Sepsis-associated encephalopathy: From pathogenesis to neuroimaging findings

Sepsis-associated encephalopathy (SAE) is a serious complication of sepsis, which is caused by a dysregulated host response to infection. The high morbidity and mortality of SAE severely diminish the quality of life of the affected patients and families, and therefore, early diagnosis and treatment are essential. The pathogenesis of SAE is complex, involving neuroinflammation, impairment of blood–brain barrier function, neurotransmitter imbalance, and mitochondrial dysfunction. Imaging studies have provided insight into the neuropathological changes by traditional computed tomography and magnetic resonance scans, which reveal changes in brain structure and function in patients with advanced SAE. Currently, SAE is mainly diagnosed by the presence of typical clinical symptoms and by laboratory examination; however, accurate diagnosis in the early stage of SAE remains difficult. With the development of new imaging technologies, there has been an increase in imaging options for the early identification of SAE as well as for studies into the pathogenesis and pathophysiology of the disease. Here, we review the pathogenesis of SAE and the main neuroimaging findings. Furthermore, we suggest how to use the new imaging techniques for early identification and for research into the pathogenesis of SAE, which may help to enhance diagnosis and improve the prognosis of the disease.