A Two-Tube Multiplex Reverse Transcription PCR Assay for Simultaneous Detection of Viral and Bacterial Pathogens of Infectious Diarrhea

Table 4

Detection of 13 enteric agents in 122 specimens.

Pathogen	Qiaxcel+^b; reference^a+	Qiaxcel+; reference−	Qiaxcel−; reference+	Qiaxcel−; reference−	Sensitivity	Specificity	Agreement	Kappa value
Norovirus GI	5	0	1	116	83.33%	100%	99.18%	0.9048
Rotavirus	30	5	0	87	100%	94.57%	95.9%	0.8954
Norovirus GII	40	0	5	77	88.98%	100%	95.9%	0.9099
Human astrovirus	13	0	0	109	100%	100%	100%	1
Enteric adenovirus	13	2	0	107	100%	98.17%	98.36%	0.9194
Human bocavirus	5	0	0	117	100%	100%	100%	1
Shigella ^c	4	0	1	117	80%	100%	99.18%	0.8847
Vibrio parahaemolyticus	0	0	0	122
EHEC and EPEC	1	0	0	121	100%	100%	100%	1
Salmonella	3	0	0	119	100%	100%	100%	1
Yersinia	0	0	0	122
Vibrio cholerae	0	0	0	122
Campylobacter jejuni	0	0	0	122

aThe definition of “reference results” was described in “Virus, Strains, and Clinical Samples.” Virus was identified using a commercial ELISA kit, reported multiplex PCR assay, and monoplex PCR followed by sequencing at DD-IVDC [13–16]. All specimens were processed by routine isolation/culture to identify different enteropathogenic bacteria at DD-ICDC. The diarrheagenic Escherichia coli were identified using multiplex real-time PCR assay [17].
^bThe numbers of positive and negative specimens detected by the two-tube assay were indicated as Qiaxcel+ and Qiaxcel−, respectively. The numbers of positive and negative specimens detected by the reference assay were indicated as reference+ and reference−, respectively.
^cThe two-tube assay was not able to distinguish Shigella from EIEC, so Shigella positive detected by the two-tube assay could be Shigella or EIEC. These 5 samples (reference+) were confirmed by sequencing.