Technical note: double immunohistochemical stain (anti-CD31 and anti-cytokeratins) as a tool for a confident forensic post-mortem diagnosis of amniotic fluid embolism.

Amniotic fluid embolism (AFE) is a rare cause of unexpected late maternal gestational death. The forensic post-mortem diagnosis is rendered upon the histological recognition of fetal "foreign" material inside maternal lung vasculature. The authors propose a double immunohistochemical (anti-CD31 plus anti-cytokeratin AE1/AE3) stain in order to assess accurate amniotic fluid pulmonary embolic burden in a highly reproducible fashion based on the fact that such technique allows to detect an impressive amount of scales within lung vasculature, thereby offering further evidence that pulmonary embolic obstructive microangiopathy, rather than anaphylactoid reaction, is major determinant in AFE-related death.