Effect of single and multiple courses of maternal betamethasone on prenatal congenital lung lesion growth and fetal survival

Integrative analysis of bulk and single-cell RNA sequencing reveals the gene expression profile and the critical signaling pathways of type II CPAM

BACKGROUD

Type II congenital pulmonary airway malformation (CPAM) is a rare pulmonary microcystic developmental malformation. Surgical excision is the primary treatment for CPAM, although maternal steroids and betamethasone have proven effective in reducing microcystic CPAM. Disturbed intercellular communication may contribute to the development of CPAM. This study aims to investigate the expression profile and analyze intercellular communication networks to identify genes potentially associated with type II CPAM pathogenesis and therapeutic targets.

METHODS

RNA sequencing (RNA-seq) was performed on samples extracted from both the cystic area and the adjacent normal tissue post-surgery in CPAM patients. Iterative weighted gene correlation network analysis (iWGCNA) was used to identify genes specifically expressed in type II CPAM. Single-cell RNA-seq (scRNA-seq) was integrated to unveil the heterogeneity in cell populations and analyze the communication and interaction within epithelial cell sub-populations.

RESULTS

A total of 2,618 differentially expressed genes were identified, primarily enriched in cilium-related biological process and inflammatory response process. Key genes such as EDN1, GPR17, FPR2, and CHRM1, involved in the G protein-coupled receptor (GPCR) signaling pathway and playing roles in cell differentiation, apoptosis, calcium homeostasis, and the immune response, were highlighted based on the protein-protein interaction network. Type II CPAM-associated modules, including ciliary function-related genes, were identified using iWGCNA. By integrating scRNA-seq data, AGR3 (related to calcium homeostasis) and SLC11A1 (immune related) were identified as the only two differently expressed genes in epithelial cells of CPAM. Cell communication analysis revealed that alveolar type 1 (AT1) and alveolar type 2 (AT2) cells were the predominant communication cells for outgoing and incoming signals in epithelial cells. The ligands and receptors between epithelial cell subtypes included COLLAGEN genes enriched in PI3K-AKT singaling and involved in epithelial to mesenchymal transition.

CONCLUSIONS

In summary, by integrating bulk RNA-seq data of type II CPAM with scRNA-seq data, the gene expression profile and critical signaling pathways such as GPCR signaling and PI3K-AKT signaling pathways were revealed. Abnormally expressed genes in these pathways may disrupt epithelial-mesenchymal transition and contribute to the development of CPAM. Given the effectiveness of prenatal treatments of microcystic CPAM using maternal steroids and maternal betamethasone administration, targeting the genes and signaling pathways involved in the development of CPAM presents a promising therapeutic strategy.

Prenatally Diagnosed Large Lung Lesions: Timing of Resection and Perinatal Outcomes

INTRODUCTION

Fetuses with large lung lesions including congenital cystic adenomatoid malformations (CCAMs) are at risk for cardiopulmonary compromise. Prenatal maternal betamethasone and cyst drainage for micro- and macrocystic lesions respectively have improved outcomes yet some lesions remain large and require resection before birth (open fetal surgery, OFS), at delivery via an Ex Utero Intrapartum Treatment (EXIT), or immediately post cesarean section (section-to-resection, STR). We sought to compare prenatal characteristics and outcomes in fetuses undergoing OFS, EXIT, or STR to inform decision-making and prenatal counseling.

METHODS

A single institution retrospective review was conducted evaluating patients undergoing OFS, EXIT, or STR for prenatally diagnosed lung lesions from 2000 to 2021. Specimens were reviewed by an anatomic pathologist. Lesions were divided into "CCAMs" (the largest pathology group) and "all lung lesions" since pathologic diagnosis is not possible during prenatal evaluation when care decisions are made. Prenatal variables included initial, greatest, and final CCAM volume-ratio (CVR), betamethasone use/frequency, cyst drainage, and the presence of hydrops. Outcomes included survival, ECMO utilization, NICU length of stay (LOS), postnatal nitric oxide use, and ventilator days.

RESULTS

Sixty-nine percent (59 of 85 patients) of lung lesions undergoing resection were CCAMs. Among patients with pathologic diagnosis of CCAM, the initial, largest, and final CVRs were greatest in OFS followed by EXIT and STR patients. Similarly, the incidence of hydrops was significantly greater and the rate of hydrops resolution was lower in the OFS group. Although the rate of cyst drainage did not differ between groups, maternal betamethasone use varied significantly (OFS 60.0%, EXIT 100.0%, STR 74.3%; p = 0.0378). Notably, all OFS took place prior to 2014. There was no difference in survival, ventilator days, nitric oxide, NICU LOS, or ECMO between groups. In multiple variable logistic modeling, determinants of survival to NICU discharge among patients undergoing resection with a pathologic diagnosis of CCAM included initial CVR <3.5 and need for <3 maternal betamethasone doses.

CONCLUSION

For CCAMs that remain large despite maternal betamethasone or cyst drainage, surgical resection via OFS, EXIT, or STR are viable options with favorable and comparable survival between groups. In the modern era there has been a shift from OFS and EXIT procedures to STR for fetuses with persistently large lung lesions. This shift has been fueled by the increased use of maternal betamethasone and introduction of a Special Delivery Unit during the study period and the appreciation of similar fetal and neonatal outcomes for STR vs. EXIT and OFS with reduced maternal morbidity associated with a STR. Accordingly, efforts to optimize multidisciplinary perinatal care for fetuses with large lung lesions are important to inform patient selection criteria and promote STR as the preferred surgical approach in the modern era.

