Research Reports - Role of early cell-free DNA levels decrease as a predictive marker of fatal outcome after severe traumatic brain injury
Clin Chim Acta. 2012 Dec 24;414:12-7
Macher H, Egea-Guerrero JJ, Revuelto-Rey J, Gordillo-Escobar E,
Enamorado-Enamorado J, Boza A, Rodriguez A, Molinero P, Guerrero JM, Dominguez-Roldán JM, Murillo-Cabezas F, Rubio A
INTRODUCTION: Circulating cell-free DNA levels are increased after trauma injury.
This increase is higher since the first hours after trauma and may be related
with primary outcome. A sensitive and reliable biomarker for patients at higher
risk is needed to identify these patients to initiate early intervention. In this
way, circulating DNA may be a possible biological marker after severe TBI.
MATERIALS AND METHODS: We investigated DNA plasma concentrations after severe
traumatic brain injury and during the next 96h in the Intensive Care Unit (ICU)
by real time PCR. 65 patients suffering severe TBI were included in the study.
RESULTS: Cell-free DNA levels were considerably higher in patients samples
compared with voluntary control ones. After the following four days we observed a
51% decrease during the first 24h and a 71% fall from 48h. TBI population was
stratified for the primary outcome (survivors/non-survivor) and DNA levels
decrease ratio was calculated for the first 48h. A higher decrease in the
survivors from 0h to 24h compared with the non-survivors was found. A cut-off
point of 1.95 ratio was established for the detection of the highest proportions
of patients after the TBI that will not survive after the injury with a
sensitivity of 70% and specificity of 66%.
CONCLUSIONS: In summary we showed that severe TBI is associated with elevated
cf-DNA levels and we propose that cf-DNA decrease during the first 24h may
predict patient outcome.