Isolated fetal pyelectasis and chromosomal abnormalities

The likelihood of detecting abnormal karyotypes in fetuses with a single major anomaly or "soft" marker on ultrasonographic scanning

OBJECTIVE

Fetuses with abnormal karyotypes often exhibit distinctive ultrasonographic markers, including major anomalies and "soft" markers, indicating potential chromosomal issues. A crucial consideration arises when a single fetal anomaly is detected, raising the question of whether karyotyping is warranted, given the associated procedural risks. Our objective was to establish correlations between single fetal anomalies identified through ultrasound and chromosomal abnormalities.

METHODS

A cross-sectional study analyzed the karyotype of 1493 fetuses and detected a single ultrasonographic anomaly over a 16-year period. Karyotyping was performed using the standard karyotype technique. Moreover, data regarding the type of anomaly detected ultrasonographically, karyotype results, and outcomes following interventions were collected. Among other methods, the use of positive likelihood ratios (LR+) was used to evaluate the diagnostic accuracy of ultrasound compared to karyotyping.

RESULTS

In total, an aberrant karyotype was identified in 99 fetuses (6.6%). This was most commonly observed in cases involving a "soft" marker, occurring in 27 out of 218 fetuses (12.4%). The most frequently detected aberrant karyotype resulted from aneuploidies (80.6% of cases), notably trisomy 21 (50.5%). "Soft" markers predicted chromosomal issues (LR+ = 1.9; OR = 2.4), and isolated polyhydramnios (LR+ = 1.54; OR = 1.6) showed significance in predicting fetal chromosomal aberrations.

CONCLUSION

When assessing the necessity for karyotyping in fetuses with single major anomalies or "soft" markers, it is crucial to consider individual risks for chromosomopathies, including the LR+ of the detected marker. In cases where fetuses exhibit isolated anomalies with a normal karyotype, additional diagnostic measures, such as molecular cytogenetic and molecular genetics techniques, may become necessary.

State of the Science for Kidney Disorders in Phelan-McDermid Syndrome: UPK3A, FBLN1, WNT7B, and CELSR1 as Candidate Genes

Phelan-McDermid syndrome (PMS) is a neurodevelopmental disorder caused by chromosomal rearrangements affecting the 22q13.3 region or by SHANK3 pathogenic variants. The scientific literature suggests that up to 40% of individuals with PMS have kidney disorders, yet little research has been conducted on the renal system to assess candidate genes attributed to these disorders. Therefore, we first conducted a systematic review of the literature to identify kidney disorders in PMS and then pooled the data to create a cohort of individuals to identify candidate genes for renal disorders in PMS. We found 7 types of renal disorders reported: renal cysts, renal hypoplasia or agenesis, hydronephrosis, vesicoureteral reflux, kidney dysplasia, horseshoe kidneys, and pyelectasis. Association analysis from the pooled data from 152 individuals with PMS across 22 articles identified three genomic regions spanning chromosomal bands 22q13.31, 22q13.32, and 22q13.33, significantly associated with kidney disorders. We propose UPK3A, FBLN1, WNT7B, and CELSR1, located from 4.5 Mb to 5.5 Mb from the telomere, as candidate genes. Our findings support the hypothesis that genes included in this region may play a role in the pathogenesis of kidney disorders in PMS.

