Prenatal Diagnosis of Oral Teratoma by Ultrasound.

A pregnant woman had a normal second-trimester anatomic survey at 22 weeks gestation. She was revealed to have a fetal oral mass with polyhydramnios and invisible stomach bubble by ultrasound at 28 weeks. A 50 mm × 36 mm × 42 mm, solid mass was found in the fetal mouth, filling the entire oral cavity. Fetal magnetic resonance imaging showed a homogeneous solid mass in the oral cavity compressing the hypopharynx. At 33 weeks, preterm labor occurred because of the continuation of increased amniotic fluid volume, and a female infant was vaginally delivered. The infant died shortly after tracheal intubation attempt failed. Autopsy confirmed the prenatal sonographic finding. The final pathologic diagnosis was oral immature teratoma. Our study indicates that although oral teratomas are rare, they are readily apparent at prenatal sonographic examinations. Respiratory compromise is the frequent complication of oral teratomas, which is associated with high perinatal mortality.

Fetal phenotype of CHARGE syndrome with a molecular confirmation: a series of 13 cases.

Introduction CHARGE syndrome is an autosomal dominant genetic disorder with known pattern of features. The aim of the study was to present the fetal features of CHARGE syndrome to gain awareness that the antenatal characteristics can be very nonspecific. Case Presentation This was a retrospective study of 13 cases with CHARGE syndrome diagnosed by prenatal or postnatal genetic testing and physical examination. Two (15.4%; 2/13) had normal ultrasound scans during pregnancy. One (7.7%; 1/13) with first-trimester cystic hygroma presented intrauterine fetal demise (IUFD) at 16 weeks gestation. The remaining 10 (76.9%; 10/13) cases had abnormal ultrasound features in utero; among these, 1 had an increased nuchal translucency in the first trimester, 5 had second-trimester abnormal ultrasounds including micrognathia, cardiac defects and facial defects, and 4 third-trimester abnormal ultrasounds including micrognathia, isolated fetal growth restriction and polyhydramnios. Among the 11 cases with abnormal prenatal ultrasound scans, no fetus could reach the diagnostic criteria of CHARGE syndrome if only based on the results of ultrasound. However, the diagnosis was made in all cases when CHD7 defects were detected. Discussion/Conclusion The CHARGE syndrome presents non-specific abnormal ultrasound markers in utero. Exome sequencing in the genetic work up will aid in prenatal diagnosis of this syndrome.

Early Onset of Severe Anemia Caused by Hb Calgary (HBB: C.194G > T): Another Case Report.

Unstable hemoglobin (Hb) variants are a rare cause of congenital hemolytic anemia. We describe a Chinese girl who presented with transfusion-dependent anemia in early infancy. Her diagnosis of Hb Calgary [ß64(E8)Gly > Val; HBB:c.194G > T] was not made until molecular testing was performed at the age of 5 years. Our case highlights the importance of early genetic testing in order to make the diagnosis, which may not only be useful for patient management and family counseling, but also for avoiding further unnecessary investigative attempts.

A 6-Year Follow-up of a Chinese Child with Homozygous ß0-Thalaasemia and a Heterozygous KLF1 Mutation.

Patients with the genotype of ß0/ß0 for ß-thalassemia (ß-thal) usually behave as ß-thal major (ß-TM) phenotype which is transfusion-dependent. The pathophysiology of ß-thal is the imbalance between α/ß-globin chains. The degree of α/ß-globin imbalance can be reduced by the more effective synthesis of γ-globin chains, and increased Hb F levels, modifying clinical severity of ß-TM. We report a Chinese child who had homozygous ß0-thal and a heterozygous KLF1 mutation. The patient had a moderate anemia since 6 months old, keeping a baseline Hb value of 8.0-9.0 g/dL. She had normal development except for a short stature (3rd percentile) until 6 years old, when splenomegaly and facial bone deformities occurred. Although genetic alteration of KLF1 expression in ß0/ß0 patients can result in some degree of disease alleviation, our case shows that it is insufficient to ameliorate satisfactorily the presentation. This point should be borne in mind for physicians who provide the genetic counseling and prenatal diagnosis to at-risk families.

