Respiratory outcomes in the first 10 years of life in children with gastroschisis: A retrospective cohort study

BACKGROUND

Little attention has been given to the long-term respiratory outcomes of children with gastroschisis. The purpose of this study was to determine if gastroschisis survivors have more respiratory illnesses in their first 10 years of life compared with age-matched controls.

METHODS

We performed a retrospective cohort study of all gastroschisis children born in Manitoba between 1991 and 2017. Gastroschisis cases were identified from a clinical database, and a date of birth-matched control cohort was constructed from a population-based data repository. International Classification of Disease codes were used to compare the risk and frequency of respiratory diagnoses for children with gastroschisis to date of birth-matched controls from 0-5 years of age and 5-10 years of age.

RESULTS

The 0-5 years of age analysis included 117 gastroschisis cases and 1205 date of birth-matched controls; children with gastroschisis had a higher risk of asthma (relative risk [RR] = 1.46; 95% confidence interval [CI]: 1.03, 2.55; p = .029), acute bronchitis/bronchiolitis (RR = 1.61; 95% CI: 1.27, 2.03; p < .001), pneumonia (RR = 1.99; 95% CI: 1.45, 2.72; p < .001), viral pneumonia (RR = 5.15; 95% CI: 1.79, 14.81; p = .007), and pneumonia due to unspecified organism (RR = 2.06; 95% CI: 1.45, 2.92; p < .001). Gastroschisis children 0-5 years of age were also diagnosed more frequently with bronchitis/bronchiolitis (RR = 2.14; 95% CI: 1.79, 2.57; p < .001) and viral pneumonia (RR = 8.10; 95% CI: 3.79, 17.31; p < .001). The 5-10 years of age analysis included 73 cases and 738 controls; no difference in the risk of respiratory illness was found for gastroschisis cases and controls in this age group. However, gastroschisis cases were more frequently diagnosed with bacterial pneumonia (RR = 3.03; 95% CI: 1.67, 5.51; p < .001) and influenza (RR = 3.03; 95% CI: 1.67, 5.51; p < .001).

CONCLUSION

Our study shows that children with gastroschisis have an increased risk of asthma and respiratory infections compared with children without gastroschisis, most noticeably in the first 5 years of life.

The prevalence of hearing loss in children with congenital diaphragmatic hernia: A longitudinal population-based study

BACKGROUND

The true prevalence of hearing loss among children with congenital diaphragmatic hernia (CDH) is unknown, with some studies reporting rates up to 60%.

PURPOSE

The purpose of this study was to determine the prevalence of hearing loss among children with CDH and compare it to age-matched controls.

METHODS

We used population-based datasets to compare the number of hearing loss diagnoses in children younger than 10 years-of-age born between 1992 and 2009 with CDH to date-of-birth matched controls without CDH. Factors associated with CDH disease severity were analyzed to determine their effect on the prevalence of hearing loss. A sensitivity analysis was performed to determine if selection bias of improved care over the course of the study affected hearing loss in CDH patients. The prevalences of hearing loss were compared using Fisher's exact tests and statistical significance was defined as p < 0.05.

RESULTS

A total of 529 children, 38 CDH cases and their 491 date-of-birth matched controls, met the inclusion criteria. Hearing loss was found in 7 children with CDH (18.4%) compared to 26 (5.3%) controls; the risk ratio (RR) of hearing loss was 3.48 (95%CI = 1.61-7.49, p = 0.006). There was no association between CDH disease severity and hearing loss.

CONCLUSIONS

CDH is associated with hearing loss compared to the general population. Our results suggest that congenital factors may contribute to hearing loss in CDH more than perinatal exposures.

LEVEL OF EVIDENCE

3.

