Amniotic Fluid Embolism (AFE): A Review of the Literature Orientated on Two Clinical Presentations—Typical and Atypical

Abstract

Background/Aim: Recently, a comparative study on the incidence of AFE has highlighted rather confusing results, showing that the complication is more than three times higher in North America than that in some European countries. In this paper, we put forward the hypothesis that this discrepancy is due to inaccurate diagnosis of non-classical form of AFE (atypical AFE). We also provide an outline of symptoms that characterize this type of AFE based on the analysis of all available case reports. Material and Methods: We searched Medline from 1969 (its inception) to 2011, using the key words "amniotic fluid embolism". The search produced 1127 articles, including 208 case reports of AFE and other publications identified as eligible for our study (11 review articles and 6 population-based studies of the last few years). Moreover, we looked through the articles from the period before "inception of Medline" to find 178 earlier case reports. Full texts were analyzed. Results and Conclusions: (i) Worldwide, 447 cases of AFE have been reported, including 70 cases of atypical AFE (15.7%). (ii) Typical AFE is characterized by three clinical phases (cardiopulmonary collapse, clotting disorders and hemorrhages, multiorgan disturbances), whereas the atypical one shows lack of cardiopulmonary collapse as the initial presentation-the first to appear is obstetric hemorrhage and/or pulmonary and renal dysfunction. (iii) Four subclasses of atypical AFE were distinguished on the basis of case reports: uterine hemorrhage-type of AFE, ARDS as the only presentation of atypical AFE, paradoxical AFE, and cesarean sectionrelated atypical AFEs.

Amniotic Fluid Embolism- Presenting as Generalised Erythema and Rashes (Possibility of Anaphylactoid Reaction Secondary to Amniotic Fluid Embolism)

“…Clinical Presentation can be Typical or Atypical [1] Typical or classical form of amniotic fluid embolism is seen in This patient has been administered with no other drugs other than saline infusion into uterine cavity. Also, this patient had no history of allergy to oxytocin.…”

The Anaphylactoid Syndrome of Pregnancy: Two Autopsy Cases

“…In the first case, according to the provided blood test results, there were no signs of anemia during resuscitation, ruling out the hemorrhagic shock as the cause of cardiopulmonary arrest. In the atypical form of ASP, like the second case, cardiopulmonary collapse does not occur, and the initial symptom is a life-threatening hemorrhage due to the DIC appearance [14]. Since squamous cells, trophoblasts, and other fetal debris can be found in the central circulation of women with conditions other than ASP uterine atony associated with DIC should always be included in the differential diagnosis of similar cases [15].…”

Atypical presentation of amniotic fluid embolism in liver and colon

“…However, AFE can show very variable atypical forms, whose symptoms and signs differ depending on the concerned viscera and degree of involvement [5]. The diagnosis of such forms is often underestimated [5].…”

“…AFE diagnosis has clinical nature and it depends on the presence of the above clinical signs and of the exclusion of similar pathological conditions [3,4]. However, AFE can arise in atypical forms, which are often difficult to diagnose, and were classified into four sub-groups, although many cases escape an accurate locationing [5].…”

“…A thorough assessment of the latest recommendations by Society for Maternal-Fetal Medicine (SMFM) and Amniotic Fluid Embolism Foundation (AFE Foundation) [3], in addition to the evidence-based reviews [5] and findings in our clinical case could lead to important statements: (1) AFE is a serious clinical syndrome that does not always occur with symptoms and signs which are typical of cardiovascular collapse; (2) AFE may affect any viscera, hollow or parenchymatous, individually and without cardiorespiratory involvement; (3) uncommon presentation arises in different ways according to the involved viscera and the degree of involvement; and (4) so, many AFE cases might escape the clinical diagnosis, due to missing classic triad.…”