Les séquelles de virose en pneumopédiatrie

Community-acquired viral bronchopneumonia is frequent, particularly in children, and can be associated with all types of respiratory viruses. Immature immunity explains the vulnerability to respiratory pathogens during childhood. Epithelial cells distributed throughout the airway epithelium are the target of viruses. Epidemiological studies report a decrease in respiratory function in adults, regardless of confounding factors, who had pneumonia before the age of 2 or even 7 years. This reduction in respiratory function is a consequence of the initial involvement and of the accelerated physiological decline in adulthood. Studies on the origin of bronchial dilatation have found a history of infectious pneumonia in more than 50% of cases. Adenoviral infections in particular are involved. Postinfectious obstructive bronchiolitis can occur even in immunocompetent children. The initial clinical picture is often flu-like, and is subsequently marked by a dissociation between important functional signs and a poor clinical presentation. The long-term course is not predictable but can lead to lethal chronic respiratory failure. Diffuse infiltrative pneumonitis is characterized by pulmonary diffuse infiltration with inflammatory cells and fibrosis. The role of viruses in its development has been mentioned due to the presence of cellular inclusions evoking viral particles in the lungs of affected children. Finally, most epidemiological studies emphasize the association between wheezing symptoms secondary to viral infection in childhood and the subsequent risk of developing asthma.