Hyperechoic fetal bowel: The perinatal consequences

A number of publications have reported an association between the finding of hyperechoic fetal bowel on prenatal sonogram and disorders such as aneuploidy and cystic fibrosis. To define more precisely the significance of this finding, we systematically reviewed the published material on the subject. Based on a total of 357 reported cases, we documented a high prevalence of cystic fibrosis (25·6 per cent) and chromosome abnormality (12·4 per cent) associated with increased bowel echogenicity in the fetus. High rates of intrauterine growth retardation (14·9 per cent), fetal demise (9·0 per cent), and prematurity (15·3 per cent) were also found. The data were obtained from a population at high a priori risk for aneuploidy and included fetuses at 1 in 4 risk for cystic fibrosis reported in two studies. This increased the bias towards an adverse outcome. The rate of complications when a hyperechoic abdomen is noted in a low-risk fetal population has so far not been delineated. Although the high frequency of complications found is of concern and warrants investigation, extrapolation of these risk figures to a fetal population at low a priori risk may not be appropriate.     

Sonographic findings in Beckwith–Wiedemann syndrome related to H19 hypermethylation

Beckwith–Wiedemann syndrome (BWS) is an overgrowth syndrome associated with congenital malformations and tumour predisposition. BWS results from variable mutations or epigenetic modifications of imprinted genes in the 11p15 chromosomal region. We present a fetus with mild general overgrowth and bilateral enlarged echogenic kidneys with loss of the corticomedullary differentiation in which prenatal diagnosis of BWS was suspected. The rest of the fetal anatomy and the amniotic fluid volume appeared normal. After termination of the pregnancy, molecular analysis confirmed the diagnosis of BWS by showing an isolated hypermethylation of the H19 gene. Copyright © 2004 John Wiley & Sons, Ltd.     

Prenatal morphology in meckel's syndrome (with special reference to polycystic kidneys and double encephalocele)

Prenatal morphology of Meckel's syndrome was studied in five fetuses of different gestational age, that had been aborted because ultrasonography and elevated amniotic AFP-levels indicated neural tube defect. Histologically, the enlarged polycystic kidneys were completely alike with respect to the type of involvement and differed only in the severity of changes. They could be identified as type III cystic kidneys according to the classification of Potter. Proliferation of hepatic bile ducts and slight cystic dilatation of pancreatic ducts is already evident in the youngest fetus. Additional cyst formation in the epididymis was found in one of the cases. Occipital encephalocele, located within an apical occipital bone defect was always associated with a second mostly occult encephalocele protruding through a separate defect of the basal occipital squame and of the first and second vertebral arch. It is assumed that double encephalocele represents a constant finding in Meckel's syndrome, indicating a specific pattern within the disturbance of neural tube closure.     

Cystic fibrosis: selecting the prenatal screening strategy of choice

Cystic fibrosis is a serious disorder. Research into the treatment of affected individuals is in progress, but a cure is not expected in the near future. In this review, we demonstrate that prenatal screening for cystic fibrosis meets the requirements for a worthwhile screening programme. We explain the reasons that have led us to conclude that one approach (‘couple screening’) is the method of choice. The couple-based approach calls for reporting results to the couple as a unit. Only if both parents are found to be carriers is the result designated screen-positive and an amniocentesis or chorionic villus sampling offered. This offers a substantial reduction in the proportion of women with unaffected pregnancies with positive results (the false-positive rate) compared with other methods without reducing the detection of affected pregnancies. It also avoids creating a screen-positive group for which no definitive diagnosis is available. This is a problem with other screening methods. The couple method can achieve a 72% detection rate for a 0.1% false-positive rate. The screening method is simple, non-invasive, reliable, safe and reasonably cost effective. Existing programmes have shown that screening using this method is acceptable to health care professionals and patients. Setting up a national prenatal screening programme for cystic fibrosis is timely and should be implemented using the couple screening method. Copyright © 2003 John Wiley & Sons, Ltd.     

In utero therapy for fetal thoracic abnormalities

Fetal thoracic lung anomalies are rare. The specific diagnosis can be made by utilizing ultrasound, magnetic resonance imaging (MRI), and Doppler studies. Perinatal surveillance is required for large lesions and mediastinal shift regardless of the pathological diagnosis. These can cause physiological changes in the cardiovascular system with resulting hydrops. In utero therapies are variable but with no large randomized trials to compare risks and benefits. In most cases of fetal lung lesions, continued observation with postnatal therapy is the outcome. When fetal hydrops is present or impending, in utero fetal therapy is required to try to reverse that pathological course associated with fetal or neonatal death. Maternal morbidity is increased with the development of MIRROR syndrome following the presence of long-standing fetal hydrops and possible surgical procedures. Copyright © 2008 John Wiley & Sons, Ltd.     

Cornelia de Lange syndrome (CdLS): prenatal and autopsy findings

Cornelia de Lange Syndrome (CdLS) is a multisystem disorder characterized by somatic defects and mental retardation. Prenatal diagnosis of this severe condition is difficult in view of the non-specific ultrasound abnormalities. We report three cases with prenatally suspected CdLS based on the ultrasound findings as well as low PAPP-A detected on first trimester screening in one case, and the results of the autopsy and the NIPBL gene mutation analysis. Copyright © 2009 John Wiley & Sons, Ltd.