Study of the diagnostic value of iron in fresh water drowning.

The aim of our study was to test the diagnostic value of iron (Fe) in fresh water drowning by investigating the postmortem levels of hemodilution in drowning cases compared to control cases. Twenty-six typical fresh water drowning cases were selected from 128 immersion cases autopsied in our Department of Forensic Pathology between 1998 and 2004. The exclusion criteria were a long postmortem interval and other causes of death than drowning. For all selected cases, the diagnosis of drowning was based on the presence of autopsy findings and positive diatom test. A control population of 12 cases was also selected. For each drowning and control case, iron blood levels were measured in the left ventricle (LV) and right ventricle (RV) of the heart. The mean difference of iron concentration (RVFe-LVFe) between the drowning group and the control group was statistically compared. Furthermore, iron measurements were performed in 19 drowning cases showing advanced putrefaction. The mean difference of iron concentration was significantly higher in the drowning cases compared with controls (P<0.001). All drowning cases showed hemodilution. No overlap was found in the RVFe-LVFe levels between the two groups. Resuscitation attempts seemed to have no effect on the results. In cases of drowning showing advanced putrefaction, the iron test was not reliable because biochemical iron measurement was often prevented by no sufficient blood in the heart or postmortem clots. In conclusion, according to our results, iron seems to be a good biochemical marker in fresh water drowning with a short postmortem interval.