CRISPRi-mediated functional analysis of lung disease-associated loci at non-coding regions.

Genome-wide association studies have identified lung disease-associated loci; however, the functions of such loci are not well understood in part because the majority of such loci are located at non-coding regions. Hi-C, ChIP-seq and eQTL data predict potential roles (e.g. enhancer) of such loci; however, they do not elucidate the molecular function. To determine whether these loci function as gene-regulatory regions, CRISPR interference (CRISPRi; CRISPR/dCas9-KRAB) has been recently used. Here, we applied CRISPRi along with Hi-C, ChIP-seq and eQTL to determine the functional roles of loci established as highly associated with asthma, cystic fibrosis (CF), chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF). Notably, Hi-C, ChIP-seq and eQTL predicted that non-coding regions located at chromosome 19q13 or chromosome 17q21 harboring single-nucleotide polymorphisms (SNPs) linked to asthma/CF/COPD and chromosome 11p15 harboring an SNP linked to IPF interact with nearby genes and function as enhancers; however, CRISPRi indicated that the regions with rs1800469, rs2241712, rs12603332 and rs35705950, but not others, regulate the expression of nearby genes (single or multiple genes). These data indicate that CRISPRi is useful to precisely determine the roles of non-coding regions harboring lung disease-associated loci as to whether they function as gene-regulatory regions at a genomic level.

In harm's way: Unintentional firearm injuries in young children.

PURPOSE: Firearm-related trauma represents a major source of preventable injury and death. Many firearm injuries in young children are unintentional, and the true incidence may be underestimated. We sought to characterize the morbidity of unintentional firearm injuries. METHODS: National Trauma Data Bank data from 2007 to 2014 was obtained for patients aged 0-14 sustaining gunshot wounds (GSW). We analyzed demographics, injury severity score, hospital and ICU length of stay (LOS), ventilator days, discharge to rehab, and mortality. We categorized intention as assault, unintentional, self-inflicted or other, and compared unintentional firearm injuries against all others using Student's t test or chi-square analysis. RESULTS: We identified 7487 GSW patients aged 0-14, of whom 2514 (33.6%) sustained unintentional injuries. The mortality rate for unintentionally injured patients was 9.2%, compared with 14.2% for all other intentions (p<0.0001). Unintentionally injured children were more likely to be male (p=0.01) and Caucasian (p<0.0001) and had lower rates of ICU admission (p=0.02), ventilator use (p=0.0004), and discharge to rehab (p<0.0001). CONCLUSIONS: Unintentional injuries comprise one-third of firearm injuries and approximately 10% of GSW-related mortality in young children. Since these injuries are entirely preventable, our findings suggest a major opportunity to reduce disease burden. LEVEL OF EVIDENCE: IV.

Comparison of the Lund and Browder table to computed tomography scan three-dimensional surface area measurement for a pediatric cohort.

BACKGROUND: Treating burns effectively requires accurately assessing the percentage of the total body surface area (%TBSA) affected by burns. Current methods for estimating %TBSA, such as Lund and Browder (L&B) tables, rely on historic body statistics. An increasingly obese population has been blamed for increasing errors in %TBSA estimates. However, this assumption has not been experimentally validated. We hypothesized that errors in %TBSA estimates using L&B were due to differences in the physical proportions of today's children compared with children in the early 1940s when the chart was developed and that these differences would appear as body mass index (BMI)-associated systematic errors in the L&B values versus actual body surface areas. MATERIALS AND METHODS: We measured the TBSA of human pediatric cadavers using computed tomography scans. Subjects ranged from 9 mo to 15 y in age. We chose outliers of the BMI distribution (from the 31st percentile at the low through the 99th percentile at the high). We examined surface area proportions corresponding to L&B regions. RESULTS: Measured regional proportions based on computed tomography scans were in reasonable agreement with L&B, even with subjects in the tails of the BMI range. The largest deviation was 3.4%, significantly less than the error seen in real-world %TBSA estimates. CONCLUSIONS: While today's population is more obese than those studied by L&B, their body region proportions scale surprisingly well. The primary error in %TBSA estimation is not due to changing physical proportions of today's children and may instead lie in the application of the L&B table.

