Systemic lupus erythematosus is an autoimmune connective tissue disorder that affects multiple organs. While the clinical manifestations may vary in intensity over time and be associated with chronic disease, occasional cases occur where sudden and unexpected death has occurred. Cardiovascular disease is common, with accelerated atherosclerosis, intravascular thrombosis associated with antiphospholipid syndrome, and hypertensive cardiomegaly. Vasculitis with superimposed thrombosis may result in critical reduction in blood to vital organs, such as the heart and brain with infarction. Mesenteric ischemia may be caused by vasculitis, thrombosis, and accelerated atherosclerosis and may result in lethal intestinal infarction. Other diverse causes of sudden death include myocarditis, epilepsy, pulmonary hypertension, pulmonary thromboembolism, and sepsis. The autopsy evaluation of such cases requires careful examination of all organs with extensive histological sampling to include blood vessels, and microbiological sampling for bacteria, viruses, and fungi. (Published Abstract)