Abstract

Background. Lower respiratory tract infections (LRTIs) are considered as problem global public health in the pediatric population. Respiratory virus causes up to 60% of all LRTIs in children. When respiratory virus arrival to the airway, stimulate the production of several pro-inflammatory cytokines in the respiratory epithelium and generate an excessive immune reaction. New evidence has shown that some these cytokines taken in infants undergoing viral LRTIs may be used to predict severe acute illness. Aim. To identify nasopharyngeal biomarkers for prediction of disease severity in LRTI infants. Methodology. Nasopharyngeal swabs from 87 patients <2 years (and 11 healthy) diagnosed as virus positive, were collected to evaluate protein levels expression of IL-3, IL-33, IL-8, TSLP, IL-25 and IL-12p40 using ELISA platform. We followed the progress of the recruited patients during 12 months after entering the study. We recorded data associated to recurrent acute respiratory tract infections (ARIs) episodes, asthma development and corticoids requirement. Results. 45 were diagnosed with LRTI (52%) and 42 were diagnosed as ARIs (48%). We observed that the levels of IL-3, IL-8 and IL-33 increased more in LRTI patients positive for virus. Finally, we found that patients with high IL-33 and IL-8 levels at the beginning of study were more susceptible to cough and ARIs to 1 month and 6 months after first infection, respectively. Conclusions. In this study we observed that high levels of IL-33 and IL-8 are associated with complications in infected patients with virus and they could be potential prognosis biomarker in virus infections.