ABSTRACT
INTRODUCTION: Congenital disorders of glycosylation (CDG) are a continuously expanding group of monogenic disorders that disrupt glycoprotein and glycolipid biosynthesis, leading to multi-systemic manifestations. These disorders are categorized into various groups depending on which part of the glycosylation process is impaired. The cardiac manifestations in CDG can significantly differ, not only across different types but also among individuals with the same genetic cause of CDG. Cardiomyopathy is an important phenotype in CDG. The clinical manifestations and progression of cardiomyopathy in CDG patients have not been well characterized. This study aims to delineate common patterns of cardiomyopathy across a range of genetic causes of CDG and to propose baseline screening and follow-up evaluation for this patient population. METHODS: Patients with molecular confirmation of CDG who were enrolled in the prospective or memorial arms of the Frontiers in Congenital Disorders of Glycosylation Consortium (FCDGC) natural history study were ascertained for the presence of cardiomyopathy based on a retrospective review of their medical records. All patients were evaluated by clinical geneticists who are members of FCDGC at their respective academic centers. Patients were screened for cardiomyopathy, and detailed data were retrospectively collected. We analyzed their clinical and molecular history, imaging characteristics of cardiac involvement, type of cardiomyopathy, age at initial presentation of cardiomyopathy, additional cardiac features, the treatments administered, and their clinical outcomes. RESULTS: Of the 305 patients with molecularly confirmed CDG participating in the FCDGC natural history study as of June 2023, 17 individuals, nine females and eight males, were identified with concurrent diagnoses of cardiomyopathy. Most of these patients were diagnosed with PMM2-CDG (n = 10). However, cardiomyopathy was also observed in other diagnoses, including PGM1-CDG (n = 3), ALG3-CDG (n = 1), DPM1-CDG (n = 1), DPAGT1-CDG (n = 1), and SSR4-CDG (n = 1). All PMM2-CDG patients were reported to have hypertrophic cardiomyopathy. Dilated cardiomyopathy was observed in three patients, two with PGM1-CDG and one with ALG3-CDG; left ventricular non-compaction cardiomyopathy was diagnosed in two patients, one with PGM1-CDG and one with DPAGT1-CDG; two patients, one with DPM1-CDG and one with SSR4-CDG, were diagnosed with non-ischemic cardiomyopathy. The estimated median age of diagnosis for cardiomyopathy was 5 months (range: prenatal-27 years). Cardiac improvement was observed in three patients with PMM2-CDG. Five patients showed a progressive course of cardiomyopathy, while the condition remained unchanged in eight individuals. Six patients demonstrated pericardial effusion, with three patients exhibiting cardiac tamponade. One patient with SSR4-CDG has been recently diagnosed with cardiomyopathy; thus, the progression of the disease is yet to be determined. One patient with PGM1-CDG underwent cardiac transplantation. Seven patients were deceased, including five with PMM2-CDG, one with DPAGT1-CDG, and one with ALG3-CDG. Two patients died of cardiac tamponade from pericardial effusion; for the remaining patients, cardiomyopathy was not necessarily the primary cause of death. CONCLUSIONS: In this retrospective study, cardiomyopathy was identified in â¼6% of patients with CDG. Notably, the majority, including all those with PMM2-CDG, exhibited hypertrophic cardiomyopathy. Some cases did not show progression, yet pericardial effusions were commonly observed, especially in PMM2-CDG patients, occasionally escalating to life-threatening cardiac tamponade. It is recommended that clinicians managing CDG patients, particularly those with PMM2-CDG and PGM1-CDG, be vigilant of the cardiomyopathy risk and risk for potentially life-threatening pericardial effusions. Cardiac surveillance, including an echocardiogram and EKG, should be conducted at the time of diagnosis, annually throughout the first 5 years, followed by check-ups every 2-3 years if no concerns arise until adulthood. Subsequently, routine cardiac examinations every five years are advisable. Additionally, patients with diagnosed cardiomyopathy should receive ongoing cardiac care to ensure the effective management and monitoring of their condition. A prospective study will be required to determine the true prevalence of cardiomyopathy in CDG.
