A comparison of IL-2 levels in nasopharyngeal and endotracheal aspirates of babies with respiratory syncytial viral bronchiolitis.
BACKGROUND
Cytokines such as IL-2 are thought to be important in the pathogenesis of respiratory tract inflammation. Cytokine levels in nasopharyngeal aspirates (NPAs) have been used as a measure of respiratory inflammation in children with viral infections, but it is unclear whether they reflect levels in the lower respiratory tract.


OBJECTIVE
We sought to assess the correlation between IL-2 levels in the nasopharyngeal and endotracheal secretions of children intubated with respiratory syncytial virus (RSV)-positive bronchiolitis.


METHODS
NPA and endotracheal aspirates were collected concurrently from intubated infants with RSV-positive bronchiolitis. IL-2 levels were assayed by ELISA, and the results were compared according to collection site.


RESULTS
Nine paired specimens were collected. IL-2 levels ranged from 31 pg/mL to 8040 pg/mL. No significant difference was found in the geometric mean IL-2 values from the 2 collection sites. The intraclass correlation coefficient between NPA IL-2 levels and endotracheal aspirate IL-2 levels was 0.83.


CONCLUSIONS
IL-2 levels in NPAs are comparable with those in the lower respiratory tracts of infants with RSV-positive bronchiolitis. NPA cytokine levels provide a simple and useful means of assessing respiratory tract inflammation.
Joshi
P
P
Department of Immunology and Infectious Diseases, The Royal Alexandra Hospital for Children, Westmead, Paramatta, NSW, Australia.
Kakakios
A
A
Jayasekera
J
J
Isaacs
D
D
D001990:Bronchiolitis, Viral / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007376:Interleukin-2 / Q000378:metabolism*; D008297:Male; D017817:Nasal Lavage Fluid / Q000737:chemistry*; D009305:Nasopharynx / Q000378:metabolism*; D018357:Respiratory Syncytial Virus Infections / Q000378:metabolism*; D014132:Trachea / Q000378:metabolism*
D007376:Interleukin-2