Abstract
【Background】Although the incidence of pulmonary thromboembolism caused by renal vein
thromboembolism is extremely low in pediatric SLE, it may be a fatal complication regardless of treatment.
Lp（a） is well-recognized lipoprotein related to developing venous thromboembolism. We evaluated the
clinical significance of elevated Lp（a） based on our case which developed thromboembolism.
【Case presentation】The case was a 14-year-old SLE girl who had been being follow-up at our
department and was hospitalized for a complaint of right flank pain. She developed SLE at the age of six and
had a history of lupus nephritis class II（ ISN/RPS） and recurrent lupus enteritis. It was already confirmed
that the levels of Lp（a） were more than 30mg/dL prior to the onset of thromboembolism.
Laboratory findings included elevated D-dimer and thrombocytopenia, as well as hypoalbuminemia
and proteinuria due to nephrotic syndrome, but she had no laboratory findings suggestive of antiphospholipid
antibody syndrome. Chest/abdominal contrast CT examination revealed a contrast defect due to
thromboembolism in the left pulmonary artery and right renal vein. The thrombolysis for emboli was
performed for five months and the thromboembolism did not recur following the completion of therapy.
【 Conclusions】Although it is hard to associate a causality based on our case report, elevated Lp（a） as
a genetic predisposition to hemostasis may be associated with renal vein thromboembolism. It was suggested
that it is important to check the Lp（a） level as a predictive factor for renal vein thromboembolism and to be
careful follow-up the SLE patients with increased Lp（a）.