Subject(s)
Cardiomyopathies , Congenital Disorders of Glycosylation , Phenotype , Humans , Congenital Disorders of Glycosylation/genetics , Congenital Disorders of Glycosylation/diagnosis , Congenital Disorders of Glycosylation/pathology , Female , Male , Cardiomyopathies/genetics , Cardiomyopathies/diagnosis , Child , Child, Preschool , Adolescent , Infant , Glycosylation , Follow-Up Studies , Adult , Retrospective Studies , Young Adult , Prospective Studies , Infant, NewbornABSTRACT
OBJECTIVE: Our report describes clinical, genetic, and biochemical features of participants with a molecularly confirmed congenital disorder of glycosylation (CDG) enrolled in the Frontiers in Congenital Disorders of Glycosylation (FCDGC) Natural History cohort at year 5 of the study. METHODS: We enrolled individuals with a known or suspected CDG into the FCDGC Natural History Study, a multicenter prospective and retrospective natural history study of all genetic causes of CDG. We conducted a cross-sectional analysis of baseline study visit data from participants with confirmed CDG who were consented into the FCDGC Natural History Study (5U54NS115198) from October 2019 to November 2023. RESULTS: Three hundred thirty-three subjects consented to the FCDGC Natural History Study. Of these, 280 unique individuals had genetic data available that was consistent with a diagnosis of CDG. These 280 individuals were enrolled into the study between October 8, 2019 and November 29, 2023. One hundred forty-one (50.4%) were female, and 139 (49.6%) were male. Mean and median age at enrollment was 10.1 and 6.5 years, respectively, with a range of 0.22 to 71.4 years. The cohort encompassed individuals with disorders of N-linked protein glycosylation (57%), glycosylphosphatidylinositol anchor disorder (GPI anchor) (15%), disorders of Golgi homeostasis, trafficking and transport (12%), dolichol metabolism disorders (5%), disorders of multiple pathways (6%), and other (5%). The most frequent presenting symptom(s) leading to diagnosis were developmental delay/disability (77%), followed by hypotonia (56%) and feeding difficulties (42%). Mean and median time between first related symptom and diagnosis was 2.7 and 0.8 years, respectively. One hundred percent of individuals in our cohort had developmental differences/disabilities at the time of their baseline visit, followed by 97% with neurologic involvement, 91% with gastrointestinal (GI)/liver involvement, and 88% with musculoskeletal involvement. Severity of disease in individuals was scored on the Nijmegen Progression CDG Rating Scale (NPCRS) with 27% of scores categorized as mild, 44% moderate, and 29% severe. Of the individuals with N-linked protein glycosylation defects, 83% of those with data showed a type 1 pattern on carbohydrate deficient transferrin (CDT) analysis including 82/84 individuals with PMM2-CDG, 6% a type 2 pattern, 1% both type 1 and type 2 pattern and 10% a normal or nonspecific pattern. One hundred percent of individuals with Golgi homeostasis and trafficking defects with data showed a type 2 pattern on CDT analysis, while Golgi transport defect showed a type II pattern 73% of the time, a type 1 pattern for 7%, and 20% had a normal or nonspecific pattern. Most of the variants documented were classified as pathogenic or likely pathogenic using ACMG criteria. For the majority of the variants, the predicted molecular consequence was missense followed by nonsense and splice site, and the majority of the diagnoses are inherited in an autosomal recessive pattern but with disorders of all major nuclear inheritance included. DISCUSSION: The FCDGC Natural History Study serves as an important resource to build future research studies, improve clinical care, and prepare for clinical trial readiness. Herein is the first overview of CDG participants of the FCDGC Natural History Study.
Subject(s)
Congenital Disorders of Glycosylation , Humans , Congenital Disorders of Glycosylation/genetics , Congenital Disorders of Glycosylation/pathology , Male , Female , Cross-Sectional Studies , Child , Child, Preschool , Adolescent , Glycosylation , Adult , Retrospective Studies , Infant , Young Adult , Prospective Studies , Cohort StudiesABSTRACT
Hypoxic-ischemic encephalopathy (HIE) occurs in up to 7 out of 1000 births and accounts for almost a quarter of neonatal deaths worldwide. Despite the name, many newborns with HIE have little evidence of perinatal hypoxia. We hypothesized that some infants with HIE have genetic disorders that resemble encephalopathy. We reviewed genetic results for newborns with HIE undergoing exome or genome sequencing at a clinical laboratory (2014-2022). Neonates were included if they had a diagnosis of HIE and were delivered ≥35 weeks. Neonates were excluded for cardiopulmonary pathology resulting in hypoxemia or if neuroimaging suggested postnatal hypoxic-ischemic injury. Of 24 patients meeting inclusion criteria, six (25%) were diagnosed with a genetic condition. Four neonates had variants at loci linked to conditions with phenotypic features resembling HIE, including KIF1A, GBE1, ACTA1, and a 15q13.3 deletion. Two additional neonates had variants in genes not previously associated with encephalopathy, including DUOX2 and PTPN11. Of the six neonates with a molecular diagnosis, two had isolated HIE without apparent comorbidities to suggest a genetic disorder. Genetic diagnoses were identified among neonates with and without sentinel labor events, abnormal umbilical cord gasses, and low Apgar scores. These results suggest that genetic evaluation is clinically relevant for patients with perinatal HIE.
