Prenatal diagnosis of pyloric atresia-junctional epidermolysis bullosa syndrome in a fetus not known to be at risk

Junctional epidermolysis bullosa with pyloric atresia (PA-JEB) is a highly lethal, inherited, autosomal recessive disease. Thus far, prenatal diagnosis of this syndrome was only realized on pregnancies at risk for recurrence. We report the case of a 26-year-old woman, first cousin to her husband, who had undergone amniocentesis for polyhydramnios. The karyotype was normal but the amniotic fluid contained acetylcholinesterase. A targeted scan at 25 weeks' gestation did not find spina bifida, but polyhydramnios with a dilated stomach, and several other anomalies: echogenic particles in the amniotic fluid, a thin skin which closely adhered to the nasal bones, narrow nostrils, abnormal ears, fisted hands, malposition of both first toes, and kidney malformation. Despite no previous case in the family, it was thought that sonographic findings were suggestive of the PA-JEB syndrome. A fetal skin biopsy was carried out at 28 weeks' gestation. The ultrastructural examination of fetal skin displayed JEB. Genetic analysis detected a homozygous mutation in the gene encoding integrin alpha 6. Termination of pregnancy was carried out at 29 weeks' gestation. These results illustrate that in the case of a fetus not known to be at risk, diagnosis of PA-JEB can be achieved by ultrasound findings leading to fetal skin biopsy and ultrastructural examination of blistered epidermis. Some new sonographic signs should raise the possibility of significant cutaneous desquamation and blister formation in a fetus, especially when there is positive amniotic acetylcholinesterase coupled with elevated alpha-fetoprotein or suspected pyloric atresia.

First prenatal diagnosis of defects in the HsPDX1 gene encoding protein X, an additional lipoyl-containing subunit of the human pyruvate dehydrogenase complex

We have previously reported a genetic study of a neonatal lactic acidosis linked to a pyruvate dehydrogenase complex deficiency due to the absence of the protein X subunit. This rare autosomal recessive disorder is associated with specific deletions in this polypeptide which is encoded by the HsPDX1 gene, located on chromosome 11p1.3. The pathology of the patient was considered to arise from a large homozygous deletion (78del85) found at the 5' end of the HsPDX1 coding sequence. Her heterozygous mother underwent prenatal diagnosis during a subsequent pregnancy. Chorionic villus samples were used for three independent studies: (1) normal levels of the protein X component of the PDH complex were detected by immunoblotting; (2) RT-PCR analysis showed no deletion at the 5' end of the cDNA but the presence of a distinct heterozygous deletion (965del59) at its 3' end inherited from the father; (3) haplotype analysis revealed the presence of the father's mutated allele and the mother's normal allele. It was concluded that the fetus was heterozygous for this separate 3' deletion, so, it was likely to be not affected. This study permitted us to characterize more precisely the genetic abnormalities of the HsPDX1 cDNA occurring in each family's member.

The reasons for termination of pregnancy in the third trimester

OBJECTIVE

To analyse the process in making decisions leading to termination of pregnancy in the third trimester and to evaluate the maternal morbidity associated with this procedure.

DESIGN

Retrospective study.

SETTING

The Maternité Port Royal University Hospital, Paris, France.

POPULATION

A consecutive series of 956 terminations of pregnancy performed for fetal anomalies in singleton pregnancies, 305 of which were in the third trimester and 651 in the second.

MAIN OUTCOME MEASURES

Indications for termination of pregnancy; process leading to late termination of pregnancy; maternal morbidity.

RESULTS

One hundred and thirteen (37%) third trimester terminations of pregnancy were associated with false negative resulted from the results of earlier screening tests. In 15 terminations (5%), the decision was postponed, although the poor fetal prognosis was established earlier. In 55 (18%) the diagnosis was not possible earlier than the third trimester, and in 122 (40%) the diagnosis was possible earlier but the poor prognosis for the fetus was not established until the third trimester. Maternal morbidity due to termination of pregnancy was similar in the second and third trimester.

