Background: Triple therapy with a proton-pump inhibitor and two antibiotics is widely used in the treatment of Helicobacter pylori infection in adults. Experience with such therapy in the pediatric population is limited. This was a prospective, nonrandomized, open-label trial to evaluate safety and efficacy of a combination of lansoprazole, clarithromycin, and amoxicillin in symptomatic children with H. pylori infection. Methods: Children with H. pylori gastritis diagnosed by endoscopy performed for persistent nausea, vomiting, recurrent abdominal pain, and diarrhea with consistent histology were treated with the regimen of 0.45 mg/kg per day lansoprazole divided into two doses (maximum dose, 15 mg twice daily), amoxicillin 30 mg/kg per day in two doses (maximum dose, 1.0 g twice daily), and 250 mg clarithromycin twice daily (<10 years old) or 500 mg twice daily (>10 years old) for 2 weeks. Pre- and posttreatment endoscopic biopsy specimens were graded for the severity of gastritis and H. pylori density by a blinded pathologist. A questionnaire for assessing the severity of symptoms at the time of initial and second endoscopy were completed by patient and/or parent. Results: Thirty-two children (age range, 1-25 years; mean age, 11 years; 19 females, 13 males) were treated with this regimen during an 18-month period. H. pylori organisms with varying grades of gastritis were present in tissue specimens of all patients. Only 28 children had follow-up endoscopy, which showed eradication of H. pylori in 15 (54%) children. Histologic symptoms of gastritis improved after therapy in the whole group. Overall, symptoms of vomiting, abdominal pain, diarrhea, anorexia, and halitosis significantly improved (P < 0.05). Minor adverse effects of therapy occurred in 25% of patients. Conclusions: Symptoms, histologic, and endoscopic findings improved after triple therapy in children with H. Pylori gastritis; however, eradication of bacteria was achieved in only 56% of children. (C) 2000 Lippincott Williams & Wilkins,lnc.