Saraiva BSAlves ECSousa A1Borges MACosta MS-MBaptista RBBatalha SMaia RNeto GKjöllerström PFrancisco T2025-08-262025-08-262024Acad J Ped Neonatol 2024; 14(1): 555934http://hdl.handle.net/10400.17/5142Introduction: Nephrotic syndrome (NS) is associated with a multifactorial hypercoagulable state. Congenital NS (CNS) exhibits a higher prevalence of thrombotic events compared to other types. Direct oral anticoagulants (DOAC) have been approved for paediatric acute venous thromboembolism. Case Report: We present 2 CNS children treated with rivaroxaban for treatment (Case 1) and prophylaxis (Case 2) of thrombotic events. A 2-month-old male previously diagnosed with CNS with homozygous mutation in the NPHS1 gene, underwent central venous catheter (CVC) replacement during which multiple thrombi were seen. The patient developed clinical signs compatible with pulmonary embolism. Chest radiograph showed a peripheral condensation on the left hemithorax and CT-angiography was inconclusive for peripheral embolism. Despite therapeutic doses of enoxaparin, adjustments were difficult with persistently low anti-Xa levels. The switch to rivaroxaban was performed, and doses were regularly adjusted based on patient’s weight. No adverse or other thrombotic events were reported, despite maintaining CVC. As expected, chronic kidney disease progressed at 19 months and rivaroxaban was suspended. An 8-month-old female with CNS associated with an heterozygous mutations in the NHPS1 gene, underwent multiple CVC replacements due to recurrent obstruction despite heparinisation and alteplase administrations. Although there were no systemic thrombotic episodes, considering the high risk of thrombosis, prophylaxis with rivaroxaban was initiated with eGFR of 54 mL/min/1.73m2 (1-2 SD below expected eGFR). Weight-adjusted dose was prescribed. No severe adverse or thrombotic events reported until 19 months. Conclusion: These cases suggest that the safety and efficacy profile of rivaroxaban may be encouraging for treating and preventing venous thromboembolism in CNS. However, additional studies are warranted to optimize DOAC use in children with complex conditions, such as CNS, allowing for more tailored management of anticoagulation in this high-risk population.engCongenital nephrotic syndromeNPHS1RivaroxabanThromboembolismHDE NEF PEDHDE HEM PEDtext10.19080/AJPN.2024.14.555934