PRENATAL DIAGNOSIS OF CYSTIC HYGROMA AND CHORIOANGIOMA IN THE WOLF-HIRSCHHORN SYNDROME

We report the prenatal diagnosis of Wolf-Hirschhorn syndrome (4p –) in a 24-week-old fetus. Echographic features included cystic hygroma, a complex heart defect with right ventricular hypoplasia, and a large placental chorioangioma. We suggest that chorioangioma may be associated with chromosomal imbalance and that systematic careful morphologic examination of the fetus and karyotyping of any pregnancy in which large chorioangioma is detected is advisable. Jugular lymphatic obstruction sequence has not been reported so far in association with 4p– syndrome.     

Proliferation kinetics in native chorionic villus cells

In accordance with observations by other groups direct CVS preparations reveal only a few mitoses, whereas semi-direct cultures (overnight incubation) give good results. By monitoring the BrdU uptake with an immunological method, a delay in the proliferation activity in native villi could be observed up to 7 h after biopsy.     

Prenatal diagnosis of tetrasomy 47,XY, + i(12p) confirmed by in situ hybridization

A case of tetrasomy i(12p) detected prenatally is reported. The patient, a black, 33-year-old G3P2002 at 24 weeks' gestation with an unremarkable family history presented herself for prenatal care. Ultrasound examination showed a fetus with diminished femoral and humeral lengths, and hydramnios. A level II scan confirmed the presence of an omphalocele. Amniocentesis at 31 weeks showed 47,XY, + i(12p) karyotype. An infant with multiple congenital anomalies was delivered at 34 weeks. The infant died after 5 h. Genetic and ultrasonographic examinations in the third trimester were helpful in the investigation of this fetus with multiple congenital anomalies. The careful, complete team counselling afforded by this approach enabled the mother and family to be well adjusted to the strong possibility (and subsequent reality) of an abnormal infant.     

Chromosome 18 analysis by fluorescence in situ hybridization (fish) in human blastomeres of abnormal embryos after in vitro fertilization (ivf) attempt

We performed fluorescence in situ hybridization (FISH) with a chromosome 18-specific probe on human abnormal cleaved embryos, fertilized either by two spermatozoa and exhibiting three pronuclei (3 PN) or normally fertilized and exhibiting two pronuclei (2 PN) with subsequent severe fragmentation and/or blocking. The aim of the study was to evaluate the incidence of chromosome 18 anomalies among these embryos, in order to evaluate the FISH efficiency on such material and to obtain more precise and complete data than those obtained with classical cytogenetic analysis. For the 3 PN cleaved embryos, FISH confirmed the frequent regulation towards diploidy (25 per cent) and the high frequency of mosaics (53 per cent). For the 2 PN blocked or damaged embryos, FISH permitted chromosome evaluation, which was otherwise impossible with classical cytogenetic techniques: we also found a high mosaic frequency (45 per cent) with these embryos. If this frequency were the same for normally developing embryos, it would be a major obstacle to the reliability of either chromosomal or genetic preimplantation diagnosis.     

Cardiac flow after fetal blood sampling in normally grown and growth-retarded fetuses

The objective of this study was to evaluate the effect of fetal blood sampling on cardiac flow velocity waveforms. Flow velocity waveforms were measured from the ascending aorta and pulmonary artery immediately before and after fetal blood sampling in 29 normally grown and 12 growth-retarded fetuses. The latter group was characterized by abnormal Doppler indices in the umbilical artery and middle cerebral artery suggestive of uteroplacental insufficiency as the causative factor of the impaired growth. The flow velocity parameters studied were the peak velocity, the time to peak velocity, and the left and right cardiac output and their ratio. In normally grown fetuses, the peak velocity and right and left cardiac output values increased significantly after fetal blood sampling, while no significant changes were observed in the other indices considered. The gestational age at the time of the procedure was positively related to the amplitude of these changes. In growth-retarded fetuses, fetal blood sampling did not induce any significant increase in cardiac output or peak velocities, while in more than 50 per cent of the fetuses these Doppler indices decreased. The amplitude of the decrease was significantly related to the severity of acidosis in the umbilical vein. In conclusion, the cardiac haemodynamic response to fetal blood sampling differs between normally grown and growth-retarded fetuses. This difference may explain the higher rate of complications occurring in the latter group of fetuses after blood sampling.     

Methylenetetrahydrofolate reductase deficiency: Prenatal diagnosis and family studies

Prenatal diagnosis of methylenetetrahydrofolate reductase (MTHFR) deficiency and family studies were performed because of a severely affected first child in this family. The fetus at risk was found to be heterozygous as confirmed by the enzymatic activity assay performed several times after birth. In the father, MTHFR activity was normal in lymphocytes and decreased in fibroblasts, whereas in the asymptomatic mother, the activity was not detectable in fibroblasts and was very low in lymphocytes. The absence of any clinical symptoms in the mother despite a clear MTHFR deficiency and hyperhomocystinemia emphasizes the heterogeneity of this disease.     

Do racial differences exist in second-trimester maternal hCG levels? a study of 23 369 patients

In Down syndrome screening by maternal serum human chorionic gonadotropin (hCG) determination at 15, 16, 17, and 18 weeks of gestation, we prospectively examined 23 369 sera from white (21 549), North African (970), black African (525), and Asian (325) patients. When expressed as multiples of the median (MOM), no difference was observed between white, North African, and black African patients. However, higher serum hCG concentrations were noted in Asians, for whom we therefore recommend correction of hCG values before calculation of the risk of Down syndrome.     

Prenatal sonographic appearance of foramina parietalia permagna

Foramina parietalia permagna (FPP) is an extremely uncommon congenital defect, inherited as an autosomal dominant condition. Its characteristics are two symmetrical orifices in the parietal bones (not of fixed size) on both sides of the midline. This defect does not affect either the psychic or the physical development of the affected person. This paper describes the sonographic appearance of FPP in utero as an enlargement of the posterior fontanelle.     

Elevated mid-trimester hCG and maternal lupus anticoagulant

An association is described between women with lupus anticoagulant and abnormal prenatal serum screening results. Three cases of positive second-trimester serum screening for Down syndrome, with karyotypically normal fetuses, in women demonstrated to have lupus anticoagulant are presented. Serum screening positivity was principally due to a disproportionately elevated maternal serum human chorionic gonadotrophin (hCG) level. In each case, early, severe intrauterine growth restriction was documented, with only one fetus surviving the neonatal period. As maternal lupus anticoagulant may have a profoundly adverse effect on the course of pregnancy, we suggest that an elevated hCG level on prenatal screening prompt consideration of maternal lupus anticoagulant testing if ultrasonography demonstrates an otherwise normal singleton gestation and the fetal karyotype is normal.