Severe acute respiratory syndrome (SARS) is now known to be caused by a novel coronavirus, the SARS-associated coronavirus (SARS-CoV) (1). It is characterized by severe systemic symptoms in multiple organs, such as lung, immune system, and small vessels, and finally becomes respiratory failure. Initial autopsies reported the predominant pathological findings to be diffuse lung injury, injured immune organs, inflammatory response in systemic small vessels, and general toxic reaction (2).
Changes in coagulation and the development of thrombi have been reported in patients with SARS, but the extent of the effects of the SARS-associated coronavirus on the systemic circulation has yet to be established. Limited data are available on the extent of the damage to the systemic vasculature and circulation in patients with SARS. In the present study, an autopsy was performed on a 57-year-old man diagnosed with SARS and specimens from multiple organs were analyzed to assess pathological changes in the vasculature. Specimens from multiple organs, including the lungs, heart, liver, kidneys, adrenal glands, spleen, esophagus, stomach, intestine, vermiform appendix, pancreas, brain, cerebellum, brainstem, hilus of lung, mesenteric lymph node, and muscle tissues, were analyzed by light microscopy. Examination of all of the specimens revealed systemic circulatory disturbance and polyangiitis. Proliferation, swelling, and apoptosis of endothelial cells, and edema, inflammatory cell infiltration, and fibrinoid necrosis were observed in the walls of small blood vessels in specimens from the lungs, heart, liver, kidneys, adrenal glands, brain, gastrointestinal tract, and muscle tissues. In addition, thrombi were evident in the veins and microcirculation of the soft tissues surrounding the lungs, spleen, pancreas, kidneys, adrenal glands, and mesenteric lymph nodes (Figure 1A–1F).
This autopsy case report has demonstrated that in addition to the well-established diffuse alveolar damage and damage to the immune system, SARS is associated with systemic circulatory disturbance and polyangiitis, in particular thrombosis in the veins and microcirculation in multiple organs and tissues. To our knowledge, this is the first study to show the extent of the damage to the vasculature and circulation that can occur in patients with SARS.
Deep vein thrombosis and/or pulmonary embolism have been reported in patients with SARS previously (3, 4). However, the pathogenesis of deep vein thrombosis in patients with SARS remains unknown. Emerging evidence suggests that viral infection may have a role in the onset of venous thromboembolism (5, 6). The present study adds to this evidence by demonstrating widespread thrombosis associated with SARS.