Antimicrobial susceptibility of Helicobacter pylori isolated from gastric biopsies in dyspeptic patients.

The objective of this study was to evaluate the prevalence of antimicrobial resistance in Helicobacter pylori isolated from the antrum and corpus of dyspeptic patients in Khon Kaen, Thailand, and to compare the antimicrobial susceptibility patterns of H. pylori isolated from the antrum and corpus in individual patients. Antimicrobial susceptibility was determined by disk diffusion, studying susceptibility to metronidazole, clarithromycin, amoxicillin, erythromycin, ciprofloxacin, and tetracycline. The H. pylori resistant rate to at least one of the six antimicrobial agents tested was 37%. The resistance rates were 30.2% for metronidazole, 9.2% for ciprofloxacin, 5% for clarithromycin, 2.4% for amoxicillin, and 1.7% for erythromycin and tetracycline. Single, double, and more than double antimicrobial resistances were found in 27.7, 6.7 and 2.5%, respectively. Antimicrobial susceptibility testing revealed 11 antibiotypes. The most common antimicrobial susceptibility pattern found was sensitivity to 6 antimicrobial agents (63%). H. pylori antimicrobial resistance in specimens isolated from the antrum and corpus were nearly equivalent, 37.3% (22/59) and 36.7% (22/60), respectively. Most of the H. pylori specimens isolated from the antrum and corpus in individual patients were identical (87.7%).

Detection of H. pylori in dyspeptic patients and correlation with clinical outcomes.

The objectives of this study were to evaluate the methods used to diagnose Helicobacter pylon infection in gastric biopsies, and to evaluate the correlation between H. pylori infection and clinical outcomes. Gastric biopsies, obtained from 210 patients, were evaluated for H. pylori by culture, a commercial rapid urease test (RUT, Pronto Dry) and histological examination. A true positive result was either the culture or both the RUT and histological examination were positive. The results showed a H. pylori infection rate of 44.3% (93/210). The sensitivities, specificities, positive predictive values and negative predictive values were 88.2, 100, 100, and 91.4 % by the culture; 95.7, 98.3, 97.8, and 96.6% by RUT; and 96.8, 59.8, 59.8, and 65.7% by histological examination, respectively. The prevalences of H. pylori in non-ulcer dyspepsia (NUD), peptic ulcer dyspepsia (PUD) and gastric cancer (GCA) patients were 41.2, 57.9 and 70.6%, respectively. The chi-squared-test showed that GCA patients were significantly more frequent infected with H. pylori than NUD patients (p<0.05). Our study indicates that the RUT method was highly sensitive, specific and appropriate for routine clinical use.