Respiratory hydrogen excretion as a parameter for lactose malabsorption in children

Area of Science:

• Pediatric Gastroenterology
• Nutritional Science
• Diagnostic Medicine

Background:

• Lactose malabsorption is common in children, affecting nutrient absorption and causing gastrointestinal symptoms.
• Accurate diagnosis is crucial for appropriate dietary management and preventing complications.
• Existing diagnostic methods, like blood glucose tests, have limitations in sensitivity and specificity.

Purpose of the Study:

• To evaluate the accuracy of respiratory hydrogen excretion in diagnosing lactose malabsorption in children.
• To compare the efficacy of respiratory hydrogen testing with blood glucose monitoring.
• To assess children's tolerance to physiological amounts of lactose in skim milk.

Main Methods:

• 52 children (4-15 years) underwent tolerance tests using lactose, glucose plus galactose, and skim milk.
• Respiratory hydrogen excretion was measured post-ingestion.
• Blood glucose levels were monitored during lactose tolerance tests.
• Jejunal biopsies were analyzed for disaccharidase activities in children identified as lactose malabsorbers.

Main Results:

• Ten children (19%) showed increased respiratory hydrogen excretion, indicating lactose malabsorption.
• Respiratory hydrogen excretion was a more accurate indicator of lactose malabsorption than blood glucose increase.
• Two out of ten lactose malabsorbers exhibited intolerance to a physiological amount of lactose in skim milk.
• Lactase deficiency was confirmed in nine of the ten lactose-malabsorbing children via jejunal biopsy.

Conclusions:

• Respiratory hydrogen excretion is a reliable, non-invasive method for diagnosing lactose malabsorption in children.
• This method surpasses blood glucose monitoring in accuracy for lactose malabsorption diagnosis.
• Even small, physiological amounts of lactose in skim milk can reveal intolerance in susceptible children.