Sepsis Associated Encephalopathy (SAE) Biomarkers

Sepsis associated encephalopathy (SAE) is a poorly understood acute cerebral dysfunction that frequently appears in the setting of sepsis induced systemic inflammation. In fact, altered mentation is recognized as an independent predictor of death and poor outcomes in patients with sepsis. SAE may be manifested by a number of symptoms characterized by a change in baseline behavior, attention, alertness, cognition, or executive functioning. It occurs in the absence of direct Central Nervous System (CNS) infection, and the exact pathophysiology is of SAE is unknown, but theoretically seems to encompass a constellation of mechanisms such as impairment of the blood brain barrier (BBB), endothelial dysfunction, alteration in cerebral blood flow and neurotransmission, circulating inflammatory mediators, cellular hypoxia, and metabolic disturbances, that ultimately result in neuronal dysfunction and cell death. SAE is characterized by an altered mental status (AMS) that ranges from delirium to coma, and can lead to long-term cognitive impairment. SAE may appear early in the course of sepsis, and is often underestimated as an independent factor of mortality, yet the pathophysiology of SAE remains unknown, and there is a lack of specific investigations available to clinicians. Studies have evaluated biomarkers as prognostic tools. The Investigator propose to measure neuron specific enolase (NSE), S-100B, glial fibrillary acidic protein (GFAP), ubiquitin C-terminal hydrolase L1 (UCH-L1), Tau protein, Copeptin, spectrin breakdown products (SBDP 145, SBDP150), αII-spectrin N-terminal fragment (SNTF), neurofilament light and heavy chains (NF-L, NF-H), myelin basic protein (MBP), secretoneurin (SN), and other peptide levels in the serum of sepsis patients who develop altered mental status, to evaluate the kinetics of said biomarkers for 72 hours. The Investigator will monitor the course of the patients' hospitalization to determine whether there are biomarker correlates with survi