The RNA-binding protein Quaking regulates multiciliated and basal cell abundance in the developing lung

RNA-binding proteins (RBPs) form complexes with RNA, changing how the RNA is processed and thereby regulating gene expression. RBPs are important sources of gene regulation during organogenesis, including the development of lungs. The RBP called Quaking (QK) is critical for embryogenesis, yet it has not been studied in the developing lung. Here, we show that QK is widely expressed during rat lung development and into adulthood. The QK isoforms QK5 and QK7 colocalize to the nuclei of nearly all lung cells. QK6 is present in the nuclei and cytoplasm of mesenchymal cells and is only present in the epithelium during branching morphogenesis. QK knockdown in embryonic lung explants caused a greater number of multiciliated cells to appear in the airways, at the expense of basal cells. The mRNA of multiciliated cell genes and the abundance of FOXJ1/SOX2+ cells increased after knockdown, whereas P63/SOX2+ cells decreased. The cytokine IL-6, a known regulator of multiciliated cell differentiation, had increased mRNA levels after QK knockdown, although protein levels remained unchanged. Further studies are necessary to confirm whether QK acts as a blocker for the IL-6-induced differentiation of basal cells into multiciliated cells, and a conditional QK knockout would likely lead to additional discoveries on QK's role during lung development.

miR-200 family expression during normal and abnormal lung development due to congenital diaphragmatic hernia at the later embryonic stage in the nitrofen rat model

INTRODUCTION

Congenital diaphragmatic hernia (CDH) is a life-threatening disease associated with pulmonary hypoplasia. CDH occurs approximately 1 in every 2000-3000 live births, and the pathophysiology is unknown. MicroRNAs are short, non-coding RNAs that control gene expression through post-transcriptional regulation. Based on our previous work, we hypothesized that the miR-200 family is differentially expressed in normal and abnormal lung development. We aimed to examine the expression of the miR-200 family during normal and hypoplastic lung development due to CDH.

METHODS

We performed reverse transcriptase polymerase chain reaction (RT-qPCR) and fluorescent in situ hybridization (FISH) to study the expression levels and distribution of the miR-200 family members on embryonic day 21 (E21) rat control and nitrofen-induced hypoplastic CDH lungs.

RESULTS

RT-qPCR showed up-regulation of miR-200a in hypoplastic CDH lungs. FISH showed contrasting expression patterns for miR- 200a, miR-200c, and miR-429 between control and hypoplastic CDH lungs, while we could not detect miR-141 in control and hypoplastic CDH lungs.

CONCLUSION

We demonstrate a specific expression pattern of miR-200 family members in hypoplastic CDH lungs different from control lungs. This study suggests that disruption of miR-200 family expression plays a role in the pathogenesis of pulmonary hypoplasia associated with CDH.

Long-Term Health-Related Quality of Life in Survivors of Congenital Diaphragmatic Hernia

The health-related quality of life (HRQoL) of survivors of congenital diaphragmatic hernia (CDH) is presently unknown. Literature prior to 2015 suggests that CDH survivors have worse HRQoL compared with the general population. However, due to changes in the diagnosis, management, and follow-up of CDH patients, this may no longer be true. The objective of this review was to determine what recent literature suggests regarding the HRQoL of CDH survivors. We reviewed all studies published between April 9, 2015, and April 6, 2020, that described the HRQoL of CDH survivors. Studies were identified using PubMed, and the references of the identified papers were searched for additional studies eligible for inclusion. Seven studies describing HRQoL in CDH survivors using validated measures of HRQoL for children, PedsQL (Pediatric Quality of Life Inventory), KIDSCREEN-52, and Comprehensive Quality of Life Scale - School Version were examined. The findings were disparate. One study suggested that CDH survivors had better than average HRQoL scores, three studies found patients and controls had equivalent scores, and two studies reported poor outcomes for CDH patients. The final study found no effect of disease severity on HRQoL, as determined by prenatal ultrasound. Evidence published between 2015 and 2020 suggests that CDH patients have an HRQoL equivalent to the general population.

