Helicobacter heilmannii Colonization Is Associated with High Risk for Gastritis.

Introduction: We aimed to study potential associations between colonization by four common non-pylori Helicobacter species and gastroduodenal diseases by comparing samples from patients infected with H. pylori with samples from non-infected subjects.

Materials And Methods: Patients (n = 190) who were subjected to upper gastrointestinal endoscopy because of gastroduodenal conditions were enrolled in this cross-sectional study. Antral biopsy samples were taken from patients in two major hospitals (Mehrad and Imam-Hossein) in Tehran, Iran, during 2017-2018. DNA was isolated from the biopsy specimens, and PCR amplification was used to identify the Helicobacter species by using their corresponding specific primer sets.

Results: Out of 120 cases positive for H. pylori, 46 (38%) were patients with gastritis, 23 (19%) with duodenal ulcer, 11 (9%) with gastric cancer, and 40 (33.3%) with gastric ulcer. Overall, 70 (36%) patients were negative for H. pylori. H. pylori cases were uninfected by any of the other tested Helicobacter species. Among the 70 patients without H. pylori, 34 had gastritis-31 (94%) of these were positive also for H. heilmannii (p = 0.001, Odds Ratio: 51.6; 95% Confidence Intervals: 11.8-225.6). We did not find any patient carrying mixed Helicobacter infections with any non-pylori Helicobacter species in this cohort.

Conclusions: Given our evidence about the possibility of involvement of H. heilmannii in patients suffering from gastritis and nonexistence of mixed non-pylori Helicobacter infections, bacteriological testing of subjects negative for H. pylori becomes clinically relevant and important.