Prevalence and risk factors for pulmonary embolism in children with sickle cell disease: an institutional retrospective cohort study

The study was conducted to examine prevalence of pulmonary embolism in children with sickle cell disease (SCD) and identify potential risk factors associated with pulmonary embolism in a single tertiary paediatric centre.Children with SCD between 0 and 21 years of age from January 2010 to January 2021 were included. Pulmonary embolism was initially identified using International Classification of Diseases (ICD)-9 or 10 codes and confirmed with manual chart review of identified cases. Logistic regression analysis was performed to assess association between SCD specific and general thrombotic risk factors and pulmonary embolism.We identified 492 unique patients with SCD with a median age of 11 years (interquartile range: 4-18). A total of eight (1.6%) patients developed a pulmonary embolism. Patients with pulmonary embolism were significantly older (median, interquartile range: 20.5, 14-21 years) than patients without pulmonary embolism (median, interquartile range: 10, 4-17 years). Central nervous system (CNS) vasculopathy and erythrocytapheresis were significantly associated with pulmonary embolism on univariable logistic regression analysis. A previous diagnosis of deep vein thrombosis (DVT) was significantly more common among patients with pulmonary embolism than among those without pulmonary embolism (50 vs. 5.2%; P < 0.0001).Prevalence of pulmonary embolism in children with SCD was high. Risk factors associated with pulmonary embolism in this study such as CNS vasculopathy or erythrocytapheresis could suggest that the risk for pulmonary embolism in SCD may be related to the severity of disease state. Future studies are needed on pulmonary embolism prevention strategies.