Clinical and molecular characteristics of 26 fetuses with lethal multiple congenital contractures

Multiple congenital contractures (MCC) due to fetal akinesia manifest across a broad spectrum of diseases, ranging from mild distal arthrogryposis to lethal fetal akinesia deformation sequence. We hereby present a series of 26 fetuses displaying severe MCC phenotypes from 18 families and describe detailed prenatal ultrasound findings, postmortem clinical evaluations, and genetic investigations. Most common prenatal findings were abnormal facial profile (65%), central nervous system abnormalities (62%), polyhydramnios (50%), increased nuchal translucency (50%), and fetal hydrops (35%). Postmortem examinations unveiled additional anomalies including facial dysmorphisms, dysplastic skeletal changes, ichthyosis, multiple pterygia, and myopathy, allowing preliminary diagnosis of particular Mendelian disorders in multiple patients. Evaluation of the parents revealed maternal grip myotonia in one family. By exome sequencing and targeted testing, we identified causative variants in ACTC1, CHST14, COG6, DMPK, DOK7, HSPG2, KLHL7, KLHL40, KIAA1109, NEB, PSAT1, RAPSN, USP14, and WASHC5 in 15 families, and one patient with a plausible diagnosis associated with biallelic NEB variants. Three patients received a dual diagnosis. Pathogenic alterations in newly discovered genes or in previously known genes recently linked to new MCC phenotypes were observed in 44% of the cohort. Our results provide new insights into the clinical and molecular landscape of lethal MCC phenotypes.

An ongoing problem: Rhesus hemolytic disease of the newborn - A decade of experience in a single centre

BACKGROUND

The objectives were to evaluate the descriptive features of newborns with a diagnosis of Rhesus (Rh) hemolytic disease, to determine the morbidity and mortality rates, to evaluate the treatment methods and the factors affecting treatment requirements and clinical outcomes during a ten-year period at a tertiary center.

METHODS

Newborn infants who had a positive direct Coombs test and/or had a history of intrauterine transfusion (IUT) due to Rh hemolytic disease were included. The data regarding the prenatal, natal and postnatal periods were collected from hospital records.

RESULTS

A total of 260 neonates were included of which 51.2% were female. The mean ± standard deviation gestational age was 36.9 ± 2.7 weeks. The rate of preterm birth was 41.2%. Of 257 mothers whose obstetric medical history could be accessed, 87.2% were multigravida, whereas 76.3% were multiparous. Among mothers who had a reliable history of anti-D immunoglobulin prophylaxis (n=191), 51.3% had not received anti-D immunoglobulin prophylaxis in their previous pregnancies. The antenatal transfusion rate was 31.7% and the frequency of hydrops fetalis was 8.8%. While combined exchange transfusion (ET) and phototherapy (PT) was performed in 15.4% of the babies, the majority either needed phototherapy only (51.1%) or no treatment (33.5%). The mortality rate was 3.8 % (n = 10), and nine babies out of these 10 were those with severe hydrops fetalis.

CONCLUSION

This study showed that Rh hemolytic disease is still a major problem in developing countries. Multiple comorbidities may occur in addition to life threatening complications, including hydrops fetalis, anemia and severe hyperbilirubinemia. High rates of multiparity and low rates of anti-D immunoglobulin prophylaxis are potential barriers for the eradication of the disease. It should be remembered that Rh hemolytic disease is a preventable disease in the presence of appropriate antenatal follow-up and care facilities.

Predictive value of ultrasound in prenatal diagnosis of hypospadias: hints for accurate diagnosis

OBJECTIVES

This study aims to assess the diagnostic accuracy of targeted ultrasound examination in prenatal diagnosis of hypospadias and to evaluate the predictive values of defined ultrasonographic findings of hypospadias.

METHODS

The cases diagnosed with hypospadias in our fetal medicine center were identified on an electronic database. The ultrasound reports, images and hospital records were reviewed retrospectively. The predictive value of prenatal ultrasound diagnosis and the predictive values of each sonographic finding were assessed according to the postnatal clinical examinations.