Subject(s)
Exome Sequencing , Hypoxia-Ischemia, Brain , Humans , Hypoxia-Ischemia, Brain/genetics , Hypoxia-Ischemia, Brain/diagnosis , Hypoxia-Ischemia, Brain/diagnostic imaging , Infant, Newborn , Female , Male , Retrospective Studies , Genetic Predisposition to Disease , Exome/genetics , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/diagnosisABSTRACT
INTRODUCTION: Insulin requirement in women with Type 1 diabetes (T1DM) changes throughout pregnancy. The aim of this study was to determine the total change in insulin requirements and the effect of gestational weight gain (GWG) and pre-gestational BMI on insulin requirements during pregnancy in women with T1DM treated with continuous subcutaneous insulin infusion and continuous glucose monitoring. METHODS: This historical cohort study included all consecutive women with T1DM who were monitored during pregnancy at the high-risk pregnancy clinic at a tertiary medical center during April 2011-April 2019. One Way Repeated Measures ANOVA with Bonferroni adjustment was conducted to compare the effects of gestational age on insulin requirements and a Two Way Repeated Measures ANOVA was employed to test for the interaction between gestational age intervals and maternal BMI and GWG. RESULTS: Data regarding insulin requirements of 185 pregnancies were included in the analyses. There was a significant effect of gestational age on total insulin (Wilks' Lambda = 0.34, F(6,14) = 4.52, p = 0.009), basal insulin (Wilks' Lambda = 0.41, F(6,14) = 3.30, p = 0.031) and bolus insulin (Wilks' Lambda = 0.43, F(6,14) = 3.02, p = 0.041). Total insulin/kg requirements increased by 5.5% from 13-20 weeks to 20-26 weeks, 19% from 20-26 weeks to 26-33 weeks, and 17.4% from 26 to 33 weeks to delivery (p for trend = 0.009). Overall, insulin requirements increased by 42.1% from conception to delivery (p < 0.01). There was no significant main effect of maternal BMI or GWG on insulin requirements. CONCLUSIONS: There is a significant increase in insulin requirements per kg during pregnancy in women with T1DM who were treated with an insulin pump.
Subject(s)
Diabetes Mellitus, Type 1 , Diabetes, Gestational , Pregnancy , Female , Humans , Insulin/therapeutic use , Diabetes Mellitus, Type 1/drug therapy , Cohort Studies , Blood Glucose Self-Monitoring , Blood Glucose , Insulin, Regular, Human , Body Mass Index , Pregnancy Outcome , Retrospective StudiesABSTRACT
INTRODUCTION: Neonates of individuals with type 1 diabetes (T1D) are at increased risk of neonatal hypoglycaemia. It is hypothesised that this is a result of birthing-individual hyperglycaemia and subsequent foetal hyperinsulinemia. AIMS: To test for association between clinically significant neonatal hypoglycaemia (requiring intravenous glucose treatment) and cord-blood c-peptide (CBCP) concentrations in birthing-individuals with T1D. MATERIALS AND METHODS: This is a prospective cohort study of individuals with T1D followed at a single tertiary centre. Clinical variables and glucose control during pregnancy were recorded. Cord-blood was collected and CBCP concentrations determined. The correlation between clinically significant neonatal hypoglycaemia and CBCP concentrations was determined. RESULTS: Fifty-four pregnant individuals and their newborns were included in the study. Individuals to neonates who experienced hypoglycaemia had longer diabetes duration (19 vs. 13 years, respectively, p = 0.023), higher HbA1c at conception (7.3 [6.3-8.8] vs. 6.5 [6.0-7.0], respectively, p = 0.042) and higher rates of caesarian section (73.3% vs. 28.2%, respectively, p = 0.005) than individuals to those who did not. CBCP levels were significantly higher in neonates with clinically significant neonatal hypoglycaemia as compared to those who did not experience hypoglycaemia (3.3 mcg/L vs. 1.9 mcg/L, respectively, p = 0.002). After adjustment for possible confounders, every 1 unit higher in CBCP level was associated with a 1.46 (1.02-2.09, p = 0.035)-fold greater risk for neonatal hypoglycaemia. No significant differences were observed in either birthing individual complications or glucose control indices during pregnancy between the two groups. CONCLUSIONS: In neonates of individuals with T1D, higher CBCP levels are an independent risk factor for clinically significant neonatal hypoglycaemia.
