Clinical signs of pneumonia: cough, dyspnea, or rales, PLUS
Abnormal physiology: increased arterial-alveolar oxygen gradient, or the need for supplemental oxygen support
Absence of lower respiratory tract infection
Negative BAL for bacterial and nonbacterial organisms, OR
Negative surgical lung biopsy
Widespread alveolar injury
Multilobar infiltrates on CXR or CT, PLUS
Clinical signs of pneumonia: cough, dyspnea, or rales, PLUS
Abnormal physiology: increased arterial-alveolar oxygen gradient, or the need for supplemental oxygen support
Absence of lower respiratory tract infection
Negative BAL for bacterial and nonbacterial organisms, OR
Negative surgical lung biopsy
The definition of diffuse alveolar hemorrhage (DAH) requires the data in the table, plus progressively bloodier aliquots of lavage fluid noted during bronchoscopy.