RESULTS

Thirty-nine cases were diagnosed with hypospadias on ultrasound during the 6 years. Nine fetuses with missing postnatal examination records were excluded. Twentytwo of the remaining fetuses had their prenatal diagnosis of hypospadias confirmed in postnatal examinations, indicating a 73.3 % positive predictive value. Normal external genitalia was detected in postnatal examinations of three fetuses. Five fetuses were diagnosed with other external genital abnormalities, including micropenis (n=2), clitoromegaly (n=2), and buried penis with bifid scrotum (n=1) in postnatal examinations. The positive predictive value of prenatal ultrasound for any external genital abnormality was 90 %.

CONCLUSIONS

Although the positive predictive value of ultrasound for genital anomalies is satisfying, it is slightly lower for the specific diagnosis of hypospadias. This reflects overlapping ultrasound findings of different external genitalia anomalies. Standardized, systematic evaluation of the internal and external genital organs, karyotyping and genetic sex determination are essential to achieve a precise prenatal diagnosis of hypospadias.

The Evaluation of Adropin and Autotaxin as Potential Markers of Endothelial Dysfunction in Preeclampsia

Endothelial dysfunction (ED) plays a prominent role in the pathogenesis of preeclampsia (PE). There is a need for non-invasive methods to assess endothelial function in preeclamptic patients. In the present study, adropin, autotaxin (ATX), and lysophosphatidic acid (LPA) were evaluated as indicators of ED. Patients diagnosed with PE and healthy pregnant women (n = 42 for each group) were compared. After measuring flow-mediated dilation (FMD), the participants were stratified as ED (+) or ED (-) based on a cut-off value of 6.5%. The PE patients were divided as early/late onset PE and severe/mild PE. Adropin, ATX, and LPA levels were measured, and their relevance to ED was evaluated. Student t, Mann-Whitney U, or ANOVA tests were used for statistics, as appropriate. Adropin levels were diminished in the ED (+) group, whereas ATX and LPA levels were increased. The decrease in adropin levels was more pronounced in severe PE, showing a positive correlation with the FMD. In the logistic regression model, adropin was the only parameter that was an independent variable for the FMD test (P < .001). Adropin measurements in serum may be of value for disease follow-up in patients with PE.

Fibular Agenesis and Ball-Like Toes Mimicking Preaxial Polydactyly: Prenatal Presentation of Du Pan Syndrome

Introduction

GDF5-BMPR1B signaling pathway-associated chondrodysplasias are a genetically heterogeneous group of conditions with significant phenotypic and genotypic overlap, consisting of Hunter-Thompson-type acromesomelic dysplasia, Grebe dysplasia, and Du Pan syndrome. Constituting a spectrum of clinical severity, these disorders are characterized by disproportionate short stature mainly involving middle and distal segments of the extremities. Du Pan syndrome represents the mildest end of this spectrum with less marked shortened limbs, fibular agenesis or hypoplasia, absence of frequent joint dislocations, and carpotarsal fusions with deformed phalangeal bones.

Case Presentation

Here, we report the first prenatal diagnosis of Du Pan syndrome based on the sonographic findings of bilateral fibular agenesis and ball-shaped toes mimicking preaxial polydactyly accompanying subtle brachydactyly in the family. GDF5 (NM_000557.5) sequencing identified a homozygous pathogenic variant c.1322T>C, p.(Leu441Pro) in the fetus and confirmed the carrier status in the mother.

Discussion

We suggest that the presence of bilateral fibular agenesis and the apparent image of preaxial polydactyly of the feet on prenatal ultrasound should alert suspicion to Du Pan syndrome, with the latter possibly being a sonographic pitfall. Alongside the fetal imaging, a detailed clinical examination of the expectant parents is also of great importance in establishing a preliminary diagnosis of Du Pan syndrome, as well as the other GDF5-BMPR1B-associated chondrodysplasias.

FREM2-related Fraser syndrome with popliteal pterygium and structural central nervous system anomalies

Fraser syndrome (FS) is a rare multiple malformation disorder characterized by cryptophthalmos, characteristic craniofacial dysmorphism, cutaneous syndactyly, malformations of the respiratory and urinary tract, and anogenital anomalies. Although the characteristic presentation of FS can be detected prenatally, oligohydramnios often challenges the clinical diagnosis. Here we report on the atypical prenatal and postmortem findings of a fetus with FS caused by a novel homozygous frameshift variant in FREM2. Our study highlights the variable manifestations of the FS and expands the clinical spectrum to include popliteal pterygium and structural central nervous system anomalies.

