Differential diagnosis on discolorations of the skin in a case of suspected positional asphyxia.

A 65-year-old man was found lifeless in his apartment, laying in a peculiar head-down position. His head was on the floor and his neck was over-flexed, with his trunk flexed on his neck. Examination of the body showed intense violet lividity of the head, torso and limbs, according to the position of the body. Moreover, diffuse hemorrhagic spots on the shoulders, upper part of the back and upper arms, along with an intense arch-shaped purple area on the anterior neck were detected at external examination. Suspicions of neck injuries due to strangulation and death due to positional asphyxia arose, but a thorough examination of circumstantial data and autopsy findings enabled a correct identification of cause and manner of death, and excluded strangulation and positional asphyxia as the cause of death. This case raises several issues on differential diagnosis and underlines the importance of a correct combined analysis of the findings provided by on-scene investigation and autopsy.