# Characteristics of the Cerebrospinal Fluid in Septic Patients with Critical Illness Polyneuropathy - A Retrospective Cohort Study

## TL;DR

This study found that higher levels of certain proteins and immune markers in cerebrospinal fluid may indicate critical illness polyneuropathy in septic patients.

## Contribution

Identified specific cerebrospinal fluid biomarkers associated with critical illness polyneuropathy in septic patients.

## Key findings

- CIP patients had higher 28-day mortality compared to non-CIP patients.
- Levels of protein, WBC, IL-1, IL-6, IL-8, and TNFα were significantly higher in CIP patients.
- IL-1, WBC, and TNFα showed good diagnostic value for CIP with AUC > 0.8.

## Abstract

Critical illness polyneuropathy (CIP) is a complex disease commonly occurring in septic patients which indicates a worse prognosis. Herein, we investigated the characteristics of cerebrospinal fluid (CSF) in septic patients with CIP.

This retrospective study was conducted between Match 1, 2018, and July 1, 2022. Patients with sepsis who underwent a CSF examination and nerve electrophysiology were included. The levels of protein, glucose, lipopolysaccharide, white blood cell (WBC), interleukin (IL)-1, IL-6, IL-8, and tumor necrosis factor (TNF) α in CSF were measured. The fungi and bacteria in CSF were also assessed.

Among the 175 septic patients, 116 (66.3%) patients were diagnosed with CIP. 28-day Mortality in CIP patients was higher than that in non-CIP patients (25.0% vs. 10.2%, P = 0.02) which was confirmed by survival analysis. The results of propensity score matching analysis (PSMA) indicated a significant difference in the level of protein, WBC, IL-1, IL-6, IL-8, and TNFα present in the CSF between CIP patients and non-CIP patients. The results of the receiver operating characteristic (ROC) analysis showed that IL-1, WBC, TNFα, and their combined indicator had a good diagnostic value with an AUC > 0.8.

The increase in the levels of WBC, IL-1, and TNFα in CSF might be an indicator of CIP in septic patients.