Background Endoscopic balloon dilation has been used to treat patients with ga stric outlet obstruction caused by peptic stricture.This study assessed the role of endoscopic balloon dilation in patients with gastric outlet obstruction with or without Helicobacter pylori infection. Methods Consecutive patients seen bet ween January 1996 and September 2001 with benign gastric outlet obstruction (def ined as stenosis preventing the passage of a 9-mm diameter endoscope, vomiting, succussion splash, and recent weight loss) were prospectively studied. Exclusio n criteria were the following: refusal to undergo dilation, and gastric outlet o bstruction because of malignancy. At endoscopy, antral biopsy specimens were obt ained for histopathologic evaluation and for a rapid urease test for Helicobacte r pylori infection.Patients then underwent dilation with through-the-scope bal loons.After balloon dilation, patients with Helicobacter pylori infection were t reated to eradicate the infection. Results Fifty one patients (33 men, 18 women; median age 65 years; IQR 44-79 years) were studied; 33 consented to endoscopic balloon dilation. Symptom resolution occurred in 25 patients (14 Helicobacter p ylori positive, 11 Helicobacter pylori negative).During amedian follow-up of 24 months (IQR 16-40 months), 3 of 14 patients in the Helicobacter pylori positiv e group and 6 of 11 in the Helicobacter pylori negative group developed further ulcer complications (p=0.039). Conclusions After endoscopic dilation for gastric outlet obstruction, eradication of Helicobacter pylori infection is associated with fewer ulcer complications. Background Endoscopic balloon dilation has been used to treat patients with ga stric outlet obstruction caused by peptic stricture. This study evalu the role of endoscopic balloon dilation in patients with gastric outlet obstruction with or without Helicobacter pylori infection. Methods Consecutive patients seen bet ween January 1996 and September 2001 with benign gastric outlet obstruction (defined as stenosis preventing the passage of a 9-mm diameter endoscope, vomiting, succussion splash, and recent weight loss) were prospectively studied. Exclusio n criteria were the following: refusal to undergo dilation, and gastric outlet o bstruction because of malignancy. At endoscopy, antral biopsy specimens were obtined for histopathologic evaluation and for a rapid urease test for Helicobacter r pylori infection. Patients then underwent dilation with through-the-scope bal loons. After balloon dilation, patients with Helicobacter pylori infection were t reated to eradicate the infection. R Symptoms Fifty one patients (33 men, 18 women; median age 65 years; IQR 44-79 years) were studied; 33 consented to endoscopic balloon dilation. Symptom resolution occurred in 25 patients (14 Helicobacter pylori positive, 11 Helicobacter pylori negative) . After amedian follow-up of 24 months (IQR 16-40 months), 3 of 14 patients in the Helicobacter pylori positiv e group and 6 of 11 in the Helicobacter pylori negative group developed further ulcer complications (p = 0.039). Conclusions After endoscopic dilation for gastric outlet obstruction, eradication of Helicobacter pylori infection is associated with fewer ulcer complications.