A Multicenter Study of Beta-Lactamase Resistant Escherichia coli and Klebsiella pneumoniae Reveals High Level Chromosome Mediated Extended Spectrum β Lactamase Resistance in Ogun State, Nigeria

Figure 1

Culture plate showing synergy of clavulanic acid containing disk with ceftazidime in the double disk synergy test (DDST) for ESBL detection. A is augmentin + ceftazidime. B is ceftazidime alone. Zone of inhibition of A − zone of inhibition of B ≤ 5 mm; it is ESBL negative. Zone of inhibition of A − zone of inhibition of B ≥ 5 mm; it is ESBL positive.