Lupus anticoagulant acquired hypoprothrombinemia syndrome in childhood: Two distinct patterns and review of the literature

Introduction: Lupus anticoagulant associated with acquired prothrombin deficiency also known as 'lupus anticoagulant hypoprothrombinemia syndrome' (LAHS) is an entity that is well described in adults and is usually associated with autoimmune conditions (LAHS-AI). However, in children, LAHS has unique features that are distinct from the adult type. Aims: We report two paediatric cases of LAHS, describe their distinct patterns and review the paediatric literature on LAHS. Methods: Case studies on two patients with LAHS were reviewed, details on their presentation, work up and management were extracted. A Medline search was conducted on LAHS in children between 1960 and 2014; Articles in languages other than English were excluded. Results: The case studies highlight the differences in the two patterns of childhood LAHS. Additionally the review of the literature reveals that there are 15 case reports and 5 case series that report 25 children with LAHS-AI, 9 case reports and 6 case series report 26 children of LAHS associated with viral infections (LAHS-VI). At presentation, all patients with LAHS-AI had positive laboratory tests for autoimmune diseases, most commonly for systemic lupus erythematosus while these tests were negative in LAHS-VI. All patients with LAHS-AI had a protracted course and needed prolonged treatment with immune-suppressive therapy while patients with LAHS-VI resolved spontaneously or needed short-term immune-modulating therapy. Conclusion: In childhood, two distinct patterns of LAHS are observed, either associated with infection or autoimmune disease. Initial diagnostic investigations are critical to differentiating these two patterns as the prognosis and outcome for each is distinct.