Prenatal detection of esophageal atresia: A systematic review and meta-analysis.

INTRODUCTION: The primary aim of this systematic review was to quantify the diagnostic performance of ultrasound, magnetic resonance imaging and amniotic fluid analysis in detecting esophageal atresia prenatally. The secondary aim was to explore the accuracy of individual imaging signs in identifying this anomaly. MATERIAL AND METHODS: MEDLINE, Embase and Cochrane databases were searched. The quality of studies was assessed using the revised tool for the quality assessment of diagnostic accuracy studies. Summary estimates of sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio for the predictive accuracy of ultrasound, magnetic resonance imaging and amniotic fluid analysis in detecting esophageal atresia were computed using the hierarchical summary receiver operating characteristic or DerSimonian-Laird random-effect model, according to the number of studies included in each analysis. PROSPERO registration number: CRD42017055828. RESULTS: Twenty studies (73 246 fetuses, 1760 affected by esophageal atresia) were included. Overall, prenatal ultrasound had a sensitivity of 31.7%. Only two studies reported all data for diagnostic accuracy; based on these studies, prenatal ultrasound had a sensitivity of 41.9%, a specificity of 99.9%, a positive likelihood ratio of 88.1, a negative likelihood ratio of 0.58 and a diagnostic odds ratio of 153.7. Prenatal ultrasound correctly identified 77.9% of cases with esophageal atresia and 21.9% esophageal atresia with an associated tracheo-esophageal fistula. Polyhydramnios was present in 56.3% of cases affected by esophageal atresia, and a small or absent stomach was identified in 50.0% cases. When performed following a suspicious ultrasound, fetal magnetic resonance imaging had an good overall diagnostic accuracy for esophageal atresia, with a sensitivity of 94.7%, a specificity of 89.3%, a positive likelihood ratio of 8.8, a negative likelihood ratio of 0.06 and a diagnostic odds ratio of 149.3. Finally, amniotic fluid analysis with an esophageal atresia index ≥3 had a sensitivity of 89.9% and a specificity of 99.6% in detecting esophageal atresia. CONCLUSIONS: Ultrasound alone is a poor diagnostic tool for identifying esophageal atresia prenatally, and has a high rate of false positive diagnoses. Magnetic resonance imaging and amniotic fluid analysis have high diagnostic accuracy for esophageal atresia. We would recommend their use following a suspicious ultrasound.

The value of amniotic fluid analysis in patients with suspected clinical chorioamnionitis.

Objective To assess the value of incorporating amniotic fluid (AF) analysis in the management of patients with clinical chorioamnionitis. Methods This was a retrospective cohort study of all women carrying a singleton fetus and managed at our center between 2000 and 2009. We included only those women suspected of chorioamnionitis based on one or more of the following: (1) uterine tenderness, (2) maternal fever, (3) maternal and/or fetal tachycardia and (4) purulent discharge. The management was deemed to be justified if (1) pregnancy was terminated <24 weeks and histology confirmed chorioamnionitis; (2) delivery was performed expeditiously after initial assessment and histology confirmed chorioamnionitis; (3) delivery was delayed for 2-7 days and the patient completed a course of antenatal steroids before 34 weeks; and (4) delivery was delayed ≥7 days and histology was not indicative of chorioamnionitis, or delivery occurred after 37 weeks. Univariate and logistic regression analyses were used as appropriate. Results Of the 77 women with suspected chorioamnionitis, AF analysis was performed in 43 (55.8%) cases, and the management was justified in 63 (81.8%) cases based on the aforementioned criteria. Stepwise regression analysis confirmed AF analysis as a predictor of justified management. The rates of composite morbidity, neonatal sepsis, neonatal death and admissions to neonatal intensive care unit were lower in the justified management group. Conclusion Incorporation of AF analysis into clinical assessment does improve the management of suspected chorioamnionitis.

Patients with acute cervical insufficiency without intra-amniotic infection/inflammation treated with cerclage have a good prognosis.

Background The frequency of intra-amniotic infection/inflammation (IAI/I) in patients with midtrimester cervical insufficiency is up to 50%. Our purpose was to determine the perinatal outcomes of cervical cerclage in patients with acute cervical insufficiency with bulging membranes, and to compare the admission-to-delivery interval and pregnancy outcomes according to the results of amniotic fluid (AF) analysis and cerclage placement. Methods This was a retrospective cohort study including singleton pregnancies with cervical insufficiency between 15 and 26.9 weeks in two tertiary health centers. IAI/I was defined when at least one of the following criteria was present in AF: (a) a white blood cell (WBC) count >50 cells/mm3; (b) glucose concentration <14 mg/dL; and/or (c) a Gram stain positive for bacteria. Three different groups were compared: (1) absence of IAI/I with placement of a cerclage; (2) amniocentesis not performed with placement of a cerclage; and (3) IAI/I with or without a cerclage. Results Seventy patients underwent an amniocentesis to rule out IAI/I. The prevalence of IAI/I was 19%. Forty-seven patients underwent a cerclage. Patients with a cerclage had a longer median admission-to-delivery interval (33 vs. 2 days; P < 0.001) and delivered at a higher median gestational age (27.4 vs. 22.6 weeks; P = 0.001) than those without a cerclage. The neonatal survival rate in the cerclage group was 62% vs. 23% in those without a cerclage (P = 0.01). Patients without IAI/I who underwent a cerclage had a longer median admission-to-delivery interval (43 vs. 1 day; P < 0.001), delivered at a higher median gestational age (28 vs. 22.1 weeks; P = 0.001) and had a higher neonatal survival rate (67% vs. 8%; P < 0.001) than those with IAI/I. Conclusion The pregnancy outcomes of patients with midtrimester cervical insufficiency and bulging membranes are poor as they have a high prevalence of IAI/I. Therefore, a pre-operative amniocentesis is key to identify the best candidates for the subsequent placement of a cerclage.

