Concordance of the rapid urease test and the histopathology report in detecting H. pylori infection in a bariatric population. A retrospective cohort study

Introduction
Bariatric surgery has become one of the most prominent treatment modalities for obesity. Esophagogastroscopy (EGD) with Helicobacter pylori testing is a part of the preoperative work-up. There are no guidelines defining the preferred method of detecting H. pylori.

Aim
The study aimed to establish the prevalence of H. pylori infection among bariatric patients and compare the two commonly used invasive diagnostic tests: the rapid urease test (RUT) and histopathology. The secondary aim was to evaluate the usefulness of EGD and histology in diagnosing gastritis.

Material and methods
A retrospective analysis was performed among patients with obesity undergoing bariatric surgery. As part of the preoperative work-up, EGD was performed with RUT using the Lencomm GOLD Hp dry CLO test and a histopathology sample taken from the gastric antrum and body. The Cohen’s kappa inter-rated reliability test was used for concordance calculation.

Results
280 patients were analyzed, of whom 98 (35.00%) were diagnosed with H. pylori infection with at least one method. The Cohen’s kappa inter-rated agreement between the RUT and histology sampling was 0.80. Macroscopic gastritis was present in 76 (77.56%) of infected patients. Histology showed microscopic gastritis in 99 (99%) of those patients. 161 (57.50%) of the study group were diagnosed with macroscopic gastritis; among these, histology confirmed inflammation in 119 (73.91%).

Conclusions
There is a good concordance between RUT and histopathology diagnosis of H. pylori among the bariatric population. Additionally, there is a low accuracy rate in EGD assessments of gastric mucosa changes.