We retrospectively studied the clinical and histologic features of pediatric fundic gland polyps (FGPs) in 16 patients. FGPs had an endoscopic prevalence of 0.25% in 8527 pediatric gastric biopsies. Five patients had familial adenomatous polyposis (FAP). The median age of onset was 17.7 years in FAP and 17.3 years in sporadic patients. All syndromic patients were asymptomatic and FGPs were identified during surveillance for existing or concurrent colon polyps. They did not take antacids. In comparison, all 11 sporadic FGPs were identified during evaluation of symptomatic patients who had taken antacids (median duration 21 months). Syndromic FGPs can be multiple at single endoscopy and were more likely to recur, while sporadic FGPs were often single. None of the sporadic patients had recurrence of FGPs or a subsequent diagnosis of FAP during a median follow-up of 20.5 months. The dilated fundic glands were lined by parietal and chief cells only in a majority (22/41, 53.7%) of syndromic FGPs, while additional tall mucinous lining cells were found in all sporadic FGPs. Syndromic FGPs did not have parietal cell hypertrophy in the background oxyntic mucosa. Nuclear immunopositivity for beta-catenin was essentially absent in all the FGPs. In conclusion, FGPs were rare in pediatric patients. In syndromic patients, FGPs are asymptomatic and did not precede colon polyps. Prolonged antacid intake seems to be associated with development of sporadic FGPs. Cellular components of dilated fundic glands and background parietal cell hypertrophy can be useful features to eliminate concern for syndromic polyposis.
Keywords: familial adenomatous polyposis; fundic gland polyps; histopathology; nuclear beta-catenin; pediatric.