[Approach to Patients with Consecutive Eradication Failure].

() is associated with various gastrointestinal disorders, such as gastritis, peptic ulcers, mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Therefore, the International Agency for Research on Cancer, a specialized cancer agency of the World Health Organization, categorizes as a definite gastric carcinogen (group I). eradication is a major challenge both medically and socioeconomically in countries with high prevalence of and gastric cancer. However, the efficacy of first-line clarithromycin-containing triple therapy and second-line bismuth-containing quadruple therapy continues to decline worldwide including in Korea. The role of salvage therapy is being recognized globally; however, the exact salvage therapy which is useful in daily clinical practice remains unestablished. In this review, factors associated with eradication failure will be discussed. Furthermore, eradication regimens that may be useful as salvage therapies based on Korean guidelines, Maastricht VI/Florence consensus report and previous research are summarized.