Postmortem methemoglobin concentrations and their significance.

Small concentrations of methemoglobin are present in the blood of normal individuals. Increased concentrations of methemoglobin can be formed by the action of certain chemicals or drugs, or in individuals with specific genetic defects. There is little information available concerning the validity of postmortem methemoglobin concentration as an indicator of antemortem methemoglobinemia. We measured blood concentrations of methemoglobin in 49 autopsy specimens. We conclude that postmortem methemoglobin concentrations are not valid indicators of antemortem methemoglobinemia.