Best practices for enhancing surgical research: a perspective from the Canadian Association of Chairs of Surgical Research

Summary

The Canadian Association of Chairs of Surgical Research was created in 2014, with representation from every departmental surgical research committee across Canada, to establish Canadian surgical research as a beacon for health care innovation and to propose solutions for the daily challenges facing surgeon-researchers. Our key mandate has been to identify challenges for surgeons and scientists performing research to prevent further erosion of this vital area of activity that benefits patients, health care service providers and Canadian society. This article outlines the findings of a nationwide survey sent to all members of departments of surgery across Canada, seeking input on current threats and potential solutions. The results suggest that surgical research in Canada is experiencing a decline in funding and an increase in challenges affecting research productivity of academic surgeons, such as pressures to be clinically active, unpredictable surgical schedules, growing administrative demands, and increasing complexity of patient populations. Although surgeons are productive in their research endeavours, institutional changes and sharing of best practices are needed to ensure sustainable growth of research programs.

Magnamosis for esophageal atresia is associated with anastomotic strictures requiring an increased number of dilatations

BACKGROUND/PURPOSE

Magnamosis is a novel technique which utilizes high power magnets to anastomose the esophageal ends in children with esophageal atresia (EA) with or without a tracheoesophageal fistula (TEF), theoretically avoiding the need for thoracotomy. The objective of this study was to compare anastomotic stricture formation requiring dilatation after magnamosis versus after conventional anastomosis.

METHODS

Our center treated the first 3 cases of EA ± TEF with magnamosis in Canada. One was unsuccessful and excluded from our study. The number of postintervention dilatations was compared to controls from our database, which includes all children with EA ± TEF treated between 1991 and 2015. The controls had EA ± TEF treated with pouch-to-end anastomosis or colonic interposition (n = 65). Mann-Whitney U tests were used with p < 0.05 being significant.

RESULTS

The 2 magnamosis cases had a mean of 13.5 dilatations, compared to 2.6 for the controls. Those managed with pouch-to-end anastomosis or colonic interposition had a mean of 2.3 and 2.7 dilatations, respectively. We found that the cases required more dilatations than controls (p = 0.022) and pouch-to-end anastomosis (p = 0.021), but not than colonic interposition (p = 0.106).

CONCLUSION

Our results indicate that magnamosis is associated with more postintervention dilatations than conventional anastomotic techniques, suggesting that magnamosis results in more frequent and/or more resilient anastomotic strictures.

LEVEL OF EVIDENCE

3.

Congenital diaphragmatic hernia: current management strategies from antenatal diagnosis to long-term follow-up

Congenital diaphragmatic hernia (CDH) is a developmental birth defect consisting of a diaphragmatic defect and abnormal lung development. CDH complicates 2.3-2.8 per 10,000 live births. Despite efforts to standardize clinical practice, management of CDH remains challenging. Frequent re-evaluation of clinical practices in CDH reveals that management of CDH is evolving from one of postnatal stabilization to prenatal optimization. Translational research reveals promising avenues for in utero therapeutic intervention, including fetoscopic endoluminal tracheal occlusion. These remain highly experimental and demand improved antenatal diagnostics. Timely diagnosis of CDH and identification of severely affected fetuses allow time for delivery planning or in utero therapeutics. Optimal perinatal care and surgical treatment strategies are highly debated. Improved CDH mortality rates have placed increased emphasis on identifying and monitoring the long-term sequelae of disease throughout childhood and into adulthood. We review the current management strategies for CDH, highlighting where progress has been made, and where future developments have the potential to revolutionize care in this vulnerable patient population.

Basic and translational science advances in congenital diaphragmatic hernia

Congenital Diaphragmatic Hernia (CDH) is a birth defect that is characterized by lung hypoplasia, pulmonary hypertension and a diaphragmatic defect that allows herniation of abdominal organs into the thoracic cavity. Although widely unknown to the public, it occurs as frequently as cystic fibrosis (1:2500). There is no monogenetic cause, but different animal models revealed various biological processes and epigenetic factors involved in the pathogenesis. However, the pathobiology of CDH is not sufficiently understood and its mortality still ranges between 30 and 50%. Future collaborative initiatives are required to improve our basic knowledge and advance novel strategies to (prenatally) treat the abnormal lung development. This review focusses on the genetic, epigenetic and protein background and the latest advances in basic and translational aspects of CDH research.

