IL1RA polymorphism and levels associated with adverse outcome in severe community acquired pneumonia in children: A hospital-based study in India

Abstract

Background: High morbidity and mortality due to community acquired pneumonia (CAP) is seen in children under 5-years of age in India. Besides identified risk factors for CAP there may be phenotype–genotype association with cytokines, resulting in enhanced inflammatory response resulting in adverse outcome (AO) i.e. complications or death. Aim: To assess the association of IL-1RA gene polymorphism on serum levels of IL-1RA and with AO in children aged hospitalized for severe CAP. Method: Prospective study conducted in a tertiary care teaching hospital after obtaining ethical approval. Included were children between 2 to 59 months of age hospitalized with WHO defined severe pneumonia with radiological abnormalities. Excluded were children with suspected cystic fibrosis, tuberculosis, malignancy, immunodeficiency and congenital heart disease. PCR used to analyze the Variable Number of Tandem Repeats of IL-1RA polymorphism and ELISA test to detect to serum IL-1RA levels. Results: In 2014-16, 420 cases were screened and 350 included, of which 132 were without and rest with complications (empyema /effusion, pyo-pneumothorax, acute respiratory distress syndrome, septic shock) and 24 expired. Higher risk of AO seen in A1/A2 (OR=3.55, p Conclusion: In IL-1RA gene, A1 allele is protective and A2 increases the risk of complication as well as serum IL-1RA level indicating possibly enhanced inflammatory response in pediatric CAP.