Surviving Multiple Cardiac Arrests Secondary to Catastrophic Sero-Negative Antiphospholipid Syndrome: A Case Report
Authors: Hearn Andrew I , Ellet Tyler R , Pippas Andrew M , Nukala Suresh 
Published: December 2023

Antiphospholipid syndrome (APS) is an autoimmune disorder which predisposes to venous and arterial thrombosis due to the autoantibodies targeting phospholipids in cell membranes contributing to a pro-thrombotic state. The appropriately named catastrophic anti-phospholipid syndrome (CAPS) is distinguished from classical APS by the rapid involvement of 3+ organs, evidence of areas of small vessel occlusions, and significantly elevated anti-phospholipid titers (Cervera, 2018). To further complicate the matter, there is a growing body of evidence of the existence of sero-negative APS (SNAPS) that are negative for the classical lupus anticoagulant, anticardiolipin antibody (aCL), and anti-beta2 glycoprotein-I but may be positive for non-criteria APS antibodies. Presented below is a patient with SNAPS who responded to the therapy for CAPS despite negative classical autoantibodies.

A 34 year old man with a past medical history of chronic alcohol use presented to the ED with a two day history of worsening shortness of breath. The patient was found to have an spO2 of 45-50% on room air and was quickly transitioned to a non-rebreather and subsequently BIPAP. Initial CBC was significant for WBC 22.1, Hg 19.3, Hct 58.5, MCV 100.8, and platelets of 166 consistent with neutrophilic leukocytosis and macrocytic polycythemia. D-dimer &gt;20 was suggestive recent/on-going coagulation and/or fibrinolysis. Due to worsening respiratory failure, he was intubated and admitted to the ICU. While on 3 vasopressors he became bradycardic and a code blue was called for pulseless electrical activity (PEA). After 3 rounds of CPR he achieved return of spontaneous circulation (ROSC) and was taken for urgent CT imaging. After arriving in the radiology department he went into cardiac arrest for two rounds of CPR before achieving ROSC and being scanned and returning to the ICU. Polycythemia tests were drawn which revealed elevated erythropoietin of 52.1 (2.6-18.5) and ultimately negative JAK2. Chest CTA was significant for a PE with a heavy clot burden involving the entire right lung and the left upper and lower lobes. CT C/A/P showed findings of bilateral lower lobe pneumonia, severe gastritis, pancolitis, proctitis, pancreatitis with a 4.6cm pseudocyst, and fatty liver with congestive enhancement. Tissue-type plasminogen activator (tPA) bolus and infusion was initiated based on the imaging findings with the third cardiac arrest occurring 7 minutes later early in the morning. Repeat CBC revealed an Hgb/Hct of 22.2 g/dL and 71.5%, respectively, with a significant drop in platelets down to 103 with occasional large platelets consistent with peripheral destruction of platelets was noted on peripheral blood smear (PBS). Therapeutic phlebotomy of 300mL was subsequently performed with two additional cardiac arrests within 2 hours of each other before vascular surgery was able to perform thrombectomies of the involved pulmonary arteries and initiate catheter-directed thrombolysis. Platelet count dropped while on heparin to 25,000 so a HIT panel was ordered and he was transitioned to argatroban.

At this point hematology was consulted who was concerned for CAPS and ordered aPL (anti-phospholipid) tests along with an appropriate panel of labs to rule out alternative causes. Peripheral blood smear did not reveal fragmentation of RBC to suspect TTP. Tests for ACL IgG/IgM and anti-beta2GPI IgG/IgM antibodies, COVID, HIV, ADAMTS deficiency, hereditary thrombophilia, and ANA were negative. High-dose steroids and daily plasma exchanges via vascath was initiated and within 12 hours there was significant improvement. He was extubated and off pressors in 24 hours with improved platelets. Lupus anticoagulant test results were reported after discharge with dVVT mix and PTT LA mix both being prolonged, however, repeat lupus anticoagulant 3 months later was negative.

Given the potentially catastrophic effects of a missed CAPS diagnosis, a high level of clinical suspicion is needed as plasma exchange can quickly alleviate an otherwise disastrous condition. Further research into non-criteria APS autoantibodies (IgA)may be able to help guide future SNAPS diagnoses.