Determination of haemoglobin A1c levels using high-performance liquid chromatography of bloodstains

Abstract

This study aimed to determine haemoglobin A1c (HbA1c) levels in bloodstains shed on glass and fabric surfaces on specified test dates. Blood samples were taken from 26 patients (13 diabetic and 13 non-diabetic). Initial HbA1c levels were detected by using high-performance liquid chromatography (HPLC), and bloodstains were created on both cotton fabric and glass surfaces. Samples were processed at different ages (0, 7, 14, 28 and 56 days) by diluting distilled water and then measuring HbA1c levels by HPLC again. In all stains, HbA1c levels could be determined by using HPLC, but there was a moderate rise in accordance with the age of the stains. A statistically significant difference was found for bloodstains on clothes compared to those on glass surfaces. Receiver operating curve analysis found a sensitivity of 1.0 and specificity of 0.923 (cut-off 6.55) for glass surfaces on the seventh day; a sensitivity of 1.0, a specificity of 0.846 (cut-off 6.45) for clothes on the seventh day; a sensitivity of 1.0 and a specificity of 0.923 (cut-off 6.85) for clothes on the 56th day; and a sensitivity of 1.0 and a specificity of 0.846 (cut-off 7.55) for glass surfaces on the 56th day. In conclusion, this study found that HbA1c levels could be measured with high reliability from forensic bloodstains by using HPLC. Thus, in cases where DNA data banks cannot identify individuals, it would make sense to turn to those who have a medical history of diabetes among the suspects with the results of high HbA1c levels.