LEVEL OF EVIDENCE

Level IV.

Morphologic Features in Congenital Pulmonary Airway Malformations and Pulmonary Sequestrations Correlate With Mutation Status: A Mechanistic Approach to Classification

Congenital pulmonary airway malformations (CPAMs) have a range of morphologies with varying cyst sizes and histologic features (types 1 to 3). Evidence suggested they arise secondary to bronchial atresia, however, we recently showed that cases with type 1 and 3 morphology are driven by mosaic KRAS mutations. We hypothesized that 2 distinct mechanisms account for most CPAMs: one subset is secondary to KRAS mosaicism and another is due to bronchial atresia. Cases with type 2 histology, similar to sequestrations, would be related to obstruction and therefore negative for KRAS mutations regardless of cyst size. We sequenced KRAS exon 2 in type 2 CPAMs, cystic intralobar and extralobar sequestrations, and intrapulmonary bronchogenic cysts. All were negative. Most sequestrations had a large airway in the subpleural parenchyma adjacent to the systemic vessel, anatomically confirming bronchial obstruction. We compared morphology to type 1 and 3 CPAMs. On average, type 1 CPAMs had significantly larger cysts, but there remained substantial size overlap between KRAS mutant and wild-type lesions. Features of mucostasis were frequent in sequestrations and type 2 CPAMs, while their cysts were generally simple and round with flat epithelium. Features of cyst architectural and epithelial complexity were more common in type 1 and 3 CPAMs, which rarely showed mucostasis. Similarity in histologic features among cases that are negative for KRAS mutation support the hypothesis that, like sequestrations, the malformation of type 2 CPAMs is related to obstruction during development. A mechanistic approach to classification may improve existing subjective morphologic methods.

Surgical Management of Congenital Lung Malformations

Congenital lung malformations (CLMs) are commonly diagnosed prenatal lesions with varied natural history. Prenatal diagnosis and monitoring help to guide fetal interventions, delivery planning, and need for urgent perinatal surgical interventions. All prenatally diagnosed CLMs should be evaluated postnatally, typically with cross-sectional imaging, because many lesions persist despite the appearance of complete 'regression' in utero. Management of CLMs in asymptomatic infants weighs the surgical and anesthetic risk of prophylactic resection against the risk of expectant management, including the possibility of infection, malignant degeneration, and more complicated surgical resection later with loss of compensatory lung growth.

Management of Congenital Lung Malformations

Congenital lung malformations represent a spectrum of lesions, each with a distinct cause and tailored clinical approach. This article will focus on the following malformations: congenital pulmonary airway malformations, formally known as congenital cystic adenomatoid malformations, bronchopulmonary sequestration, congenital lobar emphysema, and bronchogenic cyst. Each of these malformations will be defined and examined from an embryologic, pathophysiologic, and clinical management perspective unique to that specific lesion. A review of current recommendations in both medical and surgical management of these lesions will be discussed as well as widely accepted treatment algorithms.

The natural history of prenatally diagnosed congenital pulmonary airway malformations and bronchopulmonary sequestrations

BACKGROUND

The natural history of congenital pulmonary airway malformations (CPAM) and bronchopulmonary sequestrations (BPS) is not fully understood, and the management of the newborn with an asymptomatic lesion is a controversial issue. We aimed to study the natural history and outcome of CPAM/BPS at our institution with a policy of watchful waiting, and to investigate if any prognostic factors in the pre- and/or postnatal- period may predict the need for surgery.

MATERIAL AND METHODS

A retrospective review study was conducted of children prenatally diagnosed with CPAM and/or BPS during the 18-year period, from 2002 to 2020. Data from the pre and postnatal period was collected and analysed.

RESULTS

Sixty- six patients with prenatally observed lung lesions were entered in the study, with an overall survival rate of 94%. Fifty-six percent of the lesions decreased in size during gestation. Thirty-one percent had surgery and 69% could be managed conservatively with a median follow-up of 4 years. Nineteen percent developed symptoms after the neonatal period. Children with a presence of mediastinal shift on postnatal imaging (p = 0.003), with a high CVR (p = 0.005) and a large lesion size during gestation (p = 0.014) were significantly more likely to require surgery.

CONCLUSION

Prenatal regression is common among prenatally diagnosed CPAM/BPS and the majority of children that are asymptomatic beyond the neonatal period will remain asymptomatic throughout their childhood. Future analysis with a longer follow-up might give new insights in order to identify children at risk of developing symptoms.

LEVEL OF EVIDENCE

III.

Maternal Steroids in High-Risk Congenital Lung Malformations

INTRODUCTION

The purpose of the present study is to evaluate our institutional management of high-risk congenital lung malformations (CLM) with particular consideration of the use of multiple maternal steroid courses and maternal steroids in CLMs with pathologies other than congenital pulmonary airway malformation (CPAM).

METHODS

A single-center retrospective review was performed for all fetuses evaluated for CLM who received maternal steroids and/or had a CLM volume ratio (CVR) ≥ 1.6 (2015-2020). Fetuses were categorized as receiving no steroids, single steroid, or multiple steroid courses. Outcomes evaluated included CVR growth rate, resolution of early hydrops, and resolution of hydrops. Results are reported with a descriptive analysis.

