Thromboembolism in paediatric lupus patients

Abstract

Paediatric patients with systemic lupus erythematosus (SLE) and antiphospholipid antibodies (aPL), specifically lupus anticoagulants(LAC) are at high risk of developingthromboembolicevents (TE). Our objectiveswere to determine the prevalenceof TE in paediatricSLE patientswith LAC and to determine if anticoagulation was effective to decrease morbidity, and prevent recurrent TE. We reviewed data on 149 paediatric SLE patients treated over 10 years. In all, 24 patients (16%) were LAC positive, and 21 TE occurred in 13 of these LAC positive patients (54% incidence of TE in LAC positive patients). The events were cerebral venous thrombosis (9), arterial stroke (3), deep venous thrombosis (4), pulmonary embolism (2), other venous event (1) and other arterial events (2). The median duration between SLE diagnosis and first TE was 15.2 months (range 0-62), and the median age at first TE was 15.1 years (range11.4-18.4). Long-termanticoagulationwas prescribed, and eight patients (62%) were transferred to adult care on lifelong oral warfarin; four (31%) remain under our care on lifelong warfarin, and one patient died of causes unrelated to her TE. No patient has been identified with deficiencies of protein C, protein S or antithrombinIII. One patient is heterozygousfor Factor V Leiden, and one is heterozygous for both the Prothrombin 20210A mutation and the MTHFR (methylene tetrahydrofolate reductase) mutation. Four patients had recurrent TE (31%), and three were not anticoagulated at the time of their second event. One patient had two recurrences on therapeuticanticoagulation.Thromboembolic events are prevalent in the LAC positive paediatric SLE population, and consideration for lifelong anticoagulation must occur after an initial TE.