Chromosome 15q overgrowth syndrome: prenatal diagnosis, molecular cytogenetic characterization, and perinatal findings in a fetus with dup(15)(q26.2q26.3)

ObjectiveTo present molecular cytogenetic characterization of a prenatally detected duplication of 15q26.2 → q26.3 in a fetus with overgrowth.Case ReportA 34-year-old para 0 woman underwent amniocentesis at 18 weeks of gestation because of advanced maternal age. Amniocentesis revealed a derivative chromosome 15, or der(15), with additional material at the end of the long arm of one chromosome 15. Parental karyotypes were normal. Fetal overgrowth was first noted at 21 weeks of gestation. Repeated amniocentesis was performed at 22 weeks of gestation. Array comparative genomic hybridization revealed a 4.71-Mb duplication from 15q26.2 to 15q26.3 encompassing the IGF1R gene. Fluorescence in situ hybridization analysis using the bacterial artificial chromosome clone probes specific for 15q26.2-q26.3 and the subtelomeric region of 15q showed a direct duplication and no terminal deletion in the der(15). Polymorphic DNA marker analysis determined a paternal origin of the duplication of 15q. Level II ultrasound at 23 weeks of gestation revealed a fetal biometry equivalent to 26 weeks. The pregnancy was subsequently terminated, and a 1062-g (>99^th centile) malformed fetus was delivered at 24 weeks of gestation with craniofacial dysmorphism, craniosynostosis, and overgrowth.ConclusionThe present case provides evidence for prenatal overgrowth, craniosynostosis, and characteristic facial dysmorphism in association with a duplication of 15q26.2 → q26.3 and a duplication of the IGF1R gene. Prenatal diagnosis of fetal overgrowth should include a differential diagnosis of the chromosome 15q overgrowth syndrome.     

Progressive development of sonographic features in prenatal diagnosis of Apert syndrome--case report and literature review

Apert syndrome is characterized by craniosynostosis, midfacial malformations and symmetrical syndactyly of the hands and feet. We report a case of prenatal sonographic diagnosis of Apert syndrome. Mild ventriculomegaly with normal head shape observed at 22 weeks gestation, followed by colpocephaly at 25 weeks gestation and bilateral syndactyly and subsequent craniosynostosis at 28 weeks, led to the prenatal diagnosis of Apert syndrome. The diagnosis was confirmed by physical examination and molecular study after birth. Additionally the authors present the review of literature on prenatal sonographic diagnosis of Apert syndrome.     

Prenatal diagnosis of Simpson–Golabi–Behmel syndrome type 1 with an 814 kb Xq26.2 deletion with the initial presentation of a thick nuchal fold

ObjectiveSimpson–Golabi–Behmel syndrome type 1 (SGBS1) is a rare X-linked recessive disorder characterized by overgrowth and multiple anomalies. Most clinical diagnoses of SGBS1 are made postnatally. We present the case of a pregnant woman in whom the fetus presented with a thick nuchal fold 5.6 mm at 15 weeks of gestation, leading to the prenatal diagnosis of SGBS1 with Xq26.2 (133408101–134221889) deletion.Case reportWe report the case of a 34-year-old pregnant woman with the initial presentation of fetal thick nuchal fold 5.6 mm at 15 weeks of gestation. Amniocentesis of the fetal karyotype revealed a normal 46, XY, and single nucleotide polymorphism array showed Xq26.2 (133408101–134221889) deletion. Prenatal ultrasound at 21 weeks of gestation revealed a thick nuchal fold, hepatomegaly, nephromegaly, congenital diaphragmatic hernia, hypospadias, and polyhydramnios. Fetal magnetic resonance imaging revealed hepatomegaly, nephromegaly, congenital diaphragmatic hernia, and right lung hypoplasia. The woman had her pregnancy terminated at 24 weeks of gestation. The proband had a general appearance of low-set ears, hypertelorism, a large tongue, and hypospadias and some unique findings on autopsy, including hepatomegaly, right hiatal hernia, liver extensive extramedullary hematopoiesis, kidney marked congestion, and focal hemorrhage.DiscussionThe main prenatal ultrasound findings that alert clinical doctors about the possible diagnosis of SGBS1 included macrosomia, polyhydramnios, organomegaly, renal malformations, congenital diaphragmatic hernia, and cardiac anomalies. Our case underscores the importance of fetal karyotyping combined with single nucleotide polymorphism array when a thick nuchal fold is found. Genetic counseling is essential in SGBS1, and prenatal testing or preimplantation testing for subsequent pregnancies is necessary to identify possible pathogenic variants.     

