The case of a man with diagnosis of Kikuchi-Fujimoto disease (KFD) and catastrophic antiphospholipid syndrome (CAPS) is reported. He presented prolonged fever, lymphadenopathies, arthralgia, weight loss, hepatosplenomegaly and positive IgM for cytomegalovirus. While he was empirically treated with tuberculostatic drugs, he suddenly developed systemic inflammatory response syndrome, multiple organ failure and distal necrosis. On suspicion of severe sepsis, antibiotics, corticoids and recombinant human activated protein C (XIGRIS) were administrated. Exhaustive laboratory searching was negative. Histopathologic examinations of lymph node first disclosed malignant lymphoma but later KFD was confirmed. One month later, laboratory tests showed the presence of antiphospholipid antibodies (aPL). The patient was discharged after two months of hospitalization. This case exhibits a KFD complicated by definite CAPS. Cytomegalovirus could be involved in the development of both CAPS and KFD. Because of the severity of the case, we believe that XIGRIS noticeable improved the altered coagulation profile associated with CAPS.