Journal of Carcinogenesis & Mutagenesis

Abstract

False Sero-Negative Results for Helicobacter Pylori Infection Indicate Increased Risk of Severe Atrophic Gastritis in Japanese Patients

Hitomi Ichikawa, Mitsushige Sugimoto, Mihoko Yamade, Takahiro Uotani, Shu Sahara, Takuma Kagami, Yasushi Hamaya, Moriya Iwaizumi, Satoshi Osawa, Ken Sugimoto, Hiroaki Miyajima and Takahisa Furuta

Background/objective: H. pylori infection is commonly diagnosed using an anti-H. pylori IgG antibody test. However, a proportion of results are falsely sero-negative. We investigated characteristics of patients falsely seronegative for H. pylori in relation to gastric atrophy.
Methods: H. pylori infection (Hp+ or Hp-) was determined based on culture test, rapid urease test (RUT), and polymerase chain reaction (PCR) test in 280 outpatients. Anti-H. pylori antibody titers ≥ 10 U/ml were diagnosed as sero-positive for H. pylori (IgG+), while those <10 U/ml were sero-negative (IgG-). Serum pepsinogen (PG) I/PG II ratios were calculated as a serological marker of gastric atrophy. Endoscopic gastric mucosal atrophy was also assessed according to the Kimura-Takemoto classification system.
Results: The mean PG I/PG II ratio in each group was as follows: Hp-/IgG- (4.99 ± 1.04, n=10), Hp+/IgG+ (2.59 ± 1.51, n=240), Hp-/IgG+ (5.65 ± 2.72, n=4) and Hp+/IgG- (3.02 ± 2.61, n=26). The mean serum PG I/PG II ratio in the Hp+/IgG- group was lower than those of Hp-/IgG- and Hp-/IgG+ groups (P=0.028 and 0.072). Incidence of severe gastric mucosal atrophy in the Hp+/IgG- group was highest of the four groups.
Conclusions: Individuals falsely sero-negative for H. pylori infection is at increased risk of severe atrophic gastritis, which is well known as precancerous lesion.