Diatom-Positive Cadaver: Drowning or Homicide?

Medico-legal investigations should be performed on all unnatural (homicide, suicide, or accident), unexpected, and suspicious deaths to evaluate the possibility of homicide and ascertain the exact cause of death. However, in some scenarios, burial takes place before an autopsy can be conducted. In such cases, exhumation is performed, which involves excavating the remains of previously buried or cremated individuals for medico-legal investigations. Although the diatom test is a very useful microbiological approach in concluding death by drowning, its reliability remains controversial. Our study presents the case of a cadaver that was exhumed so that medico-legal investigations could be performed to ascertain the exact cause of death. The cadaver was recovered from water but buried before an autopsy could be performed. Upon exhumation, the greater cornu of hyoid bone was fractured with dislocation of the maxilla and mandible. The femur, sternum and clavicle were sent for diatom testing. The diatoms came out positive in the bones; however, the water sample from the gutter didn't test positive for diatoms. Thus, due to the diatom-negative status of water, diatoms from bones can't be compared with suspected water samples. Since diatoms in bones can arise as a result of contamination too, death cannot be concluded by drowning. Manual strangulation led to the fracture of the hyoid bone. Asphyxia due to throttling was declared the cause of death. Due to the unreliability of the diatom test in certain cases, other tests should be performed in auxiliary to the diatom test to conclude death by drowning.