined, 373 were Enterobacteriaceae, 55 were Pseudomonas aeruginosa, and 93 were Acinetobacter baumannii. Compared with the reference isolate sequencing, overall positive and negative percentage agreements were 99.7% and 98.0%, respectively. The intra-assay and interassay coefficient of variability values were both
Print ISSN: 1525-1578; Online ISSN: 1943-7811
Tenover, Fred C.; Jin, Xi; Zhang, Haomin; Wu, Shi; Qin, Xiaohua; Jia, Peiyao; Tang, Yi-Wei; Li, Min; Hu, Fupin; Yang, Qiwen; and Yu, Yunsong, "Multicenter Evaluation of Xpert Carba-R Assay for Detection and Identification of the Carbapenemase Genes in Rectal Swabs and Clinical Isolates" (2020). Biology Faculty Publications. 363.