Early IL-6 Plasma Concentrations Correlate with Severity of Brain Injury and Pneumonia in Brain-Injured Patients

Abstract

The IL-6 plasma level 1 day after the acute event with a cut-off of 100 pg/mL (Immulite) seems to be a predictor for short-term prognosis and infectious complications in brain-injured patients.

Prognostic factors of neuroinflammation and oxidative stress in brain injury patients at Cipto Mangunkusumo Hospital Jakarta

“…In other words, patients with an initial IL-6 level of 100 pg/mL or below had an 11.4-times higher chance of having an initial GCS over 8. This is consistent with the study of Woicienchowxky et al 4 stating that initial IL-6 plasma levels are associated with brain injury severity. The higher the initial IL-6 serum level, the higher the patient's risk of getting impaired consciousness (low GCS score).…”

“…High IL-6 serum level of patients with pure brain injury showed neuroinflammation and damage of the blood brain barrier, which led to the release of IL-6 into systemic blood circulation. 4,15 After surgery, IL-6 serum level had a downward trend. The post-operative IL-6 level was significantly associated with GCS 7 days post-surgery, meaning that surgery may reduce neuroinflammatory processes.…”

“…Secondary brain damage is triggered by post-traumatic hypoxia in brain tissue, which induces a cascade of destructive biochemical reactions on the cellular level, leading to additional mortality of nerve cells. 4,5 This cascade of reactions comprises free radicals release, neuroinflammation and apoptosis, which are considered to worsen the primary brain injury and to influence the outcome of patients. Secondary brain damage as a result of neuroinflammation is due to the release of inflammatory mediators, especially interleukin 6 (IL-6), the primary regulator of neuroinflammatory reactions.…”

“…Secondary brain damage as a result of neuroinflammation is due to the release of inflammatory mediators, especially interleukin 6 (IL-6), the primary regulator of neuroinflammatory reactions. High levels of IL-6 in acute phase of brain injury is allegedly associated with the degree of brain damage, 4,5 including bloodbrain barrier damage, which may lead to brain tissue ischemia. Due to post-brain injury blood-brain barrier damage, it is assumed that IL-6 will be increased in the serum of patients with severe brain injury.…”

Temporal Profile of Cerebrospinal Fluid, Plasma, and Brain Interleukin-6 After Normothermic Fluid-Percussion Brain Injury: Effect of Secondary Hypoxia

“…IL-6 production has also been demonstrated clinically, with ventricular CSF and plasma levels being elevated for days following TBI (McClain et al, 1991;Kossmann et al, 1995Kossmann et al, , 1996Aibiki et al, 1999;Csuka et al, 1999;Volkmar et al, 1999;Schwerdtfeger et al, 2001;Singhal et al, 2002;Winter et al, 2002;Buttram et al, 2007). Recent experimental and clinical studies have reported a positive correlation between IL-6 levels and injury severity and prognosis (Tarkowski et al, 1995;Juttler et al, 2002;Woiciechowsky et al, 2002;Minambres, et al, 2003;Frugier et al, 2010;Leyet et al, 2011).…”