Midtrimester diagnosis of endocardial fibroelastosis and atrial septal defect: a case report

We present a case report of endocardial fibroelastosis combined with atrial septal defect in which the diagnosis was strongly suspected at 25 weeks of gestation. To our knowledge the only previous report of prenatal diagnosis of endocardial fibroelastosis was of one made at 36 weeks of gestation.     

Detection of hypermethylation at H19DMR at amniocentesis in a fetus with overgrowth,distended abdomen and Beckwith-Wiedemann syndrome

ObjectiveWe present detection of hypermethylation at H19 differentially methylated region (DMR) at amniocentesis in a fetus with overgrowth, distended abdomen and Beckwith-Wiedemann syndrome (BWS).Case reportA 31-year-old, gravida 2, para 1, woman was referred for genetic counseling at 22 weeks of gestation because of fetal overgrowth with fetal biometry equivalent to 24 weeks of gestation and a distended abdomen with an abdominal circumference equivalent to 26 weeks of gestation. She did not undergo any assisted reproductive technology during this pregnancy. Amniocentesis was performed at 23 weeks of gestation. Conventional cytogenetic analysis revealed a karyotype of 46,XX. Array comparative genomic hybridization analysis on the DNA extracted from uncultured amniocytes revealed no genomic imbalance. Methylation analysis on the DNA extracted from amniocytes revealed hypermethylation at H19DMR [imprinting center 1 (IC1)] and normal methylation at KvDMR1 (IC2). The methylation test confirmed the diagnosis of BWS in the fetus. The parents decided to continue the pregnancy. At 36 weeks of gestation, a 4000-g female baby was delivered with macroglossia, ear tags and creases, and an enlarged liver, consistent with the phenotype of BWS.ConclusionPrenatal diagnosis of fetal overgrowth should include a differential diagnosis of BWS, and methylation analysis of H19DMR (IC1) and KvDMR1 (IC2) is useful under such a circumstance.     

Intrauterine intussusception presenting as fetal ascites at prenatal ultrasonography

Intrauterine intussusception, an uncommon cause of bowel obstruction, has rarely been detected by prenatal ultrasonography. We report two cases of intrauterine intussusception after gestation, which presented as isolated fetal ascites at 30 weeks of gestation by ultrasonography. In case 1, on the follow-up ultrasonography at 32 weeks of gestation, the previously observed ascites had disappeared, whereas the echogenicity of the bowel was increased without any sign of dilation, suggesting the presence of meconium peritonitis. The fetus was delivered at 39 weeks. In case 2, however, the amount of fetal ascites became increased, and the fetus was delivered at 34 weeks of gestation. After delivery, both infants were surgically explored with resection of the ileum with end-to-end anastomosis because of intrauterine intussusception and ileal atresia. From the experience of these cases, we suggest that the ultrasonographic finding of isolated or transient fetal ascites might contribute to the early diagnosis and management of intrauterine intussusception.     

Prenatal diagnosis and postnatal management of diffuse congenital hyperinsulinism: a case report

We present the first case of the prenatal diagnosis of congenital hyperinsulinism based on the genetic analysis of known family mutations in the SUR1 gene. An amniocentesis was performed at 16 weeks gestation at which time two mutations in the SUR1 gene were identified consistent with the diagnosis of diffuse hyperinsulinism. The mother was transported to our facility and underwent an elective caesarian section at 38 weeks gestation. The diagnosis was confirmed and treatment was initiated within the first minutes of life. After a short course of failed medical management, the patient underwent a 98% pancreatectomy with subsequent good glycemic control. This case highlights the benefits of the timely in utero diagnosis of hyperinsulinism by mutational analysis.     

Congenital diaphragmatic hernia. Two cases with early prenatal diagnosis and increased nuchal translucency

The early ultrasound prenatal diagnosis of congenital diaphragmatic hernia is uncommon and suggests a poor outcome. We report 2 cases diagnosed at 10 and 12 weeks' gestation, with increased fetal nuchal translucency thickness (4 and 11 mm) and associated abnormalities (complex heart defect in one and many malformations in the other, including duodenal atresia and asplenia). In 1 case, the baby was delivered vaginally at 36 weeks, but neonatal death occurred; the pregnancy was terminated at 15 weeks in the second case.     

