The coccoid forms of Helicobacter pylori. Criteria for their viability

Epidemiol Infect. 1993 Dec;111(3):483-90. doi: 10.1017/s0950268800057216.


The fact that Helicobacter pylori can revert to a coccoid form has stimulated speculation about its role in transmission and as a possible cause of reinfection in duodenal ulcer disease. Bismuth subcitrate (32 micrograms/ml), bismuth subsalicylate (64 micrograms/ml), amoxicillin (0.05 micrograms/ml) and erythromycin (4 micrograms/ml) inhibited the growth of H. pylori and stimulated the formation of basically respiring but non-culturable coccoid structures. The presence of polyphosphates as energy and phosphorus source permits a certain level of endogenous metabolism to preserve RNA and DNA, as well as structural components like cell wall, cell membrane and cytoplasma for at least 3 months. However, the applied standard laboratory methods were insufficient for regrowth of H. pylori out of the coccoid form.

MeSH terms

  • DNA, Bacterial / biosynthesis
  • Helicobacter pylori / genetics
  • Helicobacter pylori / growth & development*
  • Helicobacter pylori / ultrastructure
  • Humans
  • Immunohistochemistry
  • Microscopy, Electron
  • Spectrum Analysis


  • DNA, Bacterial