Immune system disorders in the early post-injury period in patients after severe brain injury from the perspective of the severity of the injury.

Background: Brain injuries are the most common cause of death in productive age. Besides the extent of the injury, other systemic factors can also affect the outcome. Patients suffering from severe brain injury often experience extracranial inflammatory complications during the early period of treatment. Here, we investigate the changes in immunity in patients with brain injury.

Methods: 121 patients and 92 healthy controls were included in the research. Blood samples were collected on admission and analyzed by flow cytometry and biochemical methods. Multiple clusters of differentiation (CD) and antibody levels were investigated. The results were compared between patients and controls. In addition, results of two classes of severity (Glasgow Coma Scale, GCS, of 3-5 vs. 6-8) were also compared.

Results: Parameters of humoral immunity in patients immediately after admission were significantly lower than those from healthy donors, with the exception of IgE elevated as much as to resemble allergic reaction (p < 0.01). Of cellular parameters, only natural killer (NK) cluster CD56 + was elevated (p < 0.01). Extracranial infectious complications were more common in patients with GCS 3-5.

Conclusions: Strong immune system disorders were observed in patients after severe brain injury, which may contribute to the worse outcome in such patients.