TABLE 4.

Performance of the real-time PCR in predicting antimicrobial resistance to four antibiotic classes directly from Neisseria gonorrhoeae-positive clinical specimens with paired N. gonorrhoeae isolates^a

Reaction	Associated antibiotic	No. of isolates with the following result:					Sensitivity (95% CI)b	Specificity (95% CI)b
		TP	FP	FN	TN	Total
penA Asp345del ± penA Gly545Ser	ESCs	1c	17d	0	76	94	1.00 (0.03, 1.00)	0.82 (0.72, 0.89)
23S rRNA C2611T and/or 23S rRNA A2059G	AZM	1	1	0	92	94	1.00 (0.03, 1.00)	0.99 (0.94, 1.00)
gyrA Ser91Phe	CIP	41	1	0	52	94	1.00 (0.91, 1.00)	0.98 (0.90, 1.00)
16S rRNA C1192T	SPC	0	2	0	92	94	NA	0.98 (0.93, 1.00)

^aCI, confidence interval; TP, true positive; FP, false positive; FN, false negative; TN, true negative; ESCs, extended-spectrum cephalosporins; AZM, azithromycin; CIP, ciprofloxacin; SPC, spectinomycin; NA, not applicable.

^bSensitivity and specificity were calculated on the basis of the susceptibility phenotype (MICs) of the paired culture isolates.

^cThis isolate harbored a penA mosaic X allele and was correctly identified as ESC resistant by the penA Ala345del reaction.

^dThree isolates were correctly predicted to harbor a mosaic penA allele on the basis of the molecular characterization but were susceptible to ESCs.