Subject(s)
Diabetes Mellitus, Type 1 , Hypoglycemia , Pregnancy , Female , Infant, Newborn , Humans , Diabetes Mellitus, Type 1/drug therapy , Blood Glucose , C-Peptide , Fetal Blood , Prospective Studies , Hypoglycemia/etiologyABSTRACT
BACKGROUND: Amniocentesis for genetic diagnosis is most commonly done between 15 and 22 weeks of gestation but can be performed at later gestational ages. The safety and genetic diagnostic accuracy of amniocentesis have been well-established through numerous large-scale multicenter studies for procedures before 24 weeks, but comprehensive data on late amniocentesis remain sparse. OBJECTIVE: To evaluate the indications, diagnostic yield, safety, and maternal and fetal outcomes associated with amniocentesis performed at or beyond 24 weeks of gestation. STUDY DESIGN: We conducted an international multicenter retrospective cohort study examining pregnant individuals who underwent amniocentesis for prenatal diagnostic testing at gestational ages between 24w0d and 36w6d. The study, spanning from 2011 to 2022, involved 9 referral centers. We included singleton or twin pregnancies with documented outcomes, excluding cases where other invasive procedures were performed during pregnancy or if amniocentesis was conducted for obstetric indications. We analyzed indications for late amniocentesis, types of genetic tests performed, their results, and the diagnostic yield, along with pregnancy outcomes and postprocedure complications. RESULTS: Of the 752 pregnant individuals included in our study, late amniocentesis was primarily performed for the prenatal diagnosis of structural anomalies (91.6%), followed by suspected fetal infection (2.3%) and high-risk findings from cell-free DNA screening (1.9%). The median gestational age at the time of the procedure was 28w5d, and 98.3% of pregnant individuals received results of genetic testing before birth or pregnancy termination. The diagnostic yield was 22.9%, and a diagnosis was made 2.4 times more often for fetuses with anomalies in multiple organ systems (36.4%) compared to those with anomalies in a single organ system (15.3%). Additionally, the diagnostic yield varied depending on the specific organ system involved, with the highest yield for musculoskeletal anomalies (36.7%) and hydrops fetalis (36.4%) when a single organ system or entity was affected. The most prevalent genetic diagnoses were aneuploidies (46.8%), followed by copy number variants (26.3%) and monogenic disorders (22.2%). The median gestational age at delivery was 38w3d, with an average of 59 days between the procedure and delivery date. The overall complication rate within 2 weeks postprocedure was 1.2%. We found no significant difference in the rate of preterm delivery between pregnant individuals undergoing amniocentesis between 24 and 28 weeks and those between 28 and 32 weeks, reinforcing the procedure's safety across these gestational periods. CONCLUSION: Late amniocentesis, at or after 24 weeks of gestation, especially for pregnancies complicated by multiple congenital anomalies, has a high diagnostic yield and a low complication rate, underscoring its clinical utility. It provides pregnant individuals and their providers with a comprehensive diagnostic evaluation and results before delivery, enabling informed counseling and optimized perinatal and neonatal care planning.
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OBJECTIVE: To evaluate the prenatal diagnosis of closed dysraphism (CD) and its correlation with postnatal findings and neonatal adverse outcomes. METHODS: A retrospective cohort study including pregnancies diagsnosed with fetal CD by prenatal ultrasound (US) and magnetic resonance imaging (MRI) at a single tertiary center between September 2011 and July 2021. RESULTS: CD was diagnosed prenatally and confirmed postnatally in 12 fetuses. The mean gestational age of prenatal imaging was 24.2 weeks, in 17% the head circumference was ≤fifth percentile and in 25% the cerebellar diameter was ≤fifth percentile. US findings included banana sign in 17%, and lemon sign in 33%. On MRI, posterior fossa anomalies were seen in 33% of cases, with hindbrain herniation below the foramen magnum in two cases. Mean clivus-supraocciput angle (CSA) was 74°. Additional anomalies outside the CNS were observed in 50%. Abnormal foot position was demonstrated prenatally in 17%. Neurogenic bladder was present in 90% of patients after birth. CONCLUSION: Arnold Chiari II malformation and impaired motor function can be present on prenatal imaging of fetuses with CD and may be associated with a specific type of CD. Prenatal distinction of CD can be challenging. Associated extra CNS anomalies are frequent and the rate of neurogenic urinary tract dysfunction is high.
Subject(s)
Arnold-Chiari Malformation , Nervous System Malformations/diagnosis , Spinal Dysraphism , Pregnancy , Female , Infant, Newborn , Humans , Infant , Retrospective Studies , Prenatal Diagnosis/methods , Magnetic Resonance Imaging/methods , Ultrasonography, Prenatal/methodsABSTRACT
We previously reported a fetus with Fanconi anemia (FA), complementation group O due to compound heterozygous variants involving RAD51C. Interestingly, the trio exome sequencing analysis also detected eight apparent de novo mosaic variants with variant allele fraction (VAF) ranging between 11.5 and 37%. Here, using whole genome sequencing and a 'home-brew' variant filtering pipeline and DeepMosaic module, we investigated the number and signature of de novo heterozygous and mosaic variants and the hypothesis of a rare phenomenon of hypermutation. Eight-hundred-thirty apparent de novo SNVs and 21 de novo indels had VAFs below 37.41% and were considered postzygotic somatic mosaic variants. The VAFs showed a bimodal distribution, with one component having an average VAF of 25% (range: 18.7-37.41%) (n = 446), representing potential postzygotic first mitotic events, and the other component with an average VAF of 12.5% (range 9.55-18.69%) (n = 384), describing potential second mitotic events. No increased rate of CNV formation was observed. The mutational pattern analysis for somatic single base substitution showed SBS40, SBS5, and SBS3 as the top recognized signatures. SBS3 is a known signature associated with homologous recombination-based DNA damage repair error. Our data demonstrate that biallelic RAD51C variants show evidence for defective genomic DNA damage repair and thereby result in a hypermutator phenotype with the accumulation of postzygotic de novo mutations, at least in the prenatal period. This 'genome hypermutator phenomenon' might contribute to the observed hematological manifestations and the predisposition to tumors in patients with FA. We propose that other FA groups should be investigated for genome-wide de novo variants.