RESULTS

Nineteen patients were identified who had CVR ≥ 1.6 (single steroid course 9/19, multiple steroid courses 6/19, and no steroids 4/19). A majority (n = 13, 68%) of all lesions had a reduction or no change in CVR between initial and final measurements (single steroid course 7/9, 78%; multiple steroid courses 4/6, 67%). When evaluating by pathology, ≥ 50% of each classification had reduction or no growth of CVR (CPAM 7/11, bronchial atresia 2/4, sequestration 3/3, congenital lobar emphysema 1/1). Seventy five percent (3/4) of lesions with early hydrops had resolution following steroid treatment (single steroid course 1, multiple steroid courses 2). Of the four lesions that had hydrops, only one had resolution after receiving multiple steroid courses.

CONCLUSIONS

Our institutional experience reports the majority of CLM (including pathologies other than CPAM) who received steroids had reduction or no change in CVR. Given the low risk-benefit ratio of maternal steroids, physicians could consider use of multiple steroid courses for CLM refractory to a single course.

Delivery planning for congenital lung malformations: A CVR based perinatal care algorithm

PURPOSE

Congenital lung malformation (CLM) volume ratio (CVR) of ≥1.1 has been shown to be highly predictive of the need for urgent, perinatal surgical intervention. The purpose of this study was to utilize this information to propose a delivery planning and clinical management algorithm based on this threshold.

METHODS

A retrospective cohort study was performed for all fetuses evaluated at our fetal center between 5/2015 and 11/2020. Demographics, ultrasound findings, late gestation CVR (≥27 weeks gestational age), prenatal and postnatal treatment, and outcomes were analyzed with nonparametric univariate analysis based on late gestation CVR of 1.1. Receiver operating characteristic curve analysis was performed to evaluate association between late gestation CVR, hydrops, need for fetal intervention, and need for urgent perinatal surgery.

RESULTS

Of the 90 CLMs referred to our fetal center, 65 had late gestation CVR with a majority <1.1 (47/65, 72%). All patients with late gestation CVR ≥ 1.1 were managed with resection (18/18) with most resections requiring fetal intervention or urgent neonatal resection (13/18). Late gestation CVR < 1.1 were managed with elective resection (36/47, 77%) or non-operative observation (11/47, 23%). Late gestation CVR ≥ 1.1 had 100% sensitivity and NPV for hydrops, need for fetal intervention, and need for urgent perinatal surgery.

CONCLUSION

CLM with CVR ≥ 1.1 were associated with urgent perinatal surgical intervention and expectant mothers should plan for delivery at centers equipped to manage neonatal resuscitation and potential urgent neonatal resection. Conversely, CLM with CVR < 1.1 may be safe to deliver at patient hospital of choice.

Use of Corticosteroids in Prenatal Treatment of Congenital Pulmonary Adenomatoid Malformation: Integrative Review

OBJECTIVE

 To review data on the use of corticosteroids for the treatment of fetuses with high-risk congenital pulmonary adenomatoid malformation (CPAM).

METHODS

 Integrative review based on the literature available on MEDLINE and LILACS, including articles published until November, 2020.

RESULTS

 The initial search resulted in 87 articles, 4 of which were selected for analysis, with all of them being retrospective descriptive observational studies. In the group of fetuses that received only a single corticosteroid cycle, the hydrops resolution rate was 70%, and the survival rate was 83.8%. In fetuses treated with 2 or more cycles of corticosteroids, there was an improvement in the condition of hydrops or edema in a single body compartment in 47%, and survival of 81.8% of the fetuses.

CONCLUSION

 The use of corticosteroids for the prenatal treatment of high-risk CPAM appears to be associated with an improvement in perinatal outcomes.

Intrathoracic shunt displacement with massive pleural effusion after successful shunt placement in a hydropic fetus with multilocular macrocystic congenital pulmonary airway malformation

We successfully performed shunting for a fetus with a multilocular macrocystic lung mass with hydrops at 22 weeks' gestation. Complete resolution of hydrops was achieved; however, at 35 weeks' gestation, the fetus developed acute massive pleural effusion. Fetal ultrasound examination revealed that one end of the shunting tube had migrated downward in the thoracic cavity, which led to fluid draining from the lung cyst. The baby was delivered at term and was discharged following neonatal intensive care management. Intrathoracic displacement of the shunt can occur, followed by massive pleural effusion due to drainage of cystic fluid.

ATS Core Curriculum 2020. Pediatric Pulmonary Medicine

The American Thoracic Society Core Curriculum updates clinicians annually in adult and pediatric pulmonary disease, medical critical care, and sleep medicine, in a 3- to 4-year recurring cycle of topics. These topics will be presented at the 2020 International Conference. Below is the pediatric pulmonary medicine core, including pediatric hypoxemic respiratory failure; modalities in noninvasive management of chronic respiratory failure in childhood; surgical and nonsurgical management of congenital lung malformations; an update on smoke inhalation lung injury; an update on vaporizers, e-cigarettes, and other electronic delivery systems; pulmonary complications of sarcoidosis; pulmonary complications of congenital heart disease; and updates on the management of congenital diaphragmatic hernia.