Validation of the age-adjusted shock index using pediatric trauma quality improvement program data.

PURPOSE: In adults, shock index (SI; heart rate/systolic blood pressure) >0.9 predicts injury severity and trauma outcomes. However, age-adjusted shock index (SIPA) out-performs SI in blunt trauma patients 4-16years old. We sought to confirm these findings and expand this tool to include penetrating trauma and children aged 1-4years. METHODS: We developed cutoff values for patients 1-3years old using age-based vital signs and queried the 2014 Pediatric Trauma Quality Improvement Program (TQIP) database for patients aged 1-16years sustaining blunt or penetrating trauma. Outcomes measured included injury severity, transfusion within 24h, intensive care unit (ICU) and hospital length of stay (LOS), and mortality. SI and SIPA were compared using Student's t-test and chi-square tests. RESULTS: We identified 22,344 blunt and 613 penetrating trauma patients. SI was elevated in 41.3% and 40.0% of these groups, respectively, whereas SIPA was elevated in 15.6% and 19.4% of patients. SIPA was a significantly better predictor of transfusion needs, injury severity, ICU admission, ventilator use, and mortality for both blunt and penetrating trauma. CONCLUSION: SIPA identifies severe injury and predicts transfusion needs and mortality more effectively than SI for both blunt and penetrating pediatric trauma. Further investigation should evaluate its use as a triage tool. TYPE OF STUDY: Prognosis Study. LEVEL OF EVIDENCE: II.

Pediatric aortoiliac injury following blunt abdominal trauma: A case report.

INTRODUCTION: The most common mechanism of aortic injury involves motor vehicle collisions resulting in aortic disruptions, occurring almost exclusively in the chest. Injury to the abdominal aorta following blunt trauma is nearly twenty times less likely to occur than the thoracic aorta. Because of the low incidence, there are few reports regarding the presentation and repair of these particular injuries, especially in the pediatric population. PRESENTATION OF CASE: We present a case of a 7-year-old boy involved in a high speed motor vehicle accident with an abdominal aorta transection at the aortic bifurcation extending into the left iliac artery. The injury was repaired using bovine pericardium with the adventitia and intima of the vessel approximated over the bovine bridge. DISCUSSION: Primary repair of thoracic aortic injury has been thoroughly described in the literature with good outcomes yet, abdominal aortic repair remains ambiguous. Few techniques and materials have been described with even less data surrounding the long-term outcomes. CONCLUSION: Bovine pericardium is a strong and stable acellular collagenous material with the potential to accelerate endothelialization and tissue regeneration. This remains an interesting field of research as stenosis and pseudo-coarction data have yet to be determined.

Tracheal occlusion and ventilation changes the nitric oxide pathway in congenital diaphragmatic hernia model.

BACKGROUND: Congenital diaphragmatic hernia (CDH) is associated with lung hypoplasia and pulmonary hypertension. Tracheal occlusion (TO) stimulates fetal lung growth and maturation and reverse vascular changes responsible for pulmonary hypertension, which are related to mechanisms involving nitric oxide (NO) in CDH. We aim to evaluate the effect of TO and ventilation on NO pathways. METHODS: Eight groups were created: (1) control; (2) control ventilated (CV); (3) CDH (CDH); (4) CDH ventilated (CDHV); (5) TO control; (6) TO ventilated; (7) TO + CDH; and (8) TO + CDH ventilated (CDHTOV). Fetuses were weighed, and volume ventilated for 30 min after harvested. Total lung weight and the ratio of total lung weight to body weight, thickness of the middle layer of the pulmonary arteriole, and the air space diameter were measured. The NO synthase inducible and NO synthase inducible were performed by immunohistochemistry and Western blotting. RESULTS: The total lung weight and the ratio of total lung weight to body weight decreased in animals with nitrofen and also after ventilation for all groups (P < 0.05). The thickness of the middle layer of the pulmonary arteriole decreased in all groups with TO when compared with controls (P < 0.001). The air space diameter decreased after ventilation in the CDHTOV compared to the TO + nitrofen-induced CDH (P < 0.001). Compared to nonventilated cohorts, NO synthase inducible increased in CV and TO ventilated (P < 0.001) and decreased in CDHV and CDHTOV (P < 0.001). NO synthase inducible increased in CV and CDHV (P < 0.001) and decreased in the TO control and CDHTOV (P < 0.001). CONCLUSIONS: TO and ventilation alter the NO pathway with possible implications in reducing the pulmonary hypertension in CDH.