Subject(s)
Fanconi Anemia , Genetic Predisposition to Disease , Humans , DNA-Binding Proteins/genetics , Fanconi Anemia/genetics , Fanconi Anemia/pathology , PhenotypeABSTRACT
AIMS: One of the most common complications of pregnancy is gestational diabetes mellitus (GDM), which may result in significant health threats of the mother, fetus and the newborn. Fatty acid-binding protein 4 (FABP4) is an adipokine that regulates glucose homeostasis by promoting glucose production and liver insulin resistance in mouse models. FABP4 levels are increased in GDM and correlates with maternal indices of insulin resistance, with a rapid decline post-partum. We therefore aimed to determine the tissue origin of elevated circulating FABP4 levels in GDM and to assess its potential contribution in promoting glucagon-induced hepatic glucose production. MATERIALS AND METHODS: FABP4 protein and gene expression was determined in biopsies from placenta, subcutaneous (sWAT) and visceral (vWAT) white adipose tissues from GDM and normoglycaemic pregnant women. FABP4 differential contribution in glucagon-stimulated hepatic glucose production was tested in conditioned media before and after its immune clearance. RESULTS: We showed that FABP4 is expressed in placenta, sWAT and vWAT of pregnant women at term, with a significant increase in its secretion from vWAT of women with GDM compared with normoglycaemic pregnant women. Neutralizing FABP4 from both normoglycaemic pregnant women and GDM vWAT secretome, resulted in a decrease in glucagon-stimulated hepatic glucose production. CONCLUSIONS: This study provides new insights into the role of adipose tissue-derived FABP4 in GDM, highlighting this adipokine, as a potential co-activator of glucagon-stimulated hepatic glucose production during pregnancy.
Subject(s)
Diabetes, Gestational , Fatty Acid-Binding Proteins , Insulin Resistance , Animals , Female , Humans , Infant, Newborn , Mice , Pregnancy , Adipokines , Adipose Tissue/metabolism , Fatty Acid-Binding Proteins/metabolism , Glucagon/metabolism , Glucose/metabolism , Insulin Resistance/physiology , Liver/metabolismABSTRACT
Technological advances in both genome sequencing and prenatal imaging are increasing our ability to accurately recognize and diagnose Mendelian conditions prenatally. Phenotype-driven early genetic diagnosis of fetal genetic disease can help to strategize treatment options and clinical preventive measures during the perinatal period, to plan in utero therapies, and to inform parental decision-making. Fetal phenotypes of genetic diseases are often unique and at present are not well understood; more comprehensive knowledge about prenatal phenotypes and computational resources have an enormous potential to improve diagnostics and translational research. The Human Phenotype Ontology (HPO) has been widely used to support diagnostics and translational research in human genetics. To better support prenatal usage, the HPO consortium conducted a series of workshops with a group of domain experts in a variety of medical specialties, diagnostic techniques, as well as diseases and phenotypes related to prenatal medicine, including perinatal pathology, musculoskeletal anomalies, neurology, medical genetics, hydrops fetalis, craniofacial malformations, cardiology, neonatal-perinatal medicine, fetal medicine, placental pathology, prenatal imaging, and bioinformatics. We expanded the representation of prenatal phenotypes in HPO by adding 95 new phenotype terms under the Abnormality of prenatal development or birth (HP:0001197) grouping term, and revised definitions, synonyms, and disease annotations for most of the 152 terms that existed before the beginning of this effort. The expansion of prenatal phenotypes in HPO will support phenotype-driven prenatal exome and genome sequencing for precision genetic diagnostics of rare diseases to support prenatal care.
Subject(s)
Computational Biology , Placenta , Infant, Newborn , Humans , Female , Pregnancy , Computational Biology/methods , Phenotype , Rare Diseases , Exome SequencingABSTRACT
BACKGROUND: Due to the limitations of the current routine diagnostic methods, low-level somatic mosaicism with variant allele fraction (VAF) < 10% is often undetected in clinical settings. To date, only a few studies have attempted to analyze tissue distribution of low-level parental mosaicism in a large clinical exome sequencing (ES) cohort. METHODS: Using a customized bioinformatics pipeline, we analyzed apparent de novo single-nucleotide variants or indels identified in the affected probands in ES trio data at Baylor Genetics clinical laboratories. Clinically relevant variants with VAFs between 30 and 70% in probands and lower than 10% in one parent were studied. DNA samples extracted from saliva, buccal cells, redrawn peripheral blood, urine, hair follicles, and nail, representing all three germ layers, were tested using PCR amplicon next-generation sequencing (amplicon NGS) and droplet digital PCR (ddPCR). RESULTS: In a cohort of 592 clinical ES trios, we found 61 trios, each with one parent suspected of low-level mosaicism. In 21 parents, the variants were validated using amplicon NGS and seven of them by ddPCR in peripheral blood DNA samples. The parental VAFs in blood samples varied between 0.08 and 9%. The distribution of VAFs in additional tissues ranged from 0.03% in hair follicles to 9% in re-drawn peripheral blood. CONCLUSIONS: Our study illustrates the importance of analyzing ES data using sensitive computational and molecular methods for low-level parental somatic mosaicism for clinically relevant variants previously diagnosed in routine clinical diagnostics as apparent de novo.