Fetal skeletal dysplasia cohort of a single tertiary referral center in Istanbul, Turkey

We report on 314 fetal cases from 297 unrelated families with skeletal dysplasia evaluated in the postmortem period from 2000 to 2017 at a single clinical genetics center in İstanbul, Turkey. The definite diagnostic yield was 40% during the prenatal period, while it reached 74.5% when combined with postmortem clinical and radiological evaluation. Molecular analyses were performed in 25.5% (n: 76) of families, and 21 novel variants were identified. Classification according to International Skeletal Dysplasia Society-2019 revision revealed limb hypoplasia-reduction defects group (39) as the leading one, 24.5%, then followed by FGFR3 chondrodysplasias, osteogenesis imperfecta, and decreased mineralization and polydactyly-syndactyly-triphalangism groups 13.6, 11.1, and 8.9%, respectively. The inheritance pattern was autosomal recessive in 54% and autosomal dominant in 42.6% of index cases. The overall consanguinity rate of the cohort was 33%. The high prevalence of ultrarare diseases along with two or more unrelated autosomal recessive entities running in the same family was noteworthy. This study highlights the pivotal role of postmortem evaluation by an experienced clinical geneticist to achieve a high diagnostic yield in fetal skeletal dysplasia cohorts. The cohort is not only a representation of the spectrum of skeletal dysplasias in a population with a high consanguinity rate but also provides an ideal research group to work on to identify the unknowns of early fetal life.

Prenatal ultrasonographic features in Blomstrand osteochondrodysplasia: Antenatal case series confirmed by postmortem radiology and molecular diagnosis

OBJECTIVE

Blomstrand osteochondrodysplasia (BOCD, MIM #215045) is an ultrarare lethal skeletal dysplasia (LSD) perinatally, characterized by extremely advanced bone maturation, generalized osteosclerosis, and severe tetramicromelia caused by biallelic loss-of-function mutations in the parathyroid hormone receptor-1 gene (PTHR1). We aim to describe prenatal ultrasonographic features in a retrospective fetal case series of BOCD and emphasize the importance of multidisciplinary antenatal evaluation of LSDs to improve the differential diagnosis.

METHOD

Prenatal ultrasound findings of five fetal cases diagnosed with BOCD between 2000 and 2019 in the Prenatal Diagnosis Unit and Medical Genetics were reviewed, along with postmortem examination results and confirmatory molecular results.

RESULTS

All fetuses presented with severe sonographic findings of LSDs comprising tetramicromelia, thoracic hypoplasia, and retro-micrognathia. Marked cervical hyperextension was present in three fetuses. Flared metaphyses were prenatally identified in only one fetus. X-rays of four fetuses evaluated postmortem showed advanced bone maturation, generalized osteosclerosis, and dumbbell-like appearance of long bones due to metaphyseal enlargement.

CONCLUSION

The presence of retro-micrognathia along with a protruding tongue and severe metaphyseal flaring can suggest a diagnosis of BOCD, when prenatal ultrasound findings are indicative for LSD. The diagnosis can be ascertained through postmortem clinical and radiological evaluation and/or molecular testing.

Salvage for Postpartum Massive Haemorrhage in a Jehovah's Witness with Intravenous Iron Therapy and Cell Saver System

Intraoperative cell salvage (ICS) system performs autologous transfusion by filtering and reinfusing the shed blood into corporeal circulation during the surgery. Especially for pregnant Jehovah's Witnesses, the ICS system could be a life-saving intervention. This report describes the successful use of intravenous iron therapy and ICS during the cesarean delivery of a Jehovah's Witness diagnosed with placenta previa totalis who refused to receive any type of blood or blood product transfusion. Intravenous iron treatment initiated in the preoperative period can reduce the need for blood and blood product transfusion. The ICS system provides recognised advantages; however, its utilisation requires high technology equipment and skilled health staff. Key Words: Jehovah's witness, pregnancy, Iron therapy, Intraoperative cell salvage.

