Prenatal diagnosis--a compilation of diagnosed conditions

Prenatal Diagnosis of Lethal Shor-limbed Dwartism

Nine of 23 established types of short-limbed dwarfism are always incompatible with life. Current state-of-the-art ultrasonic equipment and techniques combined with the establishment of longitudinal growth curves for fetal long bones have made possible the early prenatal diagnosis of lethal skeletal dysplasias. In addition to significantly shortened and/or bowel femurs, features include hydramnios, fetal hydrops, and protuberant fetal abdomen, all easily identifiable with ultrasound. The availability of early prenatal diagnosis of these skeletal dysplasias has placed increased importance on early ultrasonic evaluation of at-risk populations, providing an additional diagnostic parameter to complete the genetic workup.

Sonographic Diagnosis of Antley-Bixler PORD-Type Syndrome

Antley-Bixler syndrome (ABS)—consisting of ABS type 1 (skeletal only) and ABS type 2, associated with cytochrome 450 mutations and P450 oxidoreductase deficiency (PORD-ABS)—is a heterogeneous syndrome with a constellation of skeletal deformation findings that classically include skull, facial, and appendicular defects. The hallmarks of ABS type 1 include craniosynostosis, midface hypoplasia, radiohumeral/radioulnar synostosis, arachnodactyly, bowing of the femur, congenital fractures, and choanal atresia. ABS has historically been identified at newborn or childhood examination using radiographic, computed tomography, or stillbirth autopsy. However, in recent years, antenatal ultrasonography has identified craniosynostotic conditions in utero. We present a case of PORD with the ABS phenotype diagnosed by sonography in utero at an early gestation (13–16 weeks), which included mutations in the POR gene. Sonographers, sonologists, and perinatologists aware of the diversity of this rare condition will be well prepared to raise the suspicion of Antley-Bixler PORD-type syndrome.

Fetal anomalies and the pediatrician

The role of the pediatrician begins when the antenatal diagnosis of a congenital anomaly has been confirmed in a high-risk perinatal center. The pediatrician contributes in establishing the prognosis and to discuss the best therapeutic possibilities based upon his own experience and the literature. The pediatrician plays an important role in the informing of the parents, particularly when the malformation is correctable. He will provide them with a complete explanation about the care of the baby, possible complications, and the prognosis. The parents meet the medical staff, see the place where their child will be treated after birth, gain confidence, and prepare the best possible mother-infant and father-infant links. The delivery should be planned in a high-risk perinatal center to avoid the postnatal transportation of a sick newborn infant as well as the separation of the infant from the mother. A planned delivery is essential to permit the pediatrician to prepare and execute an early adapted-to-the-malformation resuscitation and prompt surgery in the hope of reducing mortality and morbidity. After birth, the pediatrician plays a role not only in the pre- and postoperative care, but also in supporting the parents and facilitating their investment in the sick baby. The antenatal diagnosis permits the pediatrician and the surgeon to prepare and optimize the care of the newborn and allows the parents to anticipate the mourning of the imagined infant, providing them time to accept the diagnosis and the sick baby before the birth.

Fetal echocardiography. V. M-mode measurements of the aortic root and aortic valve in second- and third-trimester normal human fetuses

The aortic root dimension and aortic valve excursion of 43 normal fetuses were recorded with M-mode echocardiography and the measured dimensions correlated with noncardiac measurements (biparietal diameter, head circumference, abdominal circumference, and femur length) and cardiac measurements (diastolic biventricular inner dimension, diastolic left ventricular internal dimension, and mitral valve excursion). The correlation coefficients for the aortic root dimension ranged between 0.87 and 0.95, while those for the aortic valve excursion ranged between 0.78 and 0.87. Regression analysis demonstrated that the best fit of the data was a linear model from which the 5% and 95% confidence limits were computed for individual predictions of aortic root dimension and aortic valve excursion from noncardiac and cardiac measurements.

Genetic screening of prospective parents and of workers: some scientific and social issues

Genetic screening programs are based on assumptions and values that reflect the history of racial and social eugenics in the United States and Europe. They stigmatize individuals by shifting the focus from social, economic, and political decisions that affect the health of prospective parents, newborns, and workers to "bad genes," that is, intrapersonal factors that are given the status of "causes" of disease. Prenatal screening, at best, can help the relatively few individuals who know that their future children are at risk for a particular inherited disease or disability; it has little positive value for the average person. Workplace genetic screening has not been shown to reduce occupational disease, but it has led to employment discrimination and has drawn attention away from controlling exposures to toxic chemicals in the workplace.

