Abstract

Background: Pulmonary embolism is a clinical condition caused by the obstruction of the pulmonary artery and its branches with endogenous, exogenous embolism, or local thrombus formation. It is a rare but potentially life-threatening event in the pediatric population. Pediatric pulmonary embolism has many unknown characteristics.
Aims: To evaluate clinical features, genetic and acquired risk factors, diagnostic imaging, and treatment strategies with long-term results in children with pulmonary embolism.
Study Design: A retrospective multicenter clinical trial
Methods: Patients aged 0-18 years who were diagnosed with pulmonary embolism with computed tomography pulmonary angiography (CTPA) findings (intraluminal filling defect in the lobar or main pulmonary artery) in 3 university hospitals between 2006 and 2021 were included in the study. A form was created for data standardization, and variables were collected retrospectively through medical record review. In addition to the features given above, we also evaluated in situ pulmonary artery thrombosis (ISPAT) and patients’ Wells scores. Follow-up CTPA results were evaluated for patient response to treatment. Complete recovery means that there were no lesions, incomplete recovery if there was still embolism, and no response if there was no change.
Results: Twenty-four patients (female:13, male:11) were included in the study. The mean age was 13.5 years. All patients but one had at least one or more genetic or acquired risk factors. Factor V Leiden mutation (16.6%) was the most common genetic risk factor. Six of 16 patients with Doppler ultrasonography were diagnosed with ISPAT because there was no sign of thromboembolic thrombosis. Nine (41.6%) patients had a Wells score of >4 (pulmonary embolism clinically strong), and 15 (58.4%) patients scored <4 (pulmonary embolism clinically likely weak), indicating that an alternative diagnosis was more likely than pulmonary embolism (sensitivity %37.5). The mean follow-up period was 23 (±17) months. Complete and incomplete recovery was observed in 15 (62.5%) and 7 (29.1%) patients, respectively, among the patients who underwent follow-up evaluation. No response was obtained in 2 patients (8.3%) who died.
Conclusion: The Wells scoring system seems insufficient to diagnose pulmonary embolism in children and should be improved by adding new parameters. ISPAT may be more common in children with congenital heart disease and systemic disease.