Objective: To study the epidemiology, microbiology, pathogenicity, diagnosis and therapy of Helicobacter heilmannii (Hh) infection.
Methods: Morphological methods, such as Gram staining of gastroscopic biopsy smears, Giemsa staining of histological slides and scanning electromicroscopy(SEM), and biochemistry techniques such as urease test(CLO), 14C urea breath test(UBT) were used to identify Hh infection in natural populations. The 16S rRNA gene of 4 strains of Hh were amplified, sequenced and analysed, using bacterial universal and Helicobacter genus-specific primers.
Results: Twenty cases of Hh infection were found in 992 peoples with the positive rate of 2.0%. There existed the phenomena of intrafamily cluster of Hh infection. 14 case of the gastic tissues were CLO positive and 3 cases of these patients were UBT positive, the bacterium cannot be isolated in vitro. Sporadic invasion of lymphocyte/plasmic cell were found in gastric mucosa with Hh infection. Formation of lymph follicles and invasion of neutrophlic cell could be found too. The "old triple therapy" regimen could eradicate Hh easily. The homology of 16S rRNA gene among 4 strains was between 98.7%-99.7%, and can not be devided into two subtypes. The homology between Hh and H. felis or Hp were 95.6%-96.5% and 96.4%-97.1%, respectively.
Conclusion: The prevalence of Hh in southern China is higher than that reported abroad. There may exist animal to person and person to person transmission mechanisms. Hh should be a new Helicobacter with lower activity of urease and weaker pathogenicity when compared with H. pylori. The infection of Hh is easy to eradicate through drug therapy.