Prevalence of Coinfection with Gastric Non-Helicobacter pylori Helicobacter (NHPH) Species in Helicobacter pylori-infected Patients Suffering from Gastric Disease in Beijing, China

BackgroundThe Helicobacter heilmannii sensu lato (H.heilmannii s.l.) group consists of long, spiral-shaped bacteria naturally colonizing the stomach of animals. Moreover, bacteria belonging to this group have been observed in 0.2-6% of human gastric biopsy specimens, and associations have been made with the development of chronic gastritis, peptic ulceration, and gastric MALT lymphoma in humans. Materials and MethodsTo gain insight into the prevalence of H.heilmannii s.l. infections in patients suffering from gastric disease in China, H.heilmannii s.l. species-specific PCRs were performed on DNA extracts from rapid urease test (RUT)-positive gastric biopsies from 1517 patients followed by nucleotide sequencing. At the same time, Helicobacter pylori cultivation and specific PCR was performed to assess H.pylori infection in these patients. ResultsIn total, H.heilmannii s.l. infection was detected in 11.87% (178/1499) of H.pylori-positive patients. The prevalence of H.suis, H.felis, H.bizzozeronii, H.heilmannii sensu stricto (s.s.), and H.salomonis in the patients was 6.94%, 2.20%, 0.13%, 0.07%, and 2.54%, respectively. Results revealed that all patients with H.heilmannii s.l. infection were co-infected with H.pylori, and some patients were co-infected with more than two different Helicobacter species. ConclusionsHelicobacter heilmannii s.l. infections are fairly common in Chinese patients. This should be kept in mind when diagnosing the cause of gastric pathologies in patients. Helicobacter suis was shown to be by far the most prevalent H.heilmannii s.l.species.