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Intro: Rapid reporting of Antimicrobial susceptibility testing (AST) of blood culture (BC) isolates is critical to optimize therapy. The standard turnaround time (TAT) for identification and AST using conventional disc diffusion (DD) is 48-96 hours after BC flags positive. EUCAST proposed a Rapid antimicrobial susceptibility test (RAST) based on standard DD. Results are recorded using species and time specific breakpoints (BP) at 4, 6, and 8 hours. EUCAST has recently proposed screening cut-offs for the detection of Escherichia coli and Klebsiella pneumoniae with ESBL or carbapenemases. The aim of the study was to evaluate the performance of EUCAST-RAST for screening ESBL and carbapenemases among E. coli and K. pneumoniae using positive BC. Methods: Positive BC (Escherichia Coli (n=100), Klebsiella pneumoniae (n=100) were included. The BC broths were processed for conventional ID and AST by standard EUCAST and RAST. ESBL and carbapenemase genes were characterized by PCR. Categorical results at 4, 6 and 8 h of incubation were compared with results for EUCAST standard 16–20 h disc diffusion. Findings: ESBL and carbapenemases genes were observed in 14 and 5 E.coli and 33 and 24 K.pneumoniae respectively. Majority isolates were positive for ESBL (CTX-M-15 or SHV) and carbapenemase (OXA-48 or NDM-1) genes. ESBL phenotype was successfully detected by RAST at 4,6,8 hrs for E.coli and K.pneumoniae. All carbapenem resistant isolates were successfully detected at 6 and 8 hrs however Major errors (false resistant) were high at 6 hrs: 95.7% and 69.7% which reduced to 8.4% and 50% at 8 hrs for E.coli and K.pneumoniae respectively. Conclusion: RAST can be successfully used for detection of ESBL and carbapenemase producing Enterobacteriaceae. However, for reporting susceptibility to carbapenems, further incubation of plates and recording of results at 16-20 hrs is advised. RAST can be used for implementing stewardship programs to optimize therapy.