Epidemiology and Diagnostics of Helicobacter pylori Infection

Ieva Zailskaitė1, Milda Gylytė1,  Aistė Čemerkaitė1

1Lithuanian University of Health Sciences, Medical Academy, Faculty of Medicine

Abstract

Helicobacter pylori is a gram – negative bacterium, that infects approximately 4,4 billion individuals, which is up to 50% of the world‘s population. During 2005 – 2006 older than 55 years old patients in Lithuania were endoscopically investigated for the dyspeptic symptoms, 69,7 % of them were infected by H. pylori. This bacterium colonizes the human stomach and is responsible for peptic ulcers, adenocarcinoma, stomach cancer and MALT lymphoma.          The diagnostic methods in case of H. pylori infection are divided into two types: invasive, including endoscopic examination with the cultivation of bacteria on a medium, rapid urease test, histopathological examination or molecular diagnostics, and non-invasive methods, including breath tests, examination of stool for the presence of antigens, serologic biomarkers. Urea breath test is suitable for detecting H. pylori infection of dyspeptic patients who have comorbidities that increase their risk for endoscopy. Stool antigen test is a non-invasive test used to detect active H. pylori infection and is best suited for children. Serological tests are essential for the primary selection of H. pylori infection. Invasive tests are first choice diagnostic methods, when other upper endoscopy indications are present for the patient. The rapid urease test from gastric biopsies is the first choice test for H. pylori diagnostics. This test is fast, inexpensive, reliable, and simple. It provides the results in a few hours. Histology is considered as the gold standard in the direct diagnosis of H. pylori. This method allows for evaluation of H. pylori infection complications – inflammation, metaplasia, malignancy, but this method is quite expensive and requires for trained personnel for sample processing and interpretation. Culturing of gastric biopsy samples is not a routine method for detecting H. pylori. Bacterial culture is carried out mainly for scientific research and when the prior antibiotic-therapy has failed to detect an appropriate bacterium, this method allows determine antibiotic susceptibility.

Keywords: Helicobacter pylori, epidemiology, diagnostics, invasive, noninvasive