CONCLUSION

One-third of late terminations of pregnancy could have been avoided by more efficient screening in the second trimester. However, because fetal prognosis is not always clear when a malformation is diagnosed, postponing the decision until fetal development allows more thorough evaluation and may avoid unnecessary termination of pregnancy in the second trimester. This could be the main beneficial aspect of not setting a limit to the gestational age for performing termination of pregnancy.

Prenatal diagnosis of a satellited non-acrocentric chromosome derived from a maternal translocation (10;13)(p13;p12) and review of literature

We identified a familial balanced translocation involving chromosomes 10 and 13 through the finding of a satellited 10p chromosome in a fetus. The phenotype of two unbalanced products of the translocation resulting in pure monosomy 10p13 and trisomy 10p13 is described. This familial case and two of our unreported cases are discussed in the light of other prenatal observations with satellited non-acrocentric chromosomes reported in the literature.

Prenatal detection of a 1p36 deletion in a fetus with multiple malformations and a review of the literature

The prenatal diagnosis of a 1p36 deletion is reported. The pregnancy was ascertained at 24 weeks of gestation because of the discovery of multiple malformations at ultrasound including hypotelorism, moderate cerebral ventricular dilatation and Ebstein anomaly with secondary cardiac failure. Following cytogenetic studies and counselling, the pregnancy was terminated and a fetal autopsy performed. The phenotype of this antenatally-diagnosed case is compared with the clinical features of 44 previously reported cases with an identical deletion of the short arm of chromosome 1p36.

Lung growth and maturation after tracheal occlusion in diaphragmatic hernia

Tracheal occlusion (TO) was performed at 120 d of gestation by noninvasive endoscopic technique using a releasable latex balloon, in fetal lambs with diaphragmatic hernia (DH) established at 85 d. The lungs were studied at 139 d in five fetuses with DH + TO, five fetuses with DH only, and six control fetuses. Fluid retention consecutive to TO allowed fetal lungs to grow. Histological pulmonary structure was more mature in DH + TO than in DH alone. The growth-inducing effect of TO was however incomplete, with an increased protein/DNA ratio. Tissue phospholipids were increased, but this was not reflected in the surfactant compartment. The major surfactant component, disaturated phosphatidylcholine, was reduced to 58% of its control value in DH, and further reduced to 17.5% of its control value in DH + TO. The proportion of surfactant protein B immunoreactive cells, assumed to represent the proportion of type II cells, was increased in DH (27% of all parenchymal cells), and reduced in DH + TO (7.8%) as compared with control fetuses (15%). In conclusion, although noninvasive tracheal occlusion in utero is feasible and may partly compensate the adverse effects of DH on lung organogenesis, it reduces the number of type II cells and induces a dramatic surfactant deficit. Using this technique in human fetuses requires careful consideration until further evaluation of lung functional characteristics has been achieved in this experimental model.

Congenital adenomatoid malformation of the lung: when is active fetal therapy indicated?

OBJECTIVE

Although aggressive fetal therapies such as thoracoamniotic shunting can be applied to cystic adenomatoid malformations of the lung diagnosed in utero, there is no clear consensus regarding their indications. Our purpose was to evaluate a management policy in which aggressive fetal therapy was restricted to those cases complicated by major polyhydramnios or hydrops; all other cases were managed conservatively.

STUDY DESIGN

A prospective cohort study of 33 cases with a prenatal diagnosis of cystic adenomatoid malformations of the lung was performed. Thoracoamniotic shunting was offered only in nine macrocystic cases with acute polyhydramnios or hydrops.

RESULTS

Four cases were diagnosed postnatally as sequestrations. Of 12 cases complicated by acute polyhydramnios or hydrops, 5 survived (1 type III with spontaneous incomplete resolution in utero, 4 type I with substantial volume reduction after shunting). The 17 cases without acute polyhydramnios or hydrops were managed conservatively and survived.

