Lower-extremity swelling is an uncommon presentation in a pediatric emergency department. Deep venous thrombosis is one of the common differential diagnoses in a patient with an underlying predisposing factor. We report a case of a previously healthy adolescent without any risk factor for thromboembolism presented with deep venous thrombosis. The pertinent literature is reviewed.

An adolescent with lower-extremity swelling.

Venous thromboembolic complications (VTE) in children: first analyses of the Canadian Registry of VTE

background

Antithrombotic therapy in children: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy.

Background A high frequency of asymptomatic pulmonary embolism (PE) has been reported in patients with deep venous thrombosis (DVT) in studies of a limited number of patients using varying criteria for lung scan assessment. Objectives To estimate the frequency of PE using systematic lung scans in a large group of outpatients with DVT and to compare the results using varying lung scan assessment criteria. Methods An international multicenter study comparing 2 different regimens of low-molecular-weight heparin nadroparin in DVT: perfusion lung scans were performed in 622 outpatients with no clinical indication of PE and with proximal DVT confirmed by venography. Three hundred seventy-nine of these patients underwent ventilation lung scans. High-probability (HP) scans for PE were assessed separately using either ventilation scans or chest radiographs to define mismatched perfusion defects. Results Perfusion scans showed abnormalities in 82% of the patients; 59% had segmental defects and 30% had normal scans or scans with a very low probability of PE. Depending on the criteria used, 32% to 45% had HP scans for PE; these percentages were higher in young patients. No relationship was found between extent of thrombosis and HP scans. The estimated frequency of silent PE was 39.5% to 49.5%. During a 3-month follow-up period during which the patients received therapy, the rate of PE recurrence was low (1.3%) and did not differ between patients with baseline HP scans and those with normal scans. Conclusions Regardless of what interpretative criteria are used for assessing lung scans in PE, the frequency of silent PE is 40% to 50% in patients with DVT. A baseline lung scan may easily detect PE in these patients but is not useful for predicting early thromboembolic recurrences that may occur during therapy.

https://jamanetwork.com/journals/jamainternalmedicine/articlepdf/485214/ira81023.pdf

An adolescent with lower-extremity swelling.

References

Venous thromboembolic complications (VTE) in children: first analyses of the Canadian Registry of VTE

Antithrombotic therapy in children: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy.

Systematic Lung Scans Reveal a High Frequency of Silent Pulmonary Embolism in Patients With Proximal Deep Venous Thrombosis

Venous thromboembolic complications in children

Determination of risk factors for deep venous thrombosis in hospitalized children