Unexpected intrauterine death following resolution of hydrops fetalis after betamethasone treatment in a fetus with a large cystic adenomatoid malformation of the lung

Rare Lung Diseases: Congenital Malformations

Increasingly, congenital thoracic malformations (CTMs) are diagnosed on antenatal ultrasound, but we lack the evidence to suggest rational management, not least because descriptive terms are used inconsistently. This review describes a simplified clinical classification of CTMs, and contrasts it with pathological descriptions. The age related presentations of CTM are described, together with the differential diagnoses of cystic masses presenting both antenatally and postnatally. Antenatally diagnosed CTMs rarely require intervention before birth; and urgent treatment is only required postnatally if the baby is symptomatic and does not respond to medical management. The asymptomatic baby with an antenatal diagnosis of a CTM presents a management conundrum. Definitive imaging is with high-resolution computed tomography (HRCT), but the optimal timing of imaging is unclear. Whether surgery should be offered to asymptomatic infants is also unclear; in the medium term, 5 % of asymptomatic babies will require surgery for complications of the disease. The most vexed question is malignant change; the risk in the medium term is probably less than 5 %, but we have no way of delineating a high-risk group. Indeed, malignancy has been described even after complete resection of a CTM. The author's personal management is to advocate surgery in the second year of life for all except for the most trivial CTMs, but many would differ and advocate conservative management. More data are needed if we are to rationalise our approach to these infants.

The increasing incidence of foetal echogenic congenital lung malformations: an observational study

OBJECTIVES

The aim of this study was to investigate the incidence of congenital lung malformations over the past 19 years. Congenital lung malformations (CLM) are a heterogeneous group of lung abnormalities. The antenatal diagnosis is important for foetal and neonatal management but there have been no studies examining whether the reported incidence of this abnormality is constant.

METHODS

A retrospective cross-sectional study of cases identified from the Wessex Antenatally Detected Anomalies (WANDA) register 1994-2012.

RESULTS

One hundred and thirty-three cases of CLM in 524 372 live and stillbirths were identified. All but seven were identified on antenatal ultrasound. During the early registry (1994-1998) the average incidence of CLM was 1.27 per 10,000 births. By the last 4 years (2008-2012) this had risen to 4.15 per 10,000 births, with a progressive increase during the intervening years.

CONCLUSION

There was over a three-fold increase in the antenatally detected CLM in the Wessex region 1994-2012. Comparison with the antenatal detection of diaphragmatic hernia suggests that this is a true rise in incidence rather than an artefactual increase due to increased antenatal recognition secondary to improved ultrasound resolution and operator experience. These results have clinical and cost implications for practitioners of foetal medicine, neonatology and paediatric surgery services.

Glucocorticoids and foetal heart maturation; implications for prematurity and foetal programming

Glucocorticoids are steroid hormones, essential in mammals to prepare for life after birth. Blood levels of glucocorticoids (cortisol in most mammals including humans; corticosterone in rats and mice) rise dramatically shortly before birth. This is mimicked clinically in the routine administration of synthetic glucocorticoids to pregnant women threatened by a preterm birth or to preterm infants to improve neonatal survival. Whilst effects on lung are well documented and essential for postnatal survival, those on heart are less well known. In this study, we review recent evidence for a crucial role of glucocorticoids in late gestational heart maturation. Either insufficient or excessive glucocorticoid exposure before birth may alter the normal glucocorticoid-regulated trajectory of heart maturation with potential life-long consequences.

An unusual prenatal manifestation of a huge congenital cystic adenomatoid malformation with favorable perinatal outcome

Congenital cystic adenomatoid malformation (CCAM) is a rare condition which is easily detectable by prenatal ultrasonography. Fetuses with large CCAMs associating with hydrops are predisposed to perinatal mortality, therefore prenatal intervention is required. While macrocystic CCAM is treated prenatally by thoracentesis or thoraco-amniotic shunt, microcystic or mixed CCAM is difficult to manage in the fetus. In these latter lesions, fetal lobectomy, sclerotherapy, or laser ablation was used to treat lesions directly. We present an unusual prenatal case of mixed CCAM associating with hydrops and marked ascites, which was conservatively managed with prenatal abdomino-amniotic shunting and successfully treated by postnatal surgery.

