Changes in C-reactive protein levels over time in high-temperature environments using postmortem blood

C-reactive protein (CRP) is widely used in forensic science to identify inflammatory factors contributing to the cause of death. However, data on CRP changes in blood from cadavers that have decomposed in high-temperature environments are limited, necessitating further research to enhance its forensic utility. This study aimed to investigate the changes in CRP levels in postmortem blood stored in high-temperature conditions to assess the validity and utility of CRP testing in decomposed cadavers. We analyzed changes in CRP levels in 106 autopsy blood samples from XXXX. Among these, 78 cases with elevated serum CRP levels (≥1 mg/dL) were used as the experimental group. Blood samples were stored at -80°C until thawed and analyzed for CRP changes over 0-30 d in a high-temperature (30°C-32°C) environment. Results showed that 78 cases (73.58%) had elevated serum CRP levels postmortem, while 58 cases (74.36%) had elevated CRP levels in thawed frozen whole blood (TFWB) at 0 d. Serum CRP levels decreased to 67.01% of antemortem serum CRP levels, while TFWB CRP levels at 0 d decreased to 42.85%. After adjusting for the average reduction rate, the number of cases with elevated TFWB CRP levels at 0 d increased to 68 (87.18%). No correlation was found between postmortem interval and TFWB CRP levels under high temperatures, supporting the stability and utility of TFWB CRP as a forensic marker for inflammatory conditions in decomposed cadavers. This study highlights the potential of using TFWB CRP levels for accurate postmortem analysis in forensic settings.