LAMP assays for the simple and rapid detection of clinically important urinary pathogens including the detection of resistance to 3rd generation cephalosporins

Table 3 Comparison of culture and LAMP method results on 161 urine samples

LAMP	Culture		Sensitivity	Specificity	PPV	NPV	K
LAMP	Positive	Negative	% [95% CI]	% [95% CI]	% [95% CI]	% [95% CI]
E. coli
Positive	23 (TP)	2 (FP)	95.8	98.5	92	99.3	0.93
Negative	1 (FN)	135 (TN)	[78.9–99.9]	[94.8–99.8]	[74.4–97.9]	[95.2–99.9]
K. pneumoniae
Positive	6 (TP)	8 (FP)	100	94.8	42.9	100	0.58
Negative	0 (FN)	147 (VN)	[54.07–100]	[90.1–97.7]	[27.6–59.6]	100
P. mirabilis
Positive	3 (TP)	0 (FP)	100	100	100	100	1
Negative	0 (FN)	158 (TN)	[29.2–100]	[97.7–100]	100	100
E. faecalis
Positive	2 (TP)	2 (FP)	100	98.7	50	100	0.66
Negative	0 (FN)	157 (TN)	[15.8–100]	[95.5–99.8]	[20.1–79.8]	100
CTX-M groupe 1
Positive	11 (TP)	0 (FP)	100	100	100	100	1
Negative	0 (FN)	150 (TN)	[71.5–100]	[97.6–100]	100	100

CI, Confidence Interval; TP, true positive, FP, false positive; TN, true negative; FN, false negative; PPV, positive predictive value; NPV, negative predictive value; K, Cohen’s Kappa

ISSN: 1471-2334