Fetal ultrasound and magnetic resonance imaging: a primer on how to interpret prenatal lung lesions

Fetal lung lesions include common lesions such as congenital pulmonary airway malformation (CPAM), bronchopulmonary sequestration (BPS) and combined CPAM-BPS hybrid lesions, as well as less common entities including congenital lobar emphysema/obstruction, bronchial atresia, bronchogenic cysts and rare malignant pulmonary lesions such as pleuropulmonary blastoma. Fetal lung lesions occur in approximately 1 in 15,000 live births and are thought to arise from a spectrum of abnormalities related to airway obstruction and malformation, with the lesion type depending on the timing of insult, level of bronchial tree involvement, and severity of obstruction. Lesions vary from small and asymptomatic to large and symptomatic with significant mass effect on surrounding structures. Accurate diagnosis and characterization of these anomalies is crucial for guiding patient counseling as well as perinatal and postnatal management. The goal of this review is to provide an overview of normal fetal lung appearance and imaging features of common and uncommon lesions on both ultrasound and MR imaging, and to discuss key aspects in reporting and evaluating the severity of these lesions.

Current perspective and scope of fetal therapy: part 2

Fetal therapy has been defined as any therapeutic intervention either invasive or noninvasive for correcting or treating any fetal malformation or condition. Invasive fetal therapy have its own set of maternal and fetal complications and invasive approach is not feasible in many of fetal conditions that are candidate for fetal therapy. Many such fetal conditions have been treated successfully by medical or noninvasive management. In medical fetal therapy, mothers are treated with medications which are transferred to fetus through placenta and exert positive effect on the fetus, thus avoiding complications that are seen secondary to invasive fetal therapy. The fetal conditions that have been managed with medical therapy includes fetal and neonatal alloimmune thrombocytopenia, neural tube defect, congenital adrenal hyperplasia, perinatal infections, respiratory distress syndrome, inborn error of metabolism, and congenital cystic adenomatoid malformation. This review will cover the medical or noninvasive aspect of fetal therapy and will highlight the progress made in the management of these fetal conditions.

Fetal lung interstitial tumor: Prenatal presentation of a rare fetal malignancy

Fetal lung interstitial tumor (FLIT) is a rare fetal malignancy that is typically diagnosed in the postnatal period, or, if recognized prenatally can mimic a benign lesion such as congenital pulmonary airway malformation. We present the earliest case of a FLIT tumor described by ultrasound and MRI at 26 weeks of gestation. Our case highlights features suggestive of FLIT including presentation later in gestation in combination with findings on fetal MRI such as a solid appearance with radiating curved bands of high signal within and along the periphery of the lesion (not as intensely high signal as the typical CPAM), possibly detailing a radiographic signature for these tumors. The role of betamethasone for these tumors is not known.

Prenatal Imaging to Predict Need for Urgent Perinatal Surgery in Congenital Lung Lesions

BACKGROUND

Congenital lung malformations (CLMs) have a variable natural history: some patients require urgent perinatal surgical intervention (UPSI) and others remain asymptomatic. These lesions have potential growth until 26-28 wk gestation. CLM volume ratio (CVR) has been shown to predict the risk of hydrops in CLMs. However, no criteria exist to delineate lesions requiring urgent surgical intervention in the perinatal period. Our goal was to determine prenatal diagnostic features that predict the need for UPSI in patients diagnosed with CLM.

METHODS

Records and imaging features of all fetuses evaluated by our fetal center between May 2015 and December 2018 were retrospectively reviewed. Data included demographics, fetal ultrasound and magnetic resonance imaging, CVR, surgical treatment, and outcome. Features were analyzed for their ability to predict the need for UPSI.

RESULTS

Sixty-four patients were referred for CLM, with 48 patients serially followed. Nine (18.8%) patients were followed nonoperatively, 35 (72.9%) underwent resection, and four (8.3%) were lost to follow-up. Of the patients who underwent resection, 24 (68.5%) were electively resected and 11 were urgently resected. Five (14.3%) patients underwent ex utero intrapartum treatment resection, and six (17.1%) were urgently resected for symptomatic CLM. There were no cases of UPSI with final CVR <1.1. Of the patients with final CVR 1.1-1.7, 43% required urgent resection. CVR ≥1.1 has 100% sensitivity and 87.8% specificity to predict patients requiring UPSI (area under the curve of 0.98).

CONCLUSIONS

A final CVR ≥1.1 is highly predictive for UPSI. Patients with a final CVR ≥1.1 should be referred for delivery at centers with pediatric surgeons equipped for potential UPSI for CLM.

Further delineation of the phenotypic spectrum of nevus comedonicus syndrome to include congenital pulmonary airway malformation of the lung and aneurysm

Nevus comedonicus syndrome (NCS) is a rare epidermal nevus syndrome characterized by ocular, skeletal, and central nervous system anomalies. We present a 23-month-old boy with a history of a congenital pulmonary airway malformation (CPAM) of the lung and a congenital cataract who developed progressive linear and curvilinear plaques of dilated follicular openings with keratin plugs (comedones) on parts of his scalp, face, and body consistent with nevus comedonicus. MRI of the brain demonstrated an aneurysm of the right internal carotid artery. Genetic testing identified NEK9 c.1755_1757del (p.Thr586del) at mean allele frequency of 28% in the nevus comedonicus. This same mutation was present in the CPAM tissue. This is the first case of a CPAM in a patient with an epidermal nevus syndrome. This case expands the phenotype of nevus comedonicus syndrome to include CPAM and vascular anomalies.

