Carba plus calculator spreadsheet

Isolates were tested for ESBL and carbapenemase production using MAST™ D68C and D73C combination disc sets, respectively. After overnight incubation at 35–37°C, the zone of inhibition was measured and recorded on an excel sheet and then transported to Mast group ESBL/AmpC and CARBA plus calculator spreadsheet (Mast Group, UK) and interpreted as ESBL or/and AmpC and carbapenemase positive or negative accordingly.

The presence of an ESBL and/or AmpC was determined with Cefpodoxime (10 μg), Cefotaxime (30 μg), Cefepime (30 μg) and Ceftazidime (30 μg) containing antibiotic discs (Mast Group, UK) by disc diffusion confirmation test. After the discs were inserted on inoculated plates, then they were incubated at 35–37 °C for 18–24 h aerobically. Finally, zones of inhibition were read and recorded on excel sheet. The data from the excel sheet was transported to Mast group ESBL/AmpC and CARBA plus calculator spreadsheet (Mast group, UK) and reported as negative or positive for ESBL or/and AmpC and finally the results were recorded.
The results were registered as resistant, intermediate and susceptible; but for the sake of analysis intermediate and resistant isolates were grouped together as resistant. Classification of MDR, XDR and PDR were carried out according to Magiorakos et al, definitions [4 (link)]. All the antibiotic disks were from Oxoid (Oxoid, UK) and Mast discs (Mast group, UK). The inhibition zone diameter was measured using caliper and recorded on excel sheet.