Outcomes for fetal echogenic bowel during the second trimester ultrasound

Defining an Evaluation Protocol for the Infant with Fetal Echogenic Bowel

OBJECTIVE

 This study aimed to develop an algorithm for pediatricians to use for infants diagnosed with fetal echogenic bowel (FEB) to ensure that each patient is fully evaluated for possible complications while avoiding unnecessary morbidity and mortality and health care-associated costs.

STUDY DESIGN

 This was a prospective cohort of neonates for which a diagnosis of FEB was made during a Level 2 anatomy ultrasound between February 2016 and January 2017. Women diagnosed with FEB were offered perinatal genetic counseling and testing. These women also received increased third trimester fetal surveillance, including daily fetal kick counts, fetal growth scans every 3 to 4 weeks beginning at 28 weeks, and weekly fetal nonstress test (NST) and/or BPP beginning at 32 weeks. After delivery, neonates received a postnatal evaluation including birth weight, gestational age at birth, presence of other abnormalities, and associated perinatal morbidity and mortality. Comparison between findings was performed using chi-square test. All statistical evaluation was performed using SPSS.

RESULTS

 Among 919 pregnant patients who received Level 2 anatomy ultrasounds at a Regional Perinatal Center during the study period, 70 received a diagnosis of FEB. Of those diagnosed with FEB, 52 (74.3%) delivered at the same Regional Medical Center. Of these 52 delivered infants, 3 (5.8%) were intrauterine fetal demises (IUFDs) and 4 (7.6%) had unaffected twins. Only one multifetal gestation had the diagnosis of FEB in both the twins. Only 19 of the infants delivered had a kidney, ureter, and bladder X-ray (KUB) performed secondary to prematurity or abnormal exams.

CONCLUSION

 This study showed that the majority of infants diagnosed with FEB had a normal exam following delivery, and that most of the neonatal outcomes of neonatal intensive care unit admissions and other neonatal complications are a result of prematurity rather than FEB. Although the algorithm did not have significant results, it is easy to follow and implement in larger studies.

KEY POINTS

· Majority of infants with FEB have a normal physical exam after delivery.. · Majority of neonatal outcomes evaluated were a result of prematurity rather than FEB.. · FEB is a soft marker for potential abnormalities and fetal morbidity/mortality..

The Sonographic Features of Malformation in Fetal Echogenic Bowel and Its Relationship With Chromosome Abnormalities

ABSTRACT

The aims of this study were to analyze the sonographic features and clinical prognosis of fetal echogenic bowel (FEB) and to evaluate the value of FEB in the prediction of fetal chromosomal abnormalities. Eight hundred eighty-two fetuses with FEB were selected. The ultrasonographic features and the chromosomal examination were retrospectively analyzed. Among the 882 FEB, 272 (30.8%) cases had malformation. The most common malformation was cardiovascular malformation (21.6%), followed by urinary malformation (9.0%), craniocerebral malformation (6.8%), and gastrointestinal malformations (5.6%). According to other combined ultrasound abnormalities, the FEBs were divided into 4 groups: isolated FEB group (490 cases), ultrasound soft indicators group (130 cases), single malformation group (117 cases), and multiple malformation group (145 cases). A total of 45 cases (5.1%) were detected with chromosomal abnormalities. Compared with isolated FEB group, the rate of chromosomal abnormality in other 3 groups was significantly higher. Among 490 cases of isolated FEB, 114 cases of isolated FEB group with adverse pregnancy outcomes were selected as the experimental group, and 376 cases of FEB group with good prognosis were selected as the control group. There were significant differences of the location, shape, intensity, and progression between the 2 groups. Multivariate logistic regression analysis showed that central location and progression of FEB were independent risk predictors of poor prognosis. The combined malformation rate is high for FEB fetuses. The fetal systems should be carefully examined when FEB is found in prenatal ultrasound.

Pathophysiology of Hyperechogenic Bowel in Congenitally Human Cytomegalovirus Infected Fetuses

Hyperechogenic bowel (HB) is a nonspecific ultrasound finding that can be associated with human cytomegalovirus (CMV) congenital infection. In this study, we investigated HB pathophysiology in CMV-infected fetuses. We examined small and large intestine as well as pancreas in 8 fetuses at 22 weeks of gestation with congenital CMV infection. Ultrasound findings showed 4 fetuses with HB and 4 without. As negative group, 4 fetuses without CMV infection and without HB were studied. Immunohistochemistry for CMV, lymphocytic infiltrate, B-cell leukemia/lymphoma-2 (bcl-2), CD-117, cystic fibrosis transmembrane regulator (CFTR) were performed. HB fetuses showed multiple and sequential CMV-positive ganglion cells of Auerbach’s myenteric plexus. In the ganglia, bcl-2 was weakly expressed representing a reduced neuronal functionality. CD-117 revealed a regular distribution of Cajal cells, the pacemakers of intestinal contractility. Pancreas showed normal CFTR staining, indicating a preserved exocrine secretion, thus unlikely a contributory factor in HB. In CMV-infected fetuses without HB, CMV-positive cells were scatteredly found in ganglion cells and bcl-2 was strongly expressed. Intestinal CD-117 and pancreatic CFTR expression were similar to fetuses with HB. In conclusion, fetal CMV infection of the bowel may lead to peristalsis impairment (paralytic ileus) due to intestinal plexus involvement, which at ultrasound appeared as HB.