Dynamic discriminant model for predicting respiratory distress at birth based on mass volume ratio in fetuses with congenital lung malformation

OBJECTIVES

The congenital lung malformation volume ratio (CVR) is a prenatal ultrasound measurement that parameterizes congenital lung malformation (CLM) size. The aims of this study were to use serial measurements to create estimated growth curves of fetal CVR for asymptomatic and symptomatic neonates with CLM and to investigate whether a discriminant prognostic model based on these measurements could predict accurately which fetuses with CLM will require invasive respiratory support at delivery and should therefore be delivered at a tertiary-care facility.

METHODS

This was a retrospective study of fetuses diagnosed prenatally with CLM at three tertiary-care children's hospitals between 2009 and 2016. Those with two or more sonographic measurements of CVR were included. Serial fetal CVR measurements were used to create estimated growth curves for neonates with and those without respiratory symptoms at delivery, defined as requiring invasive respiratory support for the first 24 h after delivery. A discriminant model based on serial CVR measurements was used to calculate the dynamic probability of the need for invasive respiratory support. The performance of this model overall and in preterm and term neonates was compared with those using maximum CVR thresholds of 1.0 and 1.6.

RESULTS

Of the 147 neonates meeting the inclusion criteria, 16 (10.9%) required postnatal invasive respiratory support. The estimated CVR growth curve models showed different growth trajectories for asymptomatic and symptomatic neonates, with significantly higher CVR in symptomatic neonates, and values peaking late in the second trimester at around 25 weeks' gestation in asymptomatic neonates. All prognostic methods had high accuracy for the prediction of the need for invasive respiratory support in term neonates, but the discriminant model had the best performance overall (area under the receiver-operating characteristics curve (AUC) = 0.88) and in the preterm population (AUC = 0.85).

CONCLUSIONS

The estimated CVR growth curves showed different growth patterns in asymptomatic and symptomatic neonates with CLM. The dynamic discriminant model performed well overall and particularly in neonates that were carried to term. Development of an externally validated clinical tool based on this analysis could be useful in determining the site of delivery for fetuses with CLM. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Congenital Cystic Lung Lesions: Redefining the Natural Distribution of Subtypes and Assessing the Risk of Malignancy

Asymptomatic cystic lung lesions-congenital pulmonary airway malformations (CPAMs), sequestrations, and bronchogenic cysts-are commonly diagnosed prenatally. Indications to resect are to eliminate risk of malignancy or infection. CPAMs consist of a spectrum of malformations, with type 1 historically considered the most common. Mucinous cell clusters, seen almost exclusively in type 1, are premalignant lesions at risk for progression to mucinous adenocarcinoma. We reviewed and classified 2.5 years of consecutive, prenatally diagnosed lesions as extralobar sequestration, intralobar sequestration, type 1 CPAM, type 2 CPAM/bronchial atresia, or "other" to determine the distribution of lesion types and risk of malignancy. One hundred eighty-four lesions in 174 patients showed type 1 CPAM to be least common subtype. Type 1 CPAMs had more severe presentation, infrequently had features of obstruction, and usually had cysts ≥2 cm. Fifteen of eighteen type 1 CPAMs had mucinous cell clusters (total risk, 8%), with mucous cells outside main cyst in 12/15. No pleuropulmonary blastomas were identified. Additional historic cases were reviewed to further evaluate risk of malignancy. Over 14 years, 28 infants with fetal/type 1 lesions were identified, with clusters of mucinous cells in 75% of cases. A total of 9 pleuropulmonary blastomas were diagnosed in 6 patients over 16 years. Contrary to historical studies, type 1 CPAMs are much less common than type 2, likely related to detection of asymptomatic lesions prenatally. A majority of type 1 CPAMs contain mucinous cell clusters. This data is useful in management of patients in centers that do not resect asymptomatic lesions.

The Utility of the Congenital Pulmonary Airway Malformation-Volume Ratio in the Assessment of Fetal Echogenic Lung Lesions: A Systematic Review

Although relatively uncommon, the incidence of fetal echogenic lung lesions - a heterogeneous group of anomalies that includes congenital pulmonary airway malformations (CPAM) and bronchopulmonary sequestrations (BPS) - has increased recently. Two decades ago, the CPAM-volume ratio (CVR) was first described as a tool to predict the development of hydrops, with this outcome found to be unlikely in fetuses with CVRs of ≤1.6 cm2. Since then, no clear international consensus has evolved as to the optimal CVR thresholds for the prediction of fetal/neonatal outcomes. This systematic review aimed to assess all original research studies that reported on the predictive utility of the CVR. Potentially relevant papers were identified through searching for citations of the paper that originally described the CVR, in addition to keyword searches of electronic databases. Fifty-two original research papers were included in the final review. Of these, 34 used the CVR for descriptive purposes only, 5 assessed the validity of established thresholds in different populations, and 13 proposed new thresholds. The evidence identified in this review would suggest that a threshold much lower than 1.6 cm2 is likely to be of greater utility in most populations for many outcomes of perinatal relevance. For neonatal outcomes (mostly respiratory compromise at birth), a CVR on the initial ultrasound scan ranging from 0.5 to 1.0 cm2 appears to have the greatest predictive value. Although a number of studies concurred that 1.6 cm2 was a useful threshold for the prediction of hydrops, many others were unable to assess this due to the rarity of this complication. For this reason, thresholds as low as 0.4 cm2 may be more useful for the prediction of a broader range of fetal concerns, including mediastinal shift and fluid collections. Further large-scale studies are required to determine the true utility of this well-established index.

