Initial results of postmortem diagnosis of diabetes mellitus by Hb A1 determination

Abstract

Ensuring the diagnosis of diabetes mellitus by morphological findings is very difficult. Postmortem determination of blood glucose is of no value because of the influence of glycolysis. In clinical studies, Hb A1 determination is used for long-time therapy control of diabetes. Values of less than 10% Hb A1 show that assimilation of glucose is in order. This study is based on the investigation of blood from 174 cadavers (125 men aged between 17 and 84 years; 49 women aged between 27 and 89 years) with many different causes of death, including some cases of coma diabeticum. Blood was frozen immediately; in 48 cases it was stored at +4 degrees C, too. Besides, we took cerebrospinal fluid and urine from each corpse (frozen at -80 degrees C) for determination of glucose, lactic acid, and acetone. Hemoglobin A1 was analyzed by a chromatographic method: the concentrations of Hb A1 ranged from 7.5% to 20% independent of the actual amount of total hemoglobin in our samples (total Hb from 5 to 32 g/dl). Obviously, there is very little influence of autolysis or prefinal glucose fluctuations in blood on its quantity. There is a positive correlation to the concentration of glucose and lactic acid in cerebrospinal fluid (according to the formula of Traub) and also to the presence of acetone in case of diabetic coma. According to our experience, Hemoglobin A1 is a very useful marker to ensure the diagnosis of diabetes mellitus post mortem. As Hb A1 seems to be very constant and stable vs. autolysis, it may help to clear up cases of unexpected death.