Longitudinal Preschool Wheeze Biomarker Study

Official title

Development of Non-invasive Biomarkers to Direct Individualised Management of Preschool Wheeze

Overview

Preschool children (aged 1-5 years) account for 75% of all UK childhood wheezing hospitalisations. This has not changed over 20 years, meaning current treatments are not working and a new approach is needed. Currently, all preschool wheezers are treated with inhaled steroids. However, only about 25% of patients, with allergies, respond well to inhaled steroids; for the other 75%, they are ineffective. This research group has found that some preschool wheezers may have other causes but there are no specific, non-invasive tests to match the right treatment to each child. The goal of this observational study is to test various bedside tests for this purpose in preschool children with wheeze, to see if they are feasible, accurate and acceptable in this age group. The research team would like to investigate the following aims: Aim 1 - To test the proposed panel of simple bedside tests below, to see how accurately they corelate with lower airway infection or inflammation. Aim 2 - To test the acceptability of these bedside tests are to parents and children, and if they reflect the child's symptoms, symptoms control and medication use. Aim 3- A small proof-of -concept study, to test if these simple bedside tests, can be used to determine treatment for each individual child. The panel of simple non-invasive tests that the research team are proposing are: 1. Skin prick tests to common allergies (house dust mite, cat, dog, grass, tree pollen, mixed moulds) 2. Finger prick blood test 3. Phlegm test for bacteria 4. Nose and throat swab for bacteria 5. Lung function test called forced oscillation technique (FOT)

Detailed description

Research Question:

Can the research team identify simple bedside tests that can give quick, accurate results while being acceptable to parents and children, and can these tests be successfully used in clinical practice, to decide treatment for preschool wheeze?

Participants will be asked to do these simple tests- skin prick test, finger prick blood test, breathing test, throat swab, and a test to catch their phlegm. The researchers will use two tests to identify children who are likely to respond to inhaled steroids: skin tests for allergies and a finger prick blood test. To identify children with bacterial infections in their lungs, where antibiotics will be useful, the team will obtain a sample of sputum (phlegm) after a salty mist inhalation (saline nebuliser), and will test the accuracy of a throat swab that detects bacteria. The research team will also test how cells called neutrophils work in children without allergies or infection with the same finger prick blood test above. A breathing test called forced oscillation will be used to identify children who may respond to their reliever "blue" inhaler during wheezing attacks.

The research team will also recruit a small number of children, for a trial in which their treatment will be guided by their test result, to see if parents are willing to take part in such a study, before designing a larger trial. This study will be the first to show that new tests can identify different types of preschool wheezing and can be used to plan treatment based on individual children's needs. Researchers will compare to see if children who have their treatment based on the simple bedside tests do better than the children who are just given inhaled steroids.

Interventions

• Procedure Bronchoscopy, with bronchoalveolar lavage and endobronchial biopsy
  These children who will be having a bronchoscopy (a long thin tube, with a camera at the end, which is put inside the lung to look at and collect samples) as part of their standard clinical management, determined by their own consultants or treating physicians. They will be having lung samples (washings from the lung and a tiny piece of tissue taken from the breathing tubes) taken as part of their usual medical management. The research team will ask for consent to use the leftover samples for th
• Diagnostic test Skin prick test
  To identify children with allergies. This test will not be done if the child has had allergy testing in the last 6 months
• Diagnostic test Finger prick blood test
  Finger prick testing will be used for blood samples, and it is the same technique used by children with diabetes, to test their blood sugar levels, and therefore is regularly used in this age group successfully. The research team will be obtain the results within minutes, using a point-of-care device. A few more drops of blood, from the same finger prick sample, will be taken to look at how one of the blood cells work, in more detail, in the laboratory. There is no additional finger prick requir
• Diagnostic test Forced oscillation technique (FOT)
  Breathing test will be performed using forced oscillation technique (FOT), to see how the child's lungs work and to detect airway inflammation. The test will be explained to the child and completed using our established protocols. This test will only require the child to breathe in and out normally, and therefore can be done in preschool aged children. The current test that is used to check lung function called spirometry cannot be used in preschool children, as it involves following complicated
• Procedure Sputum induction
  Sputum induction is a test of obtaining phlegm after inhalation of salt water mist (saline nebuliser) and this will allow the research team to look for any relationships between infection in the lungs and the accuracy of the less invasive, nose and throat swabs. The research team will obtain phlegm samples, with a quick suction after patients have inhaled the salty mist (saline nebuliser) which will help loosen up their phlegm. If the child can cough it up, they will be encouraged to do it.
• Diagnostic test Oropharyngeal swab
  Swabs from children's nose and throats (similar to swab tests that are done for Covid tests), that will be used to test for bacterial infection

Primary outcome measures

• Longitudinal study of skin prick tests as biomarkers of preschool wheeze [Time frame: 3 years]
• Longitudinal study of finger-prick point of care test for eosinophil count as a biomarker of preschool wheeze [Time frame: 3 years]
• Longitudinal study of blood neutrophil phenotype as a biomarker of airway infection [Time frame: 3 years]
• Longitudinal study of blood neutrophil chemotaxis as a biomarker of wheezing phenotype [Time frame: 3 years]
• Longitudinal study of oropharyngeal swab and induced sputum PCR as a biomarker of airway infection [Time frame: 3 years]
• Longitudinal study of lung function test (FOT) as a biomarker of airway reversibility [Time frame: 3 years]

Secondary outcome measures (6)

• Association between eosinophil counts and patient symptom control [Time frame: 3 years]
• Patient acceptability of finger prick blood eosinophil count as a non-invasive biomarker in preschool wheeze [Time frame: 3 years]
• Patient acceptability of skin prick test as a non-invasive biomarker in preschool wheeze [Time frame: 3 years]
• Patient acceptability of forced oscillation technique as a non-invasive biomarker to determine lung function and airway reversibility in preschool wheeze [Time frame: 3 years]
• Patient acceptability of oropharyngeal swab and induced sputum PCR as a biomarker of airway infection in preschool wheeze [Time frame: 3 years]
• Correlation between eosinophil counts and symptom burden of preschool wheeze to caregivers [Time frame: 3 years]

Eligibility criteria

Inclusion criteria

Aim 1, 2 and 3:

• Children aged 1-5 years
• More than 2 hospitalisations for acute wheeze in the last year or
• At least 1 admission requiring high dependency unit or intravenous bronchodilator therapy in the last year.

Aim 1 only:

\- children undergoing clinically indicated bronchoscopy, as determined by their existing medical team, as part of their standard management

Exclusion criteria

• Alternative respiratory diagnosis such as cystic fibrosis or bronchiectasis.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Observational model

Cohort

Study locations

United Kingdom · 1 center

• Royal Brompton Hospital — London

Publications

• Robinson PFM, Fontanella S, Ananth S, Martin Alonso A, Cook J, Kaya-de Vries D, Polo Silveira L, Gregory L, Lloyd C, Fleming L, Bush A, Custovic A, Saglani S. Recurrent Severe Preschool Wheeze: From Prespecified Diagnostic Labels to Underlying Endotypes. Am J Respir Crit Care Med. 2021 Sep 1;204(5):523-535. doi: 10.1164/rccm.202009-3696OC. PMID 33961755

Identifiers

NCT: NCT06237660 · 23IC8468 · GN3005

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