Trisomy 22 Mosaicism from Prenatal to Postnatal Findings: A Case Series and Systematic Review of the Literature.

BACKGROUND: Among aneuploidies compatible with life, trisomy 22 mosaicism is extremely rare, and only about 25 postnatal and 18 prenatal cases have been described in the literature so far. The condition is mainly characterized by facial and body asymmetry, cardiac heart defects, facial dysmorphisms, growth failure, delayed puberty, and variable degrees of neurodevelopmental delay. PROBLEM: The scattered information regarding the condition and the dearth of data on its natural history and developmental outcomes restrict genetic counseling, particularly in prenatal settings. Moreover, a prompt diagnosis is frequently delayed by the negative selection of trisomic cells in blood, with mosaicism percentage varying among tissues, which often entails the need for further testing. Purpose/topic: The aim of our work is to provide assistance in prenatal and postnatal genetic counseling by systematically delineating the current knowledge of the condition. This entails defining the prenatal and postnatal characteristics of the condition and presenting novel data from three cases, both prenatally and postnatally. Additionally, we report the developmental outcomes observed in two new patients.

The significance of meeting Dawes-Redman criteria in computerised antenatal fetal heart rate assessment.

OBJECTIVE: To investigate the significance of not meeting Dawes-Redman criteria on computerised cardiotocography in high-risk pregnancies. DESIGN: Retrospective observational study. SETTING: UK university hospital. POPULATION: High-risk pregnancies undergoing antenatal assessment. METHODS: We interrogated the database for records of computerised fetal heart rate assessment and pregnancy outcomes. MAIN OUTCOME MEASURES: Neonatal outcome and stillbirths. RESULTS: Excluding duplicate assessment in the same pregnancy, 14 025 records with complete information on the criteria of normality having been met and the outcome of the pregnancy were available. Criteria were not met for 907 records (6.46%). The gestational age of assessment was lower in the group not meeting criteria of normality. Overall, 32 stillbirths occurred in normally formed fetuses (2.28/1000). Stillbirths were more frequent in the group not meeting criteria (odds ratio [OR] 8.78, 95% CI 4.28-18.02). This finding persisted even after records with abnormally low short-term variation (STV) were excluded. The confidence intervals around the rate of stillbirth in the two groups overlapped beyond an STV of 8 ms. CONCLUSIONS: Approximately 1:16 pregnancies do not meet the criteria of normality. The criteria are not met more often at preterm gestation than at term. The risk of stillbirth was higher in the group not meeting criteria of normality, even if cases with low STV are excluded. Cases not meeting criteria should be followed up closely, unless the STV is ≥8 ms. Stillbirths still occurred in the group meeting criteria, but the rate was lower than in the general population.

De novo RANBP2 variant in a fetal demise case with cerebral intraparenchymal hemorrhage.

Fetal intracranial hemorrhage (ICH) may result from a wide array of causes, either associated with maternal or fetal risk factors. In the last decade, monogenic causes of susceptibility to fetal ICH have been described, in particular in association with COL4A1 and COL4A2 genes. A peculiar form of ICH is acute necrotizing encephalitis (ANE), which is characterized by a rapid-onset severe encephalopathy following an abnormal inflammatory response to an otherwise banal infection. It usually affects healthy children and it is thought to be multifactorial, with a genetic predisposition. RANBP2 gene has been extensively associated with ANE susceptibility. We hereby present a unique case of a 42-year-old secundigravida with intrauterine fetal demise at 35 weeks of gestation. Trio-based whole-exome sequencing performed on both parents and fetal DNA showed a de novo likely pathogenic variant in the RANBP2 gene on 2q13. At the fetal autopsy, subtentorial hematoma and cerebral intraparenchymal hemorrhage were present. We speculate that this might be a new phenotypic presentation of RANBP2-associated disease. However, more similar fetal cases need to be reported in order to reinforce this hypothesis.

Is mid-gestational uterine artery Doppler still useful in a setting with routine first-trimester pre-eclampsia screening? A cohort study.

OBJECTIVE: To evaluate whether routine mid-gestational uterine artery Doppler (UtAD) modifies the risk for preterm pre-eclampsia after first-trimester combined pre-eclampsia screening. DESIGN: Retrospective cohort study. SETTING: London Tertiary Hospital. POPULATION: A cohort of 7793 women with singleton pregnancies, first-trimester pre-eclampsia screening using the Fetal Medicine Foundation (FMF) algorithm and UtAD pulsatility index (PI) assessment at the mid-gestation ultrasound. METHODS: Pregnancies were divided into four groups: high risk in both trimesters (H1 H2 ), high risk in the first but not in the second trimester (H1 L2 ), low risk in the first but high risk in the second trimester (L1 H2 ) and low risk in both trimesters (L1 L2 ). MAIN OUTCOME MEASURES: Small for gestational age (SGA), hypertensive disorders of pregnancy (HDP) and stillbirth. RESULTS: In this cohort, 600 (7.7%) and 620 (7.9%) women were designated as being at high risk in the first and second trimesters, respectively. Preterm pre-eclampsia was more prevalent in the H1 L2 group (4.5%) than in women considered at low risk in the first trimester (0.4%, p < 0.0001). The prevalence of preterm pre-eclampsia in the L1 H2 group (3.3%) was significantly lower than that in women considered at high risk in the first trimester (7.0%, p = 0.0076), and was higher than that observed in the L1 L2 group (0.2%, p < 0.0001). The prevalence of SGA and term HDP followed similar trends. CONCLUSIONS: Pre-eclampsia risk after first-trimester FMF pre-eclampsia screening may be stratified through mid-gestational routine UtAD assessment. Pregnancy care should not be de-escalated for low mid-gestational UtAD resistance in women classified as being at high risk in the first trimester. The escalation of care may be justified in women at low risk but with high mid-gestational UtAD resistance.

