Amniotic Fluid Embolism: a comparison of two classification systems in a retrospective 8-year analysis from two tertiary hospitals

OBJECTIVE

Amniotic fluid embolism (AFE) is a rare life-threatening complication in obstetrics, but the diagnosis lacks a consensual definition. The objective of this study was to compare two different AFE classification systems by analysing the AFE cases from two university hospitals.

MATERIAL AND METHODS

In this retrospective study, all patients with a strong suspicion of AFE between 2014 and 2021 at two university hospitals, LMU Women's University Hospital Munich, and Women's University Hospital Basel, were included. Patient records were checked for the ICD-10 code O88.1 (AFE). Diagnoses were confirmed through clinical findings and/or autopsy. The presence of the diagnostic criteria of the Society of Maternal Fetal Medicine (SMFM) and the AFE Foundation (AFEF) and of a new framework by Ponzio-Klijanienko et al. from Paris, France, were checked and compared using Chi-square-test.

RESULTS

Within our study period, 38,934 women delivered in the two hospitals. Six patients had a strong suspicion of AFE (0.015%). Only three of six patients (50%) presented with all the four diagnostic criteria of the SMFM/AFEF framework. All six patients met the criteria of the modified "Paris AFE framework".

CONCLUSION

Using the "Paris AFE framework" based exclusively on clinical criteria can help clinicians to diagnose AFE, anticipate the life-threatening condition of the patient and prepare immediately for best clinical care.

Maternal Plasma and Amniotic Fluid LBP, Pentraxin 3, Resistin, and IGFBP-3: Biomarkers of Microbial Invasion of Amniotic Cavity and/or Intra-amniotic Inflammation in Women with Preterm Premature Rupture of Membranes

BACKGROUND

We sought to determine whether lipopolysaccharide binding protein (LBP), pentraxin 3, resistin, and insulin-like growth factor binding protein (IGFBP)-3 in plasma and amniotic fluid (AF) can predict microbial invasion of the amniotic cavity (MIAC), intra-amniotic inflammation (IAI), and microbial-associated IAI in women with preterm premature rupture of membranes (PPROM).

METHODS

This was a retrospective cohort study involving 168 singleton pregnant women with PPROM. AF obtained via amniocentesis was cultured and assayed for interleukin (IL)-6 to define IAI and for IL-8 to compare with AF biomarkers. Plasma samples were collected at the time of amniocentesis, and C-reactive protein (CRP) levels in serum were compared with plasma biomarkers. The stored plasma and AF samples were assayed for LBP, pentraxin 3 (PTX3), resistin, and IGFBP-3 by ELISA.

RESULTS

Multivariate logistic regression analysis revealed that: 1) elevated plasma and AF levels of LBP were independently associated with increased risks of MIAC, IAI, and microbial-associated IAI; 2) elevated AF, but not plasma, PTX3, and resistin levels were independently associated with increased risks of MIAC, IAI, and microbial-associated IAI; 3) decreased IGFBP-3 levels in the plasma were independently associated with only IAI, whereas those in the AF were associated with only microbial-associated IAI. Among the tested biomarkers, AF PTX3 and resistin had the highest predictive performance for MIAC, IAI, and microbial-associated IAI (area under the curves [AUC] = 0.85-0.95), which is similar to the performance of AF IL-8. The AUCs of the plasma LBP and IGFBP-3 were similar to that of serum CRP with respect to IAI.

CONCLUSION

Maternal plasma LBP and IGFBP-3 are potential biomarkers for the non-invasive identification of IAI in women with PPROM, with a similar accuracy to the serum CRP level. AF LBP, PTX3, resistin, and IGFBP-3 may be involved in the intra-amniotic inflammatory responses in PPROM complicated by MIAC.

The Amniotic Fluid Proteome Differs Significantly between Donor and Recipient Fetuses in Pregnancies Complicated by Twin-to-Twin Transfusion Syndrome

BACKGROUND

Twin-to-twin transfusion syndrome (TTTS) is a serious complication of monochorionic twin pregnancies. It results from disproportionate blood supply to each fetus caused by abnormal vascular anastomosis within the placenta. Amniotic fluid (AF) is an indicator reflecting the various conditions of the fetus, and an imbalance in AF volume is essential for the antenatal diagnosis of TTTS by ultrasound. In this study, two different mass spectrometry quantitative approaches were performed to identify differentially expressed proteins (DEPs) within matched pairs of AF samples.