Maternal serum alpha-fetoprotein screening for neural tube defects. Report of a combined study in Germany and short overview on screening in populations with low birth prevalence of neural tube defects

The basis of maternal serum alpha-fetoprotein (AFP)-screening for neural tube defects is discussed. A report is given of a large scale screening study in the Federal Republic of Germany combining the experiences in Giessen and Hannover on over 50,000 pregnant women, about evenly distributed among both centers. Published and known forthcoming data from other low incidence populations, particularly of European countries, are reviewed briefly. The conclusion is reached that general screening could effectively be instituted and in the final result should also be cost-beneficial.

Fetal echocardiography. IV. M-mode assessment of ventricular size and contractility during the second and third trimesters of pregnancy in the normal fetus

M-mode echocardiographic examination of the right and left ventricles was performed on 82 normal fetuses between 18 and 41 weeks of gestation. The diameter of the right and left ventricles correlated with the biparietal diameter. The right/left ratio of the ventricular diameters remained constant (1:1) throughout gestation. Fractional shortening and mean circumferential shortening of both ventricles were independent of gestational age. The data presented in this paper will allow the clinician to evaluate abnormal fetal conditions that might affect cardiovascular structure and/or function.

Antenatal ultrasound diagnosis of fetal malformations: possibilities, limitations and dilemmas

The antenatal ultrasound diagnosis of fetal abnormalities in 150 fetuses over the period 1975-early 1983 is reported. The perinatal outcome of the whole series has been assessed. The most frequently encountered malformations involved the central nervous system (34.9%), the nephro-urological system (17.2%), and the gastro-intestinal tract, abdominal wall and diaphragm (17.1%). Neonatal findings in incompletely explained polyhydramnions, fetal hydrops, and severe intrauterine growth retardation are also commented upon. Numerical chromosomal abnormalities were present in at least 13.3% of the malformed fetuses. The accuracy of the antenatal ultrasound diagnosis in a defined subgroup with congenital malformations resulting in perinatal death was analysed: in 76.9% one (or more) malformations were correctly diagnosed or relevant information was obtained. Comment is made on the obstetrical management and its inherent dilemmas, with appropriate references to the literature. Antenatal ultrasound, together with complementary techniques, can reach an acceptable level of accuracy, but associated anomalies may be missed. Groups for which there are different prognoses can be assessed, and serve as a guideline in perinatal management. Ethical attitudes, psychological aspects, and the possible promises of fetal treatment are briefly discussed.

The results of one thousand consecutive prenatal diagnoses

From 1976 to 1982, prenatal diagnosis was performed on more than 1,000 patients at the Richland Memorial Hospital. This report analyzes the experience of our unit with the first 1,000 consecutive studies. The integration of geneticist and clinician is stressed. A total of 77.7% of referrals were because of maternal age with the next most common indication being a prior child with a neural tube defect. There were 18 chromosomal abnormalities discovered, and no cases of open neural tube defect were detected. In all cases of elective termination of pregnancy in which follow-up was possible, the diagnosed abnormality was confirmed.

Prenatal diagnosis of lethal osteogenesis imperfecta (OI) by ultrasonography

Ultrasonography was performed during the second trimester (17 weeks) in a pregnancy at risk for osteogenesis imperfecta congenita (OI). The scan showed that the femur was short, bent and dense. Radiologic examination of the fetus after interruption of pregnancy showed typical X-ray changes of OI.

Prenatal ultrasound detection of humero-radial synostosis in a case of Antley-Bixler syndrome

The Antley-Bixler syndrome is characterized by multiple skeletal fusions including humero-radial synostosis, anterior bowing of the femora, cardiac and renal malformations and a high incidence of early postnatal lethality. In the pregnancy of a mother who had previously given birth to a child with the Antley-Bixler syndrome, prenatal ultrasound diagnosis was performed at 17 and 20 weeks. Fixed flexion of about 80 degrees in both elbows was seen together with humero-radial synostosis and bowing of the ulnae. The fetus performed jerky craniocaudal movements in its shoulders, but did not, during five hours of real-time observation, move at all in the elbows. Mild anterior bowing of the femora was also observed. The pregnancy was terminated at 21 weeks, and radiological examination of the female fetus confirmed the above mentioned findings including complete bilateral humero-radial synostosis. She also had cardiac and renal malformations. An ultrasound diagnosis of syndromes which have humero-radial synostosis as one feature is possible. Immobility and flexion in the elbows during a long period is probably the essential diagnostic finding.