Outcome of fetuses with soft markers: results of 3016 cases in Ahvaz city

Background: Although soft markers may be seen as normal variants, they are important due to their association with chromosomal and congenital abnormalities. Methods: This cross-sectional descriptive-analytical study was done on 3016 women who referred for perinatal care. Fetuses with any of soft markers including thickened nuchal fold (TNF), mild pyelectasis (MP), choroid plexus cyst (CPC), single umbilical artery (SUA), mega cisterna magna (MCM) and mild ventriculomegaly (MVM) were followed during pregnancy and birth. Data analysis was carried out using SPSS for Windows (version 22). Data were analyzed using chi-square and T-test. A p-value <0.050 was considered statistically significant. Results: 285 (9.4%) fetuses with soft markers Including 148 (4.9%) fetuses with CPC, 118 (3.9%) fetuses with MP, 2 (0.1%,) fetuses with isolated TNF, 8 (0.3%) fetuses with isolated MVM, 4 (0.13%) fetuses with SUA, 4 (0.13%) fetuses with MCM were identified, and one fetus had TNF and MVM simultaneously. In cases with CPC, no abortion or major structural abnormalities were observed and all 148 neonates had normal phenotypes at birth. Among 118 cases with MP, one case had a major cardiac disorder, and 2 cases of abortions (1.7%) were reported (p=0.481). 83 cases (70.3%) were male and 35 cases (29.7%) were female (p=0.021) and all neonates had a normal phenotype. Both pregnancies with isolated TNF resulted in abortion. Of the 8 cases with isolated MVM, two cases had major structural abnormalities. 2 cases of abortion were reported and all infants had a normal phenotype. In one case, that fetus had TNF and MVM simultaneously. Amniocentesis showed no aneuploidy. No major structural abnormalities were observed in fetuses with SUA. One case of abortion was reported. Among the three births, two pre-term births were reported, and all three infants had normal phenotype. In four cases with MCM, no major structural abnormality was observed and all four neonates had normal phenotype. Conclusion: In cases without association with other structural abnormality, mothers who have fetuses with CPC or MP should be reassured that the pregnancy outcomes are generally favorable.

Antenatal hydronephrosis and fetal urine sampling

The aim of this study is to evaluate the significance of renal pelvis aspiration (RPA) in the management of antenatal hydronephrosis (AHN). This study enrolled 15 AHN cases (one twin pregnancy) that necessitated RPA for AHN. Chromosomal abnormalities, gene disorders, and additional life-threatening congenital abnormalities were eliminated prior to intrauterine interventions. Urine analysis were performed for the evaluation of renal function. Normal renal function was observed in six neonates/infants (40%) (group 1), whereas impaired renal function and various type of urinary system anomalies were observed in 9 neonates/infants (60%) (group 2) during the short-term and longitudinal follow-up periods. There were statistically significant differences in the oligohydroamniosis rate, mean fetal urine sodium value, mean fetal urine β2-microglobulin, mean gestational week at birth, and mean birthweight values between the groups (P = 0.007, P < 0.001, P = 0.035, P < 0.001, and P = 0.001, respectively). Renal pelvis aspiration and urine analysis were substantial for the management of AHN in necessary cases. β2-microglobulin and sodium are clinically useful markers to detect the presence of severe renal damage due to obstructive uropathy and thus, important adjuvants in the proper selection of fetuses for further antenatal interventions.

Postnatal outcomes of babies diagnosed with hydronephrosis in utero in a tertiary care centre in India over half a decade

Background

Prenatal hydronephrosis is defined as the dilatation of the fetal renal pelvis and/or calyces and is the commonest anomaly detected in utero

Methods

This was a retrospective study to look at how well 148 antenatally detected cases of fetal hydronephrosis correlated with postnatal evaluation.

Results

Antenatal hydronephrosis was detected with a prevalence of 0.33%. The mean gestational age at diagnosis was 25.48 [standard deviation (SD) 6.36]. One hundred and sixteen (78.3%) fetuses had serial ultrasound scans during pregnancy to look for the progression of the condition. At the time of diagnosis, 30.1% of the fetuses were diagnosed to have mild hydronephrosis, 43.9% to have moderate hydronephrosis and 25.8% to have severe hydronephrosis. Follow-up ultrasounds during the prenatal period, 65% showed progression of the renal pelvis dilatation, 25.8% showed stable disease and 9.1% showed resolution on their subsequent scan. Almost half (46%) were found to have transient/physiological hydronephrosis. Thirty-one (20.9%) of the babies required an operation. An anteroposterior renal pelvis diameter (APD) of the fetal renal pelvis ≥17.5 mm can predict the need for surgery with a sensitivity of 70% and a specificity of 76.6%.

Conclusion

Counselling and decisions must be based on a series of ultrasound scans rather than a single evaluation. We use a cut-off of 17.5 mm as an indicator of possible postnatal surgical intervention.

