Influenza and antiviral treatment: Case

This school-age child with asthma presents the classic severe-influenza trajectory: an abrupt febrile illness in a high-risk host, early viral pneumonia complicated by an asthma exacerbation, and then the feared biphasic deterioration of secondary bacterial pneumonia. The candidate must demonstrate risk-stratified antiviral use, escalation of respiratory support, empirical antibiotic selection for post-influenza bacterial pneumonia, and a prevention plan for the child and the household. ^[2]

Clinical findings

The key findings at presentation are the abrupt onset in a child with a high-risk condition, the hypoxia and intercostal recession of viral pneumonia, and the wheeze of an influenza-triggered asthma exacerbation. The candidate should identify that chronic lung disease places this child in a different risk stratum, in which the same virus is far more likely to cause pneumonia, respiratory failure and a complicated course. ^[2]

The examination should assess work of breathing, oxygenation, recession, air entry and wheeze, and should look for the complications that change management — dehydration, altered consciousness suggesting encephalopathy, tachycardia out of proportion to fever or poor perfusion suggesting myocarditis, and a new fever after improvement suggesting secondary bacterial pneumonia. The differential at presentation includes an influenza-triggered asthma exacerbation, primary viral pneumonia, other viral respiratory infections, and Mycoplasma pneumonia, but the abrupt onset with the classroom cluster and the hypoxia make influenza with viral pneumonia the leading diagnosis. ^[2]