To investigate the changes in serum anti-Helicobacter pylori IgG antibody (HP Ab), pepsinogen I (PG I), pepsinogen II (PG II), and pepsinogen I/II ratio (PG I/II) after eradication therapy of Helicobacter pylori (HP), we studied 78 patients with HP-positive peptic diseases. They received combination therapy (proton pump inhibitor + amoxicillin: n = 17, proton pump inhibitor + amoxicillin + clarithromycin: n = 61). In the 68 patients in whom HP was eradicated, HP Ab, PG I, and PG II decreased and PG I/II increased significantly after eradication. Especially, the decrease in PG II and the increase in PG I/II were rapid and remarkable, found 2 months after the beginning of eradication therapy, and then continued. On the other hand, in the patients in whom HP was not eradicated, HP Ab and PG I/II did not change significantly, while PG I and PG II temporarily increased at the end of administration of proton pump inhibitor. In conclusion, it seems that the measurement of PG II and PG I/II is useful for the early detection of HP eradication.
Amoxicillin Anti-Bacterial Agents