Abstract
PURPOSE OF REVIEW: Asthma is among the most common conditions managed by pediatricians. This review summarizes recent advances in our immunologic understanding of asthma, focusing on cell types implicated in pathogenesis outside of the Th2 paradigm. Early-life respiratory viral infections are a key risk factor for the development of pediatric asthma. Literature detailing the epidemiologic and immunologic connection between early-life viral infections and asthma is also reviewed. RECENT FINDINGS: Asthma is an umbrella term used clinically, but the underlying immune mechanisms can be highly variable. These differing endotypes of asthma can be driven by distinct granulocyte, CD4 + T-cell, and innate-cell subsets, all with therapeutic implications. Early-life viral infection is a well described risk factor for asthma development. Understanding the differences in the immune system early in life, focused on the lung milieu, has shed light on the mechanisms connecting these two conditions. SUMMARY: Early-life respiratory viral infections and asthma have high prevalence in pediatrics, with the former raising the risk for the latter. Understanding the immunologic mechanisms is critical in understanding this connection. Further, our understanding of the drivers of asthma in pediatrics has expanded beyond the canonical pathways.