Fetal meconium peritonitis in single and twin pregnancy. Two cases report

We present two cases of fetal meconium peritonitis in a single and twin pregnancy, respectively. The first case diagnosis was made at 30 weeks and was confirmed after delivery of the twins by cesarean section at 37 weeks. The second case diagnosis was made at 31 week and was confirmed at 37 weeks. Meconium peritonitis is a rare prenatal complication that results from intrauterine perforation of small bowel with spillage of sterile meconium into peritoneal cavity. We now report two cases of meconium peritonitis diagnosed at 30 and 31 weeks gestation. Received: 20 March 2001 / Accepted: 13 June 2001     

Radiographic and genetic diagnosis of sporadic hypochondroplasia early in the neonatal period

Hypochondroplasia is an autosomal dominant skeletal dysplasia expressing postnatal onset of short stature with mild rhizomelic shortening of the limbs. This manifestation leads to restricted prenatal diagnosis of the disorder. We report here on a sporadic case of a hypochondroplastic baby, whose prenatal sonographic measurements were serially recorded from 19 weeks of gestation. Mild shortening of the limbs became manifest after 26 weeks of gestation. Biparietal diameter was within the normal range throughout gestation. Both parents were of average stature. A tentative diagnosis of a nonlethal short-limb skeletal dysplasia was made. At birth, the clinical manifestations of the neonate were not characteristic, but the radiographic features raised the possibility of hypochondroplasia. Molecular analyses revealed a C to G mutation at nucleotide 1659 of the fibroblast growth factor receptor 3 (FGFR3) gene, a common mutation in hypochondroplasia.     

Prenatal diagnosis of lissencephaly

We report two cases of prenatal detection of lissencephaly by high-resolution ultrasound. The first case studied was referred for high-risk obstetrical management and serial antenatal ultrasounds because of a family history of lissencephaly in an unresolved chromosomal abnormality. Diagnosis of a smooth gyral pattern consistent with lissencephaly was made at 32 weeks' gestation. The second case was referred for prenatal ultrasound because of a size versus dates discrepancy. The ultrasound examination showed a smooth gyral pattern at 31.5 weeks. In light of this ultrasound finding, a fetal blood sample was obtained and a chromosomal abnormality reported, confirming the diagnosis. To our knowledge, these cases represent the first report of the sonographic prenatal diagnosis of cerebral agyria or lissencephaly.     

First-trimester prenatal diagnosis of Roberts syndrome.

We present a case of prenatal detection of premature centromere separation on chorionic villi sampled at 8 weeks' gestation from a woman at risk of recurrence of Roberts syndrome. The same cytogenetic characteristic was confirmed on amniocytes at 14 weeks when ultrasound examination showed morphological anomalies of the fetus. To our knowledge, this is the first report of early prenatal diagnosis of Roberts syndrome.     

Antenatal sonographic diagnosis of arthrogryposis multiplex congenita

Arthrogryposis Multiplex Congenita (AMC) was suspected on ultrasound examination of a fetus at 30.5 weeks of gestation. The criteria for establishing this prenatal diagnosis as well as the importance of establishing the diagnosis at any gestational age are discussed. The diagnosis of AMC was confirmed at birth in this case.     

First trimester diagnosis of dicephalus conjoined twins

Dicephalus twinning is an extremely rare type of conjoined twins. Early prenatal diagnosis of this condition is important to provide an opportunity for pregnancy termination. We present such a case, which was diagnosed by ultrasound examination at 12 weeks of gestation. The ultrasonographic criteria are discussed together with implications for management.     

Prenatal diagnosis of isolated anorectal atresia with colonic perforation.

We report here a case of prenatal diagnosis of isolated anorectal atresia with intrauterine colonic perforation at 34 weeks of gestation, characterized by the presence of a bilobed cystic pelvic mass with a V-shape appearance separated from the bladder with changing features during observation. Mild ascites was also visualized. Other structures were normal on detailed ultrasound. The patient had spontaneously delivered a male infant weighing 2,100 g at 34 weeks of gestation. The infant died one day after birth, before surgical correction secondary to respiratory distress syndrome. Autopsy revealed isolated anorectal atresia, and high (supraelevator) lesions. In conclusion, the findings of bilobed cystic pelvic mass with a V-shape were useful to diagnose anorectal atresia in this case. Prenatal ultrasound can facilitate early diagnosis and treatment.     