SIMPSON-GOLABI-BEHMEL syndrome type 1: How placental immunohistochemistry can rapidly Predict the diagnosis.

INTRODUCTION: Glypican-3 (GPC3) is an oncofetal protein involved in cellular signaling, strongly expressed in the placenta, absent or diminished in postnatal life, but often increased in human malignancies. Germline loss-of-function variants of GPC3 gene are associated with Simpson-Golabi-Behmel syndrome type 1 (SGBS1), a rare recessive X-linked overgrowth disease characterized by typical facial features, congenital abnormalities, and an increased risk of developing childhood cancers. METHODS: A clinical suspicion of SGBS1 was postulated for a newborn with prenatal history of overgrowth and polyhydramnios, presenting with neonatal weight and length >99th percentile, coarse facies, iris and retinal coloboma, supernumerary nipples, and splenomegaly. While waiting for whole-genome sequencing (WGS) results, we investigated placental GPC3 immunohistochemical expression in the proband, in three additional cases of SGBS1, and disorders commonly associated with fetal macrosomia and/or placentomegaly. RESULTS: WGS in the proband identified a likely pathogenic maternally inherited missense variant in GPC3: c.1645A > G, (p.Ile549Val), and GPC3 immunohistochemistry demonstrated full-thickness loss of stain of the placental parenchyma. The same pattern ("null") was also present in the placentas of three additional cases of SGBS1, but not in those of unaffected controls. DISCUSSION: Immunohistochemical expression of GPC3 in the placenta is highly reproducible. Our findings showed that a "null pattern" of staining is predictive of SGBS1 and represents a valuable aid in the differential diagnosis of fetal macrosomias, allowing targeted genetic testing and earlier diagnosis.

Clinical Correlates of Placental Pathologic Features in Early-Onset Fetal Growth Restriction.

INTRODUCTION: The purpose of this study was to evaluate the association between placental pathologic features of maternal (MVM) or fetal (FVM) vascular malperfusion and clinical characteristics, sonographic findings and neonatal outcome in a cohort of pregnancies complicated by early-onset (diagnosed before 32 weeks of gestational age) fetal growth restriction (FGR). METHODS: A prospective cohort study included 250 singleton early-onset FGR pregnancies diagnosed, followed up and delivered at a single center. Placental pathologic lesions were classified according to standard recommendations. Logistic regression and Cox analysis were used to evaluate outcomes adjusting for confounders. RESULTS: Overall features of severe placental MVM and FVM were observed in 29.6% (74/250) and 12.8% (32/250) of the subjects, respectively. Severe placental MVM lesions were more common among subjects with umbilical artery Doppler Pulsatility Index >95th than ≤95th percentile (50/120 as opposed to 24/130, Adj odds ratio [OR] = 3, 95% CI = 1.6-5.4) and Cerebroplacental ratio <5th than ≥5th percentile (48/115 as opposed to 26/135, Adj OR = 2.7, 95% CI = 1.5-4.9). Mean time from FGR diagnosis to delivery was shorter among subjects with severe MVM (25.5 days, 95% CI = 20.6-30.2, Adj. OR = 1.9, 95% CI = 1.9, 95% CI = 1.4-2.5) when compared to both those with mild/moderate MVM (36.5 days [95% CI = 27.2-45, p = 0.04]) or no MVM (39.4, 95% CI = 35.4-43.4, p < 0.001). Finally, severe FVM was associated with an increased risk of perinatal/neonatal death or severe brain lesions (9/28 in subjects with perinatal/neonatal death/brain lesions as compared to 23/222 in controls, Adj OR = 3, 95% CI = 1.05-8.6) or severe adverse neonatal outcomes (13/46 in subjects with severe adverse outcome as compared to 19/204 among controls, Adj OR = 3.2, 95% CI = 1.2-8.5). CONCLUSIONS: In early-onset FGR, placental pathologic features of MVM and FVM are, in different regards, associated to severity of clinical picture, abnormal Doppler markers of placental and fetal circulation and of neonatal outcome, respectively.