New Helicobacter species in humans

Area of Science:

• Microbiology
• Gastroenterology
• Infectious Diseases

Background:

• Several new Helicobacter species have been identified in human samples (gastric mucosa, feces, liver, gallbladder) over the past decade.
• Gastric Helicobacter heilmannii, related to animal species, causes chronic gastritis and peptic ulcers.
• Intestinal and hepatobiliary Helicobacter species are associated with enteritis, proctitis, septicemia, and inflammatory bowel diseases.

Purpose of the Study:

• To review the isolation and potential roles of non-pylori Helicobacter species in human health.
• To explore the links between animal-borne Helicobacter species and human infections.
• To highlight the diagnostic challenges and suspected pathogenicity of these emerging pathogens.

Main Methods:

• Review of recent studies on Helicobacter species isolation from human and animal sources.
• Analysis of clinical associations and etiological roles of identified Helicobacter species.
• Genetic and morphological comparisons of different Helicobacter species.

Main Results:

• Helicobacter heilmannii is found in dyspepsia patients and linked to peptic ulcers.
• Intestinal species like H. cinaedi and H. pullorum are linked to gastrointestinal issues and septicemia, with known animal reservoirs (hamsters, chickens).
• Hepatobiliary species, notably H. bilis, are found in human gallbladder and animal hosts, while H. pylori is found in human liver.

Conclusions:

• Non-pylori Helicobacter species are increasingly recognized as potential human pathogens.
• Many species are difficult to culture, potentially leading to underdiagnosis.
• Further research is needed to confirm their role in various human diseases, especially inflammatory bowel diseases.