The Clinical Significance of Plasma DNA Quantification for Quake Trauma Patients

Abstract

The aims of this study were to evaluate if the plasma DNA level, which can be an indicator of cell death in vivo, correlates with injury severity in trauma patients and whether its quantification could be used to monitor the efficacy of the treatment of trauma patients. A duplex real-time PCR assay with internal control was developed as a novel method for accurate quantification of plasma DNA and applied to determine the plasma DNA concentrations in a cohort of 1,187 Chinese healthy adults and 283 trauma patients in the deadly China Wenchuan earthquake. Plasma DNA concentrations determined by our newly developed real-time PCR method were not influenced by different DNA extraction protocols, PCR amplification efficiency and sample error. The median plasma DNA concentration of females (16.9 ng/ml) was significantly lower than that of males (22.6 ng/ml) (p < 0.0001). At the 95% confidence interval, the normal reference intervals of plasma DNA concentration were 0~50 ng/ml for males and 0~40 ng/ml for females. During the early stage of injury, the median plasma DNA level of patients was more than 100 ng/ml i.e., five times that of the healthy controls. There was a statistically significant positive correlation between ISS and plasma DNA concentration (R 2= 0.46, p < 0.0001). A statistically significant difference of plasma DNA concentration between patients with and without organ injury was observed (median, 168.9 vs. 96.7, p = 0.001). This newly developed plasma DNA quantification method allows accurate quantitative measurement and can be useful for determining injury severity stratification and disease processes.