Structural chromosome anomalies in congenital diaphragmatic hernia

Prenatal diagnosis of congenital diaphragmatic hernia in a McFadden Kalousek type 2 triploid fetus

Triploidy is characterized by an extra haploid set. We report a rare case of a prenatally diagnosed digynic type (McFadden/Kalousek type 2) triploid fetus with congenital diaphragmatic hernia (CDH). Prenatal ultrasonographic examination allows reliable detection of CDH and it is therefore of great importance for proper parental counselling, as well as performing fetal karyotype for associated chromosomal anomalies.

First-year mortality rates for selected birth defects, Hawaii, 1986-1999

Birth defects have been the leading cause of infant death in the United States for over the last decade. However, there is little population-based data on the first-year mortality rates for many specific birth defects and the factors that may affect these mortality rates. This investigation examined the first-year mortality rates for 54 selected birth defects of various organ systems in Hawaii during 1986-1999 using data from a population-based birth defects registry and evaluated the impact of the presence of chromosomal abnormalities and other structural birth defects and the year of delivery on the mortality rates. Mortality rates varied widely by defect, being highest for anencephaly (100%), trisomy 13 (82%), and trisomy 18 (74%), while no first-year deaths were reported for glaucoma, bladder exstrophy, and persistent cloaca. The majority (36 of 54 or 67%) of the birth defects had a mortality rate of less than 25%. Among the 51 structural birth defects, 38 (75%) had higher first-year mortality rate for cases with chromosomal abnormalities and 42 (82%) had higher first-year mortality rates for cases with other major structural birth defects. The mortality rate among 1986-1992 deliveries was higher than the mortality rate among 1993-1999 deliveries for 37 (69%) of the 54 birth defects. This study indicates that first-year mortality rates vary widely by type of birth defect, although the mortality rate for the majority of birth defects is relatively low. The presence of a chromosomal abnormality or other structural birth defect increases the mortality rate, and mortality rates for the majority of birth defects have declined in Hawaii during the study period.

Deletion 15q24-26 in prenatally detected diaphragmatic hernia: increasing evidence of a candidate region for diaphragmatic development

Survival of children with congenital diaphragmatic hernia (CDH) is mainly dependent on the extent of lung hypoplasia and the presence of additional congenital anomalies or chromosomal aberrations. A chromosomal deletion 15q25-q26.2 in a fetus with prenatally diagnosed CDH and growth retardation is reported. Despite optimal pre- and neonatal management the baby died shortly after birth. There is increasing evidence that the long arm of chromosome 15, and especially the region 15q24 to 15q26, plays a crucial role in the development of the diaphragm. The finding of a deletion within 15q24-26 in a fetus with CDH has to be considered a predictor of poor prognosis. It is of utmost interest for proper parental counselling to search in fetuses with CDH for subtle chromosomal lesions paying special attention to chromosome 15q.

Outcome after prenatal diagnosis of hypoplastic left-heart syndrome: a case series

BACKGROUND

Traditionally, after prenatal diagnosis of hypoplastic left-heart syndrome (HLHS) couples have been offered termination of pregnancy or comfort care. Success of postnatal surgical options such as the Norwood procedure have been associated with survival of up to 60%. Whether survival is affected by the congenital anomaly being identified prenatally or postnatally remains uncertain.

METHODS

We reviewed all cases of prenatally diagnosed HLHS referred to the Fetal Medicine Unit at Birmingham Women's Hospital over 6 years between 1994 and 1999.

FINDINGS

87 cases of HLHS were referred at a median gestational age (95% CI) of 23 (19-37) weeks. Of these, 53 (61%) chose prenatal karyotyping. The overall frequency of abnormal karyotype was found in seven of 59 cases (12%) and associated structural anomalies in 18 of 87 (21%). After counselling, 38 of 87 couples (44%) chose termination of pregnancy. Of the remaining 49 fetuses, 11 (23%) were not considered for postnatal surgery because of parental choice and they died after compassionate care. Of the 36 babies who had surgery postnatally, 12 survived (33%). We recorded a survival rate of 38% for the stage-1 Norwood procedure in the prenatally diagnosed HLHS in our centre. These data suggest that at the point of prenatal detection, the overall survival rate for fetuses with HLHS is 25% (if terminated pregnancies are excluded).

INTERPRETATION

Fetal echocardiography allows early diagnosis of HLHS and gives clinicians the opportunity to triage this group dependent on prenatal findings, including karyotyping and the exclusion of other structural anomalies. These prospective data provide up-to-date information on the basis of which parents can make decisions.

