(745) Catastrophic Antiphospholipid Syndrome: A Rare Cause of Refractory Diffuse Pulmonary Hemorrhage

Introduction: Catastrophic antiphospholipid syndrome is a severe acute onset clinical syndrome defined by the presence of acute multiorgan thrombosis (at least 3 organ systems) with small vessel microangiopathy and can lead to significant morbidity and mortality. Here, we present a case of lethal pulmonary hemorrhage due to Catastrophic Antiphospholipid Syndrome (CAPS) in a pediatric patient.

Description: A 17 year old female presented with headache, nausea, and vomiting. Computed tomography showed extensive cerebral venous thrombosis with subarachnoid and intraparenchymal hemorrhage and was intubated for declining mental status. Later that day, she developed massive pulmonary hemorrhage. There was strong clinical suspicion for pulmonary embolism at the time, but the hemorrhage and resulting hypoxia were refractory to anticoagulation reversal, endotracheal epinephrine, and all ventilator maneuvers. As a result, the patient passed from hypoxic cardiac arrest. Eventually, lupus anticoagulant resulted as positive and extensive thrombi in the lungs, kidneys, and brain were found on autopsy, leading to diagnosis of CAPS.

Discussion: Catastrophic Antiphospholipid Syndrome is a rare entity in pediatrics, with 45 documented cases in the CAPS Registry as of 2013. There is minimal data on its actual prevalence; this is likely due to the difficulty of diagnosis. The onset symptomatology is widely varied, and pulmonary hemorrhage is estimated to occur in about four percent of pediatric patients with CAPS. Additionally, unlike in adults where CAPS is the presenting syndrome of APS in approximately forty-five percent of patients, it is the presenting syndrome in eighty-six percent of pediatric patients. Triple therapy of anticoagulation, steroids, and plasma exchange are the mainstay of treatment. Prompt diagnosis is crucial in these patients as their coagulopathy is refractory to hemostatic treatments, which makes the development of complications such as pulmonary hemorrhage particularly dangerous. In fact, some sources list a mortality rate of somewhere between thirty and fifty percent. This case highlights the importance of prompt identification of CAPS and need for high clinical suspicion for APS in patients with extensive thromboses.