Subject(s)
Exome , Mosaicism , Exome/genetics , High-Throughput Nucleotide Sequencing/methods , Humans , Mouth Mucosa , Parents , Exome SequencingABSTRACT
The disease burden of de novo mutations (DNMs) has been evidenced only recently when the common application of next-generation sequencing technologies enabled their reliable and affordable detection through family-based clinical exome or genome sequencing. Implementation of exome sequencing into prenatal diagnostics revealed that up to 63% of pathogenic or likely pathogenic variants associated with fetal structural anomalies are apparently de novo, primarily for autosomal dominant disorders. Apparent DNMs have been considered to primarily occur as germline or zygotic events, with consequently negligible recurrence risks. However, there is now evidence that a considerable proportion of them are in fact inherited from a parent mosaic for the variant. Here, we review the burden of DNMs in prenatal diagnostics and the influence of parental mosaicism on the interpretation of apparent DNMs and discuss the challenges with detecting and quantifying parental mosaicism and its effect on recurrence risk. We also describe new bioinformatic and technological tools developed to assess mosaicism and discuss how they improve the accuracy of reproductive risk counseling when parental mosaicism is detected.
Subject(s)
Mosaicism , Ultrasonography, Prenatal , Counseling , Female , Humans , Mutation , Parents , Pregnancy , Pregnancy Trimester, FirstABSTRACT
RESEARCH QUESTION: Is physical activity after embryo transfer, as assessed by a smart band activity tracker, associated with decreased pregnancy rates? DESIGN: Prospective observational cohort study comprising infertile women aged < 38 years, who had undergone fewer than three previous embryo transfers, achieved a good ovarian response and were undergoing frozen-thawed embryo transfer in a tertiary-referral centre. A validated smart band activity tracker was used to assess physical activity level immediately after the embryo transfer and until the pregnancy test. No specific recommendations were given to participants on level or intensity of physical activity. Physicians and patients were blinded to the data stored in the pedometer. Primary outcome was ongoing pregnancy rate. RESULTS: Fifty women met the inclusion criteria. Ongoing pregnancy rate was 30%. In a pooled analysis, participants walked significantly fewer steps per day on the day of embryo transfer compared with the first 2 days after embryo transfer (4075, interquatile range [IQR] 2932-5592 versus 5204, IQR4203-8584, Pâ¯=â¯0.01). No significant difference was observed between pregnant women and non-pregnant women in the median steps per day after embryo transfer until serum beta-HCG was measured (7569, IQR 6008-10884 versus 6572.5, IQR 5299-8786, Pâ¯=â¯0.43). No significant difference was observed in the median number of steps on the day of embryo transfer or the first 2 days after embryo transfer between pregnant and non-pregnant women. CONCLUSIONS: A quantitative objective assessment of the association between physical activity and pregnancy rates after frozen-thawed embryo transfer was conducted. Ambulation after embryo transfer has no adverse effect on pregnancy rates and, therefore, women should resume regular activity immediately after embryo transfer.
Subject(s)
Embryo Transfer/statistics & numerical data , Exercise , Pregnancy Rate , Actigraphy , Adult , Female , Humans , Pregnancy , Prospective StudiesABSTRACT
Investigators have long been interested in the natural phenomenon of fetal and placental cell trafficking into the maternal circulation. The scarcity of these circulating cells makes their detection and isolation technically challenging. However, as a DNA source of fetal origin not mixed with maternal DNA, they have the potential of considerable benefit over circulating cell-free DNA-based noninvasive prenatal genetic testing (NIPT). Endocervical trophoblasts, which are less rare but more challenging to recover are also being investigated as an approach for cell-based NIPT. We review published studies from around the world describing both forms of cell-based NIPT and highlight the different approaches' advantages and drawbacks. We also offer guidance for developing a sound cell-based NIPT protocol.
Subject(s)
Noninvasive Prenatal Testing/methods , Cells/microbiology , Female , Humans , Noninvasive Prenatal Testing/instrumentation , Noninvasive Prenatal Testing/trends , Placenta/cytology , Placenta/microbiology , PregnancyABSTRACT
INTRODUCTION: Pre-gestational diabetes mellitus (PGDM) is a major risk factor for fetal overgrowth. Interestingly, even in relatively well controlled PGDM women, as determined by average glucose indices such HbA1c, there is an increased rate of LGA (large for gestational age). Glucose variability (GV) has emerged as an important independent risk factor for several diabetes complications. The aim of this study was to determine the relationship between maternal GV indices and neonatal birth percentile. METHODS: This was a historical cohort study that included all consecutive PGDM women monitored in a single tertiary care center. Clinical and demographic variables, as well as data regarding glucose control, were prospectively recorded. Mean, standard deviation (SD) and coefficient of variance (CV) of glucose values were calculated. Pearson correlations coefficient was used to determine the correlation between glucose indices and birth percentile. The analysis was repeated after adjustment for several confounders. RESULTS: Mean birthweight and birthweight percentile were 3212 ± 532 g and 66.9%, respectively. There was a statistically significant correlation between birthweight percentile and maternal glucose SD (ß = 0.28, p = .002) and maternal glucose CV (ß = 0.21, p = .019). There was no significant correlation between birthweight percentile and mean glucose values. The association between the maternal glucose SD and birthweight percentile remained statistically significant after adjustment for maternal age, pre-pregnancy BMI and duration of diabetes. CONCLUSION: There is an association between maternal glucose variability indices (SD and CV) during pregnancy and neonatal birth percentile. Larger studies are needed to confirm these results.
