[H. pylori infection at the duodenal bulb in different endoscopic diagnoses]

Biopsy samples obtained by endoscopy to diagnose infection by H. pylori usually come from the antral region. Nevertheless, there are few reports documenting the prevalence of infection at duodenal level. OBJECTIVE. To investigate the prevalence of H. pylori infection in duodenal bulb in different endoscopic diagnosis. METHODS. 331 patients with the following endoscopic diagnosis were studied: normal appearance (n = 55), gastritis (87), gastric ulcer (49), duodenal ulcer (120), and duodenitis (20). At endoscopy, different samples from duodenal bulb were obtained (apart from gastric fundus, body and antrum), which were processed for microbiology (Gram stain and culture) and histology (hematoxilin-eosin). RESULTS. Patients with duodenal ulcer or duodenitis had the highest H. pylori infection rate at duodenal bulb (47.7% and 65%, respectively). Differences were significant when compared with normal appearance (14.5%; p < 0.001) and gastritis (25%; p < 0.05). In all patients with H. pylori at duodenal bulb this organism was also detected at antral region. CONCLUSIONS. 1) The highest prevalence rates for H. pylori infection in duodenal bulb were found in patients with duodenal ulcer or duodenitis. 2) Diagnosis of H. pylori infection should not be based on the duodenal bulb samples alone, as this sample yields high false-negative results.