Clinical and molecular analysis of nine fetal cases with clinically significant variants causing nemaline myopathy.

OBJECTIVE: To present the prenatal features and postnatal outcomes of pregnancies with fetal nemaline myopathy (NM). STUDY DESIGN: This was a retrospective study of nine cases with NM diagnosed by prenatal or postnatal clinical features and confirmed by genetic testing. Clinical and laboratory data were collected and reviewed for these cases, including maternal demographics, prenatal sonographic findings, exome sequencing (ES) results, and pregnancy outcomes. RESULTS: All of the nine cases were detected to have NM-causing variants, involving NEB gene in 2 cases, ACTA1 in 3 cases, KLHL40 in 3 cases, and TPM2 in 1 case. Almost all (8/9) had normal first-trimester ultrasound scans except one who had an increased nuchal translucency. Seven (7/9) cases had second-trimester abnormal ultrasounds with fetal akinesia and/or extremity anomalies. Two (2/9) had only third-trimester abnormal ultrasounds with fetal akinesia and polyhydramnios, with one combined with fetal growth restriction. Four pregnancies with a positive prenatal ES were terminated, while five having not receiving prenatal ES continued to term. Only one infant survived 1 year old, and four passed away within 12 months. CONCLUSION: Prenatal ultrasound can detect clues that lead to the diagnosis of NM, such as reduced or absent fetal movements, polyhydramnios and extremity anomalies.

Isolated polyhydramnios: Is a genetic evaluation of value?

OBJECTIVE: To analyze the risk for genetic aberrations and pregnancy outcomes in pregnancies with isolated polyhydramnios. STUDY DESIGN: This was a retrospective study of singleton pregnancies complicated by isolated polyhydramnios that underwent genetic amniocentesis between 2016 and 2021. Clinical and laboratory data were collected and reviewed for these cases, including maternal demographics, prenatal sonographic findings, chromosomal microarray results, and pregnancy outcomes. RESULTS: A total of 94 singleton pregnancies were included. Three (3.2%) cases with chromosomal abnormalities were detected, including 2 case of trisomy 21 and 1 of 22q21.1 microdeletion. One case was diagnosed as Prader-Willi syndrome caused by maternal uniparental disomy of chromosome 15. Perinatal death occurred in 1 case with severe polyhydramnios, and was retrospectively diagnosed as Bartter syndrome. Of the 90 infants survived, two were identified to have single gene disorders after birth by whole exome sequencing. CONCLUSION: We first attempted to determine the value of exome sequencing in pregnancies with isolated polyhydramnios. Our results warrant more studies to evaluate advanced genetic testing technologies used in such pregnancies.

Fetal Rhabdomyoma Leads to Family Diagnosis of Tuberous Sclerosis Complex.

Tuberous sclerosis complex (TSC) is a multisystem genetic disorder characterized by the growth of numerous noncancerous tumors in many parts of the body. It is highly variable in clinical presentations, including a wide range of cognitive, behavioral, and psychiatric manifestations. Of all the possible manifestations, cognitive and behavioral problems are the greatest concern to parents and physicians. In this study, two fetuses were identified to have rhabdomyomas by prenatal ultrasound. Carefully inquired familial medical history revealed other symptoms of TSC such as skin lesions or psychiatric problems in family members in the two families. Both fetuses and family members with positive clinical symptoms were confirmed to carry a familial TSC2 variant. Our study indicates that fetal echocardiography is not just the evaluation of the fetal heart. When fetal cardiac rhabdomyomas are diagnosed, a full family medical history and clinical assessment for TSC in family members should be undertaken.

