Exploring New Delhi Metallo Beta Lactamases in Klebsiella pneumoniae and Escherichia coli: genotypic vs. phenotypic insights

Table 4 Comparative analysis of phenotypic vs. genotypic methods in carbapenemase gene identification - overall performance Metrics

Carbapenem-resistant bacterial strains	PCR and Lateral flow categories	Subcategories	NGS		PPV %	NPV%	Kappa (CI 95%)
Carbapenem-resistant bacterial strains	PCR and Lateral flow categories	Subcategories	Detection	Variants	PPV %	NPV%	Kappa (CI 95%)
E. coli	Positive	bla_NDM (n = 5)	5 (100%)	bla_NDM−5	100	100	0.91[0.66 − 1]
	Positive	co-producers of bla_NDM and bla_OXA (n = 5)	5 (100%)	bla_OXA−1, bla_OXA−181	100	100	0.91[0.66 − 1]
	Negative	bla_NDM and bla_OXA (n = 2)	Not detected
	Negative	bla_OXA without bla_NDM (n = 2)	2 (100%)	bla_OXA−181	100	100	0.34[0.15 − 0.55]
K. pneumoniae	Positive	bla_NDM (n = 5)	2 (40%)	bla_NDM−5	40	40	0.20[0.10 − 0.2]^*
	Positive	co-producers of bla_NDM and bla_OXA (n = 5)	5 (100%)	bla_OXA−232	100	100	0.91[0.66 − 1]
	Negative	bla_NDM and bla_OXA (n = 2)	Not detected
	Negative	bla_OXA without bla_NDM (n = 2)	2 (100%)	bla_OXA−232	100	100	0.34[0.15 − 0.55]

The comparative effectiveness of phenotypic (lateral flow) and genotypic (PCR) methods was assessed through whole genome sequencing to detect the presence of the New Delhi Metallo-beta-lactamases (bla_NDM) gene in carbapenem-resistant Escherichia coli and Klebsiella pneumoniae (CREK). Numbers expressed in percentage (%). PPV: Positive Predictive Value; NPV: Negative Predictive Value

ISSN: 1476-0711