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Updated: Apr 6, 2026
Breath Collection from Children for Disease Biomarker Discovery
Published on: February 14, 2019
[Breath tests in children with suspected lactose intolerance]
P Ángela Parra1, C Simone Furió1, A Gabriel Arancibia2
1Estudiantes de Pregrado, Facultad de Medicina, Pontificia Universidad Católica de Chile.
Insights
Lactose intolerance affects many children, with over half showing malabsorption and 27% intolerance in a Chilean study. Symptoms like abdominal pain are common, increasing with age.
Area of Science:
- Pediatric Gastroenterology
- Clinical Epidemiology
Background:
- Lactose intolerance is highly prevalent globally, affecting up to 70% of the population.
- No prior epidemiological studies exist for lactose intolerance in the Chilean pediatric population.
Purpose of the Study:
- To clinically characterize Chilean children undergoing lactose intolerance breath testing.
- Determine frequencies of lactose malabsorption and intolerance.
- Identify common symptoms and assess test performance based on patient origin.
Main Methods:
- A cohort of 194 pediatric patients (ages 1-17) suspected of lactose intolerance was analyzed.
- Lactose intolerance breath tests were conducted, with malabsorption defined by specific hydrogen (H2) and methane (CH4) level increases.
- Intolerance was confirmed when malabsorption was accompanied by a symptom intensity score of ≥7.
Main Results:
- 53% of patients exhibited lactose malabsorption, while 27% were diagnosed with lactose intolerance.
- The prevalence of lactose intolerance ranged from 7.1% to 45.4%, increasing with age.
- Abdominal pain, bloating, and rumbling were the most frequently reported symptoms.
Conclusions:
- The lactose breath test combined with a symptom questionnaire is effective for diagnosing lactose malabsorption and intolerance in children.
- Intolerance frequency increases with age, and testing is more conclusive when requested by a gastroenterologist.
Introduction:
Up to 70% of the world population is lactose intolerance. However, there are no epidemiological studies among Chilean pediatric population affected by this condition.
Objectives:
Clinical characterization of a series of children who underwent the lactose intolerance breath test for lactose intolerance study, establishing intolerance and malabsorption frequencies, the most frequent symptoms, and test performance depending on the origin.
Patients And Methods:
Patients under 18 years old who took the lactose intolerance breath test in the Gastroenterology Laboratory of the Catholic University of Chile, and who were admitted due to clinically suspected lactose intolerance. Malabsorption was considered when there was as an increase of ≥20ppm above the baseline (H2) or ≥34ppm of H2 and methane (CH4) combined. Intolerance was considered when the above was associated with a symptom intensity score ≥7 during registration.
Results:
The analysis included194 patients aged 1 to17 years of age. Of these, 102 (53%) presented with malabsorption, and 53 (27%) were intolerant. The frequency of lactose intolerance varied from 7.1 to 45.4%, and it occurred more frequently at older ages. The most common reported symptoms were abdominal pain, bloating and rumbling.
Discussion:
Lactose malabsorption and intolerance can be investigated from the first years of life using the lactose breath test plus a symptom questionnaire. An increase in the frequency of intolerance with age, and a greater number of positive tests, if they were requested by a gastroenterologist, were observed.
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