Search

Objective: The aim of this study was to investigate the value of genetic testing using exome sequencing (ES) in oligohydramnios pregnancies with or without other structural abnormalities., Materials and Methods: A total of 110 singleton pregnancies complicated by oligohydramnios were enrolled, including 52 of isolated oligohydramnios and 58 of non-isolated oligohydramnios. All fetal samples were first tested by quantitative fluorescent polymerase chain reaction (QF-PCR) and followed by chromosomal microarray analysis (CMA). Those with normal CMA were informed of the option of trio ES., Results: QF-PCR detected chromosomal abnormality in 4 cases (4/110, 3.6%), including 1 of XXY, 1 of XYY and 2 of triploidy. The remaining 106 cases were tested by CMA, with pathogenic copy number variations (CNVs) detected in 5 cases (5/106, 4.7%), and uniparental disomy (UPD) in 2 cases (2/106, 1.9%). As an option for cases with a normal CMA, ES was accepted by 12 non-isolated cases, and pathogenic or likely pathogenic variants were detected in 5, involving the following genes: PBX1, FREM2, PKHD1 and BBS2, with a 41.7% (5/12) diagnostic rate., Conclusion: We provided further evidence of using advanced genetic approaches for oligohydramnios pregnancy. Non-isolated oligohydramnios increases the risk of having monogenetic conditions., Competing Interests: Declaration of competing interest The author declares that has no conflict of interest regarding the publication of this paper., (Copyright © 2024. Published by Elsevier B.V.)

Introduction: Autosomal recessive renal tubular dysgenesis (ARRTD) is a rare genetic disorder with a very high mortality rate. The typical symptoms of the disease during pregnancy are oligohydramnios, anhydramnios, and nearly all affected fetuses die after birth or have a stillbirth in late gestation, which can adversely increase maternal risks., Methods: Oligohydramnios/anhydramnios can make both amniocentesis for diagnostic testing and morphological evaluation via ultrasound more difficult. In cases of oligohydramnios/anhydramnios suspicious for urinary tract anomalies, amnioinfusion is a meaningful technique that facilitates sampling of amniotic fluid for genetic diagnosis., Results: We report two cases of fetuses with anhydramnios and invisible urinary bladder. Clinical exome sequencing from amniotic fluid revealed a biparentally inherited homozygous pathogenic nonsense ACE variant c.2503G 〉 T [p.Glu853Ter] in proband 1 and a biparentally inherited homozygous pathogenic nonsense ACE variant c.2992C 〉 T [p.Gln998Ter] in proband 2. The prognosis was poor and the patients elected to terminate the pregnancies. Additional post-mortem histopathological examination from the renal tissue of the second fetus showed renal tubular hypoplasia., Conclusion: To our knowledge for the first time, we describe the prenatal diagnosis of ARRTD in Vietnam, and highlight the benefit of detecting ACE variants associated with ARRTD in fetuses with oligohydramnios/anhydramnios through amnioinfusion and amniocentesis, which improves genotype-phenotype correlations and provides valuable information for reproductive counseling., (© 2023 The Authors. Prenatal Diagnosis published by John Wiley & Sons Ltd.)

Objectives: To evaluate the clinical utility of chromosomal microarray analysis (CMA) and whole exome sequencing (WES) in foetuses with oligohydramnios., Methods: In this retrospective study, 126 fetuses with oligohydramnios at our centre from 2018 to 2021 were reviewed. The results of CMA and WES were analysed., Results: One hundred and twenty-four cases underwent CMA and 32 cases underwent WES. The detection rate of pathogenic/likely pathogenic (P/LP) copy number variant (CNV) by CMA was 1.6% (2/124). WES revealed P/LP variants in 21.8% (7/32) of the foetuses. Six (85.7%, 6/7) foetuses showed an autosomal recessive inheritance pattern. Three (42.9%, 3/7) variants were involved in the renin-angiotensin-aldosterone system (RAAS), which are the known genetic causes of autosomal recessive renal tubular dysgenesis (ARRTD)., Conclusion: CMA has low diagnostic utility for oligohydramnios, while WES offers obvious advantages in improving the detection rate. WES should be recommended for fetuses with oligohydramnios.

