Mycobacterium abscessus infection in the stomach of patients with various gastric symptoms

PLoS Negl Trop Dis. 2019 Nov 4;13(11):e0007799. doi: 10.1371/journal.pntd.0007799. eCollection 2019 Nov.

Abstract

Development of gastric diseases such as gastritis, peptic ulcer and gastric cancer is often associated with several biotic and abiotic factors. Helicobacter pylori infection is such a well-known biotic factor. However, not all H. pylori-infected individuals develop gastric diseases and not all individuals with gastric diseases are infected with H. pylori. Therefore, it is possible that other gastric bacteria may contribute to the formation and progression of gastric disease. The aim of this study was to isolate prevalent gastric bacteria under microaerobic condition and identify them by 16S rRNA gene sequence analysis. Analysis of gastric biopsies showed infection of Mycobacterium abscessus (phylum Actinobacteria) to be highly prevalent in the stomachs of subjects included. Our data show that of 129 (67 male and 62 female) patients with gastric symptoms, 96 (51 male and 45 female) showed the presence of M. abscessus in stomach tissues. Infection of M. abscessus in gastric epithelium was further confirmed by imaging with acid fast staining, immunohistochemistry and immunofluorescence. Our imaging data strongly suggested that M. abscessus is an intracellular colonizer residing inside the gastric epithelial cells rather than in macrophages. Additionally, phylogenetic analysis of the mycobacterial hsp65 gene showed that the nearest match to the M. abscessus strains isolated from our study subjects is the M. abscessus strain ATCC 19977. Surprisingly, the subjects studied, the prevalence of M. abscessus infection in stomach is even higher than the prevalence of H. pylori infection. This, to the best of our knowledge, is the first study showing the colonization of M. abscessus in human gastric mucosa among patients with various gastric symptoms. This study could provide usher in a new opportunity to understand the role of less studied gastric bacteria in the development of gastric diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Bacterial Proteins / classification
  • Bacterial Proteins / genetics
  • Biopsy
  • Chaperonin 60 / classification
  • Chaperonin 60 / genetics
  • Child
  • Coinfection
  • Epithelial Cells
  • Female
  • Gastric Mucosa / microbiology
  • Genes, Bacterial / genetics
  • Helicobacter Infections / complications*
  • Helicobacter Infections / epidemiology*
  • Helicobacter pylori / genetics
  • Humans
  • Male
  • Middle Aged
  • Mycobacterium Infections, Nontuberculous / complications*
  • Mycobacterium Infections, Nontuberculous / epidemiology*
  • Mycobacterium abscessus / genetics
  • Mycobacterium abscessus / isolation & purification
  • Phylogeny
  • Prevalence
  • RNA, Ribosomal, 16S / genetics
  • Stomach / microbiology*
  • Stomach / pathology
  • Young Adult

Substances

  • Bacterial Proteins
  • Chaperonin 60
  • RNA, Ribosomal, 16S
  • heat-shock protein 65, Mycobacterium

Grants and funding

The work was supported by a grant from Department of Biotechnology, Government of India to MRP and Department of Science and Technology (ECR/2016/000171) to SC. DC acknowledge Department of Biotechnology for senior research fellowship (DBT/JRF/15/AL/315). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.