CONCLUSION

Conservative management is indicated in cases of cystic adenomatoid malformations of the lung without acute polyhydramnios or hydrops.

Detection of maternal cells in human fetal blood during the third trimester of pregnancy using allele-specific PCR amplification

Using a highly sensitive allele-specific PCR amplification method, we have previously shown that maternal cells could be detected in all 10 cord bloods tested. This raised the question of whether maternal cells are released into cord blood during the process of delivery or whether they are already present during pregnancy. We have now used the same PCR method to detect the presence of maternal cells in nine fetal blood samples collected at different gestational ages. Maternal cells were detected in eight samples obtained between 24 and 35 weeks of gestation. They were estimated to amount between 10(-4) and 10(-5) of nucleated fetal blood cells. In two cases mononuclear and polymorphonuclear cell fractions were separated by Ficoll gradient centrifugation and maternal cells were detected as comparable levels in both fractions. Maternal cells could not be detected in the one fetal blood sample obtained at 20 weeks of gestation, suggesting that maternal cells could appear at detectable levels in fetal blood during the third trimester of pregnancy. These results are discussed in terms of materno-fetal immune tolerance and of transmission of viruses (and more specifically of the human immunodeficiency virus) from mother to child.

Tracheal obstruction in experimental diaphragmatic hernia: an endoscopic approach in the fetal lamb

Congenital diaphragmatic hernia (CDH) is associated with a neonatal mortality of up to 50 per cent resulting from pulmonary hypoplasia. Experimental ligation of the trachea increases pulmonary growth in fetuses with experimental diaphragmatic hernia (EDH). To provide a potentially reversible tracheal occlusion (TO) using a minimally invasive procedure, we designed the endoscopic placement of a latex tracheal balloon in fetal lambs with EDH. Following surgical creation of a left EDH at 85 days' gestation, endoscopic occlusion of the fetal trachea was performed at 120 days. The fetuses were retrieved at 139 days. The procedure was successful in 5/11 attempts, resulting in liveborns in which the balloon occluded the trachea completely with expanded lungs and reduction of the herniated viscera into the abdomen. These cases were compared with five cases of EDH without TO and six controls. In the TO group, the lung weight was significantly greater but the radial alveolar count, DNA content, and protein content were similar to normal controls. All lung growth parameters were greater in the TO than in the EDH group. Occlusion of the trachea using an endoscopic technique could provide a useful alternative to open fetal surgery in fetuses with CDH.

Development of human fetal kidney in obstructive uropathy: correlations with ultrasonography and urine biochemistry

In utero urethral obstruction results in bilateral hydronephrosis and severe fetal and post-natal morbidity and mortality. Obstetrical management depends on the indirect evaluation of fetal renal function by ultrasonography and biochemical analysis. No direct evaluation of the severity and possible reversibility of renal lesions is available. In this paper we analyzed kidneys from 34 fetuses (14 to 37 gestational weeks) in which (1) isolated bilateral urinary tract obstruction had been detected in utero by sonography, and (2) the severity of sonographic and biochemical prognostic indicators led to the indication of termination of pregnancy or to perinatal death. Pure hydronephrosis was observed in two young fetuses [14 and 20 gestational weeks (GW)] and was associated with regressive changes in two others. In contrast, a wide spectrum of dysplastic renal lesions was present in 30 fetuses and was classified into four subgroups according to the association of dysplasia, hypoplasia and cysts. They had the following characteristics in common: (1) premature cessation of nephrogenesis assessed by the medullary ray counting method; (2) early disappearance or myofibroblastic differentiation of metanephric blastema; (3) early increase in interstitial mesenchyme with widespread expression of alpha-smooth muscle actin by mesenchymal cells; (4) frequent absence of classical criteria of dysplasia (nests of cartilage were observed in only 5 fetuses); (5) an identification, based upon the detection of alpha-smooth muscle actin expression, of the muscular phenotype of mesenchymal cells encircling primitive ducts. In conclusion, (1) the value of prognostic markers in fetuses less than 20 GW should be reconsidered; (2) after 20 GW there is a good correlation between markers predicting poor prognosis and the severity of renal lesions; (3) hypoplasia with disappearance of blastema cells, dysplasia and early interstitial fibrosis are evidence of the irreversibility of renal lesions and preclude any possibility of new nephron formation; (4) these findings suggest that most surgical in utero procedures are performed when irreversible renal lesions have developed.

