Prenatal diagnosis of the Beckwith-Wiedemann syndrome

Chromosome 11 segmental paternal isodisomy in amniocytes from two fetuses with omphalocoele: new highlights on phenotype-genotype correlations in Beckwith-Wiedemann syndrome

BACKGROUND

The phenotypic variability in Beckwith-Wiedemann syndrome (BWS) reflects the genetic heterogeneity of the mechanism which by default leads to the deregulation of genes located at 11p15.5. Genotype-phenotype correlation studies have demonstrated an association between omphalocoele and CDKN1C/p57 mutations or hypermethylation. Paternal uniparental disomy 11 (pUPD11) has been described only in the mosaic condition with both uniparental and biparental cell lines, and no association with omphalocoele has been pointed out.

METHODS

Two cases are presented here, in which a paternal segmental UPD11 was detected by molecular investigation of amniotic fluid cell cultures after the presence of apparently isolated omphalocoele was revealed in the fetuses by ultrasound scan. Further studies were performed on additional autoptic feto-placental tissues to characterise the distribution of the uniparental cell line and to unmask any biparental lineage in order to document in more detail the as yet unreported association between omphalocoele and pUPD11.

RESULTS

Results on the UPD distribution profile showed that the abdominal organs have a predominant uniparental constitution. This condition could mimic the effect of CDKN1C/p57 inactivation, causing the omphalocoele.

CONCLUSION

New genotype-phenotype correlations emerge from the investigated cases, suggesting that molecular analysis be extended to all cases with fetal omphalocoele in order to establish the incidence of pUPD11 in complete BWS and in monosymptomatic/mild forms.

Beckwith-Wiedemann Syndrome Presenting with an Elevated Triple Screen in the Second Trimester of Pregnancy

BACKGROUND

Beckwith-Wiedemann syndrome (BWS) is a distinct clinical syndrome with unique features, generally diagnosed postnatally.

CASE

A 26-year-old patient, gravida 4, para 3-0-0-3, was noted to have an abnormal maternal serum screen. Amniocentesis with imaging studies were remarkable only for a two-vessel umbilical cord and prominent maternal ovaries. The patient developed HELLP syndrome at 28 weeks and delivered a viable female infant with distinct clinical features. The diagnosis of BWS was confirmed by hypermethylation of the H19 gene on chromosome 11p15.5.

CONCLUSION

This case describes a novel presentation of BWS and underscores the diagnostic potential of routine prenatal screens.

Factors associated with preterm delivery in mothers of children with Beckwith-Wiedemann syndrome: a case cohort study from the BWS registry

Pregnancy that results in a child with Beckwith-Wiedemann syndrome (BWS) is associated with preterm delivery. Based on previous case series, we hypothesized that preterm delivery of a child with BWS was due to known risk factors for preterm delivery such as polyhydramnios and gestational hypertension. A case cohort study using the BWS Registry at Washington University School of Medicine was undertaken. Cases were pregnancies that resulted in the birth of a child with BWS, controls were pregnancies resulting in the birth of siblings without BWS. Univariate analyses of maternal complications and logistic regression to predict preterm delivery were used. Children with BWS (n = 304) were delivered preterm at a significantly higher rate than their siblings (n = 269) odds ratio 19.1 (95% CI 9.1-40.2). Polyhydramnios, gestational hypertension, and vaginal bleeding also occurred at high rates in the BWS group with odds ratios of 31.6 (95% CI 12.6-79.1), 2.4 (95% CI 1.4-4.1), and 3.9 (95% CI 2.3-6.4), respectively. In a multivariate logistic regression model within the BWS group, polyhydramnios, vaginal bleeding, and gestational hypertension were significant predictors of preterm delivery, odds ratios of 2.9 (95% CI 1.6-5.4), 2.6 (95% CI 1.3-5.0), and 5.3 (2.3-12.0), respectively. However, a significant proportion, 6.5% (18 of 277), of patients in the BWS group delivered preterm without known risk factors. Preterm delivery of a child with BWS is associated with an increased frequency of polyhydramnios, gestational hypertension, and vaginal bleeding in the mother. However, preterm delivery also occurs in the absence of these risk factors.

