Antibiotic susceptibility in Helicobacter pylori strains isolated from Venezuelan patients with duodenal ulcer

Abstract

Helicobacter pylori antimicrobial drug resistance has appeared as an important cause of treatment failure. Samples were collected from 38 H. pylori infected patients with duodenal ulcers from the Gastroenterology Service of the “Hospital Vargas”, Caracas, Venezuela (2009-2011) and were processed by the E-test method. The 94.8% isolates were sensitive to clarithromycin and erythromycin with MIC values of <0.5 mg/L and < 2 mg/L respectively. The 92.2% of the strains had a tetracycline MIC under 1 mg/L and 37% of the sensitive H. pylori strains had a metronidazole MIC of <8 mg/L. Metronidazole resistance occurred in 24/38 strains (63.1%), while resistance to erythromycin was found in 2/38 strains (5.2%), clarithromycin in 2/38 (5.2%), and tetracycline in 3/38 (7.8%) of the isolates. None of the strains was found to be resistant to amoxicillin. We observed 6/38 (15.8%) multi-drug resistance of H. pylori isolates in different combinations.