A 30‐year old woman presented to the emergency department with chest discomfort and shortness of breath along with heavy menstrual bleeding for 3 days. She noted a history of 2 late first (?) trimester fetal losses. Her laboratory studies were remarkable for hemoglobin of 6 g/dL, platelet count 90,000/mm3, which dropped to as low as 19,000/mm3 by day 3. Peripheral smear revealed hypochromic and microcytic anemia without schistocytes. Iron studies done revealed iron deficiency anemia. Liver function tests, hemolytic panel, normal PT but elevated PTT (43 seconds, normal: 25‐31 seconds), urine drug screen, pregnancy test, EKG, chest radiography, and echocardiogram were all normal. CT scan of the chest and abdomen showed a new splenic infarct. Doppler ultrasound of the lower extremity was negative for thrombosis. Autoimmune workup done for her anemia, menorrhagia and history of fetal loss revealed positive anticardiolipin antibody IgG (>100) and lupus anticoagulant that failed to correct after mixing study. Beta‐2 glycoprotein, heparin induced thrombocytopenia antibody panel, factor V Leiden mutation, antithrombin III, protein C, and protein S, and prothrombin gene were all normal. Evaluation for connective tissue disease including rheumatoid arthritis and SLE were negative. She was treated with packed red blood cell transfusion and iron. Her low platelet and bleeding was thought to be due to antiphospholipid antibody syndrome (APS) and was treated with 4 days dexamethasone. She had significant improvement in her anemia and thrombocytopenia within 1 week. The lupus anticoagulant and anticardiolipin antibody tested 16 weeks later were again positive. Warfarin was started when platelet counts were stable, and lifelong anticoagulation was advised.
Antiphospholipid antibody syndrome is an autoimmune hypercoagulable disorder associated with both venous and arterial thromboembolism. Cerebrovascular infarction is the most common event within the arterial circulation, whereas lower limb DVT and PE are the main sites within the venous circulation. Diagnosis of APS in our case was made using modified Sapporo criteria. Our patient had 2 clinical parameters (vascular thrombosis and pregnancy morbidity) and 2 of 3 laboratory parameters (presence of IgG or IgM anticardiolipin antibody in high titer [>40 U], antibodies to beta 2 glycoprotein I and lupus anticoagulant antibody detected initially and at a 12‐week interval). Thrombocytopenia (platelet count > 50,000) is frequently found in APS (20%–45% cases) and is of no clinical significance. However, severe thrombocytopenia (<50,000 or bleeding) is uncommon in APS and is treated using steroids, similar to ITP.
Severe thrombocytopenia and bleeding in APS are managed using steroids followed by anticoagulation after stabilization of platelet count.
To cite this abstract:Aryal M. Antiphospholipid Antibody Syndrome with Severe Thrombocytopenia: A Conundrum in Anticoagulation. Abstract published at Hospital Medicine 2013, May 16-19, National Harbor, Md. Abstract 476. Journal of Hospital Medicine. 2013; 8 (suppl 2). https://www.shmabstracts.com/abstract/antiphospholipid-antibody-syndrome-with-severe-thrombocytopenia-a-conundrum-in-anticoagulation/. Accessed April 10, 2020.