Objective: To explore the clinical phenotype and genetic variants of a fetus with Glutaracidemia type II C (GA II C)., Methods: Clinical data of a 32-year-old pregnant woman and her fetus with GA II C diagnosed at the Third Affiliated Hospital of Zhengzhou University in December 2021 due to the enlargement and enhanced echo of the kidneys and oligohydramnios fluid at 17 weeks were analyzed retrospectively. Amniotic fluid sample of the fetus and peripheral blood samples of the couple were collected for whole exome sequencing (WES). Candidate variants were verified by Sanger sequencing. Copy number variation (CNV) was detected by using low-coverage whole genome sequencing (CNV-seq)., Results: At 18 weeks' gestation, ultrasound revealed that the fetus had enlargement and enhanced echo of the kidneys along with no echo of renal parenchymal tubular fissure and oligohydramnios. MRI at 22 weeks' gestation confirmed that both kidneys were enlarged with uniformly increased abnormal T2 signal and decreased DWI signal. The volume of both lungs was small, with slightly higher T2 signal. No CNV was detected in the fetus. WES revealed that the fetus has harbored compound heterozygous variants of the ETFDH gene, namely c.1285+1G＞A and c.343_344delTC, which were inherited from its father and mother, respectively. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), both variants were classified as pathogenic (PVS1+PM2_Supporting+PS3_Supporting; PVS1+PM2_Supporting+PM3)., Conclusion: The c.1285+1G＞A and c.343_344delTC compound heterozygous variants of the ETFDH gene probably underlay the disease in this fetus. Type II C glutaric acidemia may manifest as bilateral kidney enlargement with enhanced echo and oligohydramnios. Discovery of the c.343_344delTC has enriched the spectrum of ETFDH gene variants.

We report here a fatal oligohydramnios case, which was suspected due to autosomal recessive polycystic kidney disease at first, but genetic analysis using chorionic tissue and umbilical cord after stillbirth led to the diagnosis of 17q12 deletion syndrome. Subsequent genetic analysis of the parents showed no 17q12 deletion. In this case, if the fetus had autosomal recessive polycystic kidney disease, the recurrence rate in the next pregnancy was suspected to be 25%, but since it was a de novo autosomal dominant disorder, the recurrence rate is extremely low. When a fetal dysmorphic abnormality is detected, a genetic autopsy not only helps to understand the cause but also provides information about the recurrence rate. This information is important for the next pregnancy. A genetic autopsy is useful in cases of fetal deaths or abortions resulting from fetal dysmorphic abnormalities., (© 2023 Japan Society of Obstetrics and Gynecology.)

Introduction: Autosomal recessive renal tubular dysgenesis (ARRTD) is a rare disorder of renal tubular development. ARRTD is a severe condition with high risk of fetal demise and early neonatal death, with only limited case reports of survival over 2 years [Clin Kidney J. 2012 Feb 1;5(1):56-8]. Prenatal diagnosis of ARRTD is challenging, and diagnosis has only previously been confirmed after postnatal or post-mortem investigation., Case: To the best of our knowledge, we describe the first reported case of utilizing targeted genetic testing on the chorionic villous sample (CVS) to identify a homozygous variant in the angiotensinogen (AGT) gene., Discussion: By substantiating the diagnosis of ARRTD prenatally, we allow timely and appropriate counseling during pregnancy., (© 2023 S. Karger AG, Basel.)

Background: Oligohydramnios or polyhydramnios, is associated with chromosomal aberrations, particularly aneuploidy. However, its correlation with copy number variation (CNV) remains unclear., Methods: We retrospectively analyzed 428 cases with an abnormal level of amniotic fluid, comprising of 139 cases of single ultrasound findings (SU group) and 289 cases of multiple ultrasound findings (MU group), by CNV sequencing (CNV-Seq) and followed their pregnancy outcomes., Results: The overall detection rate of clinically significant findings was 8%, with 5% in the SU group and 11% in MU group. Besides, 18 microdeletion/microduplication syndromes were detected, with the highest rate of renal cysts and diabetes syndrome (22%, 4/18). Also, the rate of termination of pregnancy in MU group was much higher than that in the SU group (29% vs. 10%, ***p < 0.001), and in the MU-oligohydramnios subgroup, it was the highest (34%), regardless of cases with chromosomal anomaly and lost to follow-up., Conclusion: Our results showed that the abnormal level of amniotic fluid, especially combined with other ultrasound abnormalities, is closely related to chromosomal abnormalities and genetic CNVs. CNV-Seq may be useful in investigating pregnancies with an abnormal amniotic fluid level., (© 2022 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals LLC.)

