Pathophysiology and Biomarkers of Secondary Multiple Organ Dysfunction Syndrome

Background: Secondary multiple organ dysfunction syndrome (MODS) has an excessively high fatality rate. The mechanisms by which sepsis and systemic inflammatory response syndrome (SIRS) induces organ dysfunction and their characteristic pathological findings and biomarkers are not fully understand. Methods: We examined 24 autopsy cases with secondary MODS and peripheral blood (PB) from 467 patients with SIRS and MODS. Results: PB cytology (presence of large scavenger receptor A-positive (SRA+) cells and an SRA index >30), systemic capillary injury, pulmonary symptoms (accumulation of neutrophils and platelet thrombi, alveolar epithelial injury and edema) and cardiac symptoms (accumulation of neutrophils and platelet thrombi, capillary injury and contraction band necrosis) were assessed for all of the cases. The 467 patients were classified into group A (negative for large SRA+ cells), group B (positive for large SRA+ cells, and SRA index <30) and group C (positive for large SRA+ cells, and SRA index >30). Group C patients exhibited a significantly lower survival rate (p < 0.001). Conclusions: It was concluded that: (1) the simultaneous presence of large SRA+ cells and an SRA index >30 appear to play a central role in the development of secondary MODS, and could be a useful predictor of poor prognosis in patients with SIRS or MODS; (2) the essential histopathological lesion associated with secondary MODS pathogenesis is systemic capillary injury; and (3) the PB, lung and heart findings mentioned above are characteristic morphological findings suggestive of secondary MODS; (4) a possible mechanism for the development of secondary MODS was proposed.