Prenatal Diagnosis of Infantile Myofibroma with Postnatal Imaging Correlation.

Infantile myofibroma is the most common fibrous tumor in infancy. A majority of these lesions are solitary and occur in the head and neck region. Unless visceral sites are involved, the clinical course is typically benign. However, the difficulty in these cases is the differentiation of a benign myofibroma from a solitary malignant neoplasm and determination of visceral involvement. Prenatal diagnosis of this condition is rarely described in the literature, but it does indeed have a role in perinatal management. Our patient was initially identified by prenatal ultrasound with fetal MRI for further characterization of the mass. We present the case of a prenatally diagnosed solitary infantile myofibroma of the lower extremity and highlight the role of prenatal imaging in the diagnosis and treatment of this condition.

Fetal MRI of Torsed Bronchopulmonary Sequestration with Tension Hydrothorax and Hydrops in a Twin Gestation.

While bronchopulmonary sequestration typically has a benign course, this congenital lung malformation has a high mortality rate when associated with untreated in utero tension hydrothorax and hydrops. Hydrops related to bronchopulmonary sequestration is believed to result from torsion of the mass with compromise of the associated blood supply. The impaired venous return of the mass then leads to tension hydrothorax with compression of the heart and mediastinal vessels, impairing global venous return. To our knowledge, this scenario has only been described prenatally by ultrasound. We present the imaging findings of a dichorionic, diamniotic twin gestation with one fetus developing tension hydrothorax and hydrops from presumed intermittent torsion of a bronchopulmonary sequestration. This diagnosis was only able to be confirmed by MRI prior to the use of ultrasound-guided interstitial laser photocoagulation for the treatment of this anomaly.

Pleuropulmonary Blastoma in a Neonate Diagnosed Prenatally as Congenital Pulmonary Airway Malformation.

Pleuropulmonary blastoma is an extremely rare lung neoplasm exclusive to children under 5 years of age. It presents a diagnostic challenge both prenatally and in early childhood due to its similarity to benign lung cysts, which are managed differently. We present the first case, to our knowledge, of a neonate with pleuropulmonary blastoma and myelomeningocele, though prenatally diagnosed as a congenital pulmonary airway malformation. We detail the prenatal imaging that facilitated counseling and delivery management in addition to the correlating postnatal imaging.

Differential patterns of prenatal ipsilateral and contralateral lung growth in cases of isolated left-sided congenital diaphragmatic hernia.

OBJECTIVE: The aim of this research was to compare the impact of varying degrees of visceral herniation on the growth rates of the contralateral and ipsilateral fetal lungs in cases of isolated left-sided congenital diaphragmatic hernia (CDH). METHODS: Data were retrieved from 58 fetuses with isolated left-sided CDH undergoing magnetic resonance imaging studies at both mid-gestation (20-30 weeks) and late-gestation (>30 weeks) time points. The growth of the right and left lungs (ΔLV-R and ΔLV-L) was calculated. The impact of the degree of visceral herniation on the growth disparity between the right and left lungs was then compared. RESULTS: Measurable growth occurred in both lungs between the mid-gestation and late-gestation time points in each group. The ΔLV-R exhibited a strong correlation with ΔLV-L. However, the right lung grew significantly faster than the left lung (ΔLV-R = 1.36 vs ΔLV-L = 0.17 mL/week, P < 0.001). A higher degree of visceral herniation appeared to decrease the growth rate disparity by progressive limitation of the growth of the right lung. CONCLUSION: The contralateral lung retains the potential to grow faster than the ipsilateral lung during the third trimester. A higher degree of visceral herniation places progressive limitations on contralateral lung growth thereby diminishing the growth rate disparity between the right and left lungs.

Predictors of poor prognosis in prenatally diagnosed sacrococcygeal teratoma: A multiinstitutional review.

