Protein S Deficiency and Pulmonary Embolism in Children: A Case Report and Review of Literature

Othman Rizk A Mishref

doi:10.31031/rpn.2021.05.000614

Abstract

Protein S Deficiency and Pulmonary Embolism in Children: A Case Report and Review of Literature

Highlights

Heterozygous carriers may manifest at a later age; homozygous Protein S deficiency (PSD) can lead to an early thrombotic onset in the neonatal or infant period
It is important for pediatrician to consider pulmonary embolism as a differential diagnosis for young patients presenting with severe unexplained parasternal chest pain with strong family history of thrombophilia and to have a low threshold for requesting appropriate investigations
Children presented with pulmonary embolism in the absence of precipitating factors need to be tested to identify whether there is a deficiency of protein C (PC), PS, or antithrombin III (AT III)

Summary

Background

Heterozygous carriers may manifest at a later age; homozygous PSD can lead to an early thrombotic onset in the neonatal or infant period. Type II (qualitative PS deficiency) is characterized by normal PS levels but reduced PS activity due to a dysfunctional PS variant in plasma. Type III PS deficiency is characterized by low levels of free PS, though the total plasma concentration of PS is normal [8]. VTE occurs when ≥1 component of Virchow’s triad is activated: stasis of blood flow, injury to the endothelial lining, and hypercoagulability of blood components. This is the most useful pathophysiological construct for thinking about thromboembolism in children [2]. Protein S (PS) deficiency contributes to 2% of all venous thromboembolisms presenting to accident and emergency and its deficiency is a major risk factor for venous thrombosis [3]. In asymptomatic individuals with PS deficiency, the prophylaxis of VTE should be done in the presence of a major acquired risk factor for thrombosis [9]

Findings

Discussion

Summary