Clinical features and misdiagnosis of connective tissue disease plus pulmonary embolism

Objective To evaluate the clinical features and reasons of misdiagnosis of connective tissue disease plus pulmonary embolism (PE). Methods The clinical data were reviewed retrospectively for 22 hospitalized patients with connective tissue disease and PE from February 2006 to March 2014. And the features of onset, clinical and laboratory characteristics, imaging tests and causes of misdiagnosis were analyzed. Results There were 12 males and 10 females with an average age of (36.2±14.2) years. And 12 (54.5%) PE patients had concurrent deep venous thrombosis. Antiphospholipid syndrome and Behcet's disease were the major causes of connective tissue disease. Chest distress, palpitation and extremity swelling were initial symptoms. There were elevated erythrocyte sedimentation rate (n=11, 50.0%), elevated C-reactive protein (n=8, 36.4%) and abnormal autoantibody (n=15, 68.2%) respectively. Computed tomography showed pulmonary arteries stenosis, occlusion and aneurismal dilation. Eighteen (81.8%) patients had pulmonary hypertension with a systolic pulmonary pressure of (72±20) mmHg (1 mmHg=0.133 kPa). And 3 of them presented severity of pulmonary pressure non-matched to the degree of pulmonary vascular involvement. And 18 (81.8%) patients with connective tissue disease were missed due to a lack of typical symptoms and physician understanding of disease before admission. Three (13.6%) patients had a misdiagnosis of idiopathic pulmonary arterial hypertension. The median time of diagnosis was 12 months. Conclusions Connective tissue disease may develop PE as the initial symptom. And some patients lack typical clinical manifestations of connective tissue disease. It should raise an alert with the physicians. Key words: Pulmonary embolism; Connective tissue disease; Disease attributes; Diagnostic errors