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Published on: May 4, 2021

Exhaled nitric oxide is reduced in infants with rhinorrhea

Peter J Franklin1, Stephen W Turner, Graham L Hall

  • 1School of Paediatrics and Child Health, University of Western Australia, Perth, Western Australia, Australia. peterf@ichr.uwa.edu.au

Pediatric Pulmonology
|December 2, 2004
PubMed

Insights

Infants with rhinorrhea, a common cold symptom, show significantly lower exhaled nitric oxide (FE(NO)) levels. These levels normalize after symptoms resolve, indicating FE(NO) is a sensitive marker for respiratory infections in infants.

Area of Science:

  • Pediatric Pulmonology
  • Respiratory Medicine
  • Biomarkers

Background:

  • The impact of common respiratory tract infections (RTIs) on exhaled nitric oxide (FE(NO)) in infants remains unclear.
  • FE(NO) is a non-invasive marker of airway inflammation, but its behavior during infant colds requires further investigation.

Purpose of the Study:

  • To investigate the effect of rhinorrhea, a common symptom of infant colds, on FE(NO) levels.
  • To compare FE(NO) in infants with and without rhinorrhea, and to assess changes after symptom resolution.

Main Methods:

  • FE(NO) was measured in 24 infants with rhinorrhea (with or without cough, excluding wheeze) and compared to 23 healthy infants.
  • A subset of 8 infants with rhinorrhea was re-tested after symptom resolution.
  • Infants with a history of recurrent wheeze were included in the study groups.

Main Results:

  • Infants with rhinorrhea exhibited significantly lower FE(NO) levels (11.9 ppb) compared to healthy infants (23.8 ppb).
  • In infants with rhinorrhea, FE(NO) levels increased significantly from 7.5 ppb during illness to 34.1 ppb after symptom resolution.
  • Reduced FE(NO) was observed in infants with rhinorrhea regardless of their history of recurrent wheeze.

Conclusions:

  • Infants experiencing rhinorrhea associated with common colds have reduced FE(NO) levels.
  • FE(NO) levels increase and normalize following the resolution of cold symptoms in infants.
  • FE(NO) serves as a potential indicator of respiratory infection in infants, irrespective of underlying respiratory conditions like recurrent wheeze.

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