Infection with Helicobacter heilmannii (formerly Gastrospirillum horminis): characterization, epidemiology and therapy

Abstract

Following the discovery of Helicobacter pylori a second Helicobacter species was detected in human gastric mucosa which is now named H. heilmannii. In 1987 Dent et al were the first to describe this spiral organism in the gastric antrum1. McNulty in 1989 extended the report to six further cases and described the bacterium as Gram-negative, up to 7.5 μm long and approximately 0.9 μm wide, twice as large as H. pylori and with up to 12 flagella at each pole2. It closely resembled the spiral bacteria originally described and illustrated by Bizozzero (1893) in the stomach of dogs2. Based on morphology, site of colonization and host species the original name proposed was Gastrospirillum hominis3. Heilmann and Borchard (1991) described in a comprehensive way the histological pattern of the infected gastric mucosa and reported on 37 patients infected with Gastrospirillum hominis4. Subsequently Solnick et al. (1993), by analysis of the 16S ribosomal RNA, proved that Gastrospirillum hominis belongs to the genus Helicobacter5. Based on this finding the name H. heilmannii was proposed instead of Gastrospirillum hominis. Comparison of the 16S rRNA sequence of different H. heilmannii strains, however, shows that the sequences are highly homologous but not identical5,6. It was concluded that the individual strains, which all matched the criteria proposed by McNulty and colleagues, are likely to be several different Helicobacter species. Minor morphological differences in individual H. heilmannii strains were also observed by electron microscopy7. Currently the epithet ‘H. heilmanni’ is used as a working designation for unculturable gastric bacteria lacking an exact microbiological determination.