Antenatal diagnostic dilemma in a pseudodominant pedigree with lamin-B receptor (LBR)-related regressive spondylometaphyseal dysplasia

The lamin-B receptor (LBR) encodes a dual-functioning inner nuclear membrane protein essential for cholesterol biosynthesis and chromatin organization. LBR pathogenic variants cause distinct phenotypes due to the dual function of LBR, including Pelger-Huët anomaly (PHA), PHA with mild skeletal anomalies (PHASK; MIM# 618019), LBR-related regressive type of spondylometaphyseal dysplasia (LBR-R-SMD), Greenberg dysplasia (MIM# 215140). We here report the first case with radiological manifestations of LBR-R-SMD in the fetal period, and milder skeletal findings in the similarly affected father. Direct sequencing of LBR revealed homozygous c.1534C>T (p.Arg512Trp) in exon 12 in both affected individuals. Our report further refines the early phenotype in LBR-R-SMD, and demonstrates that the p.Arg512Trp mutation is associated with PHA. We propose that LBR-R-SMD should be considered as a differential diagnosis in pregnancies with sonographic evidence of short and bowed tubular bones with narrow thorax. Evaluating peripheral blood smears of expectant parents for the presence of PHA may lead to a clinical diagnosis, allowing for comprehensive prenatal genetic counseling.

Prenatal sonographic and cytogenetic/molecular findings of 22q11.2 microdeletion syndrome in 48 confirmed cases in a single tertiary center

PURPOSE

We aimed to present the fetal ultrasound, cytogenetic/molecular testing and postmortem or postnatal clinical findings of cases with 22q11.2DS diagnosed prenatally.

MATERIALS AND METHODS

A retrospective medical record review of 48 prenatal cases diagnosed with 22q11.2DS were evaluated in our institution. Detailed ultrasound examination was performed on all fetuses. Postmortem and postnatal examinations were evaluated. The microdeletions were detected by karyotyping or microarray, then confirmed by FISH. Descriptive statistical analysis was performed.

RESULTS

Demographic data of 48 prenatal cases including 46 singletons and 1 dichorionic diamniotic twin pregnancy were evaluated. The most common extracardiac anomaly was skeletal system anomalies (25%), in which PEV was the most frequent one (20.8%). Polyhydramnios rate was detected as 31%, in 6.6% as an isolated finding. Microdeletion has been detected by karyotyping in 13 cases (13/47, 27.7%) (including 2 unbalanced translocations), by FISH in 28 cases (28/48, 58.3%), by microarray/a-CGH testing in 7 cases. Microarray analysis showed that in one case with unbalanced translocation had two consecutive deletions; one was proximal and other one distal to critical region and not encompassing TBX1 gene but CRKL and LZTR1 genes.

CONCLUSION

The current study demonstrates the whole spectrum of atypical phenotypic and genotypic variations of 22q11.2DS in the largest prenatal case series reported to date. Therefore, differential diagnosis should be considered not solely in CHD, but also in the presence of isolated clubfeet and polyhydramnios. Establishing the diagnosis in the prenatal period may allow a postnatal multidisciplinary approach, as well as affect the actual prevalence of the disease.

Prenatal Diagnosis and Findings in Ureteropelvic Junction Type Hydronephrosis

The widespread use of obstetric ultrasonography has increased the detection rate of antenatal hydronephrosis. Although most cases of antenatal hydronephrosis are transient, one third persists and becomes clinically important. Ultrasound has made differential diagnosis possible to some extent. Ureteropelvic junction type hydronephrosis (UPJHN) is one of the most common cause of persistent fetal hydronephrosis and occurs three times more in male fetuses. It is usually sporadic and unilateral. However, when bilateral kidneys are involved and presents with severe hydronephrosis, the prognosis may be poor. Typical ultrasound findings of UPJHN is hydronephrosis without hydroureter. The size and appearance of the fetal bladder is usually normal without thickening of the bladder wall. Several grading systems are developed and increasingly being used to define the severity of prenatal hydronephrosis and provides much more information about prediction of postnatal renal prognosis. If fetal urinary tract dilation is detected; laterality, severity of hydronephrosis, echogenicity of the kidneys, presence of ureter dilation should be assessed. Bladder volume and emptying, sex of the fetus, amniotic fluid volume, and presence of associated malformations should be evaluated. Particularly the ultrasonographic signs of renal dysplasia, such as increased renal parenchymal echogenicity, thinning of the renal cortex, the presence of cortical cysts, and co-existing oligohydramnios should be noticed. Unfortunately, there is no reliable predictor of renal function in UPJHN cases. Unilateral hydronephrosis cases suggesting UPJHN are mostly followed up conservatively. However, the cases with bilateral involvement are still difficult to manage. Timing of delivery is also controversial.

