Amoxicillin Resistance in Helicobacter pylori: Studies from Tokyo, Japan from 1985 to 2003

Abstract

H. pylori resistance to AMPC is still rare in Japan, although the percentage of AMPC-I strains has increased over the last 4 years. The frequency of isolation of strains showing true resistance to AMPC may increase in the future, along with an increase in the frequency of isolation of AMPC-I strains.

Role of the Preliminary Susceptibility Testing for Initial and After Failed Therapy of Helicobacter pylori Infection with Levofloxacin, Amoxicillin, and Esomeprazole

“…So far AMO and RIF from this and other studies are those with resistance close to 0%[14]. H. pylori resistance to AMO, despite its wide use in triple therapy worldwide is low, recent reports describe an increased resistance in recent years [15]. RIF, a rifampicin derivative that shows a resistance as low as ampicillin's, is not commonly used due to its potential myelotoxic effect and because it may induce resistance to Mycobacterium tuberculosis.…”

Eradication of <i>H. pylori</i> Infection in Patients Allergic to Penicillin Using Triple Therapy with a PPI, Metronidazole and Sitafloxacin

“…However, the eradication rate associated with this triple therapy is low in patients infected with clarithromycinresistant strains of H. pylori (5). The incidence of clarithromycin-resistant strains has increased in Japan (6). Triple therapy with a PPI, minocycline and metronidazole (7) is also candidate treatment in such cases; however, the eradication rates obtained with this regimen are not always sufficient (6).…”

Correlation between Substitutions in Penicillin‐Binding Protein 1 and Amoxicillin Resistance in Helicobacter pylori

“…The percentage of amoxicillin resistant H. pylori is less than 1% in many regions (15,22,27). However, reports of amoxicillin-resistance in H. pylori have increased recently, and amoxicillin-resistant H. pylori has become the major cause of eradication failure in certain areas (6,16,26). There are two major mechanisms in β-lactam resistance: 1) the presence of β-lactamase that hydrolyzes the β-lactam ring, and 2) alterations in the penicillin-binding proteins (PBPs) which are the targets for β-lactams.…”