Objective: To explore the clinical features and genomic abnorm ality of a fetus enlarged multicystic dysplastic kidneys with oligohydramnios caused by NPHP3 gene mutation., Methods: The fetuse was found to have multicystic dysplastic kidneys with oligohydramnios upon ultrasonography during the second trimester. Following induced abortion, fetal tissue was collected for the extraction of DNA, chromosomal microarray analysis (CMA) and whole exome sequencing (WES). Sanger sequencing was used to verify the suspected variants in the family., Results: Antenatal ultrasound examination at 19 weeks showed "polycystic" kidneys with Oligohydramnios. Delivery was by induced labour because of the critically low amniotic fluid volume. Testing of CMA was normal. WES showed a compound heterozygous mutation of c.1817G>A, p.W606X; c.432dupA, p.E145Rfs*18 mutations are novel mutations in this study., Conclusion: The research may further expand the NPHP3 gene mutation spectrum. Enlarged multicystic dysplastic kidneys with oligohydramnios caused by NPHP3 gene mutation at least include one or two splice site mutation, frameshift mutation or nonsense mutation foetal poor prognosis.

Objective: With this case report, we would like to highlight the importance of a multidisciplinary approach and atypical findings of congenital high airway obstruction sequence (CHAOS), anhydramnios, and renal dysgenesis in the prenatal diagnosis of Fraser syndrome (FS)., Case Report: A 25-year-old primigravida at 19 weeks of routine anomaly scan revealed abnormal sonographic findings such as fetal bilateral dysplastic small kidneys and gross oligohydramnios. The further detailed evaluation revealed that both fetal lungs were hyperechogenic with prominent (dilated) trachea and bronchi suggestive of CHAOS. Based on these findings, a diagnosis of FS was suspected. The couple was counseled and the pregnancy was terminated. The postmortem evaluation and novel homozygous variant in the FRAS1 gene confirmed the diagnosis of FS., Conclusion: The diagnosis and counseling of the patient were supported by a well-coordinated, multidisciplinary approach involving an obstetrician, a fetal medicine specialist, a medical geneticist, and a fetal pathologist., Competing Interests: Declaration of competing interest The authors have no conflicts of interest relevant to this article., (Copyright © 2021. Published by Elsevier B.V.)

Autosomal recessively inherited pathogenic variants in genes associated with the renin-angiotensin-aldosterone system (RAAS) result in early onset oligohydramnios and clinical features of the Potter sequence, typically in association with proximal renal tubules dysgenesis. We describe two siblings and a first cousin who had severe oligohydramnios in the second trimester, and presented at birth with loose skin, wide fontanelles and sutures, and pulmonary insufficiency. Two had refractory hypotension during their brief lives and one received palliative care after birth. All were found to have a homozygous nonsense variant, REN: c.891delG; p.Tyr287*, on exome sequencing. Autopsy limited to the genitourinary system in two of the children revealed normal renal tubular histology in both. Immunoblotting confirmed diminished expression of renin within cultured skin fibroblasts. To our knowledge, this is the first identification of an association between biallelic variants in REN and oligohydramnios in the absence of renal tubular dysgenesis. Due to its role in the RAAS, it has previously been proposed that the decreased expression of REN results in hypotension, ischemia, and decreased urine production. We suggest sequencing of genes in the RAAS, including REN, should be considered in cases of severe early onset oligohydramnios, even when renal morphology and histology are normal., (© 2020 Wiley Periodicals LLC.)

