Does the antibody production ability affect the serum anti-Helicobacter pylori IgG titer?

Table 4 Findings of the followed-up subjects n (%)

	Successful H. pylori eradication (n = 25)	Persistent H. pylori infection (n = 16)	P value	Before eradication	After eradication	P value (Z1)	Initial	Follow-up	P value
Initial test findings
Age (yr, mean ± SD)	52.3 ± 7.9	55.3 ± 12.7	0.351
Gender (male:female)	15:10	9:07	1
Degree of H. pylori infiltration on biopsy (mild:moderate: marked)	4:05:16	2:04:10	0.907
Anti-H. pylori IgG titer (AU/ mL, mean ± SD)	3.00 ± 1.17	3.17 ± 0.92	0.632
PG I level (ng/mL, mean ± SD)	79.3 ± 31.7	64.9 ± 23.4	0.126
PG II level (ng/mL, mean ± SD)	23.4 ± 8.5	18.9 ± 9.1	0.117
PG ratio (mean ± SD)	3.5 ± 1.1	3.9 ± 1.5	0.419
Presence of corpus gastric atrophy as reflected by serum PG assay	4 (16.0)	2 (12.5)	0.566
HBsAb titer (mIU/mL, median with ranges)	72.2 (3.1-1000)	170.3 (3.1-1000)	0.632
Positive HBsAb assay	16 (64)	12 (75)	0.513
Duration of the follow-up period (months, median with ranges)	18.1 (2-61)	20.2 (6-41)	0.887
Subjects with successful H. pylori eradication (n = 25)
Follow-up test findings
Degree of H. pylori infiltration on biopsy (none:mild:moderate: marked)				0:4:5:16	25:0:0:0	< 0.001 (-4.520)
Anti-H. pylori IgG assay (negative:lowest:middle:highest quartiles)2				3:2:14:6	20:4:1:0	< 0.001 (-4.171)
PG I level (ng/mL, mean ± SD)				79.3 ± 31.7	54.2 ± 14.5	0.028 (-2.201)
PG II level (ng/mL, mean ± SD)				23.4 ± 8.5	7.0 ± 1.7	0.028 (-2.201)
PG ratio (mean ± SD)				3.5 ± 1.1	7.8 ± 1.6	0.028 (-2.200)
HBsAb titer (mIU/mL, median with ranges)				72.5 (3.1-1000)	18.4 (3.1-1000)	0.308
Subjects with persistent H. pylori infection (n = 16)
Follow-up test findings
Degree of H. pylori infiltration on biopsy (none:mild:moderate: marked)							0:2:4:10	1:3:2:10	0.335
Anti-H. pylori IgG assay (negative:lowest:middle:highest quartiles)2							1:0:8:7	0:2:7:7	1.18
PG I level (ng/mL, mean ± SD)							64.9 ± 23.4	71.8 ± 35.2	1
PG II level (ng/mL, mean ± SD)							18.9 ± 9.1	21.4 ± 10.3	0.779
PG ratio (mean ± SD)							3.9 ± 1.5	3.6 ± 0.8	0.395
HBsAb titer (mIU/mL, median with ranges)							170.3 (3.1-1000)	202.1 (3.1-1000)	0.314

¹Z values are shown for the significant variables using Wilcoxon signed rank test;

²The serum anti-H. pylori IgG titer was compared using the quartiles because it was measured using the Vidas H. pylori IgG assay until 2012, and using the Chorus H. pylori IgG assay thereafter. SD: Standard deviation; HBsAb: Hepatitis B surface antibody; PG: Pepsinogen; H. pylori: Helicobacter pylori.