METHODS

We characterized the AF proteome in pooled AF samples collected from donor and recipient twin pairs (n = 5 each) with TTTS by a global proteomics profiling approach and then preformed the statistical analysis to determine the DEPs between the two groups. Next, we carried out a targeted proteomic approach (multiple reaction monitoring) with DEPs to achieve high-confident TTTS-associated AF proteins.

RESULTS

A total of 103 AF proteins that were significantly altered in their abundances between donor and recipient fetuses. The majority of upregulated proteins identified in the recipient twins (including carbonic anhydrase 1, fibrinogen alpha chain, aminopeptidase N, alpha-fetoprotein, fibrinogen gamma chain, and basement membrane-specific heparan sulfate proteoglycan core protein) have been associated with cardiac or dermatologic disease, which is often seen in recipient twins as a result of volume overload. In contrast, proteins significantly upregulated in AF collected from donor twins (including IgGFc-binding protein, apolipoprotein C-I, complement C1q subcomponent subunit B, apolipoprotein C-III, apolipoprotein A-II, decorin, alpha-2-macroglobulin, apolipoprotein A-I, and fibronectin) were those previously shown to be associated with inflammation, ischemic cardiovascular complications or renal disease.

CONCLUSION

In this study, we identified proteomic biomarkers in AF collected from donor and recipient twins in pregnancies complicated by TTTS that appear to reflect underlying functional and pathophysiological challenges faced by each of the fetuses.

A Pilot Study of the Short Term Effectiveness and Safety of Amniotic Fluid in Severe Dry Eye Disease

The aim of this study was to evaluate if amniotic fluid (AF) mixed with artificial tears or soaked with a soft contact lens (SCL) as a treatment for severe dry eye disease (DED) would improve its signs or symptoms. In this retrospective pilot study 22 consecutive eyes of 11 patients with level 3 DED classified by DEWS 1 (Dry Eye WorkShop 1 2007), were included in the study between June 1 and September 30 in 2017. The study was conducted before DEWS II (Dry Eye WorkShop II 2017), which was published in October 2017. Therefore, DEWS II was not adopted for this study. Soft Contact Lens Acuvue Oasys of Plano with 8.8 base curve and 14 mm diameters by Johnson and Johnson were used to soak in FloGraft, which is an AF, for 30 minutes before placing in 12 eyes in Group 1. The contact lenses were placed in the left eye for 1 week. In Group 2, 10 eyes used 6 mL of artificial tears mixed with 0.25 mL of AF, which were applied to the eye four times a day for 1 week. No other eye medications were used. The eyes that were included had diffuse punctate staining and fast tear breaking times of <5 seconds with severe ocular symptoms (DEWS 1 level 3-4). Photos of fluorescein stain corneas before the treatment and 1 week after the treatment were used to compare the distribution of punctate staining as the objective outcomes for signs. Several questions adopted from the Ocular Surface disease Index (OSDI) about subjective symptoms before and after the treatment were asked, and documented on the chart. Improvement either in symptoms or signs or both of DED after 1 week at follow-up examination was recorded. Group 1, with SCL 46% had improvement after 1 week and Group 2, with artificial tears 50% had improvement after 1 week. Improvement means either symptom relief or comparatively decreased distribution of punctate staining on the cornea or both. No cases had inflammation, infection, irritation or blurred vision. We concluded that FloGraft as an AF can safely improve the symptoms or the signs of severe DED either as a mix with artificial tears or soaked with SCL by about 50% in this case series without evidence of irritation, inflammation or blurred vision in the short term.

Complement C3a, But Not C5a, Levels in Amniotic Fluid Are Associated with Intra-amniotic Infection and/or Inflammation and Preterm Delivery in Women with Cervical Insufficiency or an Asymptomatic Short Cervix (≤ 25 mm)

BACKGROUND

We aimed to estimate whether elevated levels of complement C3a and C5a in amniotic fluid (AF) are independently associated with increased risks of intra-amniotic infection and/or inflammation (IAI) and spontaneous preterm delivery (SPTD) in women with cervical insufficiency or a short cervix (≤ 25 mm).

