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Lactulose hydrogen breath test and functional symptoms in pediatric patients
Ana María Madrid1, Glauben Landskron, Gabriela Klapp
1Laboratory of Motility and Functional Digestive Disorders, GI Section, Medicine Department, University Hospital, University of Chile, Santos Dumont 999, Santiago, Chile. anamariamadrid@gmail.com
Insights
The lactulose hydrogen breath test (LHBT) showed abnormal results in children with functional digestive symptoms, suggesting potential small intestinal bacterial overgrowth (SIBO) or rapid transit. Further investigation is needed to confirm the exact cause.
Area of Science:
- Pediatric Gastroenterology
- Digestive Health
- Microbiome Research
Background:
- The role of small intestinal bacterial overgrowth (SIBO) in pediatric functional digestive disorders is debated due to diagnostic challenges.
- Current diagnostic methods for SIBO in children are difficult to interpret.
Purpose of the Study:
- To analyze the characteristics of the lactulose hydrogen breath test (LHBT) in children experiencing functional gastrointestinal symptoms.
- To evaluate LHBT results based on recent diagnostic criteria in pediatric patients.
Main Methods:
- Seventy-two pediatric patients with functional gastrointestinal symptoms and 17 healthy controls were enrolled.
- Digestive symptoms were assessed via questionnaire; lactose hydrogen breath tests ruled out lactose malabsorption.
- Lactulose hydrogen breath tests (LHBT) measured the time to a 20 ppm H(2) concentration increase over basal levels post-ingestion.
Main Results:
- No significant age or gender differences were observed between patients and controls.
- The mean time to a 20 ppm H(2) increase was significantly shorter in patients (56.3 min) compared to controls (74.7 min).
- In 39% of patients, H(2) rise occurred within 40 min, versus 50-90 min for most controls; symptoms did not correlate with test timing.
Conclusions:
- Abnormal LHBT results were identified in children with functional digestive symptoms.
- The findings suggest potential small intestinal bacterial overgrowth (SIBO) or accelerated intestinal transit.
- Additional diagnostic methods are required to confirm the specific underlying mechanism.
Background:
The role of small intestinal bacterial overgrowth (SIBO) in functional digestive disorders in the pediatric population is a matter of controversy, since methods currently used to establish this diagnosis are difficult to interpret. The aim of this work was to analyze the characteristics of the lactulose H(2) breath test (LHBT) in children with functional gastrointestinal symptoms according to more recent criteria.
Methods:
Seventy-two patients and 17 controls were enrolled. A questionnaire was administered regarding digestive symptoms (abdominal pain, bloating, vomiting, and bowel-movement disorders). A lactose hydrogen breath test was performed to rule out lactose malabsorption and a LHBT was used to measure the time elapsed between lactulose oral ingestion and an increment of H(2) concentration of 20 ppm over basal.
Results:
There were no differences of age and gender between patients and controls. Mean time to 20-ppm change was shorter in patients (56.3 ± 3 min) compared to healthy children (74.7 ± 5 min), p\0.05. In 39% of patients, rise of H(2) occurred during the first 40 min after lactulose ingestion, and in almost all controls, an increment was observed between 50 and 90 min (p\0.05). Symptoms were unrelated to time to 20-ppm change.
Conclusions:
An abnormal LHBT was found in children with functional symptoms of the digestive tract, but the exact mechanism involved, accelerated intestinal transit or SIBO, needs to be confirmed by an additional method.
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