PB0624 - Post-thrombotic syndrome in children with incidental thrombosis.

Background: The rate of deep vein thrombosis (DVT) in hospitalized children in increasing (1). In general, asymptomatic DVT is an incidental finding, and the evidence about frequency, complications and long-term outcomes are often presented together with symptomatic episodes, so the problem of incidental thrombosis seems to be undervalued (2).

Aims: To evaluate the differences in patient-related characteristics and in frequency and severity of post-thrombotic syndrome (PTS) in children with аsymptomatic thrombosis, who did not receive treatment compared to children, who have assessed treatment.

Methods: We have retrospectively analyzed the medical records of 48 patients from 0 to 17 years (at the time of thrombosis) from 2013 to 2023 of our tertiary care Centre and selected patients with objectively confirmed asymptomatic DVT. 88% oh children were cancer patients. All patients were divided into 2 groups: patients, who did not receive antithrombotic treatment (G1, n=13) and who assessed therapy (G2, n=35). Then we analyzed the data of PTS assessment in these patients. PTS was measured using Manco–Jonson Instrument (MJI), Modified Villalta Scale (MVS), the Clinical Assessment of Post-Thrombotic Syndrome (CAPTSure). Chi-square test was used to assess the statistical significance of differences between groups.

Results: Most of DVTs (96%) were in the veins of upper extremity, 27% of thrombosis were occlusive. There were no statistically significant differences between G1 and G2 (see table 1), especially in severity and frequency of PTS. The overall frequency of PTS was 46% using MVS/MJI and 29% using CAPTSure. Majority of children had mild PTS, the most common symptom was the presence of collaterals. There was 1 patient with moderate PTS in G2.

Conclusion(s): The overall frequency of PTS in patients with asymptomatic thrombosis was similar to the incidence of PTS in patients with symptomatic DVT in the published data (3;4). However, most patients had mild PTS and slight clinical sings.