iceA Genotypes of Helicobacter pylori Strains Isolated from Brazilian Children and Adults

Abstract

Data concerning the geographic distribution of iceA alleles are scarce, and information on the association of the gene with the disease is rare and still controversial. Furthermore, no such study has been developed in Brazil, where duodenal ulcer and gastric adenocarcinoma are very common. We investigated, by PCR, the frequency of iceA alleles and cagA status in Helicobacter pylori strains isolated from 142 patients (62 children and 80 adults; 66 female; mean age, 30.0 years; age range, 3 to 78 years) with gastritis, duodenal ulcer, or gastric adenocarcinoma. iceA was identified in bacterium samples obtained from all patients. Eleven (7.7%) of them were infected with multiple strains. Among the patients with nonmixed infection, iceA2 allele was detected in 118 (90.1%). iceA2 allele was associated with ulcer (P ‫؍‬ 0.02) and with carcinoma (P ‫؍‬ 0.001). iceA2 amplicons of 229, 334, or 549 bp were detected, but none of them was associated with the patient's disorder. iceA2 strains were more frequent in patients older than 7 years (P ‫؍‬ 0.001). The gene was also more frequent in strains obtained from males (P ‫؍‬ 0.02). cagA was more common in strains obtained from carcinoma (P ‫؍‬ 0.0008) and ulcer patients (P < 0.006). cagA-positive strains were more frequent in children older than 7 years (P < 0.003). No association between cagA status and sex was found (P ‫؍‬ 0.28). In conclusion, we think iceA should not be used as a reliable marker for predicting the clinical outcome of H. pylori infection.

Prevalence of genotypes in Helicobacter pylori isolates from patients in eastern Turkey and the association of these genotypes with clinical outcome

“…In an attempt to detect association between the cagE gene and PU, In contrast to the results reported in China, Japan, Korea and Netherlands where the iceA1 gene was predominant (16,20,31), the iceA2 gene was detected to be predominant genotype in this study. This result is in agreement with previous reports that the iceA2 gene was found to be prevalent in Brazilian, European and American patients (1,20,22).…”

“…Our results were similar to a previous study (1) (12,19,29) while it was 80-100% in Asian countries (16). We found a higher prevalence (62.1%) of babA2 than the result (53.8%) reported in a previous study (10) in Turkey.…”

A pilot study of Helicobacter pylori genotypes and cytokine gene polymorphisms in reflux oesophagitis and peptic ulcer disease

“…However, iceA1 is much dominant compared to iceA2 in our country, and is consistent with Holland (35), Japan (36) and Hong Kong (37) fi ndings. Studies conducted in USA (38), Columbia (39) and Brazil showed that iceA2 was dominant (40). Peek et al (41) and van Doorn et al (35) reported meaningful association between iceA1 genotype and peptic ulcer, and no statistically signifi cant difference was found in our study between the two groups with refl ux esophagitis and peptic ulcer in terms of iceA1 and iceA2 (IceA1 p=0,556, IceA2 p=0,747).…”

Prevalence of H. pylori strains harbouring cagA and iceA virulence genes in saudi patients with gastritis and peptic ulcer disease

“…Such contradicted results between the iceA genotype and clinical consequences could be explicated by the genetic diversity or differences in the geographic region, which were previously reported for other virulence factors [26]. Moreover, geographic variations in addition to genetic heterogeneity of the host further contribute to the diversity of host responses to particular H. pylori strains and genotypes [27].…”