INTRODUCTION: Attempts at defining predictors of poor outcome in fetal sacrococcygeal teratoma (SCT) have been hampered by small patient numbers. We sought to validate the utility of tumor volume to fetal weight ratio (TFR) as a predictor of poor prognosis and to identify other morphological outcome predictors in a multicenter series. METHODS: Records of prenatally diagnosed SCT at three fetal centers from 1986 to 2011 were reviewed. Prenatal imaging characteristics including TFR, morphology, hydrops, and placentomegaly were assessed. Poor prognosis was defined as fetal demise, need for fetal intervention, or perinatal death. Receiver operating characteristic (ROC) analysis was used to select a TFR cutoff value. RESULTS: Seventy-nine fetuses with SCT were evaluated. Eleven pregnancies ending in elective termination were excluded. ROC analysis revealed that TFR >0.12 prior to 24 weeks gestation was predictive of poor prognosis (AUC=0.913; Sensitivity=91.7%, Specificity=76.2%, PPV=86.8%; NPV=84.2%). Solid tumor morphology and presence of hydrops were found to be predictors of poor prognosis. None of the factors associated with poor prognosis were independent predictors on multivariate analysis. CONCLUSION: This study validates TFR >0.12 prior to 24 weeks gestation as an objective predictor of outcomes in fetuses with SCT that can be easily applied in most clinical settings.

Expanded intrathoracic space in fetal cases of isolated congenital diaphragmatic hernia contributes to disparity between percent predicted lung volume and observed to expected total lung volume.

OBJECTIVE: The aim of this study was to determine whether fetal lung volume and visceral herniation are associated with changes in intrathoracic space in congenital diaphragmatic hernia(CDH). METHODS: We retrospectively examined the relationship between magnetic resonance imaging-derived measurements of intrathoracic space [predicted lung volume (PLV)] and residual lung volume or visceral herniation among isolated left-sided CDH fetuses. RESULTS: Data from fetal magnetic resonance imaging studies of 60 isolated left-sided CDH cases were analyzed. The median PLV of the CDH fetuses was found to be much greater than the expected total lung volume (eTLV) of a normal fetus at the same gestational age. Surprisingly, liver herniation and observed TLV(oTLV) were positively correlated with the PLV. Although the PPLV was consistently less than the o/eTLV, both indices were greater in survivors than in non-survivors, whereas no significant difference was seen in the PLV/eTLV ratio in regard to survivorship. CONCLUSION: The intrathoracic domain available for lungs and viscera is expanded in CDH fetuses and positively affected by the lung volume and the presence of liver herniation, leading to the difference in the PPLV and o/eTLV. Future study of intrathoracic space as it relates to the growth of the lung and herniated viscera is needed to better characterize the relationship between these parameters.

Fetal lung growth represented by longitudinal changes in MRI-derived fetal lung volume parameters predicts survival in isolated left-sided congenital diaphragmatic hernia.

OBJECTIVE: The aim of this study was to evaluate fetal lung growth rate for isolated left-sided congenital diaphragmatic hernia (CDH) using serial magnetic resonance imaging (MRI)-based volumetric measures. METHODS: Early and late gestational (22-30 and >30 weeks' gestation) lung volumetry was obtained by fetal MRI in 47 cases of isolated left-sided CDH. At both of these time points, lung volume indices, including total lung volume (TLV), observed to expected TLV (o/e TLV), and percentage of predicted lung volume (PPLV) as well as their change rates (Δ) and relative Δ during gestation were calculated and analyzed in regard to their capacity to predict neonatal survival. RESULTS: TLV, o/e TLV, and PPLV had various changes during gestation. Late TLV, early and late o/e TLV, and late PPLV were predictive of neonatal survival. Non-survivors had lower ΔTLV and more negative relative ΔPPLV than survivors (1.18 vs 1.85 mL/week, P = 0.004 and -4.15%/week vs -1.95%/week, P = 0.002, respectively). CONCLUSIONS: The severity of pulmonary hypoplasia is dynamic and can worsen in the third trimester. MRI lung volumetry repeated in late gestation can provide additional information on individual lung growth that may facilitate prenatal counseling and focus perinatal management.

