Retropharyngeal air and pneumomediastinum: a rare complication of influenza A and asthma in an adult

We report a case of massive pneumomediastinum, small apical pneumothoraces, and retropharyngeal emphysema in an adult female patientwith both influenza A and asthma. Pneumomediastinumoccurs because of a rapid increase of pressure within the alveoli, secondary to forceful coughing or bronchospasm. This pressure increase causes the alveoli to rupture, releasing air into the lung parenchyma andmediastinum. Although pneumomediastinumis usually a benign entity, in some cases, it can progress to subcutaneous emphysema and, as in this case, retropharyngeal emphysema leading to airway compromise. Pneumomediastinum has been previously reported in the pediatric literature in asthmatic patients with influenza; but it has only very rarely been reported as a cause of airway obstruction in adults, and there are no reports in the literature of retropharyngeal emphysema as a result of influenza. This case report highlights the importance of considering chest radiography and computed tomography in asthmatic patients or those with influenza who have suspected extra-alveolar air