A 42-year-old woman was intubated in the ICU because of respiratory distress after being admitted for treatment of abdominal sepsis. Shortly after starting antibiotics, she acutely developed respiratory distress. A chest x-ray before intubation revealed equally bilateral lower lobe infiltrates, which were further defined with a CT scan of her chest. The CT scan demonstrated bilateral consolidation confined to the posterior lung regions. Which of the following diagnostic criteria support the clinical diagnosis of ARDS in this patient?
A. PaO2/FiO2 > 200 mm Hg
B. Pulmonary artery occlusion pressure ≤ 18 mm Hg
C. 10% neutrophil concentration of lung lavage fluid
D. Absence of predisposing condition
E. Gradual onset