In children, Helicobacter pylori is thought to play an important role in the pathogenesis of chronic gastritis and peptic ulcer disease, especially duodenal ulcer. H. pylori has also been discussed as a possible risk factor of common pediatric diseases such as iron deﬁciency anemia or atopic dermatitis.
Biopsy tests including histology, urease test, and culture have been widely used: they are generally reliable diagnostic tests for H. pylori infection. However, these tests are invasive and may show false negative results in some patients because colonization of the organism is occasionally patchy in the stomach.
On the other hand, among noninvasive tests, serology has been found to be less reliable in children than in adults, and the stool antigen test is still being studied for its clinical usefulness in children. Another noninvasive test, the 13C-urea breath test (UBT), has been developed, and early adult studies have demonstrated a high sensitivity and speciﬁcity for diagnosing active H. pylori infection. Because this test uses urease activity of H. pylori in the whole stomach, the problem of patchy colonization might be overcome.
Moreover, because 13C is a stable and nonradioactive isotope, the 13C-UBT would be a suitable method in children. There have been several studies on the 13C-UBT in children suggesting diagnostic accuracy for the infection.