BackgroundAntiphospholipid syndrome (APS) is an autoimmune disease characterized by the occurrence of venous and/or arterial thrombosis, and the detection of circulating antiphospholipid antibodies. The classification criteria for definite APS are actually met when at least one clinical criterion (thrombosis or pregnancy morbidity) is present in association of one laboratory criterion (LAC, aCL antibody or aβ2GPI antibody present on two or more occasions, at least 12 weeks a part), and thrombosis should be confirmed by objective validated criteria. The average age of primary APS patients has been reported to be about 35–40 years and the disease is more common in women than in men.Case presentationIn this report, we described a rare case of an adult male who presented over a period of 9 years with a wide spectrum of clinical manifestations involving different organs that were not initially diagnosed as APS. Dizziness and syncope were his first clinical symptoms, and a non-bacterial thrombotic endocarditis (NBTE) involving the mitral valve was at first diagnosed. Subsequently, the patient also presented with generalized seizures and subsequent head injury. When the patient was admitted to our clinic with bilateral epistaxis and fever, thrombocytopenia was revealed. Moreover, laboratory examinations showed acute pancreatitis with an increase of levels of inflammation markers.ConclusionBased on the patient’s medical history and all the examination results, it was possible to make a diagnosis of primary APS and, starting from diagnosis of thrombocytopenia, we were allowed to conclude that all of manifestation were epi-phenomena of a unique clinical entity, rather than unrelated diseases. Though APS is one of the most common thrombocytophilias, unfortunately, it is not recognized often enough. The lack of prevention in undiagnosed patients may cause severe complications which can in turn result in the death of those patients.