ABSTRACT
Antiphospholipid syndrome is a disease presenting with arterial/ venous thrombosis and obstetrical complications. Pulmonary embolism is an important pulmonary complication of antiphospholipid syndrome, whereas, intra-alveolar hemorrhage is a rarely encountered manifestation. Hemophilia B is caused by factor IX deficiency that results in prolonged oozing after injuries and/or surgery, and delayed or recurrent bleeding prior to complete wound healing. Antithrombotic therapy may be used for recurrent hemostatic attacks in APS; but if there is a hemostatic defect, it may lead to serious bleeding complications. Here, we present a case of antiphospholipid syndrome accompanied by heterozygote methylene tetrahydrofolate reductase gene mutation [MTHFR] mutation and hemophilia B