Respiratory Tract Infections Respiratory tract infections caused by S. aureus occur in selected clinical settings. S. aureus is a cause of serious infections in newborns and infants; these infections present as shortness of breath, fever, and respiratory failure. Chest x-ray may reveal pneumatoceles (shaggy, thin-walled cavities). Pneumothorax and empyema are recognized complications of this infection. In adults, nosocomial S. aureus pulmonary infections are commonly seen in intubated patients in intensive care units. The clinical presentation is no different from that encountered in pulmonary infections of other bacterial etiologies. Patients produce increased volumes of purulent sputum and develop respiratory distress, fever, and.