A 22-year-old man presented to his family physician with intense pain in, dusky discolouration of and reduced sensation to his right foot. He had a history of migraines and 2 years of mild intermittent calf discomfort with exercise, for which he had not sought medical attention. He had a family history of premature coronary artery disease. Peripheral artery duplex ultrasonography showed reduced blood flow in both tibial arteries and a deep vein thrombosis in his right leg. Given the abnormal arterial flow, computed tomography (CT) angiography was ordered, which showed a chronic occlusion in the patient's right superficial femoral artery and an occluded infrarenal abdominal aorta with collateralization (Figure 1). Splenomegaly and axillary adenopathy were noted. He was treated with apixaban and referred to the vascular surgery team.
The vascular surgery team considered performing an aortobifemoral bypass and referred the patient to the internal medicine team for preoperative assessment. Because the patient did not have any clear provoking factors for his unusual arterial and venous thromboses, such as cancer, antiphospholipid antibody testing was ordered and was positive for lupus anticoagulant, and for high levels of immunoglobulin (Ig) G anticardiolipin antibodies and IgG anti-[beta]2 glycoprotein-1 antibodies (a[beta]2GP1). He was referred to our hematology and rheumatology clinics. Besides apixaban, he was taking no other medications.
The patient recalled 6 months of insidious migratory arthralgia, prolonged morning stiffness and symptoms of Raynaud phenomenon. A few years before initial presentation, he had developed pleuritic chest discomfort, which was attributed to costochondritis, but the pain had never fully resolved. When we examined him, his body mass index was 31, his blood pressure was 140/85 mm Hg and he had dependent rubor and loss of hair on his right leg. Several joints were tender. We did not observe any swollen joints, head or neck adenopathy, or rashes.
Given that the patient's symptoms, thromboses and laboratory results suggested systemic lupus erythematosus (SLE), immune serology was ordered, which showed an antinuclear antibody titre greater than 1:640; antichromatin, anti-Smith and antiribonucleoprotein antibodies; elevated anti-double-stranded DNA; hypocomplementemia; and a positive direct antiglobulin test, without evidence of hemolysis (Table 1).
We diagnosed SLE with secondary antiphospholipid syndrome (APS) and started hydroxychloroquine (400 mg/d). We stopped apixaban and started long-term warfarin (target international normalized ratio [INR] 2-3). The patient's leg claudication and hypoesthesia improved without operative intervention. Because of his chronic pleuritic chest discomfort, we ordered CT pulmonary angiography to look for a pulmonary embolism. We did not find any emboli, but observed a large pericardial effusion, which we thought was likely caused by his lupus. We treated him with intravenous steroids followed by a tapering course of prednisone. We added mycophenolate mofetil (1 g, twice daily) as a steroid-sparing agent, and his chest pain and arthralgia rapidly resolved.
Despite immunosuppression, the patient subsequently developed progressive chest and neck discomfort that was different from his previous chest discomfort, suggesting a non-inflammatory cause. Given his underlying APS and known arterial disease, we were concerned about coronary artery disease and referred him to a...