Evaluation of Helicobacter pylori sensitivity to amoxycillin and metronidazole in dyspeptic patients.

We evaluated the "in vitro" sensitivity to amoxycillin and metronidazole of 193 Helicobacter pylori strains isolated from the gastric mucosa of dyspeptic patients. Susceptibility was determined by disc diffusion on agar plates. All the isolates were found to be sensitive to amoxycillin. On the contrary, 12% of the strains isolated from patients never treated for Helicobacter pylori infection and 73% of those isolated from patients who had previously received unsuccessful treatment for Helicobacter pylori infection were found to be resistant to metronidazole. Resistance was more common in women (17%) than in men (4%: p < 0.01) and was not correlated with age. The occurrence of Helicobacter pylori resistance to metronidazole is relatively common in Italy. In vitro testing of Helicobacter pylori sensitivity seems to be important before embarking on treatments aimed at eradicating the bacterium.