Table 2 Serum RPR and serum TPPA reactivity associated with S-NS

Serum RPR titers

Serum RPR titers

 Negative

6(3.2)

68(38.2)

1.0 (Ref.)

 1:1

17(9.0)

38(21.3)

5.070

0.002

≥1:1 (vs <1:1)

182(96.8)

110(61.8)

18.752

<0.001

 1:2

21(11.2)

36(20.2)

6.611

<0.001

≥1:2 (vs <1:2)

165(87.8)

72(40.4)

10.562

<0.001

 1:4

18(9.6)

13(7.3)

15.692

<0.001

≥1:4 (vs <1:4)

144(76.6)

36(20.2)

12.909

<0.001

 1:8

16(8.5)

8(4.5)

22.667

<0.001

≥1:8 (vs <1:8)

126(67.0)

23(12.9)

13.696

<0.001

 1:16

24(12.8)

5(2.8)

54.400

<0.001

≥1:16 (vs <1:16)

110(58.5)

15(8.4)

15.325

<0.001

 1:32

26(13.8)

7(3.9)

42.095

<0.001

≥1:32 (vs <1:32)

86(45.7)

10(5.6)

14.165

<0.001

 1:64

35(18.6)

1(0.6)

396.667

<0.001

≥1:64 (vs <1:64)

60(31.9)

3(1.7)

27.344

<0.001

 ≥1:128

25(13.3)

2(1.1)

141.667^†

<0.001

≥1:128 (vs <1:128)

25(13.3)

2(1.1)

13.497

<0.001

Serum TPPA titers

Serum TPPA titers

 ≤1:160^a

2(1.1)

40(22.5)

1.0 (Ref.)

 1:320

5(2.7)

41(23.0)

2.439

0.303

≥1:320 (vs <1:320)

186(98.9)

138(77.5)

26.957

<0.001

 1:640

7(3.7)

32(18.0)

4.375

0.078

≥1:640 (vs <1:640)

181(96.3)

97(54.5)

21.592

<0.001

 1:1280

18(9.6)

34(19.1)

10.588

0.003

≥1:1280 (vs <1:1280)

174(92.6)

65(36.5)

21.607

<0.001

 1:2560

23(12.2)

12(6.7)

38.333

<0.001

≥1:2560 (vs <1:2560)

156(83.0)

31(17.4)

23.117

<0.001

 1:5120

21(11.2)

11(6.2)

38.182

<0.001

≥1:5120 (vs <1:5120)

133(70.7)

19(10.7)

20.236

<0.001

 1:10240

29(15.4)

5(2.8)

116.000

<0.001

≥1:10240 (vs <1:10240)

112(59.6)

8(4.5)

31.316

<0.001

 ≥1:20480

83(44.1)

3(1.7)

553.333^‡

<0.001

≥1:20480 (vs <1:20480)

83(44.1)

3(1.7)

46.111

<0.001