Incidental Fetal Ultrasound Findings: Interpretation and Management

Ultrasonography is a common component of prenatal care worldwide and is often used in early pregnancy to determine gestational age, number of fetuses, fetal cardiac activity, and placental location. Patients and their families may also consider ultrasonography a social event, as it provides confirmation and reassurance of a normal pregnancy. Ultrasound screening is typically scheduled in the second trimester to visualize fetal anatomy and confirm gestational age. Most ultrasound examinations are reassuring, but some incidentally identify structural anomalies and soft markers for aneuploidy, making it necessary for health care providers to correctly interpret these findings. The health care provider's ability to prepare patients prior to the ultrasound and deliver the necessary information needed to make informed decisions regarding any follow-up screening or diagnostic testing is critical to reducing parental anxiety. Preparation for the anatomic survey should include counseling for normal and abnormal findings. The ethical concepts of patient autonomy and shared decision making are used as a guide in providing this critical information and enabling informed choices during follow-up for incidental ultrasound findings.

Incidence and Carrier Frequency of CFTR Gene Mutations in Pregnancies With Echogenic Bowel in Nova Scotia and Prince Edward Island

OBJECTIVE

Fetal echogenic bowel (echogenic bowel) is associated with cystic fibrosis (CF), with a reported incidence ranging from 1% to 13%. Prenatal testing for CF in the setting of echogenic bowel can be done by screening parental or fetal samples for pathogenic CFTR variants. If only one pathogenic variant is identified, sequencing of the CFTR gene can be undertaken, to identify a second pathogenic variant not covered in the standard screening panel. Full gene sequencing, however, also introduces the potential to identify variants of uncertain significance (VUSs) that can create counselling challenges and cause parental anxiety. To provide accurate counselling for families in the study population, the incidence of CF associated with echogenic bowel and the carrier frequency of CFTR variants were investigated.

METHODS

All pregnancies for which CF testing was undertaken for the indication of echogenic bowel (from Nova Scotia and Prince Edward Island) were identified (January 2007-July 2017). The CFTR screening and sequencing results were reviewed, and fetal outcomes related to CF were assessed.

RESULTS

A total of 463 pregnancies with echogenic bowel were tested. Four were confirmed to be affected with CF, giving an incidence of 0.9% in this cohort. The carrier frequency of CF among all parents in the cohort was 5.0% (1 in 20); however, when excluding parents of affected fetuses, the carrier frequency for the population was estimated at 4.1% (1 in 25). CFTR gene sequencing identified an additional VUS in two samples.

CONCLUSION

The incidence of CF in pregnancies with echogenic bowel in Nova Scotia and Prince Edward Island is 0.9%, with an estimated population carrier frequency of 4.1%. These results provide the basis for improved counselling to assess the risk of CF in the pregnancy, after parental carrier screening, using Bayesian probability. Counselling regarding VUSs should be undertaken before gene sequencing.

Adverse Perinatal Conditions Associated With Prenatally Detected Fetal Echogenic Bowel in Nova Scotia

OBJECTIVE

This study sought to estimate the association of adverse perinatal outcomes with pregnancies complicated by fetal echogenic bowel.

METHODS

Data for pregnancies complicated with echogenic bowel identified in the second trimester were derived from the tertiary referral IWK Health Centre (Halifax, NS) Viewpoint Ultrasound Database augmented by medical chart review. The study was undertaken between 2003 and 2014. Rates of positive cytomegalovirus and toxoplasmosis infection were determined using maternal serology and amniocentesis results. Rates of intrauterine growth restriction, abnormal karyotype, cystic fibrosis, antenatal bleeding, and bowel abnormalities were also determined. Neonatal information included newborn urine culture results and postnatal genetic testing. Univariate analyses compared rates of infection with isolated echogenic bowel and echogenic bowel with other ultrasound findings, with statistical significance set at P <0.05.

RESULTS

There were 422 pregnancies identified prenatally with echogenic bowel (82% had isolated echogenic bowel). Of these, 92 (22%) had at least one of the foregoing associated abnormalities. Three percent of women had serologic test results positive for cytomegalovirus or toxoplasmosis, with <1% documented newborn infections. Cystic fibrosis and other genetic diagnoses were observed in 8%, intrauterine growth restriction in 14%, antenatal bleeding in 19%, and bowel abnormalities in 3% of the cases of echogenic bowel. Pregnancies with isolated echogenic bowel had an 80% reduction in risk for these significant outcomes, in contrast to a four- to 11-fold increased risk of specific outcomes when additional ultrasound findings were present.