Prenatal interventions for fetal lung lesions

The widespread availability of high resolution ultrasound equipment and almost universal routine anatomy scanning in all pregnant women in the developed world has lead to increased detection of abnormalities in the fetal thorax. Already in the 1980s, large pleural effusions and significant macrocystic lesions in the fetus were easily detected on ultrasound. However, smaller lung tumours were often missed. Nowadays, fetal medicine centres receive many referrals for evaluation of fetal lung lesions, of which the most common are congenital cystic adenomatoid malformation and bronchopulmonary sequestration. Almost invariably, both the parents and the referring physicians experience anxiety after detection of large lung masses in the fetus. However, the vast majority of the currently detected fetal lung lesions have an excellent prognosis without the need for prenatal intervention. In the small group of fetuses in which the prognosis is poor, almost exclusively those with concomitant fetal hydrops and cardiac failure, several options for fetal therapy exist, often with a more than 50% survival rate. Indications, techniques, complications and outcomes of these interventions will be described in this review.

Prenatal presentation and postnatal management of congenital thoracic malformations

The antenatal finding of a congenital thoracic malformation (CTM) leads to anxiety in the parents and uncertainty as to the optimal management. The antenatal spectrum of CTM includes congenital cystic adenomatoid malformation, sequestration, congenital lobar emphysema, enteric and bronchogenic cysts, and bronchial atresia. Most lesions require no antenatal intervention, and shrink substantially in the third trimester, but if fetal hydrops develops, then antenatal intervention is required, occasionally medical but more usually surgical, because mortality is high. If the baby is symptomatic in the newborn period, then some form of surgical intervention is clearly required. The asymptomatic baby presents a therapeutic dilemma. Advocates of early surgery point to the complications of CTM, which include infection, pneumothorax, bleeding and malignant transformation. Those who are proponents of conservative management retort that some CTM disappear postnatally, and that the complication rate is unknown; many children appear never to need surgery. Furthermore, there is clearcut evidence that excision of a CTM does not totally eliminate the risk of a subsequent malignancy. It is clear that, both antenatally and postnatally, counselling of the family on a case by case basis is needed. The limitations of present evidence should be stressed. Different families will make different decisions about postnatal surgery in an asymptomatic baby. If surgery is performed, morbidity is low, particularly with a video-assisted thoracoscopic (VATS) procedure.

Effect of Maternal Betamethasone Administration on Prenatal Congenital Cystic Adenomatoid Malformation Growth and Fetal Survival

OBJECTIVE

To evaluate the effect of prenatal steroid treatment on the growth of congenital cystic adenomatoid malformations (CCAM) and survival in affected fetuses not amenable to other percutaneous ultrasound-guided prenatal interventions.

METHODS

A retrospective review of patients with a CCAM or hybrid lesion treated with two maternal prenatal betamethasone injections was performed. Patients receiving cyst aspiration or thoracoamniotic shunting at the time of or after steroid administration were excluded. Growth rates and survival data were compared to historical non-steroid treated controls.

RESULTS

Eleven patients were treated with prenatal steroids (10 microcystic and 1 macrocystic). Survival was 100% in fetuses with hydrops (5/5) or a CCAM volume ratio (CVR) >1.6 (7/7) at the time of steroid administration. This compares to a mortality of 100 and 56.2% respectively in historical non-treated controls. Resolution of hydrops was seen in 80% (4/5) of steroid-treated patients. CCAM growth rates were variable after steroid administration. However, when compared to historical data where CVR and CCAM volume have been documented to increase until 28 weeks' gestation, the CVR and CCAM volume growth rates decreased in 72.73% and 50% of patients respectively from the time of steroid administration to 28 weeks' gestation.

CONCLUSIONS

In the fetus with a CCAM, the presence of hydrops fetalis or a CVR >1.6 is indicative of poor fetal outcome without prenatal intervention. The observed effect of antenatal steroid treatment on CCAM growth is variable, but its potential to improve survival in these high-risk groups is encouraging and warrants further controlled evaluations.