A Pediatrician's Take on a Few Common Infant Urologic and Gynecologic Issues

Urologic and gynecologic issues are common in a pediatric primary care office. This article focuses on the evaluation and management of a few common diagnoses in infants and young children: fetal hydronephrosis, labial adhesions, physiologic phimosis, and hydrocele. This article can help pediatricians decide when these common issues can be managed in the primary care office and when they need subspecialty guidance. [Pediatr Ann. 2017;46(11):e397-e399.].

Ultrasound screening: Status of markers and efficacy of screening for structural abnormalities

Aneuploidy is a major cause of perinatal morbidity and mortality and can have a significant impact on expecting parents and their families. With early screening and diagnosis it is important to be able to educate parents regarding the potential impact of the diagnosis. This knowledge allows parents the opportunity to consider management options early in the pregnancy, permitting more time to mentally and emotionally prepare both for the course of the pregnancy, and after the birth of the child should the pregnancy continue. Prenatal screening provides pregnant women a non-invasive risk assessment for the most common aneuploidies. Those who are considered "high-risk" then have the option for additional diagnostic (invasive) testing. Prior to the 1980s, prenatal screening consisted of risk assessment through maternal age; however, with the advent of maternal serum biochemical analysis and ultrasound, the field of prenatal screening developed significantly. As biochemical and sonographic advances continued into the 1990s, the emphasis shifted to risk assessment in the first trimester, with the combination of maternal serum analytes and sonographic evaluation of the nuchal translucency.(1) Within the last decade, the introduction of non-invasive screening (NIPT/S) has shown great impact on the expansion and evolving practice of prenatal screening. Although in many places the standard for prenatal testing continues to include maternal serum analytes and sonographic evaluation, the role of each marker alone and in combination remains important. In the era of increasingly available screening tests, especially with NIPT/(NIPS), this article attempts to review the current role of ultrasound in prenatal care and elucidate the role of ultrasound markers in prenatal screening.

Second trimester ultrasound markers of fetal aneuploidy

Although it is widely accepted that the best time to screen for chromosomal abnormalities is the first trimester, ultrasound evaluation of the fetus in the second trimester has also been shown to be useful for this purpose. A multitude of markers of varying strength has been developed over the past 30 years. In addition, the optimal time to diagnose fetal anomalies with confidence is also the mid second trimester. Therefore, performance of obstetrical ultrasound at this point in gestation continues to be an important component of prenatal care.

Ultrasonographic fetal soft markers in a low-risk population: prevalence, association with trisomies and invasive tests

OBJECTIVE

To investigate the prevalence of soft markers identified at second trimester ultrasound in a low-risk population and the association of these markers with trisomies and invasive testing.

DESIGN

Prospective observational study.

SETTING

Swedish University Hospital.

POPULATION

All women with fetuses examined by ultrasound at 15(+0) -22(+0)  weeks gestation between July 2008 and March 2011.

METHODS

Cases with soft markers were compared with non-cases with regard to trisomies and invasive testing.

MAIN OUTCOME MEASURES

Prevalence of soft markers, likelihood ratio for trisomies and risk ratio for invasive tests after detection of soft markers.

RESULTS

Second trimester ultrasound was performed on 10 710 fetuses. Markers were detected in 5.9% of fetuses. 5.1% were isolated, 0.7% were multiple and 0.1% were combined with an anomaly. Presence of markers showed a positive likelihood ratio for Down syndrome, but the association (likelihood ratio = 7.1) was only statistically significant for the combined category of any marker (isolated, multiple or combined with anomaly). The risk ratio for invasive testing after the second trimester ultrasound was 24.0 in pregnancies with isolated soft markers compared with those without markers.

CONCLUSION

In a low-risk population, soft markers were found in 5.9% of fetuses at second trimester ultrasound. The likelihood ratio for Down syndrome was significant only for any marker (isolated, multiple or combined with anomaly). The presence of soft markers increased the incidence of invasive procedures substantially. Soft markers should be noted when information on second trimester ultrasound is formulated, and all units performing fetal ultrasound examinations should have established routines concerning information management when soft markers are identified.

Isolated fetal pyelectasis and the risk of Down syndrome: a meta-analysis

OBJECTIVES

We performed a meta-analysis to examine the performance of second-trimester (14-24 weeks' gestation) isolated fetal pyelectasis as a marker for trisomy 21 and to calculate its associated weighted pooled likelihood ratios.