Short-term respiratory outcomes of neonates with symptomatic congenital lung malformations

INTRODUCTION

The purpose of this study was to evaluate short-term respiratory outcomes in neonates with symptomatic congenital lung malformations (CLM).

METHODS

Consecutive newborns who underwent surgical resection of a CLM were retrospectively reviewed. Demographic, prenatal, and outcomes data were analyzed as appropriate (p < 0.05).

RESULTS

Twenty-one neonates were managed at a median gestational age of 36.2 weeks [interquartile range (IQR), 33.8-39.0]. Endotracheal intubation was required in 14 (66.7%) for a median of 7.5 days [interquartile range (IQR), 3.0-25.8]. Three (14.3%) children underwent ex utero intrapartum treatment-to-resection, and another 14 (66.7%) had neonatal lung resections performed at a median age of 2.0 days (IQR, 0.08-19.5 days). Excluding one patient who received comfort care at birth, all neonates survived to hospital discharge with a median length of hospitalization of 36.5 days (IQR, 23.8-56.5). More than one-quarter were discharged on supplemental oxygen by nasal cannula. Based on a median follow up of 35.5 months (IQR, 19.0-80.8), CLM-related morbidity was still evident in 55.0%.

CONCLUSION

Our study suggests a high incidence of complications and chronic respiratory morbidity after neonatal lung resection for symptomatic CLMs. These data highlight the need to provide realistic expectations in perinatal counseling discussions with families and the importance of coordinating appropriate multidisciplinary follow up for these children.

LEVEL OF EVIDENCE

Level IV.

Fetal Sclerotherapy for Hydropic Congenital Cystic Adenomatoid Malformations of the Lung Refractory to Steroids: A Case Report and Review of the Literature

Microcystic congenital cystic adenomatoid malformations (CCAM), when associated with hydrops, carry a dismal prognosis. Options for treatment are limited and experimental, including antenatal corticosteroids, open fetal surgery, laser ablation and, more recently, sclerotherapy. We describe a case of a large, predominantly microcystic CCAM in a hydropic fetus treated successfully with direct interstitial injection of a sclerosant agent (3% sodium tetradecyl sulfate) at 23+3 weeks gestation, after multiple failed courses of steroids. Elective thoracoscopic right lower lobectomy was performed at 1 year of life and there have been no respiratory or other medical morbidities since. A literature review of fetal lung masses treated with sclerosants antenatally reveals that sclerotherapy may represent a novel treatment option for large hydropic microcystic CCAMs, which are unresponsive to corticosteroids. Further studies are required to evaluate the utility and safety of fetal sclerotherapy, as this may represent an alternative minimally invasive treatment option to fetal lobectomy.

Congenital Lobar Overinflation: A Rare Enigmatic Lung Lesion on Prenatal Ultrasound and Magnetic Resonance Imaging

OBJECTIVES

To report the ultrasound (US) features in prenatal cases of suspected congenital pulmonary airway malformation or unspecified lung lesions with a final surgical pathologic diagnosis of congenital lobar overinflation (CLO).

METHODS

Institutional Review Board-approved radiology and clinical database searches from 2001 to 2017 were performed for prenatally diagnosed lung lesions with a final diagnosis of CLO. All patients had detailed US examinations in addition to magnetic resonance imaging (MRI). Size, echotexture, and vascularity were assessed with US, and the signal and vascularity were assessed with MRI. Follow-up prenatal US scans, postnatal imaging, and postnatal outcomes were reviewed.

RESULTS

The study population consisted of 12 patients. The median gestational age was 23.3 weeks. The median congenital pulmonary airway malformation volume-to-head circumference ratio was 0.66. Lesion locations were 6 in the lower lobes (4 right and 2 left), 5 in the upper lobes (3 left and 2 right), and 1 in the right middle lobe. The texture was homogeneously echogenic relative to the normal lung in 100% with no visualized macrocysts. Hypervascularity by color Doppler US was observed in 5 cases (41.7%). A T2 hyperintense lung lesion was identified by MRI in 12 of 12 cases (100%), with elongated vessels identified in 11 of 12 cases (91.7%). All 12 cases had pathologically proven CLO.

CONCLUSIONS

Congenital lobar overinflation should be considered in cases of prenatal echogenic lung lesions without macrocysts or classic findings of bronchial atresia. Hypervascularity may be an important imaging feature of a subset of CLO. Most cases become less conspicuous, decrease in size without overt hydrops, and are asymptomatic postnatally.

Clinical cardiac assessment in newborns with prenatally diagnosed intrathoracic masses

Background

Congenital space-occupying thoracic malformations and diaphragmatic hernia have in common pulmonary hypoplasia. Our study aims to assess cardiac involvement during post-natal adaptation.

Methods

A retrospective study was carried out on newborns with prenatally diagnosed intrathoracic mass. Gathering for respiratory distress syndrome (RDS), 35 neonates were compared for clinical course, cardiovascular enzymes, ECG, and ultrasound.

Results

The analysis revealed a high left heart defect rate in patients with severe RDS, without being influenced by the laterality. Ultrasound or laboratory assessment did not detect altered cardiac dimension or cardiomyopathy. Solely ECG signs of right ventricular strain were found. Increased QT-dispersion, T-wave and cardiac variability alterations in the first hours were all expression of non-specific cardiac repolarization disorders but predict worse outcome.