Follow-Up Studies of cf-DNA Testing from 101 Consecutive Fetuses and Related Ultrasound Findings

PURPOSE

 To determine the true- and false-positive rates of cf-DNA testing in a cohort of patients from tertiary care centers and assess the impact of ultrasound examinations in pregnancy management.

MATERIALS AND METHODS

 Clinical, cytogenetic and ultrasound data of 101 consecutive fetuses were collected retrospectively. Cases were classified into five groups according to the ultrasound findings. Karyotyping, interphase FISH and microarray techniques were used for follow-up studies.

RESULTS

 The overall false-positive rate was low for trisomy 21 (T21, 8.2 %), but significantly higher for trisomy 18 (T18, 40 %), monosomy X (MX, 50 %), X/Y trisomies (57.1 %), trisomy 13 (T13, 71.4 %). While single cases of trisomy 16, trisomy 22 and 8q duplication positive in cf-DNA were confirmed, 3 microdeletions (1p36 and two 22q11.2) were not. About 75 % of confirmed T21's and all confirmed T18 and T13 had major markers and/or malformations. While false-negative cases (two T21, one T18 and one T13) were identified due to abnormal ultrasound findings, all false-positive cases were normal sonographically. Ultrasound findings of confirmed trisomy 16, 22, dup8q, monosomy X and other X/Y aneuploidies were unspecific. Term placenta studies were helpful to assess the role of confined mosaicism in unconfirmed cf-DNA test results. A vanishing twin has been observed as the likely cause of one false-positive T18.

CONCLUSION

 Our study contributes clinical data on discrepant cf-DNA testing results, corroborates the need for confirmational invasive testing and underscores the benefit of expert ultrasound in the prevention of fatal diagnostic errors.

Evaluation of respiratory syncytial virus IgG antibody dynamics in mother-infant pairs cohort

RSV is one of the most important agents of lower respiratory infections in childhood. In this study, anti-RSV antibody levels in mother-infant pairs and factors related to antibody transfer ratio were investigated. One hundred and twenty-seven women that had term babies and their babies and 84 mother-infant pairs of them who continued the study after 6 months were enrolled. Anti-RSV IgG antibodies of the mothers and infants were positive in 46.5% and 61.5%, respectively. At the sixth month, anti-RSV antibodies were negative in all infants. Median of the anti-RSV antibody levels of the mothers and infants at birth were 12.08 IU/ml (1.21-119.27) and 13.78 IU/ml (3.99-108.6), respectively. There was a significant correlation between anti-RSV antibody levels of mothers and infants at birth (p: 0.0001, r: 0.667) and anti-RSV antibody levels of infants at birth and at 6th month (p: 0.0001, r: 0.343). Median ratio of infant and mother antibody levels was 1.22 (0.14-6.05). Median ratio that was detected in appropriate for gestational age infants was significantly higher than in small for gestational age or large for gestational age infants. In this study, the significant positive correlation between maternal antibody levels and infants' antibody levels at birth suggests that maternal vaccination strategies may be logical. We showed that antibody transfer rate was highest in appropriate for gestational age infants. It should be kept in mind that maternal vaccination strategies may be less effective in small for gestational age and large for gestational age infants.

Utilization of neurosonography for evaluation of the corpus callosum malformations in the era of fetal magnetic resonance imaging

AIM

We evaluated the ability of fetal neurosonography and magnetic resonance imaging (MRI) to asses callosal anomalies (CA) and associated cranial malformations. We also aimed to determine the long-term prognosis of the cases.

METHODS

Thirty-six cases of CA diagnosed combined with neurosonography and MRI between January 2012 and October 2017 were retrospectively reviewed.

