Helicobacter pylori-associated gastritis

Abstract

The relationship between Helicobacter pylori, histological gastritis, symptoms and endoscopic findings were investigated in patients referred for investigation of upper gastrointestinal symptoms. Infection was present in 47% of patients and was strongly associated with histological gastritis but not with symptoms or endoscopic appearance. A human ingestion study was undertaken showing that Helicobacter pylori is capable of infecting normal human gastric mucosa causing a short-lived clinical illness, altered gastric pH and histological gastritis. Seroconversion was observed and a decline in antibody levels followed eradication of infection. Treatment studies showed that the dosing schedule and formulation of colloidal bismuth subcitrate are important factors determining response to therapy. Of the tests used to detect H. pylori microbiological methods were the most sensitive. Histological detection of infection is best when multiple sections from two biopsies are examined. An ELISA assay was developed and serology suggested that H. pylori infection was common in certain occupational and racial groups within New Zealand. Eradication of H. pylori significantly reduces the relapse rate of healed duodenal ulcers. Detailed examination of postmortem stomachs showed that infection and histological gastritis is widespread within the stomach. Histological gastritis in patients taking non-steroidal anti-inflammatory drugs is due to H. pylori infection not the non-steroidal agents themselves. The close ecological association between H. pylori and gastric epithelium was shown by detecting H. pylori on gastric epithelium in a Meckel’s diverticulum. No evidence of H. pylori or H. mustelae infection was found in a group of New Zealand ferrets. Helicobacter pylori is almost universal in patients undergoing endoscopy in Fiji and Tonga. Finding urease positive tightly spiral organisms in two patients and showing that infection and gastritis resolved following colloidal bismuth subcitrate treatment indicates that H. pylori is not the only organism capable of causing histological gastritis in man.