Conclusions

Although RDS is the predominant symptom, slight cardiac dysfunctions should be recognized for prompt treatment. Conventional examinations for postnatal adaption should be integrated by complementary investigations.

Bronchopulmonary Sequestration with Fetal Hydrops in a Monochorionic Twin Successfully Treated with Multiple Courses of Betamethasone

Aim  We present a case of severe bronchopulmonary sequestration (BPS) and fetal hydrops in one of the monochorionic twin successfully treated with multiple courses of betamethasone. Case Report  A 21-year-old gravida 2 para 1 was referred to our hospital for suspected twin-to-twin transfusion syndrome (TTTS) at 28 ^0/7 weeks of gestational age. However, prenatal ultrasound of the larger twin revealed a chest lesion that was associated with significant ascites, massive hydrothorax, scant hepatomegaly, subcutaneous edema, and severe polyhydramnios. Magnetic resonance imaging confirmed the diagnosis of BPS and fetal hydrops. The estimated fetal weight discrepancy between the fetuses was 39% but the criteria for TTTS were not met. Repeated courses of betamethasone (3 courses, each with 2 × 14 mg of betamethasone intramuscularly/week) were administered with subsequent recovery from hydrops and reduction in BPS parameters. Amniodrainage was performed twice to reduce the amniotic fluid amount in affected twin. Postnatally, surgery of BPS was not required and follow-up at 6 months of corrected age revealed no side effects of antenatal steroids in either twin. Conclusion  Antenatal steroids might be considered for noninvasive therapy in high-risk fetal patients with BPS especially when fetal intervention is unsuitable or not available.

The Use of Fetal Bronchoscopy in the Diagnosis and Management of a Suspected Obstructive Lung Mass

Etiologies of fetal lung anomalies include congenital pulmonary airway malformation (CPAM), intra- or extralobar pulmonary sequestration, congenital high airway obstruction syndrome (CHAOS), bronchogenic cyst, and bronchial atresia. Fetal tracheobronchoscopy has been reported both as a diagnostic and therapeutic procedure in the setting of severe congenital lung lesions. In this case report, prenatal imaging of a fetus with a large chest mass was suspicious for an obstructive bronchial lesion. The absence of visible normal lung tissue on the right side and mass effect on the left side raised the concern for pulmonary hypoplasia. After antenatal betamethasone and a period observation, hydropic changes developed. Fetal tracheobronchoscopy was then performed in an effort to identify and decompress the suspected obstructive bronchial lesion. Other than release of bronchial debris, no anatomical abnormalities were visualized. However, the right lung lesion and mediastinal shift both decreased after the fetal bronchoscopy. The newborn underwent postnatal resection of a CPAM Type II and is doing well. We hypothesize that fetal tracheobronchoscopy provided the following potential diagnostic and therapeutic benefits: (1) exclusion of an obstructive bronchial lesion; (2) disimpaction of bronchial debris from the saline lavage that we posit may have contributed to the rapid reduction in CPAM size.

Perinatal Care of Infants with Congenital Birth Defects

Prenatal diagnosis has changed perinatal medicine dramatically, allowing for additional fetal monitoring, referral and counseling, delivery planning, the option of fetal intervention, and targeted postnatal management. Teams participating in the delivery room care of infants with known anomalies should be knowledgeable about specific needs and expectations but also ready for unexpected complications. A small number of neonates will need rapid access to postnatal interventions, such as surgery, but most can be stabilized with appropriate neonatal care. These targeted perinatal interventions have been shown to improve outcome in selected diagnoses.

Short-Term Neurodevelopmental Outcome in Children Born With High-Risk Congenital Lung Lesions

BACKGROUND

This study sought to evaluate neurodevelopmental outcome in survivors of high-risk congenital lung lesions (CLLs) who underwent prenatal intervention or postnatal surgery within the first month of life.

METHODS

Forty-five high-risk CLL survivors underwent assessment using the Bayley Scales of Infant Development, 3rd Edition between July 2004 and December 2016. Scores were grouped as average, at-risk, and delayed based on SD intervals. Correlations between outcome and risk factors were analyzed by Fisher's exact test or two-sided t test as appropriate, with significant p values <0.05.

RESULTS

Open prenatal intervention was required in 13 (28.9%) children (fetal surgical resection, n = 4 , ex utero intrapartum treatment, n = 9), whereas 32 (71.1%) children had respiratory distress postnatally and required resection within the first month of life. Mean age at follow-up was 19.3 ± 10.3 months. Mean composite scores were within the expected average range. A total of 62.2% scored within the average range for all domains. At-risk scores were found in 26.7% of children in at least one domain, and 11.1% had delays in at least one domain. Neurodevelopmental outcome was similar between treatment groups. Prolonged ventilator support and neonatal intensive care unit stay, need for supplemental oxygen at day of life 30, gastroesophageal reflux disease, and delayed enteral feeding were associated with neurologic delays (all p < 0.05).

CONCLUSIONS

Neurodevelopmental scores for high-risk CLL survivors in infancy and toddlerhood are age appropriate. Neither fetal intervention nor the need for postnatal resection within the first month of life increases the risk of delays. Surrogate markers of a complicated neonatal course are predictive of adverse outcome.

