Table 2. Summary of misidentified colonies by CHROMagar ESBL media when compared to MALDI-TOF-MS for isolate identification.

CHROMagar ESBL colony colour	No. isolated	CHROMagar presumptive identification	Total no. of isolates misidentified (%)	Species misidentified by CHROMagar	No. (%) of species misidentified
Dark pink/red	543	Escherichia coli	33 (6.1 %)	Citrobacter freundii complex	15 (45.4 %)
				Klebsiella pneumoniae	11 (33.3 %)
				Enterobacter cloacae complex	3 (9.1 %)
				Acinetobacter baumannii	2 (6.1 %)
				Proteus mirabilis	2 (6.1 %)
Metallic blue	267	KEC spp.	73 (27.3 %)	Escherichia coli	50 (68.5 %)
				Proteus mirabilis	6 (8.2 %)
				Kluyvera ascorbate	4 (5.5 %)
				Unidentified, GNB	4 (5.5 %)
				Kluyvera cryocrescens	2 (2.7 %)
				Pseudomonas aeruginosa	2 (2.7 %)
				Unidentified, GPC	2 (2.7 %)
				Acinetobacter baumannii	1(1.4 %)
				Aeromoas caviae	1 (1.4 %)
				Pseudomonas mendocina	1 (1.4 %)

GNB, Gram-negative bacilli; GPC, Gram-positive cocci; KEC, Klebsiella species/Enterobacter species/Citrobacter species.