Megacystis in the First Trimester as an Unreported Sonographic Finding of Alveolar Capillary Dysplasia with Misalignment of Pulmonary Veins Confirmed by Whole-exome Sequencing.

A pregnant woman was revealed to have fetal univentricular heart and megacystis by a routine first-trimester ultrasound. Chorionic villus sampling with the use of karyotyping and microarray found no causative etiologies. A further investigation with whole-exome sequencing (WES) demonstrated a FOXF1 variant. Autopsy confirmed the prenatal findings, and a histological study of the lungs showed the characteristic features of alveolar capillary dysplasia with misalignment of pulmonary veins (ACDMPV). This study indicates that although ultrasound itself has no ability of the identification of pulmonary histological malformations associated with ACDMPV, the early markers of univentricular heart and megacystis might alert clinicians to consider this genetic disorder which is facilitated considerably by the increasingly used WES in prenatal diagnosis.

Prenatal diagnosis of autosomal recessive Noonan syndrome associated with biallelic LZTR1 variants presented with thick nuchal translucency and cardiac abnormalities.

Noonan syndrome (NS) is a common clinical variable disease characterized by a number of features, mainly including congenital heart defects, short stature, and a variable degree of developmental delay. This disorder is transmitted mostly in an autosomal dominant manner and is genetically heterogeneous. We report three prenatal cases of LZTR1-related recessive NS. One case had a recurrent cystic hygroma at 13 weeks gestation and the pregnancy was terminated. Two cases had an increased nuchal translucency at 12 weeks' gestation, but a normal second trimester ultrasound; both presented with hypertrophic cardiomyopathy in the third trimester. The two infants were diagnosed with NS after birth. All of the three cases had invasive genetic investigations during pregnancy, and trio exome sequencing revealed biallelic likely pathogenic or pathogenic LZTR1 variants in the fetuses. All parents were LZTR1 variant carriers. Our report further strengthens the association of LZTR1 with an autosomal recessive form of NS. The affected fetuses are more likely to have cardiac anomalies. Clarification of molecular diagnosis has important implications in these families because they carry a 25% recurrence risk.

ß-Thalassemia Trait Caused by SUPT5H Defects: Another Case Report.

We identified a novel mutation in the SUPT5H gene in a Chinese female who presented with a ß-thalassemia trait. The substitution of c.193C > T (p.Arg65*) leads to a premature stop codon on residue 65 and could be associated with haploinsufficiency. This variant was inherited from the mother who also had the asymptomatic phenotype of ß-thalassemia trait. Our case further supports the role of SUPT5H as a potential ß-globin chain production-modulating gene.

Application of real-time PCR-based multicolor melting curve with automatic analysis system in pregestational and prenatal thalassemia diagnoses.

BACKGROUND: To evaluate the value of the real-time PCR-based multicolor melting curve analysis (MMCA) with an automatic analysis system used in a mass thalassemia screening and prenatal diagnosis program. METHODS: A total of 18,912 peripheral blood samples from 9456 couples and 1150 prenatal samples were detected by MMCA assay. All prenatal samples were also tested by a conventional method. Samples with unknown melting peaks, unusual peak height ratios between a wild allele and a mutant allele, or a discordant phenotype-genotype match were further studied by using multiplex ligation-dependent probe amplification (MLPA) or Sanger sequencing. All MMCA results were automatically analyzed and manually checked. The consistency between MMCA assay and conventional methods among prenatal samples was investigated. RESULTS: Except for initiation codon (T > G) (HBB:c.2T > G), all genotypes of thalassemia inside the scope of conventional methods were detected by MMCA assay. Additionally, 27 carriers with 10 rare HBB variants, 13 with α fusion gene, 1 with a rare deletion in α globin gene, and 1 with rare HBA variant were detected by using MMCA assay. CONCLUSION: MMCA can be an alternative approach used in routine thalassemia carrier screening and prenatal diagnosis for its high throughput, sufficient stability, low cost, and easy operation.