[Microbiologic, serologic diagnosis, and genotypification of Helicobacter pylori isolated from biopsies in children and adult people. Molecular detection of the cag pathogenicity island of Helicobacter pylori].

Hp diagnostic is made by invasive methods using gastric biopsy of antrum, for culture and histological study. Non invasive are serology and urea breath test. 152 Hp from 19 children's with acute gastritis (46. 1%); 9 Hp from an adult. There had ampicillin resistance, 27. 4%, claritromicin 21. 8%, metronidazol 58. 4% and tetracycline 31. 5%, the 21 % susceptible to four anti-microbial. RAPD-PCR with 4 primers gave 44 profiles, related with clinical profile. In 7 children, there were two profiles RAPD. Three were similar but different each other. AFLP 23 adults 151 Hp; cagA and vacA genotypes gave unique patterns for each patient. The genes cagA, babA and oipA, secuencing and compared with reported Hp (Genbank); gave high polymorfism. Everything indicates that there are colonization with multiple Hp strains in Mexicans. In 645 sera from 352 children: 36.9% with Hp, the 46. 9% gave him/her anti-shits and 16. 2% antibodies to urease. Adults 293 (89. 1%) with Hp, 78. 9% gave anti-CagA and 59% antibodies to urease. The expression of IL-8 was bigger in infected children that in not infected and more significant in peptic ulcer. Genomic library Cag-PAI revealed 90% (Hp) positive, they had the complete PAI, 2 were incomplete and three negatives. PCR -LiPA LiPA (LineProbe Assay) is suggestive for genotyping assays.