Lung ultrasound can detect pneumothorax and pulmonary edema, but limited data exist to quantify its accuracy for diagnosing pneumonia. In a prospective study, investigators compared lung ultrasound to chest computed tomography (CT) and chest x-ray among adult patients presenting with unexplained respiratory symptoms to an academic emergency department in Italy.
CT served as the gold standard for diagnosis of an infiltrate consistent with pneumonia. Patients were enrolled when a CT scan was planned. Bedside lung ultrasound was performed within 3 hours of the CT scan by either emergency physicians or internists, and chest x-ray was performed at the discretion of the treating physician.
During the 8-month study period, 285 patients underwent CT and ultrasound, and, of these, 190 also had a chest x-ray. Chest CT was positive for pneumonia in 87 patients. Sensitivity for diagnosing pneumonia was significantly higher with ultrasound than x-ray (81% vs. 64%), while specificities were statistically similar (94% and 90%).