Asthma Medication Use in Congenital Diaphragmatic Hernia Survivors: A Retrospective Population Level Data Analysis

INTRODUCTION

 The purpose of this study was to determine if congenital diaphragmatic hernia (CDH) survivors had worse long-term respiratory outcomes compared with age-matched controls, as measured by inhaled bronchodilator use, inhaled steroid use, and asthma-related physician visits.

MATERIALS AND METHODS

 We performed a retrospective case-control study of infants with isolated CDH from 1991 to 2013. The primary outcome measures were inhaled bronchodilator prescriptions, inhaled steroid prescriptions, and asthma-related physician visits between 0 and 5 years of age and between 5 and 10 years of age. Subgroup analysis compared the same outcomes for CDH patients grouped by: birth weight, gestational age, side of defect, defect size, liver herniation, hernia sac, and pulmonary hypertension.

RESULTS

 Fifty-six patients with CDH and 753 age-matched controls met the inclusion criteria for the 0 to 5 years of age analysis. Between 0 and 5 years of age, more CDH survivors were prescribed an inhaled bronchodilator (odds ratio [OR] = 2.47[1.38-4.48], p = 0.001) and inhaled steroid (OR = 2.03[1.07-3.74], p = 0.03), and had an asthma-related physician visit (OR = 1.92[1.00-3.56], p = 0.04). Thirty-eight cases and 491 controls met the inclusion criteria for the 5 to 10 years of age analysis. Between 5 and 10 years of age, CDH survivors were not more likely to be prescribed inhaled bronchodilators, inhaled steroids, or have an asthma-related physician visit. Among the CDH patients, we did not find a clinical characteristic associated with increased inhaled bronchodilator or steroid prescriptions at any age.

CONCLUSION

 A history of CDH is associated with higher rates of inhaled bronchodilator prescriptions, inhaled steroid prescriptions, and asthma-related physician visits from 0 to 5 years of age compared with age-matched controls. However, this difference resolves by 5 to 10 years of age.

First steps in the development of a liquid biopsy in situ hybridization protocol to determine circular RNA biomarkers in rat biofluids

PURPOSE

Epigenetic factors are involved in the pathogenesis of congenital diaphragmatic hernia (CDH). Circular RNAs (circRNAs) are epigenetic regulators amenable to biomarker profiling. Here, we aimed to develop a liquid biopsy protocol to detect pathognomonic circRNA changes in biofluids.

METHODS

Our protocol is adapted from the existing BaseScope™ in situ hybridization technique. Rat biofluids were fixed in a gelatin-coated 96-well plate with formalin. Probes were designed to target circRNAs with significant fold change in nitrofen-induced CDH. FastRED fluorescence was assessed using a plate reader and confirmed with confocal microscopy. We tested maternal serum and amniotic fluid samples from control and nitrofen-treated rats.

RESULTS

We detected circRNAs in rat serum and amniotic fluid from control and CDH (nitrofen-treated) rats using fluorescent readout. CircRNA signal was observed in fixed biofluids as fluorescent punctate foci under confocal laser scanning microscopy. This was confirmed by comparison to BaseScope™ lung tissue sections. Signal was concentration dependent and DNase resistant.

CONCLUSION

We successfully adapted BaseScope™ to detect circRNAs in rat biofluids: serum and amniotic fluid. We detected signal from probes targeted to circRNAs that are dysregulated in rat CDH. This work establishes the preliminary feasibility of circRNA detection in prenatal diagnostics.

