Antimicrobial Susceptibility and Mutations Involved in Clarithromycin Resistance in Helicobacter pylori Isolates from Patients in the Western Central Region of Colombia

Resistance to metronidazole, clarithromycin, and amoxicillin (amoxicilline) was found in 82, 3.8, and 1.9% of 106 Helicobacter pylori isolates, respectively. No tetracycline-resistant isolates were found. In all of the clarithromycin-resistant isolates, only one point mutation was present, either A2143G or A2142G. Our results indicate that metronidazole should not be included in the empirical treatment of H. pylori infection in this region. Helicobacter pylori is the major cause of chronic gastritis and peptic ulcer disease (21). The prevalence of H. pylori infection in dyspepsia patients in Colombia is higher than 80 % (20). Resistance to antimicrobials is of particular concern as a major cause of the failure to eradicate this pathogen (5, 23). Treatment consists of triple therapy with a proton pump inhibitor plus two antibiotics (1, 27). In Colombia, the most commonly prescribed antibiotics are amoxicillin (amoxicilline), clarithromycin, and metronidazole (11). Many reports have indicated that the prevalence of resis