Performance of the neutrophil–lymphocyte ratio as a predictor of severity and mortality in children and adolescents with traumatic brain injury

An inflammatory cascade associated with the systemic neutrophil response can be triggered after traumatic brain injury (TBI), causing neuronal dysfunction, which is considered to be related to the prognosis of the victims. The scope of this research is to identify the performance of the neutrophil–lymphocyte ratio (NLR) as a predictor of prognosis considering TBI severity and death as outcomes in a group of pediatric patients.

We retrospectively evaluated NLR through a consecutive review of the medical records (cross-sectional study) of children and adolescents aged < 17 years victims of TBI. To determine the highest NLR value identified as a predictor, different cutoff points were tested for each outcome. The cutoff points were defined based on the area under curve (AUC) of the receiver operating characteristic (ROC).

Among the 82 children with TBI included in the sample, the performance of AUC-ROC was 0.72 when evaluating NLR as a predictor of TBI severity, with NLR cutoff point of 3, and 0.76 when considering mortality as the outcome, with an increase in the cutoff point to 11.

NLR can be considered a biomarker of brain injury in children and adolescent victims of TBI. Patients with NLR ≥ 3 had a fivefold higher probability of severe TBI and patients with NLR ≥ 11 experienced a ninefold higher risk of death.