This paper reports a 67-year-old man who was diagnosed as having gastric ulcer (stage A1) in January 1995. The ulcer recurred repeatedly despite treatments using PPI and other drugs. H pylori infection was detected by anti-Hp Ig-G antibody (2＋) , RUT (＋) , microscopy (＋) , and the 13CUBT (46.2‰) , so eradication therapy was performed in May 1996. The therapy consisted of a PPI (30mg/day of lansoprazole) , AMPC (1,500mg for 2 weeks) , and CAM (400mg for 2 weeks) . Although the ulcer healed to stage S1 by 4 weeks after completion of therapy, eradication was concluted to have failed because the 13CUBT was result 8.7‰ after 4 weeks and 17.5‰ after 8weeks.
Subsequently, an H2-blocker was administered and the ulcer healed to stage S2 in October 1997 (17 months after eradication therapy) . The 13CUBT value was 1.9‰, and RUT, microscopy, and serum anti-Ig-G antibody were all negative. In this patient, H pylori was considered to have been spontaneously cleared because he did not take medications that could eliminate the organism after the eradication therapy, except for 1,500mg of AMPC for 5 days to treat an acute upper respiratory tract infection.