Prenatal diagnosis of Beckwith-Wiedemann syndrome

OBJECTIVES

The diagnosis of Beckwith-Wiedemann syndrome (BWS) typically is made after birth. To our knowledge, no established guidelines exist for the prenatal diagnosis of this condition. We present two new cases of prenatally diagnosed BWS and propose a diagnostic schema.

METHODS

Published reports obtained from Medline searches were reviewed and combined with our cases.

RESULTS

Our proposed schema of two major criteria (abdominal wall defect, macroglossia, macrosomia) or one major plus two minor criteria (nephromegaly/dysgenesis, adrenal cytomegaly, aneuploidy/abnormal loci, polyhydramnios) fits all published reports of prenatally diagnosed BWS.

CONCLUSION

The prenatal diagnosis of BWS can be reliably made by applying our proposed guidelines. This schema allows for uniform fetal diagnosis of the syndrome and helps prepare for prenatal counseling and peri- and post-natal management strategies.

Early detection of fetal structural abnormalities

Most published data on the detection of fetal anomalies at 11-14 weeks are from specialized centres with considerable experience in fetal anomaly scanning. However, there is still limited information on the feasibility and limitations of the screening of these anomalies compared with the now classical mid-gestation screening. This review indicates that overall, the detection rate of fetal anomalies at 11-14 weeks is 44% compared with 74% by the mid-pregnancy scan. Major abnormalities of the fetal head, abdominal wall and urinary tract, and of the umbilical cord and placenta, can be reliably detected at 10-11 weeks of gestation. Detection of other anomalies such as spina bifida, diaphragmatic hernia or heart defects is limited before 13 weeks of gestation. So far it cannot be stated that routine first trimester screening can be used on a large scale to evaluate the fetal spine and heart in the general population. In particular, in screening for congenital heart defects, the ability to perform a full cardiac examination increases from 20% at 11 weeks to 92% at 13 weeks. The early prenatal diagnosis of these anomalies may be improved by screening at 13-14 weeks rather than during the first trimester.

Wiedemann-Beckwith syndrome: further prenatal characterization of the condition

We describe three unrelated cases of Wiedemann-Beckwith syndrome (WBS). Two of them were diagnosed postnatally while the third was detected during pregnancy that resulted in elective termination. Amniotic karyotypes were normal in all. PCR amplification of polymorphic loci mapping to 11p15.5 region documented partial trisomy of 11p15.5 due to paternal translocation in one, and segmental and mosaic segmental unipaternal disomy (UPD) in the second and third cases, respectively. Based on findings documented in these cases and the literature, we tabulated the anomalies that might be detected prenatally by ultrasound and that may suggest the syndrome. Constant findings included fetal overgrowth, polyhydramios, enlarged placenta, and specifically a distended abdomen. As most described signs developed after 22 weeks of gestation, a careful follow-up should be carried on until late stages of pregnancy. An amniotic karyotype might not detect subtle chromosomal rearrangements. We therefore recommend utilizing PCR of polymorphic loci on 11p15.5, in addition to conventional cytogenetic analysis of the fetus and both parents to detect possible maternal deletions or inversions, paternal duplications, and UPD that may account for the largest subset of sporadic WBS reaching 25% of cases. An early diagnosis of WBS is important for counseling the parents concerning potential risk for developing embryonic tumors, selection of the mode of delivery due to potential adrenal cysts that might bleed during labor, and prevention of neonatal hypoglycemia.

