Amniotic components in the uterine vasculature and their role in amniotic fluid embolism.

AIM: To evaluate whether the presence of amniotic components in the maternal uterine vasculature could be a specific pathological indicator for amniotic fluid embolism (AFE).

METHODS

Medical records of patients treated between January 2006 and March 2013 were retrospectively examined to identify patients who underwent post-partum hysterectomy or autopsy due to maternal death. Three subjects with AFE with disseminated intravascular coagulation (DIC)-type post-partum hemorrhage (PPH), and 13 non-AFE subjects were included in analysis. Histochemical staining using hematoxylin-eosin (HE) and alcian blue, and immunohistochemical staining for sialyl-Tn were conducted to detect amniotic components in the maternal uterine vasculature.

RESULTS

Alcian blue was positive for amniotic components in the uterine vasculature of all subjects with AFE and of several subjects without AFE. Similarly, HE and sialyl-Tn were negative in some AFE subjects and positive in some non-AFE subjects.

CONCLUSIONS

The presence of maternal intravascular fetal material is not a specific indicator for AFE with DIC-type PPH. Therefore, the presence of fetal components in the uterine vasculature is unlikely to be a definitive indicator for AFE.