Background: The multiple causes of oligohydramnios make it challenging to study. Long noncoding RNAs (lncRNAs) are sets of RNAs that have been proven to function in multiple biological processes. The purpose of this study is to study expression level and possible role of lncRNAs in oligohydramnios., Methods: In this study, total RNA was isolated from fetal membranes resected from oligohydramnios pregnant women (OP) and normal amount of amniotic fluid pregnant women (Normal). LncRNA microarray was used to analyze the differentially expressed lncRNAs and mRNAs. Kyoto Encyclopedia of Genes and Genomes (KEGG) was used to analyze the main enrichment pathways of differentially expressed mRNAs. Real-time quantitative PCR (qPCR) was used to validate the lncRNA expression level., Results: LncRNA microarray analysis revealed that a total of 801 lncRNAs and 367 mRNAs were differentially expressed in OP; in these results, 638 lncRNAs and 189 mRNAs were upregulated, and 163 lncRNAs and 178 mRNAs were downregulated. Of the lncRNAs, 566 were intergenic lncRNAs, 351 were intronic antisense lncRNAs, and 300 were natural antisense lncRNAs. The differentially expressed lncRNAs were primarily located in chromosomes 2, 1, and 11. KEGG enrichment pathways revealed that the differentially expressed mRNAs were enriched in focal adhesion as well as in the signaling pathways of Ras, tumor necrosis factor (TNF), estrogen, and chemokine. The qPCR results confirmed that LINC00515 and RP11-388P9.2 were upregulated in OP. Furthermore, the constructed lncRNA-miRNA-mRNA regulatory network revealed tenascin R (TNR), cystic fibrosis transmembrane conductance regulator (CFTR), ATP-binding cassette sub-family A member 12 (ABCA12), and collagen 9A2 (COL9A2) as the candidate targets of LINC00515 and RP11-388P9.2., Conclusions: In summary, we revealed the profiles of lncRNA and mRNA in OP. These results might offer potential targets for biological prevention for pregnant women with oligohydramnios detected before delivery and provided a reliable basis for clinical biological treatment in OP.

Objective: We present detection of a familial 1q21.1 microdeletion and concomitant CHD1L mutation in a fetus with oligohydramnios and bilateral renal dysplasia on prenatal ultrasound., Case Report: A 37-year-old, primigravid woman was referred for level II ultrasound examination at 16 weeks of gestation because of oligohydramnios. The parents were phenotypically normal, and there were no congenital malformations in the family. Prenatal ultrasound at 17 weeks of gestation revealed a fetus with fetal growth biometry equivalent to 16 weeks, oligohydramnios with an amniotic fluid index (AFI) of 1.4 cm and bilateral renal dysplasia without sonographic demonstration of bilateral renal arteries. The pregnancy was subsequently terminated, and a 137-g fetus was delivered without characteristic facial dysmorphism. Postnatal cytogenetic analysis of the umbilical cord and parental bloods revealed normal karyotypes. However, array comparative genomic hybridization (aCGH) analysis on the DNA extracted from the umbilical cord revealed a 2.038-Mb microdeletion of 1q21.1-q21.2 encompassing 11 [Online Mendelian Inheritance in Man (OMIM)] genes of PRKAB2, FMO5, CHD1L, BCL9, ACP6, GJA5, GJA8, GPR89B, NBPF14, TRN-GTT2-1 and NBPF20. The mother was found to carry the same microdeletion. A missense mutation of c.2353T > G, p.Ser785Ala in CHD1L was detected in the umbilical cord. The father was found to carry a heterozygous mutation of c.2353T > G, p.Ser785Ala in CHD1L., Conclusion: Fetuses with a 1q21.1 microdeletion and concomitant CHD1L mutation may present oligohydramnios and bilateral renal dysplasia on prenatal ultrasound., (Copyright © 2019. Published by Elsevier B.V.)

Objective: We present prenatal diagnosis of mosaic trisomy 22 at amniocentesis in a pregnancy with facial cleft, oligohydramnios and intrauterine growth restriction (IUGR), and we review the literature., Case Report: A 37-year-old woman underwent amniocentesis at 19 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 47,XX,+22[9]/46,XX[9]. Array comparative genomic hybridization (aCGH) analysis on uncultured amniocytes showed a result of arr(22) × 3 [0.8]. Prenatal ultrasound revealed fetal median facial cleft, oligohydramnios and IUGR. Repeat amniocentesis at 22 weeks of gestation using uncultured amniocytes revealed an aCGH result of arr 22q11.1q13.33 (17,397,498-51,178,264) × 2.8 compatible with 80% mosaicism for trisomy 22, and a fluorescence in situ hybridization (FISH) result of mosaic trisomy 22 with trisomy 22 in 54/100 interphase cells. The cultured amniocytes at repeat amniocentesis had a karyotype of 47,XX,+22[12]/46,XX[8]. The parental karyotypes were normal. Polymorphic DNA marker analysis confirmed a maternal origin of the extra chromosome 22. The pregnancy was terminated, and a 256-g female fetus was delivered with facial dysmorphism and median facial cleft. Cytogenetic analysis of the skin fibroblasts revealed a karyotype of 47,XX,+22[33]/46,XX[7]., Conclusion: Fetuses with high level mosaicism for trisomy 22 at amniocentesis may present IUGR, facial cleft and oligohydramnios on prenatal ultrasound., (Copyright © 2019. Published by Elsevier B.V.)

