[Antibiotic resistance of Helicobacter pylori in an infectious disease referral center].

OBJECTIVE

To estimate the frequency of H. pylori clinical isolates resistant to six commonly used antimicrobials.

DESIGN

Cross-sectional observational study.

SETTING

A tertiary-referral health care institution in Mexico City.

PARTICIPANTS

31 isolates of H. pylori from 31 patients with chronic antral gastritis were obtained from gastric mucosal biopsy specimens.

MAIN OUTCOME MEASURE: The Minimum Inhibitory Concentration (MIC) to ampicillin, amoxycillin, tetracycline, doxycycline, metronidazole and to colloidal bismuth subcitrate was determined by the agar plate dilution test.

RESULTS

All isolates showed to be susceptible to the former four antibiotics but only in 46% and 55% growth was inhibited by 8 micrograms/mL and 16 micrograms/mL of metronidazole, respectively. All isolates were inhibited by < or = 128 micrograms/mL of bismuth. A 50% increase in the percentage of metronidazole-resistant isolates (MIC > or = 8 micrograms/mL) between 1988 to 1992 was observed.

CONCLUSION

There is a need of future studies in our setting aimed at assessing the cost/effectiveness of diverse H. pylori-associated peptic ulcer treatment options.