Validation of Clara Cell Protein as a Novel Diagnostic Biomarker for the Differentiation of Cardiogenic Pulmonary Edema From Non-Cardiogenic Pulmonary Edema

Inclusion Criteria: * Adult patients aged 18 years or older. * Both sexes. * Patients requiring intensive care unit (ICU) admission and intubation. * Inclusion criteria followed the American-European Consensus Conference diagnostic guidelines for acute lung injury (ALI) and acute respiratory distress syndrome (ARDS): acute respiratory failure onset, bilateral infiltrates on chest radiography, a PaO2/FiO2 ratio below 300 for ALI or 200 for ARDS and no evidence of left atrial hypertension Exclusion Criteria: * Critically ill but not intubated. * Had a mixed cause of pulmonary edema like pneumonia with heart failure.