Comparison of gastric juice soluble triggering receptor expressed on myeloid cells and C-reactive protein for detection of Helicobacter pylori infection

Background and aim Triggering receptor expressed on myeloid cells (TREM-1) is a receptor on phagocytes that is triggered by infectious agents. The soluble form of it (sTREM-1) can be elevated in gastric juice by Helicobacter pylori (H. pylori) infection of gastric mucosa. The aim of this study was to compare the diagnostic values of sTREM-1 and C-reactive protein (CRP) for detection of H. pylori infection in gastric mucosa. Methods In this diagnostic accuracy study on cases who underwent endoscopy from March 2015 to July 2016 in Shahid Beheshti Hospital, Kashan, Iran, gastric juice sTREM-1 and CRP concentrations were measured by enzyme-linked immunosorbent assays (ELISA) and their diagnostic values were compared to detect H. pylori infection. Gold standard test was histopathology. Data were entered into SPSS software version 16. Statistical analysis was made by Kolmogorov-Smirnov, Chi-square, Independent-samples t-test, Kruskal-Wallis, Mann-Whitney U, Pearson product-moment correlation, Receiver operating characteristic curve (ROC), Brier score, Nagelkerke R square and scaled reliability test. Results Of a total of 160 cases, 81 (50.6%) were H. pylori-positive based on pathology. The level of sTREM-1 in H. pylori-positive patients was significantly higher than H. pylori-negative patients (p=0.000), but no significant difference between CRP concentrations was shown between groups (p=0.7). Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and accuracy of sTREM-1 were 82%, 75%, 3.3, 0.25, 78% and for CRP were 62%, 40%, 1.02, 0.98, 51% respectively for diagnosis of H. pylori infection. True positive and negative rates were 66 (81.5%) and 59 (74.7%) for sTREM-1 and 50 (61.7%) and 31 (39.2%) for CRP. The levels of sTREM-1 and CRP were not significantly different between endoscopic finding groups (p=0.97, p=0.2 respectively). Conclusion Despite CRP, sTREM-1 was a relatively acceptable indicator of H. pylori infection of gastric mucosa.