Rituximab use in pediatric lupus anticoagulant hypoprothrombinemia syndrome - report of three cases and review of the literature.

Lupus anticoagulant hypoprothrombinemia syndrome (LA-HPS) is a rare condition that may predispose both to thrombosis and bleeding due to positive lupus anticoagulant (LA) and factor II (FII) deficiency. It can be seen in association with infections or systemic lupus erythematosus (SLE) and may require glucocorticoids (GCs) and/or immunosuppressive medications. Pediatric LA-HPS cases in the literature and three cases that received only rituximab (RTX) for LA-HPS (in addition to GCs) at two institutions between January 2010 and June 2017 were analyzed descriptively. Pediatric LA-HPS cases (≤18 years) with bleeding or thrombotic events were included. Information obtained included demographics, presenting symptoms, diagnoses, treatments, pre-/post-treatment prothrombin time (PT)/partial thromboplastin time (PTT)/LA/FII levels, and outcomes. In addition to three LA-HPS cases identified at our institutions, as of June 2017, 37 articles reported 54 pediatric LA-HPS cases (mean age: 8 years (0.9-17 years); female/male: (2:1); viral illness 27 (50%), SLE 20 (37%), and other six (11%)). All cases had a positive LA and FII deficiency (range: 0%-40%). All cases presented with bleeding diathesis and were treated with various regimens, but there was no reported use of RTX. The purpose of this report is to describe the novel use of RTX as a steroid-sparing agent in three pediatric SLE cases and to systematically review the literature on pediatric cases of LA-HPS.