Development of human renal function: reference intervals for 10 biochemical markers in fetal urine

Evaluation of fetal renal function by analysis of fetal urine sampled in utero may improve perinatal care after a prenatal diagnosis of bilateral obstructive uropathy. We provide reference intervals for 10 fetal urinary compounds and examine their variation with gestational age. Forty-one fetuses with bilateral obstructive uropathy (urine sampled between 20 and 38 weeks of gestational age) had normal, healthy values for serum creatinine (< or = 50 mumol/L) at ages 1-2 years. These cases were thus assumed to represent a reasonable approximation to healthy values. Sodium and beta 2-microglobulin concentrations significantly decreased with gestational age; calcium, ammonia, and creatinine significantly increased; glucose, phosphorus, chloride, urea, and total protein concentrations did not vary. Our results provide reference values for prenatal evaluation of fetal renal function and suggest that glomerular filtration of macromolecules and tubular reabsorption of glucose and phosphorus are mature by 20 weeks of gestation, whereas tubular reabsorption of sodium and beta 2-microglobulin increases progressively during the second half of gestation.

Development of human renal function: reference intervals for 10 biochemical markers in fetal urine

Evaluation of fetal renal function by analysis of fetal urine sampled in utero may improve perinatal care after a prenatal diagnosis of bilateral obstructive uropathy. We provide reference intervals for 10 fetal urinary compounds and examine their variation with gestational age. Forty-one fetuses with bilateral obstructive uropathy (urine sampled between 20 and 38 weeks of gestational age) had normal, healthy values for serum creatinine (&lt; or = 50 mumol/L) at ages 1-2 years. These cases were thus assumed to represent a reasonable approximation to healthy values. Sodium and beta 2-microglobulin concentrations significantly decreased with gestational age; calcium, ammonia, and creatinine significantly increased; glucose, phosphorus, chloride, urea, and total protein concentrations did not vary. Our results provide reference values for prenatal evaluation of fetal renal function and suggest that glomerular filtration of macromolecules and tubular reabsorption of glucose and phosphorus are mature by 20 weeks of gestation, whereas tubular reabsorption of sodium and beta 2-microglobulin increases progressively during the second half of gestation.

Fetal serum interferon-alpha suggests viral infection as the aetiology of unexplained lateral cerebral ventriculomegaly

We assayed fetal serum interferon-alpha (IFNA), a cytokine produced by leukocytes as a response to viral infection, in a series of 59 consecutive cases of ventriculomegaly diagnosed in utero and in 89 controls. Results were correlated with other findings including karyotype, maternal-fetal screening for serum antibodies to specific infectious pathogens, viral cultures of amniotic fluid, and neuropathological examination or postnatal follow-up. Fetal serum IFNA assay was negative in the five ventriculomegalies associated with a genetic anomaly and positive in the three cases with documented cytomegalovirus infections. In addition, fetal serum IFNA was detected significantly more often in the cases of ventriculomegaly with unexplained pathogenesis (15/51, 29.4 per cent) than in controls (1/89, 1.1 per cent). Detection of IFNA suggestive of viral infection in fetuses with otherwise unexplained ventriculomegaly underscores the need for more extensive viral screening in such cases.

