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Amniotic Fluid Embolism: Anaphylactic Reactions With Idiosyncratic Adverse Response
1Professor, Department of Obstetrics and Gynecology, Nara Medical University, Nara, Japan.
Obstetrical & Gynecological Survey
|August 29, 2015
Summary
Amniotic fluid embolism (AFE) is a rare obstetric emergency with two main mechanisms: cardiopulmonary collapse due to fetal antigen dose-dependent reactions and anaphylactoid reactions involving complement activation and mast cells.
Area of Science:
- Obstetrics
- Immunology
- Pathophysiology
Background:
- Amniotic fluid embolism (AFE) is a rare, severe, and potentially lethal obstetric emergency.
- It can occur during labor or the early postpartum period in previously healthy women.
Purpose of the Study:
- To investigate the pathophysiology of amniotic fluid embolism (AFE).
Main Methods:
- Literature search of English-language studies from 1966-2014.
- Utilized MEDLINE (PubMed) with keywords: amniotic fluid embolism, anaphylaxis, anaphylactoid, complement activation, mast cells, fetal antigens, idiosyncratic.
Main Results:
- AFE involves at least two mechanisms: a mechanical obstruction subtype with sudden cardiopulmonary collapse (fetal antigen dose-dependent) and anaphylactic/anaphylactoid reactions (fetal antigen dose-independent).
- Anaphylactoid reactions are linked to complement activation, postpartum hemorrhage, and involve cardiac mast cells, with both IgE-dependent and IgE-independent pathways.
Conclusions:
- Recent immunologic studies offer a novel perspective on AFE pathophysiology.
- Understanding these immunologic pathways is crucial for advancing AFE research and management.
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