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HardyCHROM CRE Banner mockup

Hardy Diagnostics is proud to introduce HardyCHROM CRE for the screening of E. coli, K. pneumoniae,
K. aerogenes, K. oxytoca, Enterobacter cloacae complex, and Serratia marcescens.

HardyCHROM™ CRE is a selective and differential chromogenic agar medium intended for the qualitative and presumptive detection from stool specimens of Escherichia coli that are non-susceptible to carbapenems as pink colonies and KES (Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Enterobacter cloacae complex, and Serratia marcescens) that are non-susceptible to carbapenems as blue colonies.

HardyCHROM™ CRE is intended as an aid in the detection, identification of colonization and control of these bacteria in a healthcare setting. HardyCHROM™ CRE is not intended to diagnose infection or guide therapy. Results can be interpreted after incubation for 18-24 hours. Subculture to non-selective medium is required for confirming identification, antimicrobial susceptibility testing and epidemiological typing.

A lack of growth or the absence of pink or blue colonies on HardyCHROM™ CRE does not preclude the presence of Escherichia coli and KES that are non-susceptible to carbapenems.

Growth Interpretation

  • Non-susceptible E. coli produces colonies that are rose to magenta in color with darker pink centers.

  • KlebsiellaEnterobacter, and Serratia spp. produce large, dark blue colonies (with or without a pink halo), are presumptive positive for carbapenem non-susceptible KES (Klebsiella aerogenesKlebsiella oxytocaKlebsiella pneumoniaeEnterobacter cloacae complex, and Serratia marcescens).

  • Colonies that are not pink to magenta, blue, or blue with pink halos are negative – No carbapenem non-susceptible Escherchia coli or KES detected.