Objective: We aimed to evaluate fetuses of terminated pregnancies with oligo-or anhydramnios (OAH) to further investigate the association between maternal methylenetetrahydrofolate reductase (MTHFR) polymorphisms and fetal urinary tract malformations., Materials and Methods: This retrospective study included 16 pregnancies with OAH (with normal fetal karyotype) that were intentionally terminated before 22nd gestational week. Fetal autopsy was performed in all cases. We evaluated cases for presence of DNA methylation pathway-related gene polymorphisms., Results: We demonstrated that renal abnormalities and disorders exist in 75% of the cases. Pulmonary system anomalies and single umbilical artery were the most frequently observed associated abnormalities. Polymorphisms with known reduced MTHFR activity were found in 81.8% (9/11) of the cases.Association between urinary system abnormalities and polymorphisms with known reduced MTHFR activity was observed in 88.8% (8/9) of the cases., Conclusion: Physicians should keep in mind that polymorphisms with known reduced MTHFR activity may be associated with urinary tract abnormalities and OAH.

Danshen extract has been used in the treatment of oligohydramnios, however, the mechanism of its action has not been elucidated. Previously, we demonstrated that down-regulation of AQP3 in fetal membranes may contribute to the development of oligohydramnios. In this study, we investigated the effects of Danshen extract on AQP3 expression in human amniotic epithelial cells from term pregnancies with oligohydramnios or those with those with (those with) normovolemic amniotic fluid. Human amniotic epithelial cells from the oligohydramnios group expressed a lower level of AQP3 mRNA and protein than those with normovolemia. Tweleve hour (Twelvehours) of treatment with Danshen extract, in a dose dependent manner, significantly increased the expression of AQP3 in the two groups. However, human amniotic epithelial cells from the oligohydramnios patients showed a greater sensitivity to the treatment of Danshen extract. These data provide a molecular basis for the treatment of patients with oligohydraminos.

Salvia miltiorrhiza is one of the most common Chinese herbal drugs, which is effective to treat oligohydramnios. In this study, the aim was to investigate how Salvia miltiorrhiza regulate aquaporin 3 expression in the human amnion epithelial cells (hAECs) with normal amniotic fluid volume or isolated oligohydramnios, whether via extracellular signal regulated kinase1/2 (ERK1/2) signal transduction pathway or not. Primary hAECs cultures from 120 patients were incubated with Salvia miltiorrhiza or/and ERK1/2 inhibitor-- U0126. Localization of aquaporin 3 was detected by immunohistochemistry and the expression of total ERK1/2, phospho-ERK1/2 (p-ERK1/2) and aquaporin 3 was detected by Western blot. The results were: (1) In hAECs with normal amniotic fluid volume, treatment with 10 µmol/L of U0126 for 6 h resulted in the optimal inhibition of p-ERK1/2 (P<0.05). However, the expression of total ERK1/2 or aquaporin 3 did not significantly change after different concentrations or time of U0126 treatment. Salvia miltiorrhiza significantly up-regulated aquaporin 3 expression, which was not affected by U0126. (2) In hAECs with isolated oligohydramnios, treatment with 5 μmol/L of U0126 for 2 h resulted in the optimal inhibition of p-ERK1/2 and the lowest expression of aquaporin 3 (P<0.05). Moreover, Salvia miltiorrhiza significantly up-regulated aquaporin 3 expression, which was obviously blocked by U0126. These results suggest that Salvia miltiorrhiza may regulate aquaporin 3 expression in hAECs. In addition, in hAECs with isolated oligohydramnios, Salvia miltiorrhiza may regulate the expression of aquaporin 3 via the ERK1/2 signal transduction pathway, which provides a novel thread to the improved treatment for isolated oligohydramnios.