METHODS

We conducted a retrospective cohort study of 96 consecutive women with cervical insufficiency (n = 62) or a short cervix (n = 34) at 17 to 27 weeks, and who underwent an amniocentesis. AF was cultured and analyzed for C3a and C5a by enzyme-linked immunosorbent assay kits. The primary outcome measures were IAI (defined as a positive AF culture and/or an elevated AF interleukin-6 level [≥ 7.6 ng/mL]) and SPTD at < 32 weeks.

RESULTS

In multivariable analysis, AF level of C3a was the only variable significantly associated with IAI, whereas C5a level in AF and serum C-reactive protein level were not associated with IAI. Using SPTD at < 32 weeks as the outcome variable in logistic regression, elevated AF levels of C3a were associated with increased risk of SPTD at < 32 weeks after adjusting for other baseline confounders, whereas elevated AF levels of C5a were not.

CONCLUSION

In women with cervical insufficiency or a short cervix, elevated AF level of C3a, but not C5a, is independently associated with increased risks of IAI and SPTD at < 32 weeks. These findings suggest that subclinical IAI or SPTD in the context of cervical insufficiency is related to activation of complement system in AF.

Perinatal outcome after diagnosis of oligohydramnious at term

Background:

Oligohydramnious is threatening condition to fetal health for which some treatment are available and some are under evaluation. Oligohydramnious, is associated with increased pregnancy complication, congenital anomalies and perinatal mortality. There is an inverse relationship between the amniotic fluid index (AFI) and the adverse perinatal outcome. Oligo hydramnlious is clinical condition characteries by amniotic fluid index (AFI) of 5cm or less. Its incidence is 3-5 % of all the pregnancies an accurate and reproducible method of determining abnormality in amniotic fluid volume (AFI) is sonographic asessment of amniotic fluid index (AFI). It often increase the risk of small for gestational age (SGA) and also the incidence of cesarean section, meconium stained, low apgar score and Neonatal intensive care (NICU) admission.

Objectives:

The aim of study was to analyze the fetal out come in low risk pregnant women with oligohydramnious at term. This is a prospective, descriptive study.

Materials and Methods:

The study was conducted at Amiralmomenin hospital in Zabol for a period of 8 months from 2012/Mar/27 to 2012/Nov/5.It included 100 pregnant women diagnosed with the AFI of or less than 5cm at term. Control group included 300 pregnant women with AFI more than 8cm. Comparison was done between the study group and the control group. Regarding the fetal and pregnancy outcome using chi square and p value, detail were recorded in terms of fetal weight, apgar score at 1 and 5 minutes.

Results:

Mode of delivery, NICU admission neonatal death and induction of labour. Oligohydramnious is associated with a high rate of pregnancy complication and increased preinatal morbidity and mortality. Women with oligohydramnious usually have low birth babies.

Conclusions:

However, it can expect a safe and good outcome for which proper fetal surveillance and regular antenatal care visits are required.

Body fluid exosomes promote secretion of inflammatory cytokines in monocytic cells via Toll-like receptor signaling

Tumor-derived exosomes have been shown to induce various immunomodulatory effects. However, the underlying signaling pathways are poorly understood. Here, we analyzed the effects of ex vivo-derived exosomes on monocytic cell differentiation/activation using THP-1 cells as model. We isolated exosomes from various body fluids such as amniotic fluid, liver cirrhosis ascites, and malignant ascites of ovarian cancer patients. We observed that exosomes were internalized by THP-1 cells and induced the production of IL-1β, TNF-α, and IL-6. Analysis of the signaling pathways revealed a fast triggering of NFκB and a delayed activation of STAT3. Pharmacologic and antibody-blocking experiments showed that the initial production of IL-6 was instrumental for subsequent activation of STAT3. Importantly, triggering of cell signaling was not a unique property of tumor exosomes but was also observed with exosomes of noncancerous origin. Exosomal signaling was TLR-dependent as the knockdown of Toll-like receptor 2 (TLR2) and TLR4 blocked NFκB and STAT3 activation. Similar results were obtained with TLR-neutralizing antibodies. Exosomes also triggered the release of cytokines from mouse bone marrow-derived dendritic cells or macrophages. This process was MyD88-dependent, further supporting a role of TLR signaling. Our results suggest that exosomes trigger TLR-dependent signaling pathways in monocytic precursor cells but possibly also in other immune cells. This process could be important for the induction of immunosuppressive mechanisms during cancer progression and inflammatory diseases.

