Catastrophic antiphospholipid syndrome in childhood: presentation with an inferior caval vein mass.

Venous thromboembolism remains one of the important causes of pulmonary hypertension in children. The causes of venous thromboembolism are varied and include antiphospholipid antibody syndrome (APS). Catastrophic APS (CAPS) is a severe variant of APS characterised by disseminated thrombosis and microangiopathy resulting in multiorgan failure. CAPS can occur independently (primary APS) but mainly occurs in association with systemic lupus erythematosus including the paediatric population. We report a young girl with primary CAPS who presented with pulmonary hypertension and an inferior vena cava mass masquerading as a tumour.