CONCLUSION

An overall rate of adverse conditions of 22% with prenatally detected echogenic bowel serves to inform women and health care providers and emphasizes the importance of careful screening fetal ultrasound studies and timely referral for comprehensive assessment with findings of echogenic bowel for evaluation for associated findings.

Congenital cytomegalovirus infection: patterns of fetal brain damage

Cytomegalovirus (CMV) is the most prevalent infectious agent causing neurological dysfunction in the developing brain. This study analysed the different patterns of tissue damage, particularly in the brain, of fetuses with documented CMV infection. We studied 45 fetuses at 20-21 weeks of gestation with congenital CMV infection documented by invasive positive prenatal diagnosis. At the time of amniocentesis, abnormal ultrasound findings had been recorded for 13 of the 45 fetuses (29%). Histological and immunohistochemical characterization was performed on the placenta, brain, heart, lung, liver, kidney, and pancreas. The different degrees of brain damage were correlated with tissue viral load, inflammatory response, placental functionality, and extramedullary haematopoiesis. Even though a high CMV load was detected in all amniotic fluids, brain infection occurred in only 62% of the fetuses and with different degrees of severity. Tissues with a low viral load showed a globally weak inflammatory response, and fetuses had only mild brain damage, whereas tissues with a high CMV load showed prominent infiltration of the activated cytotoxic CD8(+) T-lymphocytes responsible for immune-mediated damage. Furthermore, severe placental infection was associated with diffuse villitis and necrosis, consistent with functional impairment and possible consequent hypoxic cerebral damage. Brain injury induced by CMV congenital infection may be the result of uncontrolled viral replication, immune-mediated damage by cytotoxic CD8(+) T-lymphocytes, and, in the presence of placental insufficiency, fetal hypoxia.

Perinatal outcomes of fetal echogenic bowel

OBJECTIVE

To investigate perinatal outcomes of fetal echogenic bowel (FEB).

METHOD

This is a retrospective observational study of FEB cases from Jan 2005-Dec 2010. Data from ultrasound and fetal medicine investigations, uterine artery Doppler (UAD), intra-partum care and neonatal outcome were obtained from Fetal Medicine, Obstetric and Neonatal Databases.

RESULTS

There were 139 cases presenting at 21(+5) (15(+1) -35(+5) ) weeks gestation. Overall, 106/139 (76.2%) were live born (LB), 8/139 (5.8%) were complicated by intra-uterine deaths (IUD), 11/139 (7.9%) had termination of pregnancy (TOP) and 14/139 (10.1%) were lost to follow-up after 28 weeks gestation. Six had chromosomal/genetic abnormalities, two had congenital cytomegalovirus, none had cystic fibrosis.Uterine artery Doppler was normal in 106/130 (81.5%) cases. In this group, there were no cases of fetal growth restriction (FGR), 95/106 (89.6%) were LB, 1/106 (0.94%) had an IUD. In the abnormal UAD group, 17/24 (70.1%) developed FGR, 11/24 (45.8%) were LB, 4/24 (16.7%) had TOP, 7/24 (29.2%) had IUD.In total, 20/106 (18.9%) live births were admitted for specialist neonatal care, 12/20 (60%) for prematurity. Only one had primary bowel pathology.

CONCLUSION

Pregnancies with FEB and screen positive UAD are at risk of adverse perinatal outcome. Primary bowel pathology is rare following the finding of FEB.

Perinatal outcomes following the ultrasound diagnosis of echogenic bowel: an Australian perspective

INTRODUCTION

The aim of this study was to describe the association between fetal echogenic bowel (FEB) diagnosed during the second trimester and adverse perinatal outcomes in an Australian antenatal population.

METHODS

A retrospective analysis of ultrasound scans was performed between March 1, 2004 and March 1, 2009 at The Royal Women's Hospital, Melbourne, Vic., Australia. Cases reported as having FEB on second trimester ultrasound were included. Medical records of each case were reviewed and information concerning additional investigations and perinatal outcomes were extracted.

RESULTS

A total of 66 cases were identified in our database. Three patients (5%) were excluded from further analysis as they were lost to follow-up, leaving 63 (95%) cases in this series. Thirty-two fetuses (52%) underwent karyotyping via amniocentesis, 5 (16%) of which were found to have chromosomal defects. Maternal serology for cytomegalovirus (CMV) was performed in 49 (78%) cases. Investigations indicated a total of 5 women who had CMV infection during their pregnancy. Thirty-three pregnancies (53%) were tested for cystic fibrosis (CF) and 1 baby was confirmed to have CF postnatally. Among the 50 liveborn infants, 3 cases of fetal growth restriction were apparent. Overall, 42 of the 50 liveborn infants (84%) and 67% of the entire cohort of 63 patients with a midtrimester diagnosis of FEB had a normal short-term neonatal outcome.

CONCLUSION

This study reiterates the increased prevalence of aneuploidy, CMV, CF and fetal growth restriction in pregnancies complicated by the midtrimester sonographic finding of FEB. However, reassuringly, 67% of cases with ultrasound-detected echogenic bowel in the second trimester had a normal short-term neonatal outcome in this multiethnic Australian population.