Serial transabdominal amnioinfusion in the management of gastroschisis with severe oligohydramnios

Two fetuses with gastroschisis diagnosed in utero (at 19 weeks' gestation) had severe oligohydramnios at 30 to 31 weeks. Serial transabdominal amnioinfusions were performed to fill the amniotic cavity with saline, thereby avoiding the potential consequences of fetal exposure to severe oligohydramnios. In both cases, premature rupture of membranes occurred at 36 weeks, and the fetuses were delivered by cesarean section. There were minimal lesions of the extraabdominal bowel. After primary closure of the abdomen, the postoperative course was uneventful. These observations show that serial amnioinfusion is a feasible therapeutic approach for severe third-trimester oligohydramnios associated with gastroschisis.

First-trimester translucency: aneuploidy, sonographic findings, and maternal age

The positive predictive value of 1st-trimester nuchal translucency for the diagnosis of fetal aneuploidy is reported to range from 19 to 72% in retrospective series and from 2.8 to 4.8% in prospective studies. In order to analyze the biases accounting for such discrepancies, we retrospectively analyzed a consecutive series of 66 cases of translucency and studied the rate of aneuploidy as a function of sonographic findings and maternal age. The aneuploidy rate was significantly higher in the 23 cases in whom translucency involved the fetal trunk (65%) than in the 43 cases in whom translucency was confined to the nuchal area (16%). This rate was not significantly higher in septated translucencies. These trends persisted after adjustment for maternal age, but the rate of chromosomal anomalies was twice lower in younger mothers. Among the 46 cases in whom the maternal age was < 35 years, 10% of the 30 fetuses with localized nuchal translucency had an abnormal karyotype. In contrast, the rate of aneuploidy was 85% among the 7 cases with diffuse translucency for whom the maternal age was 35 years or above. These findings confirm that both maternal age and size of the translucency should be taken into account to evaluate the risks of aneuploidy.

Congenital diaphragmatic hernia: can prenatal ultrasonography predict outcome?

OBJECTIVE

We wanted to establish whether prenatal ultrasonography predicts postnatal outcome in congenital diaphragmatic hernia.

STUDY DESIGN

We designed a retrospective multicenter cohort study of 135 patients with congenital diaphragmatic hernia (122 left, 10 right, 2 bilateral, 1 anterior). In isolated left congenital diaphragmatic hernia five potential prenatal prognostic factors were studied: diagnosis at < or = 25 weeks' gestation, polyhydramnios, intrathoracic stomach, small abdomen, and major mediastinal shift.

RESULTS

None of the 44 fetuses or infants who had multiple malformations survived. Of the 91 cases of isolated congenital diaphragmatic hernia, there were 82 live births; 76 of these infants had a left congenital diaphragmatic hernia. Of these, 51 (67%) died postnatally. A statistically significant relation was found between mortality and polyhydramnios, intrathoracic stomach, and major mediastinal shift. Mortality increased as a function of the number of these prognostic factors from 20% when none was present to 94% when all three were present.

CONCLUSION

In the majority of cases of isolated left congenital diaphragmatic hernia the prognostic value of fetal ultrasonography is too low to alter perinatal management.

International, collaborative experience of 1789 patients having multifetal pregnancy reduction: a plateauing of risks and outcomes

OBJECTIVE

To develop the most up-to-date, complete data base of multifetal pregnancy reduction (MFPR) from cases, and to provide the best counseling for couples with multifetal pregnancies.

METHODS

From nine centers in five countries, 1789 completed MFPR cases were collected and outcomes evaluated. Pregnancy losses were defined as through 24 weeks and deliveries categorized in groups of 25-28, 29-32, 33-36, and 37 or more weeks.

RESULTS

Overall, the pregnancy loss rate was 11.7% but varied from a low of 7.6% for triplets to twins and increased with each additional starting number to 22.9% for sextuplets or higher. Early premature deliveries (25-28 weeks) were 4.5% and varied with starting number. Loss rates by finishing number were highest for triplets and lowest for twins, but gestational age at delivery was highest for singletons.

CONCLUSIONS

Multifetal pregnancy reduction has been shown to be a safe and effective method to improve outcome in multifetal pregnancies. Outcomes are worse with higher-order gestations and support the need for continued vigilance of fertility therapy.