Fig. 1

Chest X-rays of included and excluded patients. a Included patient: A 58-year-old woman with X-ray findings typical of pulmonary edema. b Excluded patient: A 58-year-old woman with marginal X-ray findings showing right-side-dominant infiltration and modest cardiomegaly. Upon admission, this patient had hypotension (systolic blood pressure 70 mmHg), fever (>38°), and elevated levels of acute inflammatory biomarkers (white blood cell count 23,140/μl, serum C-reactive protein 20.0 mg/dl). A systemic inflammatory response due to infection was suspected, and these abnormal parameters and X-ray findings were subsequently resolved with antibiotic therapy. c (excluded patient) An 81-year-old man with marginal X-ray findings showing abnormal pleural and pulmonary shadows (arrows) and pneumothorax (arrowhead). The patient had pleural and pulmonary metastases secondary to renal cancer