Prenatal sonographic diagnosis of Beckwith-Wiedemann syndrome in association with a single umbilical artery

Beckwith-Wiedemann syndrome is an inherited disorder most commonly characterized by prenatal or postnatal overgrowth, macroglossia, omphalocele, unusual earlobe creases, and increased risk of neoplasia. Several reported cases of this syndrome have been prenatally diagnosed, but no report has described the occurrence of this syndrome in association with a single umbilical artery. We report a case in which prenatal sonographic examination demonstrated fetal overgrowth, macroglossia, and omphalocele together with a single umbilical artery; our prenatal diagnosis of Beckwith-Wiedemann syndrome was confirmed after birth of the infant. The possibility of this syndrome should be considered when performing a detailed sonographic examination of a fetus with a single umbilical artery.

Beckwith-Wiedemann syndrome and virilizing cortical adrenal tumor in a child

The authors report a case of a virilizing adrenal tumor that developed in a 2-year-old child with Beckwith-Wiedemann syndrome (BWS). He had a fetal diagnosis of omphalocele and a history of neonatal adrenal cysts. The importance of prenatal diagnosis of BWS and postnatal follow-up of tumors is discussed. The differential diagnosis of adrenal pathologies occurring in BWS also is reviewed.

Perlman syndrome--a cause of enlarged, hyperechogenic kidneys

Perlman syndrome is a rare overgrowth syndrome, thought to be inherited in the autosomal recessive fashion. We describe the sonographic features in two cases, and review the literature.

The antenatal diagnosis and management of abdominal wall defects: the northern region experience

One hundred and twenty abdominal wall defects were notified to the Northern Region Fetal Abnormality Survey in the five years 1988 to 1992. Gastroschisis occurred in 56, exomphalos in 43, amnion rupture in 11, ectopia vesicae in seven and ectopia cordis in three. Ultrasound failed to identify gastroschisis in 14 and incorrectly diagnosed exomphalos in eight. There was no associated chromosome abnormality and the survival rate, excluding first trimester loss, was 87%. Ultrasound failed to identify exomphalos in ten and incorrectly diagnosed gastroschisis in two. Another structural abnormality was present in 40% and a chromosome anomaly in 28%. Excluding spontaneous first trimester loss, the survival rate was 34%. Delivery of babies away from the regional paediatric surgical centre did not adversely affect the outcome in gastroschisis or exomphalos although closure was delayed, on average, by 2 h. There was one survivor of 11 fetuses with amnion rupture sequence. Six of the seven babies with ectopia vesicae and two of the three with ectopia cordis survived.

Prenatal Sonogra phic Evaluation of Beckwith-Wiedemann Syndrome

Beckwith-Wiedemann syndrome (BWS) was first described by Beckwith in 1963 and Wiedemann in 1964 as a syndrome of macroglossia, visceromegaly,. omphalocele, gigantism, and neonatal hypoglycemia. Additonal features of the syndrome, which occurs in approximately 1 in every 14,000 births, have been subsequently described. The authors report 2 cases of fetal BWS observed sonographically, and review 16 previously reported cases. Pohydramnios and growth acceleration may occur before 20 weeks, but macrlossia has not been reported before 28.5 weeks. Searching for ear creases in a fetus with suspected BWS may be merited, but visualization of normal ear lobes does not exclude the possibility of BWS.

Evidence for paternal imprinting in familial Beckwith-Wiedemann syndrome

A previously unreported family in which seven members in two generations have Beckwith-Wiedemann syndrome (BWS) is documented. Paternal imprinting of the gene responsible for BWS is involved as the mechanism responsible for the aberrant inheritance pattern in this kindred. A review of published reports showed 27 previously published pedigrees with two or more affected subjects with BWS. Paternal imprinting would explain the non-mendelian inheritance of BWS in all but four kindreds. The latter families are examined in more detail and in only one example is the evidence against imprinting totally unexplained.

Prenatal diagnosis in autosomal dominant Beckwith-Wiedemann syndrome

A 20-year-old woman with Beckwith-Wiedemann syndrome (BWS) was ultrasonographically appraised at intervals during her pregnancy. Unequivocal evidence for a diagnosis of BWS was obtained in the fetus and this was confirmed postnatally. Early ultrasound diagnosis enabled appropriate genetic counselling to be given; neonatal complications, such as hypoglycaemic episodes, were prevented.