Altered amniotic fluid leptin levels in twin-twin transfusion syndrome with concurrent placental insufficiency.

OBJECTIVE: To measure amniotic fluid leptin levels in fetuses with twin-twin transfusion syndrome (TTTS) with and without placental insufficiency (PI) and determine its usefulness as a biomarker of PI. STUDY DESIGN: A retrospective case control study of TTTS stage III patients from 2009 to 2011 was conducted. Cases were pregnancies with PI (TTTS-PI, n = 18) matched by stage, gestational age, and degree of cardiomyopathy to controls without PI (TTTS, n = 26). PI was strictly defined using biometric parameters. Amniotic fluid from recipient twins (RT) was taken during second trimester fetoscopic laser therapy. Leptin concentrations were determined and compared to growth parameters and birth weight. RESULTS: RT-adjusted leptin was 66% higher in TTTS-PI (p = 0.016) compared to TTTS controls. Cases had significantly higher growth discordance (p = 0.004) and lower RT birth weight (p = 0.041) compared to controls. Significantly higher adjusted leptin levels were observed at birth in the TTTS-PI group when comparing those with SGA donor twins to those of normal weight (p = 0.016). CONCLUSION: These data suggest a role for leptin in pregnancies complicated by TTTS with placental insufficiency. However, further studies are needed to define its mechanism and potential role as a biomarker in amniotic fluid for placental pathophysiology.

Giant chorioangiomas: perinatal outcomes and techniques in fetoscopic devascularization.

OBJECTIVE: To evaluate the intrauterine management and perinatal outcome of pregnancies complicated by giant placental chorioangioma (>4 cm) and elaborate on various devascularization techniques. MATERIALS AND METHODS: Retrospective review of 10 cases of giant placental chorioangioma evaluated between January 2005 and August 2012. Maternal demographics, prenatal imaging, response to fetoscopic treatment, obstetrical complications, and perinatal outcomes were evaluated. RESULTS: Overall survival was 80%. Seven (70%) cases were associated with obstetrical complications, including polyhydramnios (n = 7), non-immune hydrops (n = 3), and high cardiac output state (n = 5). Five patients underwent fetoscopic devascularization at a mean gestational age of 24.03 weeks with 80% survival. The tumors were devascularized by bipolar coagulation (n = 1), combination of bipolar and diode laser (n = 2), bipolar and radiofrequency ablation (n = 1), and surgical clip application (n = 1). Postoperatively, all survivors had resolution of hydrops and high cardiac output states with survival beyond 60 days of life. DISCUSSION: Fetoscopic devascularization is indicated for high cardiac output states or non-immune hydrops and may require multiple techniques including bipolar coagulation, clip application, and/or laser to interrupt arterial inflow and devascularize the mass.

Sacrococcygeal teratoma growth rate predicts adverse outcomes.

PURPOSE: The purpose of this study was to characterize the growth rate of sacrococcygeal teratomas (SCTs) and determine its relationship to adverse outcomes. METHODS: A retrospective review of all pathology-confirmed isolated SCT patients evaluated with at least two documented ultrasounds and followed through hospital discharge between 2005 and 2012 was conducted. SCT growth rate was calculated as the difference between tumor volumes on a late- and early-gestation ultrasound divided by the difference in time. Outcomes were death, high-output cardiac failure (HOCF), hydrops, and preterm delivery. Student's t-test, receiver operator characteristics, Fisher's Exact test, and Pearson's correlation were performed. RESULTS: Of the 28 study subjects, there were 3 in utero demises and 2 neonatal deaths. Significantly faster SCT growth rates were seen in all adverse outcomes, including death (p<0.0001), HOCF (p=0.005), and preterm delivery (p=0.009). There was a significant association with adverse outcomes at >61cm(3)/week (AUC=0.87, p=0.001, LR=4.52). Furthermore, there was an even greater association with death at >165cm(3)/week (AUC=0.93, p=0.003, LR=18.42). Growth rate was directly correlated with the percent of solid tumor (r=0.60, p=0.0008). CONCLUSION: Faster SCT growth is associated with adverse outcomes. SCT growth rate determined by ultrasound is an effective prognostic indicator for adverse outcomes and easily applied to patient management.

