title: Catastrophic APS in the context of other thrombotic microangiopathies.
abstract: The catastrophic antiphospholipid syndrome (CAPS) is a rare disease that affects 1 % of cases with antiphospholipid syndrome (APS). CAPS can mimic or overlap with different thrombotic diseases; many patients present with a microthrombotic storm or thrombotic microangiopathic hemolytic anemia (TMHA). Thus, the differential diagnosis of CAPS includes thrombotic thrombocytopenic purpura (TTP), typical and atypical hemolytic uremic syndrome (HUS), systemic infections, malignancies, pregnancy-related disorders, malignant hypertension, heparin-induced thrombocytopenia, and drug-induced thrombotic microangiopathies. Antiphospholipid antibody (aPL) positivity has been proposed as the clue in this differential diagnosis; however, aPL can also occur in healthy people and in those with infections or malignancies. Thus, the differential diagnosis of an aPL-positive patient presenting with a microthrombotic storm is broad; the workup should include a special attention to signs of infection and disseminated malignant disease, assessing the funduscopic signs of malignant hypertension, testing ADAMTS13 activity and anti-heparin-platelet factor 4 (HPF4) antibodies, and searching previous exposure to certain drugs. This article aims to review the main diseases included in the differential diagnosis of CAPS in the context of other thrombotic microangiopathies.
authors.affiliation: Department of Autoimmune Diseases, Institut Clínic de Medicina i Dermatologia, Hospital Clínic, Barcelona, Catalonia, Spain.
authors.forename: Ignasi
authors.initials: I
authors.lastname: Rodríguez-Pintó
authors.forename: Gerard
authors.initials: G
authors.lastname: Espinosa
authors.forename: Ricard
authors.initials: R
authors.lastname: Cervera
mesh_terms: D016736:Antiphospholipid Syndrome / Q000150:complications* / Q000175:diagnosis*; D003937:Diagnosis, Differential; D005260:Female; D006463:Hemolytic-Uremic Syndrome / Q000150:complications / Q000175:diagnosis; D006801:Humans; D006974:Hypertension, Malignant / Q000150:complications / Q000175:diagnosis; D007239:Infections / Q000150:complications / Q000175:diagnosis; D009369:Neoplasms / Q000150:complications / Q000175:diagnosis; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000175:diagnosis; D011697:Purpura, Thrombotic Thrombocytopenic / Q000150:complications / Q000175:diagnosis; D057049:Thrombotic Microangiopathies / Q000209:etiology*