Subject(s)
Birth Weight , Blood Glucose , Pregnancy in Diabetics/blood , Adult , Cohort Studies , Female , Humans , Infant, Newborn , PregnancyABSTRACT
RESEARCH QUESTION: Does fetal reduction of triplet pregnancies to singleton result in superior obstetric and neonatal outcomes compared with triplets reduced to twins? DESIGN: A historical cohort study including 285 trichorionic and dichorionic triplet pregnancies that underwent abdominal fetal reduction at 11-14 weeks in a single tertiary referral centre. The study population comprised two groups: reduction to twins (nâ¯=â¯223) and singletons (nâ¯=â¯62). Main outcome measures were rates of pregnancy complications, preterm delivery and neonatal outcomes. Non-parametric statistical methods were employed. RESULTS: Triplet pregnancies reduced to twins delivered earlier (36 versus 39 weeks, P < 0.001) with higher prevalence of Caesarean section (71.1% versus 32.2%, P < 0.001) compared with triplets reduced to singletons. Preterm delivery rates were significantly higher in twins compared with singletons prior to 37 weeks (56.9% versus 13.6%, P < 0.001), 34 weeks (20.2% versus 3.4%, Pâ¯=â¯0.002) and 32 weeks (9.6% versus 0%, Pâ¯=â¯0.01). No significant difference was found in the rate of pregnancy loss before 24 weeks (1.3% in twins versus 4.8% in singletons, Pâ¯=â¯0.12) or in the rate of intrauterine fetal death after 24 weeks (0.4% versus 0%, Pâ¯=â¯1.0). Both groups had comparable obstetrical complications and neonatal outcomes, except for higher rates of neonatal intensive care unit admission in twins (31.9% versus 6.8%, P < 0.001). CONCLUSIONS: Reduction of triplets to singletons rather than twins resulted in superior obstetric outcomes without increasing the procedure-related complications. However, because the rate of extreme prematurity in pregnancies reduced to twins was low, the overall outcome of those pregnancies was favourable. Therefore, the option of reduction to singletons should be considered in cases where the risk of prematurity seems exceptionally high.
Subject(s)
Birth Weight/physiology , Pregnancy Reduction, Multifetal/methods , Pregnancy, Triplet , Pregnancy, Twin , Cesarean Section , Female , Gestational Age , Humans , Infant, Newborn , Male , Pregnancy , Pregnancy OutcomeABSTRACT
OBJECTIVES: The aim of this study was to evaluate the role of fetal magnetic resonance imaging (MRI) as a complement to ultrasound (US) in the prenatal diagnosis of craniofacial anomalies. METHODS: A historical cohort study including all pregnant women who were referred for fetal MRI because of antenatal diagnosis of craniofacial anomalies on screening US. Prenatal diagnostic US, MRI, and postnatal diagnosis were compared for consistencies and discrepancies. RESULTS: Forty-five pregnant women with 73 suspected fetal craniofacial anomalies diagnosed by US underwent MRI. In 40 out of 73 anomalies (54.8%), US and MRI findings were in complete agreement with postnatal diagnoses. MRI correctly ruled out the diagnosis of 24 anomalies suspected on US and diagnosed four additional pathologies that were not demonstrated by US. Out of the 85 anomalies (suspected by imaging or confirmed postnatally), confident diagnosis could be made by MRI in 68 anomalies (80%), not diagnosed in 10 (11.8%), and over-diagnosed in seven (8.2%). By US, confident diagnosis could be made in 44 anomalies (51.8%), not diagnosed in 11 (12.9%), and over-diagnosed in 30 (35.3%). CONCLUSION: MRI is valuable in the antenatal evaluation of fetal craniofacial anomalies and may be useful as an adjunct to US in the prenatal work-up of craniofacial anomalies.
Subject(s)
Craniofacial Abnormalities/diagnostic imaging , Magnetic Resonance Imaging/methods , Ultrasonography, Prenatal/methods , Adult , Female , Humans , Infant, Newborn , Male , Pregnancy , Prenatal Diagnosis , Sensitivity and SpecificityABSTRACT
The aim of this study was to determine the association between glucose control indices of parturient with type 1 diabetes (T1DM), treated with an insulin pump and utilizing continuous glucose monitoring (CGM), and clinically significant neonatal hypoglycemia. This was a retrospective cohort study which included 37 pregnant women with T1DM. All women were followed at a single tertiary center and had available CGM data. The association between maternal glucose indices before delivery and the risk for neonatal hypoglycemia requiring IV glucose (clinically significant hypoglycemia) was assessed using logistic regression. Mothers to neonates that experienced clinically significant hypoglycemia had a higher glucose standard deviation (SD) before delivery than did mothers to neonates who did not (25.5 ± 13 mg/dL vs. 14.7 ± 6.7 mg/dl respectively; p = .008). This association persisted after adjustment for maternal age, maternal pregestational body mass index (BMI), gestational age at delivery, neonatal birth weight, large for gestational age (LGA) and gender. This study demonstrates an association between high maternal glucose standard deviation before delivery and the risk for clinically significant neonatal hypoglycemia. Larger studies are needed to confirm these results and further explore the role of intrapartum glucose variability in the prediction and prevention of significant neonatal hypoglycemia.
