Interferon Alpha As Marker Of Disease Severity In Children With Influenza: A Cohort Study

MATTIELLO, R; STEIN, RT; PINTO, L.A.; PITREZ, PM; JONES, MH; SCOTTA, M; ACOSTA, PL; PORTO, BN; POLACK, FP

Congreso; American Thoracic Society 2017 International Conference; 2017

Background/Aim: According to experimental data, interferon type I has a key role in innate immune response against influenza infection.Studies on humans are still scarce and the characterization of interferon response in children may help to identify patients at risk. Thisstudy aims to assess the relationship between respiratory levels of interferon I (α and β) and severity of influenza infection in children.Methods: A multicenter prospective cohort study enrolled children aged less than five years of age with influenza-like illness at emergencyroom and pediatric ward in one center in Porto Alegre, Brazil, and in twelve centers in Buenos Aires, Argentina. Clinical and demographicdata and respiratory secretions through nasal wash were obtained. Influenza infection was confirmed with Reverse-TranscriptionPolymerase Chain Reaction. Respiratory levels of interferon-α and β were measured by ELISA and were compared between patientshospitalized and outpatients.Results: One hundred and eighteen patients with confirmed influenza infection were included, 100 of these requiring hospitalization.Children admitted to hospital were significantly younger (6.5 vs 15 months), with lower rates of updated vaccination (11.6% vs 38.9%),lower monthly family income (365.85 vs 507.93 US dollars) and higher number of smokers at home (61.2% vs 27.8%). All other clinical anddemographical data were similar between groups. Median levels of interferon-α (pg/ml) were significantly higher in outpatients comparedto those admitted with median of 267.25 (IQ 65.7-648.6) vs 0.0 (IQ 0.0-0.15), p