Prenatal growth characteristics and pre/postnatal management of bronchopulmonary sequestrations

PURPOSE

The prenatal natural history of intralobar and extralobar bronchopulmonary sequestrations (BPSs), including lesion growth patterns and need for prenatal intervention, have not been fully characterized. We review our series of BPSs to determine their natural history and outcomes in the context of the need for prenatal intervention.

METHODS

A retrospective review of the pre/postnatal course of 103 fetuses with an intralobar (n=44) or extralobar BPS (n=59) managed at a single institution between 2008 and 2015 was performed. Outcomes included prenatal lesion growth trajectory, presence of hydrops, need for prenatal intervention, survival, and postnatal surgical management.

RESULTS

Most extralobar (71%) and intralobar BPSs (94%) decreased in size or became isoechoic from initial to final evaluation. Peak lesion size occurred at 26-28weeks gestation. Eight fetuses developed hydrothorax, four of which (all extralobar BPSs) also developed hydrops. All four hydropic fetuses received maternal betamethasone, and three hydropic fetuses underwent thoracentesis and/or thoracoamniotic shunt placement with subsequent hydrops resolution. All fetuses survived. Forty-one intralobar (93%) and 35 extralobar BPSs (59%) were resected after birth.

CONCLUSIONS

BPSs tend to decrease in size after 26-28weeks gestation and rarely require fetal intervention. Lesions resulting in hydrothorax ± hydrops can be effectively managed with maternal steroids and/or drainage of the hydrothorax.

LEVEL OF EVIDENCE

IV.

Congenital pulmonary airway malformations: state-of-the-art review for pediatrician's use

Congenital pulmonary airway malformations or CPAM are rare developmental lung malformations, leading to cystic and/or adenomatous pulmonary areas. Nowadays, CPAM are diagnosed prenatally, improving the prenatal and immediate postnatal care and ultimately the knowledge on CPAM pathophysiology. CPAM natural evolution can lead to infections or malignancies, whose exact prevalence is still difficult to assess. The aim of this "state-of-the-art" review is to cover the recently published literature on CPAM management whether the pulmonary lesion was detected during pregnancy or after birth, the current indications of surgery or surveillance and finally its potential evolution to pleuro-pulmonary blastoma.

CONCLUSION

Surgery remains the cornerstone treatment of symptomatic lesions but the postnatal management of asymptomatic CPAM remains controversial. There are pros and cons of surgical resection, as increasing rate of infections over time renders the surgery more difficult after months or years of evolution, as well as risk of malignancy, though exact incidence is still unknown. What is known: • Congenital pulmonary airway malformations (CPAM) are rare developmental lung malformations mainly antenatally diagnosed. • While the neonatal management of symptomatic CPAM is clear and includes prompt surgery, controversies remain for asymptomatic CPAM due to risk of infections and malignancies. What is new: • Increased rate of infection over time renders the surgery more difficult after months or years of evolution and pushes for recommendation of early elective surgery. • New molecular or pathological pathways may help in the distinction of type 4 CPAM from type I pleuropulmonary blastoma.

Minimally Invasive Fetal Surgery

Fetal surgery corrects severe congenital anomalies in utero to prevent their severe consequences on fetal development. The significant risk of open fetal operations to the pregnant mother has driven innovation toward minimally invasive procedures that decrease the risks inherent to hysterotomy. In this article, we discuss the basic principles of minimally invasive fetal surgery, the general history of its development, specific conditions and procedures used to treat them, and the future of the field.

Fetal surgery: a critical review

Therapeutic fetal surgical procedures are predicated upon the ability to make an accurate fetal diagnosis. The earliest open fetal surgical procedures were introduced in the 1960s to treat Rh isoimmunisation. They were introduced when it became possible to predict impending fetal demise. Open procedures were abandoned when percutaneous approaches proved superior. The introduction of fetal ultrasound allowed the diagnosis of other congenital anomalies, some being amenable to fetal interventions. Open fetal surgical procedures were initially utilised, with significant maternal morbidity. For some anomalies, percutaneous approaches became favoured. In general, all of these procedures involved significant risks to the mother, to save a baby that was likely to die before or shortly after birth without fetal intervention. Fetal repair for myelomeningocele was a "sea change" in approach. The same maternal risks were taken to improve the quality of life of the affected fetus, not save its life. The completion of the "MOMs Trial" has occasioned a "tsunami" of centres in North America applying this approach. Others are attempting percutaneous repairs, with mixed results. This paper reviews the history of fetal surgery, focusing on the themes of the tension between accurate diagnosis and prognosis and open versus "minimally invasive" approaches.

Bronchopulmonary Sequestration with Morbid Neonatal Pleural Effusion despite Successful Antenatal Treatment

INTRODUCTION

Bronchopulmonary sequestration (BPS) may cause prenatal pleural effusion (PE) or even hydrops. This case describes a fetus presenting with severe PE, which prenatally waned completely under steroid treatment, yet surprisingly reappeared rapidly after birth, requiring early surgical intervention.

CASE DESCRIPTION

A male fetus was diagnosed with left BPS and severe PE. After three courses of prenatal steroid therapy for each recurrence of PE from 27 weeks of gestation, we observed a complete regression of PE prenatally. Yet, PE recurred 18 h after birth and persisted after repeated drainages and steroid therapy. Early total resection of the extralobar BPS was performed and led to complete recovery without recurrence of PE.

CONCLUSION

This report underlines that in cases of BPS presenting with prenatal PE needing fetal intervention, even if full regression of PE is observed before birth, there might be a need for surgical excision during the neonatal period.