Carbapenem Disks on MacConkey Agar in Screening Methods for Detection of Carbapenem-Resistant Gram-Negative Rods in Stools

Direct plating of simulated stool specimens on MacConkey agar (MCA) with 10-mu g ertapenem, meropenem, and imipenem disks allowed the establishment of optimal zone diameters for the screening of carbapenem-resistant Gram-negative rods (CRGNR) of <= 24 mm (ertapenem), <= 34 mm (meropenem), and <= 32 mm (imipenem).