NT >99th centile and cystic hygroma: Which diagnosis, which management and outcome.

OBJECTIVES: To evaluate the prevalence of chromosomal anomalies in fetuses affected by increased nuchal translucency(iNT >99Th centile), cystic hygroma (CH) and cases progressing to fetal hydrops (NIHF) in order to correlate this result to prognosis and perinatal fetal outcomes, improving patient's counseling. METHODS: From January 2020 to December 2023, first trimester screening according to FMF criteria were performed in "Maternal fetal medicine Unit" of Foggia's hospital. We studied and collected clinical data of fetuses affected by nuchal translucency >99th centile (iNT), CH and cases progressing to Fetal Hydrops (non-immune fetal hydrop, NIFH). In these selected cases, we evaluated fetal Karyotype to demonstrate the presence of chromosomal abnormalities, associated to fetal structural anomalies and different pregnancy outcome. RESULTS: We have evaluated 45 cases of iNT, CH, and NIFH, identified by ultrasound during first trimester screening. Of these 45 pregnant women, four were lost to follow-up. Of the 41 pregnancies, 20 cases (48.8%) delivered at our division with newborns discharged in good health. Of the 21 patients (51.2%) who miscarried, only two miscarried spontaneously; the other 19 decided on a medical termination of pregnancy (MTP). The 19 patients who decided for MTP showed genetic abnormalities and/or malformation. The 20 cases of fetuses discharged as healthy newborns were enrolled with the following diagnoses: 5 had a diagnosis of CH (20% of cases), 1 case of NIFH (5% of cases), and 14 of iNT (75% of cases). All these fetuses had a normal karyotype and no major malformations. CONCLUSIONS: Isolated CH diagnosis is more frequent than described in Literature (5 cases out of 12: 41.7%) and their prognosis are better than previously described, with the same outcomes of fetuses with iNT without associated anomalies. The possibility of early diagnosis of chromosomal anomalies, associated malformations or the evolution into hydrops is essential for a complete consultation.

Anesthetic Management of a Massive Cystic Hygroma of the Neck in a Neonate.

Cystic hygroma of the neck, a congenital benign tumor of the lymphatic system, is a potential cause of neonatal airway obstruction leading to stridor. Meticulous airway evaluation, case appropriate preparation, and use of advanced technology, including videolaryngoscope and ultrasonography, can facilitate the safe management of the difficult airway.

Prenatal diagnosis of Noonan syndrome in a set of monozygotic twins- a case report.

BACKGROUND: We report a pair of dichorionic diamniotic (DCDA) twin pregnancy affected by Noonan syndrome (NS) with a novel mutation of LZTR1 determined by genetic analysis. CASE PRESENTATION: A pregnant woman with monozygotic twins (DCDA) at 12 + 2 weeks gestation was referred to our center. This was her second pregnancy following a previous delivery of a healthy infant. Nuchal translucency of two fetuses was 11.2 mm (CRL 62.0 mm) and 6.9 mm (CRL 62.1 mm) respectively. Ultrasound examination indicated cystic hygroma and hypoplastic ear. The couple was not consanguineous, and both had normal phenotype. Familial hereditary disease was also excluded. Under ultrasound guidance, 30 mg of chorionic villi was obtained for karyotyping, quantitative fluorescent polymerase chain reaction (QF-PCR), chromosomal microarray analysis(CMA), and Trio-whole-exome sequencing(WES) examination. We used the "target region capture and sequencing" for WES, and the BWA (Burrows Wheeler Aligner) Multi-Vision software package for the data analysis. The results of all these tests were normal except WES detected a c.427 A > G mutation in the exonic region of the LZTR1 gene and a p. Asn143Asp novel heterozygous mutation associated with NS in this pair of twins. In addition, WES suggested that the mutation in the twin fetuses originated from the mother. When the mother got the genetic test report, she came to our fetal medicine department for genetic counseling and she declined the appointment with a clinical geneticist. The couple opted to terminate the pregnancy. Because the patient did not choose to terminate the pregnancy at our hospital, we were unable to take further examination. With the help of colleagues in another hospital, photos of the fetuses were taken. Compared with the prenatal ultrasound results, the appearance of the "cystic hygroma" and "hypoplastic ear" was consistent with the ultrasound. The couple were depressed after knowing this pathogenic result and although we advised the mother to take further investigation, they refused. CONCLUSION: The mutant locus might be incompletely dominant, which led to an abnormal fetal phenotype such as cystic hygroma and hypoplastic ear.

First-trimester septated cystic hygroma, marked non-immune fetal hydrops, 45,X and coarctation of the aorta with neonatal survival.

Marked first-trimester nonimmue hydrops fetalis and 45,X with neonatal survival.

Does the Presence of Extended Jugular Lymphatic Sacs Add More Risk to Nuchal Thickness for Genetic and Structural Abnormality?

