Diagnosis of Helicobacter pylori infection: a look into molecular aspects of urea breath test

Abstract

Helicobacter pylori (H. pylori) is a bacterium that selectively colonizes gastric epithelium in more than 50% people over the world. The infection is usually acquired in early childhood and rarely resolved spontaneously; transmission is mostly person to person, and occurs by fecal-oral or oraloral modality. Diagnosis and antibiotic treatment may lead to eradication of H. pylori, improving the prevention and the outcome of gastric and extragastric diseases. Many tests are currently available for the diagnosis of H. pylori infection and the choice depends on several clinical aspects including symptoms, age, indications for testing, concomitant medications and comorbidities.Invasive tests (i.e. endoscopy with histologic assessment) are considered the gold standard, but they are expensive and should be performed only in an appropriate context. The most common noninvasive tests are urea breath test (UBT), stool antigens test and serology. UBT is non-invasive, quick, safe, accurate and cheap. This test is performed mainly with 13 C and is based on the presence of H. pylori urease, an enzyme that converts urea (labelled with an isotope) into CO2. Labelled CO2 is then exhaled and measured by dedicated spectrophotometers. This review analyses with special emphasis UBT, focusing on its molecular aspects.

Management of Dyspepsia and Gastroparesis in Patients with Diabetes. A Clinical Point of View in the Year 2021

“…Since the human stomach is an unfriendly place for microbial survival, H. pylori has developed a repertoire of acid resistance mechanisms which allow the microorganism to overcome the mucous layer. In particular, via the enzyme urease, the bacterium creates a cloud of acid neutralizing chemicals around it, offering protection from the acid [ 14 ]. H. pylori infection is accepted as the most important cause of gastritis and PUD in humans.…”