High prevalence of clarithromycin resistance and cagA, vacA, iceA2, and babA2 genotypes of Helicobacter pylori in Brazilian children.

We isolated 45 Helicobacter pylori strains from 217 child patients. Resistance to clarithromycin, metronidazole, amoxicillin, and tetracycline was detected in 27%, 13%, 4%, and 0% of strains, respectively. The A2143G mutation was the most prevalent (67%) among clarithromycin-resistant strains.