Background: The risks added by extended jugular lymphatic sacs (EJLS) to increased nuchal translucency (NT) including genetic and structural abnormalities and pregnancy outcomes have not been previously investigated, which this study aims to investigate. Methods: The data of 155 singleton pregnancies with increased fetal NT (≥95th percentile) of these 20 with fetal EJLS were evaluated retrospectively. Patients were stratified according to NT thickness such that ≥95th percentile - 3.5 mm, 3.6-4.4 mm, 4.5-5.4 mm, 5.5-6.4 mm, ≥6.5 mm, and grouped according to the presence of EJLS. Pregnancy outcomes, genetic and structural abnormalities were assessed by comparing EJLS with non-EJSL cases (n-EJLS). Results: Associated with NT, the incidence of the presence of EJLS increased with NT, from 4.5% at the ≥95th percentile - 3.5 mm to 30.8% when NT ≥5.5 mm. In the n-EJLS group, the proportion of fetuses with structural and genetic abnormalities increased as the measurement of NT increased. This correlation was not observed in the EJLS group. Compared to n-EJLS, cases with EJLS had a higher rate of fetal structural (38.5% vs. 75%, P = 0.003) and genetic (18.5% vs. 45%, P = 0.005) anomalies and a lower term live birth rate (59.3% vs. 15%, P < 0.001). Conclusion: The increasing rate of EJLS was seen as NT increased. Compared to n-EJLS, the EJLS cases had a higher rate poor pregnancy outcomes and fetal genetic and structural abnormalities.

Prenatal Genetic Diagnosis of Fetal Cystic Hygroma: A Retrospective Single-Center Study from China.

Fetal cystic hygroma (CH) is associated with poor prognosis and chromosomal anomalies. Recent studies have suggested that the genetic background of affected fetuses is essential for predicting pregnancy outcomes. However, the detection performance of different genetic approaches for the etiological diagnosis of fetal CH remains unclear. In this study, we aimed to compare the diagnostic efficiency of karyotyping and chromosomal microarray analysis (CMA) in a local fetal CH cohort, and tried to propose an optimized testing strategy that may help improve the cost-effectiveness of disease management. We reviewed all pregnancies that underwent invasive prenatal diagnosis between January 2017 and September 2021 at one of the largest prenatal diagnostic centers in Southeast China. We collected cases identified by the presence of fetal CH. Prenatal phenotypes and laboratory records of these patients were audited, collated, and analyzed. The detection rates of karyotyping and CMA were compared, and the concordance rate of these two methods was calculated. A total of 157 fetal CH cases were screened from 6,059 patients who underwent prenatal diagnosis. Diagnostic genetic variants were identified in 44.6% (70/157) of the cases. Karyotyping, CMA, and whole-exome sequencing (WES) identified pathogenic genetic variants in 63, 68, and 1 case, respectively. The Cohen's κ coefficient between karyotyping and CMA was 0.96, with a concordance of 98.0%. Of the 18 cases in which cryptic copy number variants <5 Mb were detected by CMA, 17 were interpreted as variants of uncertain significance, and the remaining cases were interpreted as pathogenic. Trio exome sequencing revealed a pathogenic homozygous splice site mutation in the PIGN gene in a case undiagnosed by CMA and karyotyping. Our study demonstrated that chromosomal aneuploidy abnormalities are the main genetic cause of fetal CH. Based on this, we recommend karyotyping combined with rapid aneuploidy detection as a first-tier approach for the genetic diagnosis of fetal CH. WES and CMA could improve the diagnostic yield when routine genetic tests fail to determine the cause of fetal CH.

Prenatal diagnosis of cystic hygroma cases in a tertiary centre and retrospective analysis of pregnancy results.

The aim of this study is to retrospectively examine invasive diagnostic methods, structural anomalies accompanying cystic hygroma, and pregnancy outcomes in cystic hygroma cases admitted to a tertiary centre. The population of the study consisted of 29 live foetuses with cystic hygroma in the foetal neck only in the first or second trimester. In the study, pregnant women who applied to our centre were included. Amniocentesis or chorionic villus sampling was performed for genetic analysis according to the weeks of the pregnant women who were diagnosed with cystic hygroma by ultrasound examination by two clinicians experienced in foetal anomaly. Of the pregnant women included in the study, 10 had normal karyotype, 12 had abnormal karyotype and 13 had structural abnormality. It is very important to provide genetic counselling to the families of foetuses with cystic hygroma with a multidisciplinary team approach consisting of neonatologists, paediatric surgeons and experienced sonographers. Implications for rehabilitationWhat is already known on this subject? Cystic hygroma, also known as cystic lymphangioma, is a congenital cystic malformation often seen in the first trimester, which occurs in the foetal neck due to the failure of the connections between the cervical lymphatic vessels and the jugular venous system to develop normally. Cystic hygroma may be isolated, but highly associated with foetal aneuploidy, hydrops fetalis, abnormal foetal nuchal translucency.What do the results of this study add? Invasive prenatal diagnostic tests (CVS or amniocentesis) should be performed in all patients with cystic hygroma, as cystic hygromas can be diagnosed by first trimester foetal genetic sonogram screening and are largely accompanied by chromosomal abnormalities.What are the implications of these findings for clinical practice and/or further research? In foetuses with cystic hygroma, foetal karyotyping, detailed sonography and their documentation, genetic counselling is important to families of cystic hygroma foetuses with a multidisciplinary team approach consisting of neonatologists, paediatric surgeons and maternal foetal medicine specialists, since there is a high risk for aneuploidy and foetal malformation.