First trimester increased nuchal translucency associated with fetal achondroplasia

A 30-year-old woman, gravida 2, para 1, was referred for nuchal translucency, free beta-human chorionic gonadotropin (beta-hCG), and pregnancy-associated plasma protein A (PAPP-A) screening at 12 weeks gestation. The nuchal translucency was increased to 3.8 mm, resulting in a post-test result of 1:15 risk for Down syndrome by a combination of maternal age plus nuchal translucency, and 1:5 by a combination of maternal age plus nuchal translucency plus free beta-hCG plus PAPP-A. The patient underwent uncomplicated chorionic villus sampling that demonstrated a normal 46,XY fetus. The patient was then followed-up weekly by ultrasound. At 18 weeks gestation, generalized features of rhizomelic micromelia together with macrocrania and narrow thorax were seen. All fetal long bones were less than 2 standard deviations from the mean value. At that time, DNA analysis was performed on stored villi and a G380R mutation in the locus gene encoding for the fibroblast growth factor receptor 3 on chromosome 4p16.3 was found, leading to a prenatal diagnosis of achondroplasia. The couple opted for termination of pregnancy after counseling. Postmortem X-ray was done and confirmed the ultrasound diagnosis of achondroplasia. This is the second known case of increased nuchal translucency in the first trimester associated with prenatal confirmed diagnosis of fetal osteochondrodysplasia.     

X pentasomy in an intracytoplasmic sperm injection pregnancy detected by nuchal translucency testing

Althoughmaternally derived X pentasomy following intracytoplasmic sperm injection (ICSI) is rare, prenatal detection of a case offers insight into etiology and diagnosis. A 29-year-old gravida 1 whose pregnancy resulted from ICSI was referred for ultrasound screening at 11 weeks' gestation. Nuchal translucency thickness was 3.2 mm, and the fetal nasal bone was absent. Subsequent evaluation revealed karyotype 49,XXXXX. DNA microsatellite analysis showed the extra X chromosomes were maternal in origin. Termination of pregnancy was performed at 15 weeks. Because of the increased risk of sex chromosomal abnormalities in ICSI pregnancies, patients should be counseled prior to fertilization and standard prenatal care should include nuchal translucency measurement and any other elements necessary for indicated pregnancies to obtain a diagnosis.     

Prenatal diagnosis of mucolipidosis type II on first-trimester amniotic fluid

We investigated the possibility of prenatal diagnosis of mucolipidosis type II (ML II) by lysosomal enzyme determination on amniotic fluid obtained at 11 weeks of gestation in three pregnancies at risk. Diagnosis of ML II was made in one case on the basis of increased levels of five lysosomal enzymes tested. The diagnosis was confirmed on cultured chorionic cells, their cultured medium, 17-week amniotic fluid, and fetal plasma obtained for confirmation prior to the termination of pregnancy.     

Prenatal diagnosis of congenital hypophosphatasia in a consanguineous Bedouin couple. A case report

BACKGROUND: Hypophosphatasia is a rare autosomal recessive metabolic disorder characterized by low serum and tissue alkaline phosphatase activity, increased urinary excretion of phosphoethanolamine and ricketslike changes in the bone. CASE: We present a case of prenatal diagnosis of congenital hypophosphatasia in a consanguineous Bedouin couple. The case was diagnosed at 24.5 weeks of gestation. Sonographic evaluation revealed a fetus with short and deformed bones and a hypoechogenic skull. Based on the sonographic findings and the obstetric history of the couple, hypophosphatasia was diagnosed. The parents opted for pregnancy termination. Feticide was accomplished uneventfully. Laboratory findings confirmed the diagnosis. CONCLUSION: This couple was prone to this metabolic disorder due to their consanguineous marriage and previous affected fetus. Early-first-trimester prenatal diagnosis by first-trimester chorionic villus sampling or second-trimester measuring of alkaline phosphatase activity in the amniotic fluid is required to exclude this lethal disease in subsequent pregnancies.