Unmasking of left upper lobe bronchial atresia in a case of H1N1 pneumonia.

We describe a case of H1N1 pneumonia with left upper lobe bronchial atresia. Although bronchial atresia as an isolated occurrence is an innocuous finding, but when it is superimposed by another major insult, it can amplify the disease effect and can have adverse implications leading to significant morbidity. This report highlights the fact that anatomical anomalies can be the cause of inordinately severe or prolonged course of acute respiratory infection in children.