Background and Objective: Gastric infection with Helicobacter pylori (H pylori), a strong risk factor for gastric cancer, is highly prevalent in children residing in the Colombian Andes. We aimed to validate the use of the Entero-test to culture and genotype H pylori strains from asymptomatic Colombian children.
Methods: Children (ages 10–15 years, n¼110, 80 of which were H pylori positive by the urea breath test [UBT]) were subjected to the Entero-test, and strings were cultured and/or used for DNA extraction for polymerase chain reaction (PCR). These children had been treated for H pylori in 2007. A second population of children (ages 10–15 years, n¼95),which had not been previously treated, was also subjected to the Entero-test.
Results: Of UBT-positive children in the treated group, 29 of 80 (36%) Entero-test samples were H pylori culture positive; 29 additional string extracts were tested by PCR for the H pylori virulence factors cagA and vacA. PCR from cultures and extracts yielded a sensitivity of 74% and specificity of 87%. In the untreated group, 16 of 94 UBT-positive children (17%) produced Entero-tests that were culture positive. Fifty-eight of 94 (62%) string extracts were PCR positive for cagA and/or vacA. In previously treated children, H pylori strains were more often the less virulent vacA s2 (P¼0.001), m2 (P¼0.006), and i2 genotypes (P¼0.039).
Conclusions: The Entero-test may be used as a noninvasive test to detect
H pylori in asymptomatic children residing in high-risk areas for gastric
cancer. Treatment of H pylori in children was associated with less virulent
genotypes.