Published online Sep 15, 1996. doi: 10.3748/wjg.v2.i3.152
Revised: July 25, 1996
Accepted: August 16, 1996
Published online: September 15, 1996
AIM: The relationship between Helicobacter pylori (Hp) and gastric epithelia in chronic gastritis and in peptic ulcers was studied by transmission electron microscopy (TEM).
METHODS: Seventy-five patients were screened for Hp. Gastric antral biopsy specimens were fixed in glutaraldehyde and treated with tannic acid before OsO4 staining. Samples were routinely processed for TEM studies (at least four semi-thin sections oriented for ultrathin sections in each sample).
RESULTS: The bacilli were detected by TEM within the gastric mucosa in 53 of 55 patients infected with Hp. Ultrathin sections revealed clear glycocalyx by which the bacillus was connected to the epithelium. As the bacilli colonized, the adjacent mucous cells degenerated. They were characterized by erosion of the juxtaluminal cytoplasm, vacuolation or blebbing, and desquamation of the cell membrane. The bacilli located in the lumen attracted neutrophils, which migrated into intercellular space of the epithelia or into the lumen to begin phagocytosis of Hp.
CONCLUSION: The sensitivity and specificity of TEM diagnosis is 96% and 95%, respectively. Tannic acid is suitable for the preservation of the glycocalyx of a cell. The colonized bacilli, usually with the wide periplasm, contributed to the degeneration of epithelia, including mucous neck cells. If Hp infection persists, the degeneration and regeneration of mucous neck cells occurs alternatively. Ultimately the generative stem cells were damaged, and as a result chronic atrophic gastritis could occur.