RESULTS

Seventeen of 36 fetuses were diagnosed complete agenesis of corpus callosum (CACC) (47.2%), 9 had partial agenesis of corpus callosum (PACC) (25%) and 10 was dysgenesis of the corpus callosum (DCC) (27.2%) at ultrasonography (US) examination. Fetal MRI reported 16 of cases as CACC (44.4%), 11 PACC (30.5%) and nine (25%) DCC. The overall consistency between neurosonography and MRI in the definition of CA were 91% of cases. Sulcation anomalies were present in 9 cases in the US (25%) and 11 cases in MRI (30.4%). Seven of cases showed posterior fossa abnormalities in the US (19.4%) and eight cases in MRI (22.1%). Neonatal MRI added new findings to fetal MRI and neurosonography including grade-1 intraventricular hemorrhage and periventricular leukomalacia in two cases (12.5%). Eighteen cases were terminated (50%), 17 cases were followed up and mean follow up interval was 39 ± 5.1 months. The neurologic outcome was abnormal in seven (41.7%) patients. Presence of associated brain anomalies worsened the prognosis.

CONCLUSION

Fetal neurosonography has a comparable performance with MRI in the diagnosis of CA and associated anomalies. It should be used in collaboration with MRI to achieve accurate diagnosis which is crucial for counseling.

Prenatal Diagnosis of Persistent Hyperplastic Primary Vitreous: Report of 2 Cases and Review of the Literature

Persistent hyperplastic primary vitreous is a spectrum of congenital ocular abnormalities characterized by leukocoria, microphthalmia, cataracts, extensive intravitreal hemorrhage, persistence of the hyaloid artery, glaucoma, and retinal detachment. It might be isolated or associated with congenital syndromes such as trisomy 13, Walker-Warburg syndrome, and Norrie disease. We present 2 cases of persistent hyperplastic primary vitreous diagnosed by prenatal sonography in the early third trimester. Bilateral hyperechoic lenses and retinal nonattachment were detected in the sonographic examination of the first case, whereas irregular echogenic bands between the lenses and posterior walls of the eyes were prominent in the second case. In both of the cases, ocular findings were accompanied by intracranial findings, including severe hydrocephalus, an abnormal gyral pattern, and cerebellar hypoplasia, suggesting the diagnosis of Walker-Warburg syndrome. We also present a review of the literature regarding the prenatal diagnosis of this malformation.

Prenatal diagnosis of tethered spinal cord associated with sacrococcygeal teratoma

Tethered spinal cord is mostly caused by myelomeningocele and lipomyelomeningocele, while dermal sinus tract, diastematomyelia, lipoma, tumor, thickened/tight filum terminale, spinal trauma, and spinal surgery are among the other causes. Prenatal diagnosis of tethered cord has been reported, and it is usually associated with neural tube defects. We present an atypical presentation of a tethered spinal cord, which was associated with a sacrococcygeal teratoma and was diagnosed in the 23rd week of pregnancy by ultrasonography. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:506-509, 2016.

Evaluation of fetal subarachnoid space using transabdominal ultrasonography and normal values during pregnancy

Objectives

To determine the feasibility of evaluating the subarachnoid space by measuring two novel sonographic parameters in axial section using transabdominal ultrasound, in addition to the parameters previously defined in coronal section, and to construct a normal range for the subarachnoid space width in singleton healthy fetuses.

Methods

Healthy pregnant women between 20 and 29 weeks were scanned using transabdominal ultrasound. Four variables were measured for the evaluation of subarachnoid space width; sinocortical width and anterior craniocortical width in coronal plane, and lateral and posterior craniocortical width in axial plane.

Result

The data of 154 patients were recorded. SCW could be measured in 87.6 % (135) of fetuses, while the same figure was 77.9 % (120), 96.1 % (151) and 98.1 % (148) for anterior, lateral and posterolateral CCW, respectively. The SCW and anterior CCW did not display a significant correlation with gestational age and head circumference. The mean of SCW was 1.55 ± 0.41 mm with a range of 0.85–3.87 mm. The mean anterior CCW was 1.63 ± 0.39 mm with a range of 0.85–2.82 mm. A linear regression line was plotted between gestational age and lateral CCW (r = 0.707; p < 0.0001) and posterolateral CCW (r = 0.437; p < 0.0001), and nomograms for these parameters are constructed.

Conclusion

This study presents a novel approach for the in utero evaluation of the subarachnoid space with two measurements in axial plane using transabdominal ultrasound. The nomograms will be helpful when there is a suspicion of subarachnoid space dilatation during routine cranial scan.