PB0908 - Retrospective Case Series Study of non-oncology patients with thrombosis in a single Tertiary Paediatric centre in Malaysia

Background: In children, thrombosis is often underdiagnosed with only few studies reported in literature. Several factors contribute to incidence of thrombosis including genetic, underlying medical condition and environmental factors. Clinical implication of thrombosis is substantial and long term sequelae are common .Current recommendation for therapeutic range and duration of anticoagulant are extrapolated from the adult literature. However published experience with therapeutic low molecular weight heparin and clinical outcomes in pediatric are limited.

Aims: This study aimed to describe clinical features ,to identify the risk factors and the outcomes of thrombosis.

Methods: All patients aged < 18yrs diagnosed between January 2020 and December 2023 with thrombosis and managed by hematology oncology team at our center were retrospectively identified. Thrombotic events were confirmed by imaging. Frequency tables and continues summary statistics are presented for variables included in analysis. Oncology patients were excluded.

Results: We identified 24 patients with 26 episodes of thrombotic events. Age between Day 10 of life to 17 years old, male to female ratio was 1:0.4. The most common presentation are swelling and pain over affected sites (38% and 19% respectively). The veins are the most involved sites (!8) followed by arterial (5) cerebral sinuses (2) and right atrium. Infection and sepsis (11),central venous catheter (7) , dehydration (2) surgery (1) polycythemia (1) and vessel anomaly (1) are among risk factors identified. All received enoxaparin as anticoagulant and 1 patient required additional thrombolytic agent. The thrombus resolved in 17 events, became an organised clots in 2 events , and persistent and still on going treatment in 3 patients. Four patients died due to underlying diseases.

Conclusion(s): Multiple risk factors contributing to incidence of thrombosis in pediatric population especially Infection and central venous catheter. These findings may help clinicians to identify high risk patients and develop appropriate prevention strategies.