INTRODUCTION:Antiphospholipid antibody syndrome (APS) is an autoimmune disorder with protean manifestations. It is characterized by the presence of antiphospholipid antibodies in association with arterial or venous thrombosis, recurrent spontaneous abortions or thrombocytopenia. APS can be primary, or secondary in association with diseases such as Systemic Lupus Erythematosus and Human Immunodeficiency Virus. Catastrophic APS (CAPS) is a rare, frequently fatal, accelerated form of APS. Diagnosis of CAPS requires simultaneous development of histopathologic small vessel occlusion in at least three organ systems in the presence of antiphospholipid antibodies. We report a case of CAPS as an initial presentation of a stage IV pulmonary adenocarcinoma.
CASE PRESENTATION:A 60-year-old Caucasian man presented to our institute with a 1-day history of right lower extremity pain and numbness. On inquiry, he revealed a several week history of increased dyspnea, a productive cough of white sputum, pleuritic chest pain, and a 20-pound weight loss. His past medical history was significant for COPD. On exam, the patient was afebrile, tachycardic and mildly dyspneic. The chest was remarkable for reduced breath sounds on the right side. The right leg was cold and painful, and the popliteal, posterior tibialis and dorsalis pedis pulses were non-dopplerable. The remainder of the physical exam was non-contributory. Blood tests showed an elevated WBC of 15K/cmm, a macrocytic anemia (hematocrit 37% with a MCV of 96 fL) and a normal platelet count and chemistry. Arterial blood gas on 2 liters of supplemental oxygen revealed a combined respiratory and metabolic acidosis along with moderate hypoxemia (pH: 7.26, PaC02: 45mmHg, Pa02: 63mmHg). Coagulation profile showed a mildly prolonged PT (16 seconds) and a normal aPTT. Chest radiograph demonstrated an acute pleural effusion in the right hemithorax as well as advanced emphysematous changes. This patient was diagnosed with acute arterial insufficiency of his right lower extremity and underwent immediate operative evaluation. Intraoperative angiogram revealed acute and chronic thrombosis of the entire right lower extremity arterial tree. After successful embolectomy, heparin therapy was initiated. The patient developed immediate post-operative hypotension and hypoxemic respiratory failure requiring intubation and mechanical ventilation. Subsequent chest radiograph showed an enlarging pleural effusion, and an echocardiogram revealed a large circumferential pericardial effusion associated with right atrial compression. Therapeutic thoracentesis and pericardiocentesis revealed a large amount of bloody fluid with cytopathology suggestive of underlying malignancy. On hospital day 14, the platelet count acutely decreased to 38K/cmm suspicious for heparin-induced thrombocytopenia. Despite the initiation of argatroban as well as undergoing a right above-the-knee amputation for persistent clot, the patient’s condition deteriorated. On hospital day 17, he was diagnosed with thromboses in his right upper extremity, left lung, left kidney and spleen. A lupus anticoagulant antibody was ordered and returned positive; thus, establishing the diagnosis of CAPS. The patient was immediately treated with pulse dose steroids and intravenous immunoglobulins. Unfortunately, the patient succumbed to his disease on hospital day 24. Post-mortem exam revealed widely metastatic adenocarinoma of pulmonary origin with the most prominent foci of tumor arising from within the pericardial sac. There was evidence of vascular infarcts in the lung, kidney and spleen.
DISCUSSIONS:The pathogenesis of CAPS is not completely understood. As seen in our patient, the widespread vascular thromboses can have devastating consequences. Although APS has been associated with hypercoagulable states arising from solid tumors, CAPS heralding a malignancy is rare. The International Registry, established by the European Forum in 2000 and considered the most comprehensive collection of data on CAPS, lists only two patients who have suffered CAPS as the initial manifestation of a primary lung malignancy.
CONCLUSION:Our case suggests that in patients presenting with CAPS, an evaluation for occult malignancy would be prudent.
DISCLOSURE:Cameron Huxford, None.