Serologic detection of CagA positive Helicobacter pylori strains predicts the presence of peptic ulcer in young dyspeptic patients

Background: Helicobacter Pylori infection has been strongly associated with upper gastrointestinal (GI) disease, especially duodenal ulcer. Endoscopy or contrast radiography is needed to diagnose and appropriately manage peptic ulcer disease. These diagnostic procedures, however, are time consuming and expensive; endoscopy is invasive and contrast radiography cannot help in the diagnosis of H pylori infection. Our aim was to examine in a prospective study the relation between serologic detection of cytotoxic associated gene (CagA) H pylori strains and endoscopic findings among young dyspeptic patients to determine whether this noninvasive test can help differentiate patients with from those without ulcers. Methods: One hundred patients younger than 45 years with dyspepsia referred for upper GI endoscopy were included in the study. During endoscopy antral biopsy specimens were obtained for the rapid urease test and histologic examination. At histologic examination gastritis was graded from 0 (normal histologic features) to 3 (severe gastritis). After endoscopy blood was obtained for serologic determination of CagA status. Results: Among the 100 patients 56 were H pylori positive and 44 were H pylori negative. In the group of 56 H pylori –positive patients 36 (64.3%) had peptic ulcers and 20 (35.7%) did not. Among patients with peptic ulcer 34 of 36 (94.4%) were CagA positive and 2 (5.6%) were CagA negative. The respective values for the group of patients without ulcers were 9 of 20 (45%) and 11 of 20 (55%). The difference in the proportion of CagA-positive subjects between the group with and that without peptic ulcer was highly significant ( p < 0.0001). Conclusions: Among young patients with dyspepsia, CagA seropositivity is highly associated with duodenal ulcer at endoscopy. (Gastrointest Endosc 1999;50:511-5.)