Thirty cases of arthrogryposis associated with longstanding oligohydramnios were identified among 2,500 cases of arthrogryposis (1.2%) and were reviewed for clinical features and natural history. None had renal agenesis or renal disease. Twenty-two had a history of known rupture of membranes. Only 50% had pulmonary hypoplasia at birth and only two died (7%). Sixty percent (18/30) seemed to have their multiple congenital contractures (MCC) primarily on the basis of compression related to the longstanding oligohydramnios and responded well to physical therapy. On average they did not have intrauterine growth restriction. "Potter" facies and remarkable skin changes were present in all. An excess of males was observed in spite of the lack of genitourinary anomalies., (© 2014 Wiley Periodicals, Inc.)

Objective: The aim of this study was to document the association between pancreatic agenesis or hypoplasia and multicystic renal dysplasia related to transcription factor 2 (TCF2) or hepatocyte nuclear factor 1 beta mutations., Methodology: We describe the phenotype of the pancreas and the kidneys from three fetuses heterozygous for a mutation of TCF2., Cases: Case 1 had bilateral hyperechogenic, multicystic kidneys, bilateral clubfoot and pancreatic agenesis. Case 2 had two enlarged polycystic kidneys, anamnios and pancreatic agenesis. Case 3 had multicystic renal dysplasia, oligohydramnios and hypoplasia of the tail of the pancreas., Conclusion: TCF2 mutations are frequently discovered in fetuses presenting with bilateral hyperechogenic kidneys. The association between pancreatic agenesis and a TCF2 mutation has not previously been reported. TCF2 deficiency in mice leads to pancreatic agenesis, suggesting that the gene is essential for pancreatic development. Our observations indicate the importance of visualizing the pancreas during ultrasound examinations if renal malformations are discovered., (© 2013 John Wiley & Sons, Ltd.)

Objective: The epsilon gamma delta beta (εγδβ)-thalassemias are rare sporadic disorders caused by deletion of the β-globin gene cluster. The main clinical feature is marked prenatal and neonatal anemia that resolves spontaneously within a few months. Reports originating mainly from Europe have so far identified 30 such deletions The aim of the present work was to describe a novel 1.78-Mb deletion, the longest ever reported, and to detail the clinical features in 12 members of an extended Bedouin family., Methods: The deletion was identified by globin gene multiplex ligation-dependent probe amplification (MLPA) of the β-globin cluster and further characterized by comparative genomic hybridization. Past and present clinical and laboratory data of ten symptomatic and two asymptomatic patients were collected., Results: A 1.78-Mb εγδβ-deletion, the largest ever described, was identified in all patients. Although other genes were included in the deletion, no other symptoms were observed. Of the ten symptomatic fetuses and neonates, three died of the disease. The remainder required packed cell transfusions during the first months of life. Pregnancy complications included intrauterine growth restriction and oligohydramnios, as well as additional neonatal complications including prematurity and persistent pulmonary hypertension of the neonate., Conclusions: We suggest that εγδβ-thalassemia be added to the list of hemoglobinopathies that can cause neonatal anemia and that MLPA of the β-globin cluster be used to confirm its diagnosis. Careful surveillance during pregnancy is important to reduce neonatal mortality and morbidity, especially given the dramatic improvement that occurs later., (© 2012 John Wiley & Sons A/S.)

Background: Pulmonary hypoplasia resulting from oligohydramnios or anhydramnios can cause severe respiratory compromise in newborn patients. We report a case of recurrent oligohydramnios in a mother with an ErbB4 mutation and speculate that the effects on the placenta through decreased vascularization contributed to oligohdyramnios and subsequent pulmonary hypoplasia in the newborn., Case: The pregnant mother in this case had two subsequent term pregnancies complicated by severe oligohydramnios. Both pregnancies resulted in live born female neonates with pulmonary hypoplasia, pneumothoraces, and pulmonary hypertension. The mother and second newborn, who died, were found to have the ErbB4 mutation. Examination of the placenta with that pregnancy showed decreased vascularity., Conclusion: ErbB4 may have important effects on placental development and hydramnios that also may affect neonatal pulmonary hypoplasia.

