Risk factors for pulmonary embolism in patients preliminarily diagnosed with community-acquired pneumonia: a prospective cohort study

Abstract

D-dimer levels are increased in patients with acute pulmonary embolism (PE). However, D-dimer levels are also increased in patients with community-acquired pneumonia (CAP). The aim of this prospective cohort study was to examine the incidence and clinical features of patients preliminarily diagnosed with CAP and with increased D-dimer levels, and who finally were diagnosed with PE. Patients diagnosed with CAP and hospitalized in the Respiratory Department of the Tenth People's Hospital Affiliated to Tongji University between May 2011 and May 2013 were enrolled. D-dimer levels were measured routinely after admission. For patients with increased D-dimer levels, those suspected with PE underwent computed tomography pulmonary angiography (CTPA). A total of 2387 patients with CAP was included: 724 (30.3 %) had increased D-dimer levels (median of 0.91 mg/L). CTPA was performed for 139 of the 724 patients (median D-dimer levels of 1.99 mg/L). Among the 139 patients, 80 were diagnosed with PE, and 59 without PE; D-dimer levels were 2.83 and 1.41 mg/L, respectively (p < 0.05). Multivariate analysis showed that age, coronary heart disease, chronic obstructive pulmonary disease (COPD), lower limb varicosity, chest pain, shortness of breath, hemoptysis, fever, and increased levels of troponin I were independent risk factors for PE. Presentation of PE and CAP are similar. Nevertheless, these results indicated that for hospitalized patients with CAP and elevated D-dimer levels, PE should be considered for those >60 years; with CHD, COPD, or lower limb varicosity; with chest pain, shortness of breath, hemoptysis, increased troponin I, or low fever.

Efficacy and safety of low‐dose urokinase for the treatment of hemodynamically stable AECOPD patients with acute pulmonary thromboembolism

“…Systemic inflammatory response and chronic anoxia in COPD could cause polycythemia, pulmonary vascular contraction, pulmonary hypertension and hypercoagulable state blood, which might increase the PTE risk. However, the co‐existence of PTE with COPD was also recognized as a common cause for AECOPD . Pulmonary hypertension usually took place when vascular obstruction in PTE patients was more than 30%.…”

“…Pulmonary thromboembolism (PTE) refers to a thromboembolus mainly from lower extremity deep venous or right ventricle filling a main pulmonary artery or its branches. Acute PTE causes a series of severe respiratory and circulatory symptoms due to pulmonary artery obstruction, such as pulmonary hypertension, acute corpulmonale, dyspnea, lower blood pressure, shock and even sudden death …”

“…It is always a dilemma to differentiate acute PTE from AECOPD, especially AECOPD with acute PTE (AECOPD‐PTE), due to their similar clinical symptoms. Some articles reported that AECOPD was a major risk factor for PTE because of COPD patients' advanced age and long‐term bedridden . Further studies demonstrated that both the prevalence and the incidence of PTE or other venous thrombosis in AECOPD patients were much higher than non‐COPD patients, reaching up to 20%‐60%.…”

Incidence of Pulmonary Embolism in Patients with Positive D-Dimers and Chest X-ray Evidence of Pneumonia: A Retrospective Study

“…Zhang Z et al looked at 139 patients carrying the diagnosis of community-acquired pneumonia who had elevated D-dimers and who underwent CT angiography [12]. Fully 66% were diagnosed with PE in their series.…”

Anatomic and clinical risk factors for pulmonary embolism in patients with deep venous thrombosis of the lower extremity

“…In one study, 36 of 794 patients (5%) had coexisting pneumonia [14]. In a retrospective cohort study, 724 of 2,378 patients (30.3%) hospitalized with community acquired pneumonia displayed increased D-dimer levels [15]. …”