Prediction of neonatal respiratory morbidity by quantitative ultrasound lung texture analysis: a multicenter study.

BACKGROUND: Prediction of neonatal respiratory morbidity may be useful to plan delivery in complicated pregnancies. The limited predictive performance of the current diagnostic tests together with the risks of an invasive procedure restricts the use of fetal lung maturity assessment. OBJECTIVE: The objective of the study was to evaluate the performance of quantitative ultrasound texture analysis of the fetal lung (quantusFLM) to predict neonatal respiratory morbidity in preterm and early-term (<39.0 weeks) deliveries. STUDY DESIGN: This was a prospective multicenter study conducted in 20 centers worldwide. Fetal lung ultrasound images were obtained at 25.0-38.6 weeks of gestation within 48 hours of delivery, stored in Digital Imaging and Communication in Medicine format, and analyzed with quantusFLM. Physicians were blinded to the analysis. At delivery, perinatal outcomes and the occurrence of neonatal respiratory morbidity, defined as either respiratory distress syndrome or transient tachypnea of the newborn, were registered. The performance of the ultrasound texture analysis test to predict neonatal respiratory morbidity was evaluated. RESULTS: A total of 883 images were collected, but 17.3% were discarded because of poor image quality or exclusion criteria, leaving 730 observations for the final analysis. The prevalence of neonatal respiratory morbidity was 13.8% (101 of 730). The quantusFLM predicted neonatal respiratory morbidity with a sensitivity, specificity, positive and negative predictive values of 74.3% (75 of 101), 88.6% (557 of 629), 51.0% (75 of 147), and 95.5% (557 of 583), respectively. Accuracy was 86.5% (632 of 730) and positive and negative likelihood ratios were 6.5 and 0.3, respectively. CONCLUSION: The quantusFLM predicted neonatal respiratory morbidity with an accuracy similar to that previously reported for other tests with the advantage of being a noninvasive technique.

Testing for Zika virus infection in pregnancy: key concepts to deal with an emerging epidemic.

Zika virus is an emerging mosquito-borne (Aedes genus) arbovirus of the Flaviviridae family. Following epidemics in Micronesia and French Polynesia during the past decade, more recent Zika virus infection outbreaks were first reported in South America as early as May 2013 and spread to now 50 countries throughout the Americas. Although no other flavivirus has previously been known to cause major fetal malformations following perinatal infection, reports of a causal link between Zika virus and microcephaly, brain and ocular malformations, and fetal loss emerged from hard-hit regions of Brazil by October 2015. Among the minority of infected women with symptoms, clinical manifestations of Zika virus infection may include fever, headache, arthralgia, myalgia, and maculopapular rash; however, only 1 of every 4-5 people who are infected have any symptoms. Thus, clinical symptom reporting is an ineffective screening tool for the relative risk assessment of Zika virus infection in the majority of patients. As previously occurred with other largely asymptomatic viral infections posing perinatal transmission risk (such as HIV or cytomegalovirus), we must develop and implement rapid, sensitive, and specific screening and diagnostic testing for both viral detection and estimation of timing of exposure. Unfortunately, despite an unprecedented surge in attempts to rapidly advance perinatal clinical testing for a previously obscure arbovirus, there are several ongoing hindrances to molecular- and sonographic-based screening and diagnosis of congenital Zika virus infection. These include the following: (1) difficulty in estimating the timing of exposure for women living in endemic areas and thus limited interpretability of immunoglobulin M serologies; (2) cross-reaction of immunoglobulin serologies with other endemic flaviruses, such as dengue; (3) persistent viremia and viruria in pregnancy weeks to months after primary exposure; and (4) fetal brain malformations and anomalies preceding the sonographic detection of microcephaly. In this commentary, we discuss screening and diagnostic considerations that are grounded not only in the realities of current obstetrical practice in a largely global population but also in basic immunology and virology. We review recent epidemiological data pertaining to the risk of congenital Zika virus malformations based on trimester of exposure and consider side by side with emerging data demonstrating replication of Zika virus in placental and fetal tissue throughout gestation. We discuss limitations to ultrasound based strategies that rely largely or solely on the detection of microcephaly and provide alternative neurosonographic approaches for the detection of malformations that may precede or occur independent of a small head circumference. This expert review provides information that is of value for the following: (1) obstetrician, maternal-fetal medicine specialist, midwife, patient, and family in cases of suspected Zika virus infection; (2) review of the methodology for laboratory testing to explore the presence of the virus and the immune response; (3) ultrasound-based assessment of the fetus suspected to be exposed to Zika virus with particular emphasis on the central nervous system; and (4) identification of areas ready for development.