Detection of H pylori infection by ELISA and Western blot techniques and evaluation of anti CagA seropositivity in adult Turkish dyspeptic patients

Table 1 Detection of H pylori status by Western blot, ELISA and CagA ELISA of IgA

Patients	H pylori lgA							Toatl
	Western blot n (%)			ELISA n (%)		CagA ELISA n (%)
	+	-	±	+	-	+	-
H pylori (+) (n = 48)	17 (89.5)	24 (80.0)	7 (100)	26 (96.3)	22 (75.9)	16 (94.1)	32 (82.1)	48 (85.7)
H pylori (-) (n = 8)	2 (10.5)	6 (20.6)	0	1 (3.7)	7 (24.1)	1 (5.9)	7 (17.9)	8 (14.3)
Total	19	30	7	27	29	17	39	56

Table 2 Detection of H pylori status by Western blot, ELISA and CagA ELISA of IgG

Patients	H pylori lgG							Toatl
	Western blot n (%)			ELISA n (%)		CagA ELISA n (%)
	+	-	±	+	-	+	-
H pylori (+) (n = 48)	40 (88.9)	1 (50.0)	7 (77.8)	42 (91.3)	6 (85.7)	26 (92.9)	22 (78.6)	48 (85.7)
H pylori (-) (n = 8)	5 (11.1)	1 (50.0)	2 (22.2)	4 (8.7)	4 (57.1)	2 (7.1)	6 (21.4)	8 (14.3)
Total	45	2	9	46	10	28	28	56

Table 3 Results of anti-H pylori ELISA and CagA ELISA of IgA, IgG in dyspeptic patients

	Sensitivity%	Specificity%	PPV%	NPV%	LR +	LR -	Diagnosticaccuracy %
ELISA IgA	54.2	87.5	96.3	24.1	0.62	4.33	58.9
ELISA IgG	87.5	50	91.3	40	1.75	1.75	82.1
CagA ELISA IgA	33.3	87.5	94.1	18	0.38	2.67	41.1
CagA ELISA IgG	54.2	75	92.9	21.4	0.72	2.17	57.1

PPV: Positive predictive value; NPV: Negative predictive value; LR: Likelihood ratio.

Table 4 Anti-H pylori IgG Western blot results of the distribution of different antigens

Antigens	Positive patients (n = 56)	%
p120 (CagA)	28	50
p95 (VacA)	35	62.5
p75	18	32.1
p67 (FSH)	23	41.1
p66 (UreB)	49	87.5
p57 (HSP homolog)	37	66.1
p54 (Flagellin)	24	42.9
p50	24	42.9
p41	28	50
p33	13	23.2
p30	24	42.9
p29 (UreA)	45	80.4
p26	23	41.1
p19 (OMP)	32	57.1
p17	20	35.7