Serum Pepsinogen Values in Japanese Junior High School Students With Reference to Helicobacter Pylori Infection

Background: Distributions of serum pepsinogen (PG) values were assessed in Helicobacter pylori-infected and non-infected junior high school students (aged 12–15 years) in Japan. Methods: All junior high school students (1,225 in total) in Sasayama city, who were basically healthy, were asked to provide urine and serum samples, which were used to measure urine and serum H. pylori antibodies using ELISA kits and PG values. The subjects, whose urine and serum antibodies were both positive, were considered H. pylori infected. Results: Of the 187 subjects who provided urine and blood samples, 8 were infected, 4 had discrepant results, 4 had negative serum antibody titers no less than 3.0 U/ml, and 171 were non-infected. In the H. pylori non-infected subjects, the median PG I and PG II values and PG I to PG II ratio (PG I/II) were 40.8 ng/mL, 9.5 ng/mL, and 4.4, respectively, whereas in the infected subjects, these values were 55.4 ng/mL, 17.0 ng/mL, and 3.3, respectively (each P < 0.01). In the non-infected subjects, PG I and PG II were significantly higher in males than in females (P < 0.01). Conclusions: The PG I and PG II values were higher, and the PG I/II was lower in H. pylori infected students than in non-infected students. In H. pylori non-infected students, males showed higher PG I and PG II values than females. The distributions of PG values in junior high school students differed from those in adults.