The archived head-space chromatograms of ethanol determinations in autopsy blood in the years 1996-2003 were analysed. One hundred and two cases with elevated acetone level >250mmol/l were selected in which the biochemical profiles of volatile alcohols (methanol, isopropanol and n-propanol) were determined after "post-hoc" calibration of the constant internal standard. Based on the files obtained from the Prosecutor's Office, the circumstances of death and those preceding death (alcoholism, prolonged or single consumption of alcohol, intoxications with other substances, hypothermia, undernourishment, diabetes) were analysed and the most probable cause of endogenous or exogenous ketonaemia were determined. All cases of unexplained deaths in alcoholics with the ethanol concentration <0.4g/l occurred after withdrawal of long-term consumption of alcohol while all alcoholics with the ethanol concentration >0.4g/l died during the so-called drinking bout. In the group of hypothermia-related deaths with ethanol concentrations <0.4g/l, the acetone concentration was statistically significantly higher than that in hypothermia group with ethanol concentration >0.4g/l in which "congeneric" concentrations of methanol and isopropanol were additionally observed. Furthermore, an algorithm of further diagnostic management was suggested to distinguish the most likely origin of acetonaemia, i.e. accumulation of exogenous "denaturants" of alcohol consumed and cases of endogenous ketogenesis.