Discrimination of False Negative Results in RT-PCR Detection of SARS-CoV-2 RNAs in Clinical Specimens by Using an Internal Reference

Figure 7个 Table 2个

Patient	Test (n)	Ct value of RPP30
Patient	Test (n)	≤ 21.53				21.53–24.47				> 24.47
SARS-CoV-2 RNA (N or ORF1ab region)		+/+	±	−/−		+/+	±	−/−		+/+	±	−/−
P1	4	1				1						2
P2	6					1	3					2
P3	11	1				3	4				1	2
P4	5					1	2					2
P5	8	3				1	2					2
P6	7	1				3	1					2
P7	7	4				2						1
P8	10	2				3	5
P9	12	2					5	1			2	2
P10	5	2				1		1				1
P11	3	2										1
P12	7	3				2	1	1
P13	7	4				2						1
P14	13	5					5					3
P15	4	1	1			1						1
Total	109	31	1			21	28	3			3	22

Table 1. Correlation between Ct values of RPP30 and detection results of SARS-CoV-2 RNA in sputums

Patient	Test (n)	Ct value of RPP30
Patient	Test (n)	≤ 25.53				25.53–27.48				> 27.48
SARS-CoV-2 RNA (N or ORF1ab region)		+/+	±	−/−		+/+	±	−/−		+/+	±	−/−
W1	7	2					3					2
W2	14						4	1				9
W3	5					1	1	1				2
W4	6	1					2	1				2
W5	6	1					2					3
W6	9	1	1			1	1				1	4
W7	7	1					1			1		4
W8	5	2						1			1	1
W9	10	2				1	1					6
W10	3					1	1					1
Total	72	10	1			4	16	4		1	2	34

Table 2. Correlation between Ct values of RPP30 and detection results of SARS-CoV-2 RNA in throat swabs