PurposeTo assess gastric pH and its relationship with urease-test positivity and histological findings in children with Helicobacter pylori infection.MethodsFasting gastric juices and endoscopic antral biopsy specimens were collected from 562 children and subjected to the urease test and histopathological examination. The subjects were divided into 3 age groups: 0-4, 5-9, and 10-15 years. The histopathological grade was assessed using the Updated Sydney System, while the gastric juice pH was determined using a pH meter.ResultsThe median gastric juice pH did not differ significantly among the age groups (p=0.655). The proportion of individuals with gastric pH >4.0 was 1.3% in the 0-4 years group, 6.1% in the 5-9 years group, and 8.2% in 10-15 years (p=0.101). The proportions of moderate and severe chronic gastritis, active gastritis, and H. pylori infiltration increased with age (p<0.005). Urease-test positivity was higher in children with hypochlorhydria (77.8%) than in those with normal gastric pH (31.7%) (p<0.001). Chronic and active gastritis were more severe in the former than the latter (p<0.001), but the degree of H. pylori infiltration did not differ (20.9% vs. 38.9%; p=0.186).ConclusionGastric pH while fasting is normal in most children regardless of age. Urease-test positivity may be related to hypochlorhydria in children, and hypochlorhydria is in turn related to H. pylori infection.

Infantile hypertrophic pyloric stenosis (IHPS) is one of the common surgical abdomen in infancy, characterized by progressive non-bilious vomiting. The etiology is unknown, but it likely develops after birth. The pylorus of the stomach becomes thick and triggers progressive vomiting. Abdominal ultrasonography (US) is widely used as a diagnostic tool. Currently, there is a rare IHPS patient with severe metabolic derangement because of general use of abdominal US and its accuracy. We experienced a natural course of a 62-day-old male infant with IHPS who was suffering from intermittent vomiting, loss of weight but had not been properly treated for 1 month. It is needed to make an effort to diagnose differentially in recurrent vomiting infant and check-up regularly, and also educate parents properly.