METHODS

PubMed, Ovid MEDLINE and Cochrane databases were searched using the terms 'pyelectasis' and 'pelviectasis'. Studies were included if fetuses with isolated pyelectasis were reported separately from fetuses with other soft markers of aneuploidy and/or structural anomalies and if knowledge of the fetal karyotype was unknown at the time of ultrasound examination.

RESULTS

Individual study statistics were pooled as weighted positive and negative likelihood ratios with 95% CIs, using a random-effects model. Ten observational studies were included (2148 cases of isolated pyelectasis). Isolated fetal pyelectasis was defined in seven out of 10 studies as a renal pelvis anteroposterior diameter of ≥ 4 mm. Isolated fetal pyelectasis was associated with pooled positive and negative likelihood ratios of 2.78 (95% CI, 1.75-4.43) and 0.99 (95% CI, 0.98-1.00), respectively.

CONCLUSIONS

The detection of isolated fetal pyelectasis on mid-trimester ultrasound is associated with an increased likelihood of trisomy 21. If the finding of isolated fetal pyelectasis is used to adjust the trisomy 21 risk from maternal serum screening tests, a positive likelihood ratio of 2.78 should be used in the calculation.

Revised guidelines on management of antenatal hydronephrosis

Widespread antenatal screening has resulted in increased detection of anomalies of the kidneys and urinary tract. The present guidelines update the recommendations published in 2000. Antenatal hydronephrosis (ANH) is transient and resolves by the third trimester in almost one-half cases. The presence of oligohydramnios and additional renal or extrarenal anomalies suggests significant pathology. All patients with ANH should undergo postnatal ultrasonography; the intensity of subsequent evaluation depends on anteroposterior diameter (APD) of the renal pelvis and/or Society for Fetal Urology (SFU) grading. Patients with postnatal APD exceeding 10 mm and/or SFU grade 3-4 should be screened for upper or lower urinary tract obstruction and vesicoureteric reflux (VUR). Infants with VUR should receive antibiotic prophylaxis through the first year of life, and their parents counseled regarding the risk of urinary tract infections. The management of patients with pelviureteric junction or vesicoureteric junction obstruction depends on clinical features and results of sequential ultrasonography and radionuclide renography. Surgery is considered in patients with increasing renal pelvic APD and/or an obstructed renogram with differential renal function <35-40% or its subsequent decline. Further studies are necessary to clarify the role of prenatal intervention, frequency of follow-up investigations and indications for surgery in these patients.

Discovery of soft markers on fetal ultrasound: maternal implications

OBJECTIVE

to explore women's experiences of referral to tertiary care on the basis of uncertain ultrasound findings.

DESIGN

a qualitative method using Rice and Ezzy's thematic analysis approach. Data were gathered through two in-depth interviews over a six to eight-month period.

PARTICIPANTS

a total of 20 interviews were conducted among pregnant women, purposively recruited at a tertiary facility. Inclusion criteria were based on detection of an isolated soft marker in an otherwise normal pregnancy.

DATA ANALYSIS

interview data were transcribed and data were subjected to thematic analysis.

FINDINGS

mothers journeyed through a temporal sequence of adjustment following referral to specialist services. Four distinct phases were identified: realisation; making sense of events; anxious waiting; and having no clear resolution.

CONCLUSION

trends of increasing prenatal surveillance together with advancing technology make this study timely and of global interest. Findings suggest that women identified as 'at risk' before being discharged uneventfully may be prone to attachment issues and a host of other difficulties. The complexities inherent in this experience should be of interest to a broad range of health professionals. An appreciation of this experience may assist midwives and other health professionals to provide more meaningful maternal support to women identified as 'at risk'.

Choroid plexus cyst, intracardiac echogenic focus, hyperechogenic bowel and hydronephrosis in screening for trisomy 21 at 11 + 0 to 13 + 6 weeks

OBJECTIVES

To investigate the potential value of choroid plexus cyst, intracardiac echogenic focus, hydronephrosis and hyperechogenic bowel as markers of trisomy 21 at 11 + 0 to 13 + 6 weeks.

