TABLE 2.

Performance of TP-PA and INSTI Multiplex for the detection of Treponema pallidum antibodies in patients with primary syphilis

Sample	T. pallidum PCR resulta	TP-PA resultb	RPR titerc	INSTI Multiplex T. pallidum line result
A	Positive	Nonreactive	Nonreactive	Nonreactive
B	Positive	Nonreactive	Nonreactive	Nonreactive
C	Positive	Reactive	1:1	Reactive
D	Positive	Reactive	1:2	Reactive
E	Positive	Reactive	1:4	Nonreactive
F	Positive	Reactive	1:4	Reactive
G	Positive	Reactive	1:8	Reactive
H	Positive	Reactive	1:8	Reactive
I	Positive	Reactive	1:16	Reactive
J	Positive	Reactive	1:16	Reactive
K	Positive	Reactive	1:16	Reactive
L	Positive	Reactive	1:32	Reactive
M	Positive	Reactive	1:64	Reactive
N	Positive	Reactive	1:64	Reactive

^a“Positive” indicates that T. pallidum DNA was detected in swabs from genital lesions.

^b“Reactive” indicates the presence of antibodies to T. pallidum. TP-PA, Treponema pallidum particle agglutination.

^cA higher titer indicates a more recent infection. RPR, rapid plasma reagin.