Previous studies by our group as well as other researchers have found expression of Aquaporins (AQPs) 1, 3, 8, and 9 in human chorioamniotic membranes and placenta. Our previous study found that the alteration of the expression of AQPs 1, 3, 8, and 9 in placenta and fetal membranes was an adaptive response to maintain amniotic fluid homeostasis in case of abnormal amniotic fluid volume, which is likely to affect the intramembranous absorption and transport of water and solute from mother to fetus. However, the actual regulation mechanisms of intramembranous absorption and placental water flow are not yet clear, making it difficult to treat abnormal amniotic fluid volume effectively. Several studies found that many factors, including hormone levels, osmotic pressure, temperature, and oxygen concentration, regulate expression of AQPs in placenta, fetal membranes, and other mammalian organs through several signal transduction pathways, such as the cAMP, the MAPK, the PI3K/AKT, and the PKC pathways. These factors could provide potential therapeutic targets for the treatment of abnormal amniotic fluid volume.

We report on a triplet pregnancy of consanguineous parents with one fetus being affected by recurrent Johanson-Blizzard syndrome (JBS). At autopsy in the 35th gestational week, the affected triplet presented with an especially severe and lethal manifestation of the disorder as compared to his elder affected brother and to cases in the literature, thus exemplifying great interfamilial and intrafamilial phenotypic variability. Arhinencephaly and cystic renal dysplasia associated with urethral obstruction sequence were features not described previously in the literature. In addition to the lack of exocrine acini as the characteristic feature of JBS, the pancreas revealed a resorptive inflammatory reaction with infiltration by eosinophilic granulocytes that focally dispersed onto islets of Langerhans, thus favoring a progressive destructive rather than primary dysplastic process and possibly explaining the occurrence of diabetes mellitus in later life. JBS maps to chromosome 15q15-q21.1 and is associated with mutations in the UBR1 gene. Testing the fetus and the affected sibling revealed a homozygous truncating mutation in UBR1. The resulting absence of the UBR1 protein was confirmed by Western blot. Immunohistochemical staining using a commercial anti-UBR1 antibody demonstrated staining, presumably artifactual. This finding suggests that, until an appropriately validated antibody has been identified, this modality should not be utilized for diagnosis or confirmation of this disorder.

Retinoids (active derivatives of vitamin A) were already demonstrated to be important morphogenes and their implication at the placental and fetal level was already established. A new field of research is now developed in order to show their role on fetal membranes constituted by amnion and chorion. To describe the role of retinoids on these membranes, our studies were focused on target gene research. Firstly, all metabolism enzymes needed to vitamin A pathways were demonstrated to be present and active in signal transduction. Secondly, a bioinformatic analysis was performed to assess a list of potential target genes that could be classified in different biological pathways (inflammation, retinoids, hormones, vascularization, extracellular matrix and water homeostasis). Then, it was demonstrated that the gene coding for PLAT, implied in the degradation of extracellular matrix during programmed or premature rupture of membranes, is regulated by retinoids in a two steps mechanism. Finally, preliminary data showed that some aquaporins, which control water transport across membranes, are expressed and regulated by retinoids in the fetal membranes. A disregulation in pathologies like oligo or poly-hydramnios can be anticipated. Improvement of our knowledge about the retinoid implications is a key point in order to obtain a precise and complete documented cartography of the vitamin A (regulating) in amniotic membranes (regulated) that will permit the development of new diagnostic and therapeutic strategies., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Inherited renal tubular dysgenesis (RTD) is caused by mutations in the genes encoding components of the renin-angiotensin cascade: angiotensinogen, renin, angiotensin-converting enzyme (ACE), and angiotensin ΙΙ receptor type 1. It is characterized by oligohydramnios, prematurity, hypotension, hypocalvaria, and neonatal renal failure. The histological hallmark is the absence or poor development of renal proximal tubules. Except for a few cases, the prognosis has been thought to be universally poor, with patients dying either in utero or shortly after birth. We report a 3-year-old infant diagnosed clinically with RTD. The infant survived the neonatal period after 2 weeks of anuria subsequently subsiding. Hypotension and hyperkalemia normalized eventually with administration of fludrocortisone. A revision of renal tissue obtained from a sibling that died shortly after birth revealed normal glomeruli and distal tubules but no identifiable proximal tubules. A novel mutation in the ACE gene was found in the surviving child, who remains with stage 4 chronic kidney disease and normal neurodevelopment. As the number of surviving cases of RTD increases, it should be emphasized to the parents and the neonatal care team that it may not be universally fatal as previously reported. A trial of fludrocortisone may correct hyperkalemia and hypotension.