Establishment of a biobank for human lung tissues of congenital diaphragmatic hernia and congenital pulmonary airway malformation

BACKGROUND

Human tissue samples are an invaluable and little available source of information for translational studies of congenital lung diseases such as Congenital Diaphragmatic Hernia (CDH) or Congenital Pulmonary Airway Malformation (CPAM).

PURPOSE

We aimed to establish a human lung tissue biobank of CDH and CPAM patients together with age-matched controls, coupled with a clinical database.

METHODS

Pathology records from autopsies or surgical specimens for CDH and CPAM cases between 1980 and 2017 were reviewed. For surviving individuals, clinical patient data was obtained from corresponding pediatric surgery reports. Formalin-fixed, paraffin-embedded tissues of patients and age-matched controls were systematically stored for further translational studies. RNA integrity was determined on selected CDH blocks.

RESULTS

A total of 16 CDH and 18 CPAM and age-matched control lung tissue blocks were included in our biobank. Ages ranged from 22 to 41 weeks of gestation (GA) in CDH (33.9 ± 6.35 weeks) and 26 weeks (GA) and 12 years in CPAM (2.3 ± 3.7 y). RNA isolation from CDH and control blocks yielded good RNA quality (OD 260/280 ratio: 2.01-2.09, OD 260/230 ratio: 2.04-2.09).

CONCLUSION

We established a unique human biobank for CDH and CPAM tissues. The combination with clinical patient data will allow us to design future translational studies to improve our understanding of the disease pathogenesis of these congenital malformations.

The presence of a hernia sac in isolated congenital diaphragmatic hernia is associated with less disease severity: A retrospective cohort study

INTRODUCTION

We aimed to determine if the presence of a hernia sac in neonates with isolated congenital diaphragmatic hernia (CDH) was associated with better clinical outcomes.

METHODS

We performed a retrospective cohort study of infants with isolated CDH from 1991 to 2015. Primary outcome measures were oxygen-dependence and mortality at 28 days. Secondary measures were: inhaled nitric oxide use, vasoactive medication use, ventilator support, and recurrence rates.

RESULTS

Seventy-one patients met the inclusion criteria: 14 patients (19.7%) had a hernia sac, and 57 patients (80.3%) did not. Mortality did not differ between the 2 groups [0 of 14 versus 3 of 57 (5.3%) (p = 1.000)]. Hernia sac patients had similar oxygen-dependence after 28 days [1 of 14 (7.1%) versus 14 of 57 (24.6%) (p = 0.273)]. Hernia sac children required less iNO (0.64 ± 2.41 vs. 6.35 ± 12.2 days, p = 0.002), vasoactive medications (2.79 ± 3.07 vs. 5.36 ± 5.52, p = 0.027), and time on ventilation (7.62 ± 6.12 vs. 15.9 ± 19.2, p = 0.010). Hernia sac children had similar recurrence rates within 2 years [0 of 14 versus 7 of 57 (12.3%) (p = 0.331)].

CONCLUSION

The presence of a hernia sac was not associated with lower rates of oxygen dependency or death at 28 days but was associated with decreased inhaled nitric oxide, vasoactive medication, and ventilator use.

LEVEL OF EVIDENCE

III.

Identifying Information Needs for Hirschsprung Disease Through Caregiver Involvement via Social Media: A Prioritization Study and Literature Review

Background

Patient and public involvement in health research is important to produce relevant and impactful results.

Objective

This paper aimed to prioritize and summarize Hirschsprung disease (HD)–related information needs among caregivers of children with HD and pediatric surgeons through partnership with a parent-initiated social media campaign.

Methods

We conducted a Web-based survey with the 2 stakeholder groups to identify information needs. The caregiver survey was conducted through a global Web-based community, and the surgeon survey was distributed to members of the Canadian Association of Paediatric Surgeons (CAPS). We conducted a literature review to identify evidence on the prioritized topics.