Applying Maternal Serum and Amniotic Fluid CRP Concentrations, and Cervical Length to Predict Preterm Delivery

OBJECTIVE

To investigate the clinical advantage of several prognostic factors for predicting preterm delivery.

MATERIALS AND METHODS

Eighty and six patients with a singleton pregnancy admitted to Vali-Asr hospital underwent genetic amniocentesis between the 15th and 23th weeks were included in this study. Maternal serum C-reactive protein (CRP), transvaginal sonographic measurement of cervical length (CL),were examined on genetic amniocentesis time. Receiver-operating characteristic (ROC) analysis was performed to determine the efficacy of maternal serum and amniotic fluid CRP levels in predicting women with preterm delivery. Correlation between each factor and the duration of pregnancy was investigated.

RESULTS

The prevalence of spontaneous preterm delivery before 37 weeks of gestation was 11%. ROC analysis revealed that maternal serum CRP level was the parameter, which had a significant power in the prediction of preterm delivery. The optimum cut-off level was 1.2 mg/L. The sensitivity and specificity were 95.1% and 91.8%, respectively. The positive predictive value for CL length with the cut off value of 25 mm was 72.1%. No statistically significant difference correlation observed between CL and the duration of pregnancy or amniotic fluid and maternal serum CRP levels.

CONCLUSION

The maternal serum CRP level has a good sensitivity and specificity in the prediction of preterm delivery and this may be helpful in predicting preterm delivery during genetic amniocentesis. Maternal serum CRP measurement is a safe, simple clinically useful, cost effective, non invasive method, that may assist clinicians in evaluation for high-risk patients and determine strategies for the prevention of preterm delivery.

Human amniotic fluid stem cell-derived muscle progenitor cell therapy for stress urinary incontinence

The most promising treatment for stress urinary incontinence can be a cell therapy. We suggest human amniotic fluid stem cells (hAFSCs) as an alternative cell source. We established the optimum in vitro protocol for the differentiation from hAFSCs into muscle progenitors. These progenitors were transplanted into the injured urethral sphincter and their therapeutic effect was analyzed. For the development of an efficient differentiation system in vitro, we examined a commercial medium, co-culture and conditioned medium (CM) systems. After being treated with CM, hAFSCs were effectively developed into a muscle lineage. The progenitors were integrated into the host urethral sphincter and the host cell differentiation was stimulated in vivo. Urodynamic analysis showed significant increase of leak point pressure and closing pressure. Immunohistochemistry revealed the regeneration of circular muscle mass with normal appearance. Molecular analysis observed the expression of a larger number of target markers. In the immunogenicity analysis, the progenitor group had a scant CD8 lymphocyte. In tumorigenicity, the progenitors showed no teratoma formation. These results suggest that hAFSCs can effectively be differentiated into muscle progenitors in CM and that the hAFSC-derived muscle progenitors are an accessible cell source for the regeneration of injured urethral sphincter.

Amniotic fluid stem cells and their application in cell-based tissue regeneration

Advances in stem cell biotechnology hold great promise in the field of tissue engineering and regenerative medicine. Of interest are marrow mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), and induced pluripotent stem cells (iPSCs). In addition, amniotic fluid stem cells (AFSCs) have attracted attention as a viable choice following the search for an alternative stem cell source. Investigators are interested in these cells because they come from the amniotic fluid that is routinely discarded after birth. There have been multiple investigations conducted worldwide in an attempt to better understand AF-SCs in terms of their potential use in regenerative medicine. In this review we give a brief introduction of amniotic fluid followed by a description of the cells present within this fluid. Their history related to stem cell discovery in the amniotic fluid as well as the main characteristics of AF-SCs are discussed. Finally, we elaborate on the potential for these cells to promote regeneration of various tissue defects, including fetal tissue, the nervous system, heart, lungs, kidneys, bones, and cartilage.