An Acute Pulmonary Embolism Patient with Negative D-dimer Masquerading as Right Pneumonia with Pleural Effusion Proven by CT Pulmonary Arteriography: a Case Report and Literature Review

BACKGROUND: We report an acute pulmonary embolism with negative D-dimer masquerading as right pneumonia with pleural effusion proven by CT pulmonary arteriography (CTPA). METHODS: Appropriate laboratory tests are carried out. The application of vascular ultrasound for the cause of left lower extremity edema. CTPA were performed when vascular ultrasound suggested the existence of venous thrombosis of left lower extremity. RESULTS: Serum D-dimer was negative. Vascular ultrasound revealed left lower extremity venous thrombosis, CTPA demonstrated large emboli in the main pulmonary artery and main pulmonary artery branches. CONCLUSIONS: Negative serum D-dimer is not safe to rule out acute pulmonary embolism. When CT shows peripheral triangle-shaped infiltrate with pleuritis or small pleural exudate, physicians should pay attention to pulmonary infarction.