Metabolites in Blood and Breath in Metabolic Conditions

NCT07704606 | Not Yet Recruiting

• 1 other identifier: 2026-00730
• Study Type: observational
• Target: 100
• Locations: 0 countries
• Sites: N/A

Brief Summary

In patients with inborn errors of metabolism (IEM) and in those requiring a ketogenic diet for the treatment of medical conditions, relevant biochemical analytes are routinely and regularly measured in venous or capillary blood samples. Repeated venipuncture for blood collection is invasive, burdensome, and resource-intensive. As an alternative, capillary blood sampling can provide some relief for the measurement of a limited number of metabolites. Nevertheless, the frequent finger pricks required to obtain capillary blood samples can still be uncomfortable for patients. Therefore, patients could benefit if non-invasive breath measurements were to replace the currently invasive biochemical monitoring methods in the future. In this study, the usability of metabolite measurements across matrices (venous blood, capillary blood, breath captured by a handheld sensor and breath in a collection bag) in IEM patients, individuals prescribed special health-related diets, and healthy volunteers will be investigated. The usability of a handheld breath sensor for remote monitoring of patients will also be tested. Lastly, exploratory investigations will be performed to identify new disease biomarkers in breath.

Conditions

Inborn Errors of Metabolism; Epilepsy (Treatment Refractory)

Outcome Measures

Primary Outcomes (1)

• Concentration (μmol/L) of metabolites of clinical interest in venous blood, capillary blood and breath of participants.

  1. Concentration of beta-hydroxybutyrate in venous and capillary blood 2. Concentration of acetone in exhaled breath 3. Concentration of ammonia in venous blood and exhaled breath 4. Concentration of amino acids (alanine, arginine, asparagine, aspartic acid, citrulline, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, ornithine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine and valine) in venous blood, capillary blood and exhaled breath.

  2 hours to 2 weeks

Secondary Outcomes (4)

• Correlation of metabolite concentrations in different matrices

  2 hours to 2 weeks

• Participant self-report questionnaire on a 4-point Likert scale on the burden of each sampling method

  2 hours to 2 weeks

• Participant self-report questionnaire on a 4-point Likert scale on the usability of the handheld breath sensor for remote measurements of metabolites

  2 hours to 2 weeks

• Untargeted SESI-based mass spectrometry analysis of exhaled breath captured in a bag

  2 hours

Study Arms (1)

Patients or healthy adult volunteers

Other: Observational Study

Interventions

Observational Study OTHER

no intervention

Patients or healthy adult volunteers

Eligibility Criteria

• Age: 4 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients who are routinely cared for at the study site will be invited to participate. Healthy volunteers will be recruited through communication with healthy family members accompanying patients to hospital visits and the general population through flyers.

You may qualify if:

• Patients aged 4-20 years old with refractory epilepsy on a ketogenic diet, or
• Patients aged 4 years old and above with a confirmed diagnosis of urea cycle disorders, organic acidurias, amino acidopathies and fatty acid oxidation defects, or
• healthy adults and
• informed consent

You may not qualify if:

• Physical findings at screening that would compromise safety of the participant or quality of study data. Examples include presentation of fever, pulmonary complications, presence of disease comorbidities that might interfere with study result and inability to comply with study procedures.

Sponsors & Collaborators

• University Children's Hospital, Zurich: lead
• ETH Zurich (Switzerland): collaborator

MeSH Terms

Conditions

Metabolism, Inborn Errors; Epilepsy

Interventions

Observation

Condition Hierarchy (Ancestors)

Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Metabolic Diseases; Nutritional and Metabolic Diseases; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases

Intervention Hierarchy (Ancestors)

Methods; Investigative Techniques

Central Study Contacts

Johannes Häberle

CONTACT

+41 44 249 59 88; Johannes.Haeberle@kispi.uzh.ch

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Prof. Dr. med

Study Record Dates

• First Submitted: July 2, 2026
• First Posted: July 15, 2026
• Study Start (Estimated): October 1, 2026
• Primary Completion (Estimated): October 1, 2036
• Study Completion (Estimated): October 1, 2037
• Last Updated: July 15, 2026

Record last verified: 2026-07