Prenatal solid tumor volume index: novel prenatal predictor of adverse outcome in sacrococcygeal teratoma.

BACKGROUND: Sacrococcygeal teratoma is the most common neonatal tumor. Fetuses with large tumors may develop hydrops from a high cardiac output state (HCOS) and progress rapidly to fetal demise. We postulate that the prenatal solid tumor volume index (STVI), or the ratio of solid tumor volume to the estimated fetal weight (EFW), has greater impact than the total tumor volume in outcome prediction. METHODS: A retrospective chart review of all sacrococcygeal teratoma patients (n = 38) between 2005 and 2012 was conducted. Total tumor volume and percent of solid component were calculated by magnetic resonance imaging and then normalized by dividing them by either head circumference or EFW. Outcomes measured were survival, hydrops or high cardiac output state, defined as a combined ventricular output of >625 mL/min/kg with abnormal Doppler or echocardiogram findings. RESULTS: Thirty-one patients were included in the study. All deaths (n = 7) had either high cardiac output state or hydrops. At a total tumor volume/EFW >0.16, the patient was 17 times more likely to develop HCOS/hydrops (P = 0.001) with 81.25% sensitivity and 86.67% specificity. At a STVI >0.09, the patient was 120 times more likely to develop HCOS/hydrops (P < 0.0001) with 81.25% sensitivity and 100% specificity. CONCLUSIONS: While total tumor volume aids in stratifying patients into high risk categories, STVI (solid tumor volume/EFW) is a better predictor of adverse outcomes. This data will allow us to identify patients who are high risk for cardiac compromise and guide appropriate therapy.

Tracheal agenesis with tracheoesophageal fistulae: fetal MRI diagnosis with confirmation by ultrasound during an ex utero intrapartum therapy (EXIT) delivery and postdelivery MRI.

Tracheal agenesis is a rare and essentially lethal anomaly with divergent prenatal imaging findings depending on the presence or absence of a tracheoesophageal fistula. All prenatally diagnosed cases of tracheal agenesis reported to date have not had a tracheoesophageal fistula and presented with thoracoabdominal findings similar to congenital high airway obstruction syndrome. We present the case of a 32-week gestation fetus with rapid onset of polyhydramnios and no persistent findings of congenital high airway obstruction syndrome that was ultimately diagnosed with tracheal agenesis plus tracheoesophageal fistula by fetal MRI. Additionally, we present the novel uses of intraoperative US during a staged ex utero intrapartum therapy delivery and postdelivery MRI, facilitated by proximity within the neonatal ICU, to confirm diagnosis and direct patient management while minimizing unnecessary investigations.

Cooking-related pediatric burns: risk factors and the role of differential cooling rates among commonly implicated substances.

Cooking-related injuries are a common problem worldwide, resulting in more pediatric burns than any other cause. We identified risk factors-associated mechanisms and determined cooling curves for common substances. A retrospective review of children admitted to a Level I burn center between 2001 and 2006 was performed. Variables including injury mechanism, age, sex, race, burn area, length of stay, and outcome were recorded. Commonly implicated substances were identified, and cooling curves for each were measured at room temperature. Logistic regression analysis was performed to identify risk factors for cooking injury. A total of 541 pediatric burn patients were admitted, of whom 123 had cooking-related injuries. Common substances involved included soup (27%), grease (26%), coffee (18%), beans (9%), and menudo (2.3%), a traditional Mexican soup based on tripe, hominy, and chile. Children with cooking injuries were significantly younger than other groups, with a mean age of 2.7 years. The most common mechanism was the child pulling the substance down from a height, accounting for nearly half of all injuries. This resulted in a characteristic scald pattern involving a wide area across chest and shoulders narrowing to a point near the pelvis. The average burn area was 7%, associated with a hospital stay of 4 days and mortality below 1%. Analysis of cooling curves revealed surprising variation in heat retention, with semisolid or high-density liquids posing a markedly increased burn risk. Cooking injuries predominantly affect toddlers, with clearly recognized mechanisms and risk factors. Injury prevention measures should be targeted accordingly.