Subject(s)
Blood Glucose/analysis , Diabetes Mellitus, Type 1/blood , Health Status Indicators , Hypoglycemia/diagnosis , Infant, Newborn, Diseases/diagnosis , Pregnancy in Diabetics/blood , Adult , Blood Glucose/metabolism , Blood Glucose Self-Monitoring/standards , Cohort Studies , Diabetes Mellitus, Type 1/diagnosis , Female , Gestational Age , Glycated Hemoglobin/analysis , Glycated Hemoglobin/metabolism , Glycemic Control/standards , Humans , Hypoglycemia/blood , Hypoglycemia/congenital , Infant, Newborn , Infant, Newborn, Diseases/blood , Male , Predictive Value of Tests , Pregnancy , Pregnancy Outcome , Pregnancy in Diabetics/diagnosis , Prognosis , Retrospective Studies , Young AdultABSTRACT
BACKGROUND: Pregestational diabetes mellitus (PGDM) carries a significantly elevated risk of adverse maternal and fetal outcomes. There is evidence that certain interventions reduce the risk for adverse outcomes. Studies have shown that a multi-disciplinary approach improves pregnancy outcomes in women with PGDM. OBJECTIVES: To determine pregnancy outcomes in women with PGDM using a multi-disciplinary approach. METHODS: We retrospectively reviewed consecutive women with pregestational type 1 and type 2 diabetes who were monitored at a high-risk pregnancy clinic at the Sheba Medical Center. Clinical data were obtained from the medical records. All data related to maternal glucose control and insulin pump function were prospectively recorded on Medtronic CareLink® pro software (Medtronic MiniMed, Northridge, CA). RESULTS: This study comprised 121 neonates from 116 pregnancies of 94 women. In 83% of the pregnancies continuous glucose monitoring (CGM) sensors were applied during a part or all of the pregnancy. Pregnancy outcomes among women who were followed by a multi-disciplinary team before and during pregnancy, and during labor and puerperium resulted in better glucose control (hemoglobin A1c 6.4% vs. 7.8%), lower risk for pregnancy induced hypertension/preeclampsia (7.7% vs. 15.6%), lower birth weight (3212 g vs. 3684 g), and lower rate of large size for gestational age and macrosomia (23.1% vs. 54.2% and 3.3% vs. 28.4%, respectively), compared to data from European cohorts. CONCLUSIONS: The multi-disciplinary approach for treating women with PGDM practiced in the high-risk pregnancy clinic at the Sheba Medical Center resulted in lower rates of macrosomia, LGA, and pregnancy induced hypertension compared to rates reported in the literature.
Subject(s)
Diabetes Mellitus/therapy , Pregnancy Complications/therapy , Prenatal Care/methods , Adult , Blood Glucose , Female , Fetal Macrosomia/prevention & control , Humans , Hypertension/prevention & control , Infant, Low Birth Weight , Infant, Newborn , Insulin/therapeutic use , Israel , Pre-Eclampsia/prevention & control , Pregnancy , Prospective Studies , Retrospective StudiesABSTRACT
OBJECTIVE: This study aims to assess the utility of a detailed early fetal anatomy scan prior to karyotyping in the management of pregnancies with an increased nuchal translucency (NT). METHODS: The study included fetuses with NT above the 99th centile. These women were offered the option of an early detailed fetal anatomy scan prior to genetic evaluation. The presence or absence of major sonographic findings was analyzed for its predictive value for fetal aneuploidy. RESULTS: An increased NT >99th centile was detected in 43 fetuses (1.8%). Mean NT was 4.5 mm (range 3.4-9.0), and gestational age at the early fetal anatomy survey was 12.4 weeks (12-13.6). Major sonographic findings were present in 30 fetuses (69.8%); 24 of them underwent karyotyping, and it was abnormal in 14. Among the 13 fetuses without major sonographic findings, 12 had normal karyotype results, and 1 had aneuploidy, yielding a positive predictive value of 58.3% of early fetal anatomy scan for abnormal karyotype results. Multivariate logistic regression analysis showed that the presence of major sonographic findings was as an independent predictor of fetal aneuploidy (adjusted odds ratio 8.15). CONCLUSION: A detailed early anatomy scan upon detection of increased NT has an important value in the prediction of fetal aneuploidy. © 2016 John Wiley & Sons, Ltd.