Apparent postnatal onset of some manifestations of the Wiedemann-Beckwith syndrome

We report on 2 patients who were apparently normal at birth but later developed characteristics of Wiedemann-Beckwith syndrome (WBS). Both had hypoglycemia neonatally and gradually developed coarse facial changes, umbilical hernia, and macroglossia. Renal sonography done after the macroglossia developed showed large kidneys in both. The placentas were carefully examined in both cases but findings described as typical of WBS were only found in one. The clinical evolution of these infants suggests that some WBS manifestations may have their onset postnatally in some cases. We postulate that the cellular hyperplasia and hypertrophy characteristic of WBS may be caused by persistent rests of embryonal cells that secrete paracrine and/or endocrine growth factors.

Prenatal diagnosis of Wiedemann-Beckwith syndrome

We report the prenatal diagnosis of Wiedemann-Beckwith syndrome in the 28th week of pregnancy in a primigravida. The cause of hospitalization was severe polyhydramnios with premature labour. Sonography revealed macrosomia, nephromegaly, cysts of adrenal glands and a striking macroglossia with opened mouth in all controls. The combination of all these symptoms suggested the prenatal diagnosis of Wiedemann-Beckwith syndrome, which could be confirmed post partum after a normal delivery in the 33rd week of pregnancy. The newborn (2700 g, 48 cm) exhibited typical features of this syndrome as moderate hypoglycemia and polycythemia in addition to the sonographic finding. Pathogenetic aspects and differential diagnosis of macrosomia are discussed.

Wiedemann-Beckwith syndrome

The Wiedemann-Beckwith syndrome (WBS) comprises an accumulation of multiple congenital anomalies. Exomphalos, macroglossia and gigantism are considered the most common manifestations, hence the alternative designation EMG-syndrome. The syndrome carries with it an increased risk of developing specific tumours. One of the more frequent metabolic changes is transient neonatal hypoglycaemia, the result of increased insulin secretion. Inheritance of the syndrome remains uncertain. Most cases are sporadic, but a number of familial cases have been reported. Present evidence suggests that WBS is an autosomal dominant trait with variable expressivity. This review summarizes the abundant literature on the subject and discusses recent molecular genetic developments that may explain the interrelationship between the clinical abnormalities, metabolic disturbances and development of tumours.

Genetic causes of mental handicap and opportunities for prevention

Prior to 1970 nearly one half of severe mental handicap (IQ less than 50) was unexplained and genetic causes were recognized in one third of all patients. In recent years the genetic contribution has risen to 50%, with the decline in importance of environmental causes and the growing recognition of X-linked forms of mental retardation and chromosomal microdeletion syndromes. Recognition of genetic conditions is vital for accurate assessment of recurrence risks and in order, in some instances, to provide specific prenatal diagnosis. With full utilization of existing prenatal screening procedures and a more detailed family history, severe mental handicap due to genetic conditions should be reduced by 30-40%.

Prenatal ultrasound diagnosis of macroglossia in the Wiedemann-Beckwith syndrome

We report the ultrasound prenatal diagnosis at the 30th week of macroglossia in two sibs with the Wiedemann-Beckwith syndrome; the syndrome was also present in their mother. A study of high resolution chromosomes did not show any anomaly.

Wiedemann-Beckwith syndrome: presentation of clinical and cytogenetic data on 22 new cases and review of the literature

The main features of Wiedemann-Beckwith syndrome (WBS) include macroglossia, abdominal wall defects, visceromegaly, gigantism, hypoglycemia, ear creases, nevus flammeus, and mid-face hypoplasia. Twenty-two cases of WBS were examined clinically and cytogenetically, and compared to 226 previously reported cases. Aspects of the clinical evaluations are discussed. All individuals examined were chromosomally normal with no evidence of 11p abnormality as has been reported recently. The relevance of a possible relationship between clinical findings, chromosome abnormalities, and genes present on 11p is discussed. Transmission of this condition is most consistent with autosomal dominant inheritance with incomplete penetrance.