Study population
Infants aged between 2 and 18 months diagnosed with noisy breathing,
either clear wheezing or clear rattling, were recruited at a paediatric
clinical practice in Hasselt, Belgium after parents provided informed
consent. Exclusion criteria were preterm birth (gestational age
< 37 weeks), congenital or genetic disorders, chronic
respiratory diseases. All participants were treated according to
standard clinical practice given that treatment did not depend on the
study and vice versa. Two follow-up visits were planned three and six
weeks after the first consult. At all three visits the paediatrician
scored the intensity and duration of rattling and/or wheezing heard
during auscultation. Based on the paediatrician’s rattle and wheeze
scores, patients were classified into mild, moderate or severe rattling
or recovered. Additionally, exhaled breath was collected at every visit.
The study has been approved by the ethical review committee of the Jessa
Hospital in Hasselt and with the advice of the medical ethics committee
of the University of Hasselt (nr. B243201837634).