An Overview of Helicobacter Pylori and Diagnostic Methods

Author(s): Rahimkhani M, Mordadi A

Helicobacter pylori are a gram negative, spiral, micro-aerophilic and slow-growing organism with a length of 3 and a diameter of about half a micrometer. The bacterium also produces some enzymes, the most important of which are oxidase, catalase and urease. More than half of the world's people are infected with this bacterium.

The bacteria are the main cause of diseases such as gastric ulcer and gastric and intestinal complaints. The incidence of infections with this bacterium in the countries of Europe and North America are 10 times higher than in other countries. Helicobacter pylori are basically a spiral bacterium, but it can also be transformed into a spherical shape that can also be survived and pathogenic and connects to the gastric mucosa.

Several laboratory methods are available including invasive and non-invasive methods. Each test has its own characteristics, but is not complete on its own. Usually, several tests are used together, but this depends on our goal of testing. Invasive method is endoscopic biopsy of gastric mucosa and rapid urease test on biopsy sample. Noninvasive methods are included, serologic tests (IgM, IgG & IgA), breath urease test and examination of H. pylori antigens in the stool. In specialized laboratories PCR is also used to identify bacteria.

Regarding the prevalence of gastrointestinal diseases and the lack of adequate knowledge in today's societies about this bacterium, this study was conducted with the aim of reviewing Helicobacter pylori and different diagnostic methods.