Prune belly syndrome is a rare congenital disorder characterized by deficiency of abdominal wall muscles, cryptorchidism, and urinary tract anomalies. We have had the opportunity to study a baby with prune belly syndrome associated with an apparently de novo 1.3-megabase interstitial 17q12 microdeletion that includes the hepatocyte nuclear factor-1-beta gene at 17q12. One previous patient, an adult, has been reported with prune belly syndrome and a hepatocyte nuclear factor-1-beta microdeletion. Hepatocyte nuclear factor-1-beta is a widely expressed transcription factor that regulates tissue-specific gene expression and is expressed in numerous tissues including mesonephric duct derivatives, the renal tubule of the metanephros, and the developing prostate of the mouse. Mutations in hepatocyte nuclear factor-1-beta cause the "renal cysts and diabetes syndrome," isolated renal cystic dysplasia, and a variety of other malformations. Based on its expression pattern and the observation of two affected cases, we propose that haploinsufficiency of hepatocyte nuclear factor-1-beta may be causally related to the production of the prune belly syndrome phenotype through a mechanism of prostatic and ureteral hypoplasia that results in severe obstructive uropathy with urinary tract and abdominal distension., (Copyright Thieme Medical Publishers.)

Background: We report the familial recurrence of urethral stenosis/atresia in two sibling fetuses with bladder outlet obstruction, severe oligohydramnios, and pulmonary hypoplasia. Urethral obstruction in the fetus, when severe, results in a dilated urinary bladder (megacystis) and associated urinary anomalies (hydroureter, hydronephrosis, renal dysplasia). Distention of the fetal abdomen, the result of megacystis or urinary ascites, leads to stretching and eventually hypoplasia or even absence of abdominal muscles., Cases: This constellation of findings, known by a variety of terms including "prune belly" syndrome, is associated with a variety of urethral changes, including posterior urethral valves and urethral stenosis/atresia. One fetus manifested unilateral postaxial polydactyly of the left hand., Conclusions: A microdeletion of 6p25.3, identified in mother and one fetus, is not associated with a gene known to be involved in urethral development and therefore of unknown significance., ((c) 2009 Wiley-Liss, Inc.)

Objective: To explore the pathophysiology of oligohydramnios, the association between the expression of aquaporin 1 and aquaporin 3 in fetal membranes and placenta and oligohydramnios was investigated., Methods: Sixty patients underwent elective cesarean sections at term were studied, 30 patients with isolated oligohydramnios and the other 30 with normal amniotic fluid volume (AFV). Real-time polymerase chain reaction and immunohistochemistry were employed to determine expression and localization of aquaporin 1 and aquaporin 3 in amnion, chorion and placenta, respectively., Results: The expression of aquaporin 1 and aquaporin 3 was detected in amnion, chorion and placenta using real-time RT-PCR. By immunohistochemistry, aquaporin 1 and aquaporin 3 protein expressions in amnion epithelia and chorion cytotrophoblasts were identified. In placenta, aquaporin 1 was detected in placental vessels, while aquaporin 3 was found in trophoblast cells. In comparison to normal AFV group, there was a significant decrease of aquaporin 1 expression in amnion in oligohydramnios group, but no significant difference in chorion and placenta between the two groups. The expression of the aquaporin 3 in amnion and chorion in oligohydramnios group was significantly decreased, while expression in placenta was significantly increased compared with that in normal AFV group., Conclusions: Alteration of aquaporin 1 and aquaporin 3 expression in fetal membranes and placenta may be important in the pathophysiology of isolated oligohydramnios.

Renal tubular dysgenesis (RTD) is a clinical disorder either acquired during fetal development or inherited as an autosomal recessive condition. Inherited RTD is caused by mutations in the genes encoding the components of the renin-angiotensin system angiotensinogen, renin, angiotensin-converting enzyme and angiotensin II receptor type 1. Inherited RTD is characterized by early onset oligohydramnios, skull ossification defects, preterm birth and neonatal pulmonary and renal failure. The histological hallmark is the absence or poor development of proximal tubules. So far, all patients died either in utero or shortly after birth. We report the first patients with inherited RTD surviving the neonatal period and still being alive. Genetic and functional analysis of the renin-angiotensin system contributes to the diagnosis of RTD. In conclusion, the clinical diagnosis of inherited RTD is easily missed after birth without renal biopsy or information on affected family members. Genetic and functional analysis of the renin-angiotensin system contributes to correct diagnosis.