METHODS

We examined three-dimensional volumes from 228 fetuses with trisomy 21 and 797 chromosomally normal fetuses at 11 + 0 to 13 + 6 weeks of gestation. We looked for choroid plexus cysts with a minimum diameter of 1.5 mm, intracardiac echogenic focus, hydronephrosis with a minimum anteroposterior diameter of the pelvis of 1.5 mm and hyperechogenic bowel.

RESULTS

The prevalence of intracardiac echogenic focus, hydronephrosis and hyperechogenic bowel was significantly higher in trisomy 21 than in normal fetuses (9.6% vs. 1.5%, 17.1% vs. 5.3% and 11.4% vs. 2.4%, respectively). There was no significant difference between the two groups in the prevalence of choroid plexus cysts (7.5% vs. 5.0%). There were no significant differences in crown-rump length or nuchal translucency thickness in either chromosomally normal or trisomy 21 fetuses between those with and those without any one of the markers.

CONCLUSIONS

At 11 + 0 to 13 + 6 weeks the prevalence of intracardiac echogenic focus, hydronephrosis and hyperechogenic bowel is higher in trisomy 21 than in chromosomally normal fetuses. As there is no significant association between the presence of these markers and nuchal translucency thickness, they could be included in the assessment of risk to improve accuracy of screening.

Literature Review and suggested protocol for managing ultrasound soft markers for Down syndrome: Thickened nuchal fold, echogenic bowel, shortened femur, shortened humerus, pyelectasis and absent or hypoplastic nasal bone

Mid-trimester soft markers have been linked with Down syndrome and other aneuploidies. There are many other prenatal screening tests available with better detection rates for Down syndrome than the mid-trimester ultrasound. Many patients confronted with the diagnosis of a soft marker become anxious and may request a diagnostic test (amniocentesis) despite the associated risk of miscarriage. This is also despite the fact that most fetuses with an isolated soft marker are chromosomally normal. The management of a pregnancy with a soft marker must therefore be planned in a manner designed to minimize patient anxiety. Likelihood ratios can be used to modify a patient's 'prior risk' (based on age or prior screening tests) and create a new risk. This calculation may help identify a subset of patients suitable for further investigation. It has been proposed that 'negative' likelihood ratios can be used to reduce a patient's risk if no soft marker is found at a mid-trimester ultrasound. There remain concerns about this approach and further research is required before this approach enters common practice. The published work surrounding the management of thickened nuchal fold, echogenic bowel, shortened femur, shortened humerus, pyelectasis (renal pelvis dilatation) and hypoplastic nasal bone is reviewed. Each soft marker has different associations and individual management plans for each of these soft markers are presented. Although isolated single umbilical artery is not usually considered a soft marker of aneuploidy, a management plan for this common finding is also included.

The risk of a major trisomy in fetuses with pyelectasis: the impact of an abnormal maternal serum screen or additional sonographic markers

OBJECTIVE

This study was undertaken to evaluate the contribution of either an abnormal second-trimester maternal serum screen or the presence of additional sonographic markers of aneuploidy to the risk of a major trisomy (13, 18, and 21) in fetuses with pyelectasis.

STUDY DESIGN

A retrospective review of a large amniocentesis database was performed. Specimens obtained after the sonographic detection of fetal pyelectasis were eligible for analysis. Age-matched women who underwent amniocentesis solely for maternal anxiety or advanced maternal age served as controls.

RESULTS

760,495 amniocentesis specimens were analyzed. Fetal pyelectasis was detected in 671 cases. Pyelectasis, with either a single or multiple additional sonographic markers, was associated with an 8-fold and 62-fold increase in the prevalence of major trisomies (odds ratio = 7.7, 95% CI = 1.2-32.6, P = 0.02) and (odds ratio = 61.9, 95% CI = 13.2-144.6, P < .001), respectively. Pyelectasis with an abnormal maternal serum screen, with or without additional sonographic markers, was associated with a 32-fold and a 205-fold increase in major trisomies (odds ratio = 32.2, 95% CI = 5.3-94.8, P < .001) and (odds ratio = 205.8, 95% CI = 37.9-427.6, P < .001), respectively.

CONCLUSION

In fetuses with pyelectasis, the presence of additional sonographic markers or an abnormal maternal serum screen significantly increases the risk of trisomy 13, 18, and 21.