Outcome of 45,X fetuses with cystic hygroma: A systematic review.

This objective of this systematic review was to estimate live birth rate and explore prognostic indicators in fetuses with 45,X karyotype and a posterior cystic hygroma (CH). Electronic databases were searched and studies reporting pregnancy outcomes (termination, spontaneous abortion, demise, or live birth) for fetuses with 45,X karyotype and a CH diagnosed on ultrasound were included. For cases of survival, CH characteristics, presence of hydrops fetalis, or concomitant anomalies, delivery details, and postnatal outcomes were summarized. A total of 95 studies, including 535 cases, met inclusion criteria: 285 (53.3%) pregnancies were terminated, 72 (13.5%) had spontaneous abortion or demise, 164 (30.7%) had unspecified pregnancy failure, and 14 (2.6%) were live births. Among live births with data available, all CH measured 2-7 cm, more than half were septate, and almost all regressed in size or eventually disappeared. Hydrops fetalis was noted in five cases. Of the eight live births with neonatal outcomes available, three neonates died shortly after birth and five survived past the neonatal period. This review suggests that diagnosis of CH in a 45,X fetus is associated with an estimated live birth rate of 2.6%, but only 1% survive to infancy. Prognosis appears to improve with CH regression.

Euploid First-Trimester Cystic Hygroma: A More Benign Entity than Previously Thought?

OBJECTIVE: Studies summarizing the outcome of first-trimester septated cystic hygroma are generally based on small studies or from multiple centers with limited ascertainment. We reviewed the natural history of a large cohort of such cases from a single tertiary referral center, with the aim being to establish contemporary outcome data, particularly in the setting of normal karyotype. METHODS: A retrospective cohort study from 2007 to 2017 was conducted at a single tertiary referral prenatal diagnosis center. Data were analyzed from a prospectively collated fetal anomaly database. Search terms were "increased nuchal translucency (NT)," "cystic hygroma," and "septated cystic hygroma." All cases were confirmed to have NT >3 mm with septations. Cases of simple increased NT without septations were excluded. RESULTS: During the study period, over 110,000 pregnancies were delivered at our center, resulting in 410 cases of septated cystic hygroma diagnosed prior to 14 weeks' gestation. Pregnancy outcome was obtained in 99% (405/410) of cases, with detailed pathology outcome available in 92% (378/410). A total of 87% (351/405) underwent invasive prenatal testing, and postnatal chromosome status was established in further 27 cases. A total of 61% (230/378) had abnormal chromosomal status. Of the 39% (148/378) with normal chromosomal status, only 13% (19/148) had a significant structural fetal abnormality, which included 7 cardiac and 12 noncardiac abnormalities. Overall, the perinatal loss was 62% (253/405). The total survival rate in the setting of euploid cystic hygroma without structural abnormality was 84% (108/129). CONCLUSIONS: Counseling regarding outcomes in the setting of first-trimester septated cystic hygroma initially focuses on the strong likelihood of an abnormal karyotype, which occurs in 61% of cases. However, once fetal chromosomal abnormality is excluded, our results demonstrate only a 13% incidence of major structural fetal abnormality, which appears significantly less than previously reported. Normal fetuses have a 77% survival rate. These data represent the largest single-center study of first-trimester cystic hygroma with complete outcome data and therefore will be useful for contemporary patient counseling. Such counseling can be more positive than previously expected, once chromosomal abnormality is first excluded.

Neu-Laxova syndrome presenting prenatally with increased nuchal translucency and cystic hygroma: The utility of exome sequencing in deciphering the diagnosis.

Neu-Laxova syndrome (NLS) is a lethal autosomal recessive microcephaly syndrome associated with intrauterine growth restriction (IUGR) and multiple congenital anomalies. Clinical features include central nervous system malformations, joint contractures, ichthyosis, edema, and dysmorphic facial features. Biallelic pathogenic variants in either the PHGDH or PSAT1 genes have been shown to cause NLS. Using exome sequencing, we aimed to identify the underlying genetic diagnosis in three fetuses (from one family) with prenatal skin edema, severe IUGR, micrognathia, renal anomalies, and arthrogryposis and identified a homozygous c.1A>C (p.Met1?, NM_006623.3) variant in the PHGDH gene. Loss of the translation start codon is a novel genetic mechanism for the development of NLS. Prenatal diagnosis of NLS is challenging and few reports describe the fetal pathology. Fetal neuropathologic examination revealed: delayed brain development, congenital agenesis of the corticospinal tracts, and hypoplasia of the hippocampus, cerebellum and brainstem. Each pregnancy also showed increased nuchal translucency (NT) or cystic hygroma. While NLS is rare, it may be a cause of recurrent increased NT/cystic hygroma. This finding provides further support that cystic hygroma has many different genetic causes and that exome sequencing may shed light on the underlying genetic diagnoses in this group of prenatal patients.