Outcome of congenital diaphragmatic hernia

The outcome of congenital diaphragmatic hernia (CDH) differs for different stages of the fetus or infant's life (i.e., antenatal, immediate postnatal, and postoperative). Assessing combined data from nonrandomized studies is technically difficult. Following recognized methods of reviewing such trials, we aimed to review the available literature on the outcome of CDH to provide a guide to clinicians when counselling parents who have a fetus/infant with this condition. Thirty-five studies reporting data for CDH from 1985 to March 1998 were identified using a high sensitive search strategy, hand-searching journals, and reviewing references of relevant studies. These were systematically reviewed. The median overall mortality was 58% (interquartile range (IQR), 43-65%) for babies diagnosed in utero, 48% (IQR, 35-55%) if born alive, and 33% (IQR, 18-54%) postoperatively. Diagnosis before 25 weeks of gestation is not a uniformly bad prognostic indicator (median mortality, 60%). Outcome was worse for those fetuses with other anomalies (median mortality, 93%). The median percentage mortality for all infants born alive and treated in extracorporeal membrane oxygenation (ECMO) centers was 34% (IQR, 26-47%). Median percentage mortality for all ECMO-treated infants was 44% (IQR, 35-50%). Different treatment strategies may have a variable impact on outcome. These figures, together with local data, may help in parental counselling on prognosis for fetuses/infants with CDH.

Congenital diaphragmatic hernia: a meta-analysis of mortality factors

PURPOSE

The aim of this study was to review all available studies reported in the English-language literature from 1975 through 1998, and by meta-analysis assess the importance of prenatal diagnosis, associated malformations, side of hernia, timing of surgery, and study population on mortality rates in patients with congenital diaphragmatic hernia (CDH).

METHODS

One-hundred-two studies were identified, and 51 studies (2,980 patients) fulfilled the prespecified inclusion criteria. Studies were grouped according to study population into: (I) fetuses diagnosed prenatally; (II) neonates admitted to a treatment center; and (III) population-based studies.

RESULTS

Pooled total mortality rate was significantly higher in category I than in category III (75.6% v 58.2%, P < .001). Pooled hidden postnatal mortality rate (deaths before admittance to a treatment center) in population-based studies was 34.9%. Prenatally diagnosed patients in both category II and III had significantly higher mortality rates than those diagnosed postnatally. Mortality rates were significantly higher among CDH infants with associated major malformations compared with isolated CDH in all 3 categories. An increased mortality rate in right-sided CDH was found in category II and III.

CONCLUSIONS

Prenatal diagnosis of CDH, presence of associated major malformations, and the study population have a major influence on mortality rate. The very high mortality rate in studies of fetuses with a prenatal diagnosis of CDH should be taken into account in prenatal counselling.

Partial trisomy 8q and partial monosomy 15q associated with congenital hydrocephalus, diaphragmatic hernia, urinary tract anomalies, congenital heart defect and kyphoscoliosis

We describe perinatal findings in a female fetus with partial trisomy 8q(8q24.1-->8qter) and partial monosomy 15q(15q26.1-->15qter) resulting from a paternal t(8;15) reciprocal translocation. Prenatal sonographic examination showed intra-uterine growth retardation, bilateral ventriculomegaly, cardiomegaly with arrhythmia, anhydramnios, and absent kidney and urinary bladder images. The pregnancy was terminated at 28 weeks of gestation. At birth, the infant manifested typical dysmorphic features of partial trisomy 8q. Necropsy further revealed hydrocephalus, congenital diaphragmatic hernia, ventricular septal defect, a horseshoe kidney with renal hypoplasia, and kyphoscoliosis. Our case shows that the coexistence of partial trisomy 8q24.1-->8qter and partial monosomy 15q26.1-->15qter are more detrimental than either defect alone and can result in a complex of major malformations. Prenatal ultrasound examination and cytogenetic assessment should be offered in subsequent pregnancies.

Prenatal diagnosis of an 8p23.1 deletion in a fetus with a diaphragmatic hernia and review of the literature

The prenatal diagnosis of an 8p23.1 deletion is reported. The diagnosis was ascertained at 22 weeks of gestation because of the discovery of a diaphragmatic hernia at ultrasound. Following cytogenetic studies and counselling, the pregnancy was terminated. An autopsy confirmed the presence of a diaphragmatic hernia and revealed also the existence of an atrio-ventricular canal (AVC) and an atrial septal defect (ASD). The clinical features of this antenatally diagnosed case are compared with those observed in 16 previously reported cases with an identical deletion of the short arm of chromosome 8. This suggests that a deletion 8p23.1 should be considered whenever a diaphragmatic hernia and/or an AVC is detected on ultrasound.