Results

Our findings showed that 54.9% (89/162) of the individuals completed the caregiver survey and 23.8% (52/218 listed members) of the pediatric surgeons completed the survey distributed through CAPS. Only 20% (18/89) of the caregivers reported being very satisfied or satisfied with the current HD-related resources. A final prioritized list of information needs included bowel management, nutrition and growth, infection, perianal irritation, gastrointestinal pain, surgical diagnostics, and surgical complications. In total, 87 studies were included in the literature review, which included the following: 8 reviews, 2 randomized controlled trials, 74 cohort studies, and 3 practice guidelines. Two priority issues identified by caregivers had only a single study that met the inclusion criteria, whereas 1 topic had none.

Conclusions

With caregiver and surgeon input, we identified 7 information priority areas related to HD. A review of the literature on the priorities found little evidence to support the development of high-quality guidelines. More research is necessary to meet the information needs related to HD as identified by stakeholders.

MicroRNA 200b is upregulated in the lungs of fetal rabbits with surgically induced diaphragmatic hernia

OBJECTIVE

Profiling of miR-200b expression and its targets (transforming growth factor [TGF]-β2 and ZEB2) in the surgical rabbit congenital diaphragmatic hernia (DH) model before and after tracheal occlusion (TO).

METHODS

Thirty-eight timed-pregnant rabbits had left DH creation on gestational day (GD) 23. On GD28, 17 randomly selected fetuses had TO. We harvested fetuses at GD23, GD28, or GD30. We calculated lung-to-body weight ratios, processed lungs for miR-200b in situ hybridization and real-time quantitative polymerase chain reaction, and evaluated effects on downstream targets TGF-β2 or ZEB2.

RESULTS

We obtained 16 DH fetuses (n = 7 GD28 and n = 9 GD30), 13 TO fetuses (GD30), and 38 control fetuses (n = 15 GD23, n = 11 GD28, and n = 12 GD30). Diaphragmatic hernia lungs were hypoplastic, and TO resulted in control lung-to-body weight ratio levels. Term miR-200b-3p levels were significantly upregulated in the hypoplastic compared with control ipsilateral lung (1.906 ± 0.90 vs 0.7429 ± 0.44) (P < .01). Fetal TO ipsilateral lungs displayed a variable miR-200b response on in situ hybridization and polymerase chain reaction, with levels similar to control and congenital DH lungs. The TGF-β2 was unchanged in hypoplastic and TO lungs, and ZEB2 tended to be reduced in TO compared with DH lungs (1.79 [0.4-2.9] vs 0.73 [0.5-1.4]).

CONCLUSIONS

Hypoplastic fetal rabbit lungs display upregulation of miR-200b expression although downstream targets are not different from controls. Following TO, fetal rabbit lungs display a variable miR-200b response.

Myocardin regulates mitochondrial calcium homeostasis and prevents permeability transition

Myocardin is a transcriptional co-activator required for cardiovascular development, but also promotes cardiomyocyte survival through an unclear molecular mechanism. Mitochondrial permeability transition is implicated in necrosis, while pore closure is required for mitochondrial maturation during cardiac development. We show that loss of myocardin function leads to subendocardial necrosis at E9.5, concurrent with elevated expression of the death gene Nix. Mechanistically, we demonstrate that myocardin knockdown reduces microRNA-133a levels to allow Nix accumulation, leading to mitochondrial permeability transition, reduced mitochondrial respiration, and necrosis. Myocardin knockdown elicits calcium release from the endo/sarcoplasmic reticulum with mitochondrial calcium accumulation, while restoration of microRNA-133a function, or knockdown of Nix rescues calcium perturbations. We observed reduced myocardin and elevated Nix expression within the infarct border-zone following coronary ligation. These findings identify a myocardin-regulated pathway that maintains calcium homeostasis and mitochondrial function during development, and is attenuated during ischemic heart disease. Given the diverse role of Nix and microRNA-133a, these findings may have broader implications to metabolic disease and cancer.