Background: Children with type 1 diabetes mellitus (T1DM) are at risk of many infections, including Helicobacter pylori (H. pylori).
Objectives: To evaluate the frequency of H. pylori infection and its effect on glycemic control and insulin needs in children with T1DM.
Patients and methods: A case-control study including 40 children with T1DM and 40 non-diabetic control children. Clinical and demographic data and the presence of gastrointestinal symptoms were assessed in both groups. Data about the duration of diabetes, insulin doses, and glycemic control were collected in children with T1DM. The H. pylori antigen in stool, complete blood count, and glycated hemoglobin (HbA1c) levels were assessed in all the study participants.
Results: In children, T1DM was associated with a higher prevalence of H. pylori in stool samples compared to those without diabetes (32.5% vs. 10%, p = 0.01). Among children with T1DM, those with H. pylori in their stool had more gastrointestinal symptoms than those without (p < 0.001).  However, H. pylori status did not affect daily insulin dose, basal insulin dose, or HbA1c levels in children with T1DM (p = 0.97, 0.49, and 0.38, respectively).
Conclusion: Although H. pylori infection was more frequent among children with T1DM, it had no significant impact on the insulin requirement or the glycemic control. However, the frequencies of gastrointestinal symptoms were increased among T1DM children with positive H. pylori stool antigen.