First genome-wide association study of esophageal atresia identifies three genetic risk loci at CTNNA3, FOXF1/FOXC2/FOXL1, and HNF1B.

Esophageal atresia with or without tracheoesophageal fistula (EA/TEF) is the most common congenital malformation of the upper digestive tract. This study represents the first genome-wide association study (GWAS) to identify risk loci for EA/TEF. We used a European case-control sample comprising 764 EA/TEF patients and 5,778 controls and observed genome-wide significant associations at three loci. On chromosome 10q21 within the gene CTNNA3 (p = 2.11 × 10-8; odds ratio [OR] = 3.94; 95% confidence interval [CI], 3.10-5.00), on chromosome 16q24 next to the FOX gene cluster (p = 2.25 × 10-10; OR = 1.47; 95% CI, 1.38-1.55) and on chromosome 17q12 next to the gene HNF1B (p = 3.35 × 10-16; OR = 1.75; 95% CI, 1.64-1.87). We next carried out an esophageal/tracheal transcriptome profiling in rat embryos at four selected embryonic time points. Based on these data and on already published data, the implicated genes at all three GWAS loci are promising candidates for EA/TEF development. We also analyzed the genetic EA/TEF architecture beyond the single marker level, which revealed an estimated single-nucleotide polymorphism (SNP)-based heritability of around 37% ± 14% standard deviation. In addition, we examined the polygenicity of EA/TEF and found that EA/TEF is less polygenic than other complex genetic diseases. In conclusion, the results of our study contribute to a better understanding on the underlying genetic architecture of ET/TEF with the identification of three risk loci and candidate genes.

Development of a prediction model for postoperative complications after primary hypospadias correction.

PURPOSE: To develop a prediction model for postoperative complications after primary one-stage hypospadias correction to improve preoperative parental counseling. MATERIALS AND METHODS: In this retrospective cohort study, data were collected from 356 patients with anterior or middle hypospadias who had a one-stage hypospadias correction from 2003 onwards. Potential treatment- and patient-related factors were selected and used to develop a prediction model for postoperative complications within one year (wound-related complications, urinary tract infections, fistulas, stenosis, and prepuce-related complications). Multivariable logistic regression analysis with stepwise backward selection and a p-value of 0.20 was used to select the final model, which was internally validated using the bootstrap procedure. RESULTS: Complications within one year postoperatively occurred in 66 patients (19%), of which 13% and 37% were seen in anterior and middle type of hypospadias, respectively. Hypospadias phenotype, surgical technique, chordectomy, and surgeon's experience were included in the final prediction model, whereas none of the patient-related factors were. The final model had a good discriminative ability (bias corrected C statistic 0.70) and calibration. CONCLUSION: Using easily obtainable information, this model showed good accuracy in predicting complications within one year after hypospadias surgery. It is a first step towards individualized risk prediction of postoperative complications for anterior and middle hypospadias and can assist in preoperative parental counseling. TYPE OF STUDY: Prognostic study. LEVEL OF EVIDENCE: Level II.

Non-Syndromic Cleft Lip with or without Cleft Palate: Genome-Wide Association Study in Europeans Identifies a Suggestive Risk Locus at 16p12.1 and Supports SH3PXD2A as a Clefting Susceptibility Gene.

Non-syndromic cleft lip with or without cleft palate (nsCL/P) ranks among the most common human congenital malformations, and has a multifactorial background in which both exogenous and genetic risk factors act in concert. The present report describes a genome-wide association study (GWAS) involving a total of 285 nsCL/P patients and 1212 controls from the Netherlands and Belgium. Twenty of the 40 previously reported nsC/LP susceptibility loci were replicated, which underlined the validity of this sample. SNV-based analysis of the data identified an as yet unreported suggestive locus at chromosome 16p12.1 (p-value of the lead SNV: 4.17 × 10-7). This association was replicated in two of three patient/control replication series (Central European and Yemeni). Gene analysis of the GWAS data prioritized SH3PXD2A at chromosome 10q24.33 as a candidate gene for nsCL/P. To date, support for this gene as a cleft gene has been restricted to data from zebrafish and a knockout mouse model. The present GWAS was the first to implicate SH3PXD2A in non-syndromic cleft formation in humans. In summary, although performed in a relatively small sample, the present GWAS generated novel insights into nsCL/P etiology.

Level of agreement on postoperative complications after one-stage hypospadias correction comparing medical records and parent reports.

PURPOSE: To analyze agreement on postoperative complications after hypospadias surgery according to medical records and parents' reports. MATERIALS & METHODS: In this retrospective cohort study, data were collected from 409 children who received an initial one-stage hypospadias correction in the Radboudumc, The Netherlands. Postoperative complications according to medical records were compared with parent-reported complications in an online questionnaire. Main complications studied were wound-related complications, urinary tract infections, fistulas, stenosis, and prepuce-related complications. Agreement was determined by Cohen's kappa coefficient. RESULTS: Slightly less complications were mentioned in medical records (37%) compared to parents' reports (42%). Overall agreement was moderate (κ = 0.50, 95% confidence interval (CI):0.41-0.59), but poor for some specific complications. Agreement was higher for complications that needed reoperation compared to when no reoperation was performed (κ = 0.53, 95% CI: 0.43-0.62 and κ = 0.18, 95% CI: 0.06-0.31) and for patients with recent surgery (<5 years before questionnaire completion) compared to less recent surgeries (κ = 0.69, 95% CI: 0.55-0.84 and κ = 0.43, 95% CI: 0.33-0.54). CONCLUSIONS: Agreement on complications according to medical records and parents' reports was poor to moderate, but better after reoperation and more recent surgery. Some complications mentioned in medical records were missing from parents' reports and the other way around. Better agreement will give physicians and parents a more reliable view on postoperative outcome after hypospadias surgery. TYPE OF STUDY: Diagnostic test. LEVEL OF EVIDENCE: Level III.

Congenital diaphragmatic hernia is associated with nonscrotal testes.

BACKGROUND: Congenital diaphragmatic hernia (CDH) is a rare birth defect with a high mortality and morbidity. Nonscrotal testes (NST) are the most reported genital anomaly in boys. Both defects have known associated anomalies, but little is known about the association between CDH and NST. This study evaluates this association and the location of the NST in a large cohort of male CDH survivors. Moreover, we analyzed possible associative factors for NST in CDH patients. METHODS: A cohort of CDH patients, born between January 2000 and March 2014 and treated in a high volume expertise center, was evaluated retrospectively. Boys with a minimum follow-up of 18months were included. The patients were evaluated for testes location, performed orchidopexy, and possible associative factors such as birth weight, gestational age, other congenital anomalies and CDH characteristics (surgical treatment, approach and ECMO). RESULTS: Seventy-five CDH patients were included. Twenty-seven (36%) were diagnosed with NST, of which 22 (29%) received orchidopexy. In 54 patients (72%) there were reports on testes location at birth and location was known for all patients at the age of 18months, although side of NST was unknown in four. The location of the NST was mostly ipsilateral to the CDH (n=20, 87%), of which eight (35%) had a bilateral NST with a unilateral CDH. There were no significant differences in birth weight, gestational age, and CDH specific characteristics in patients with or without NST. CONCLUSION: This study shows a strong association between CDH and NST, with a prevalence of 36%. However, no specific characteristics of the CDH were related to the NST. The testes of all male CDH patients should be thoroughly evaluated in the first year of their life, to ensure a proper and timely treatment. LEVEL OF EVIDENCE: Level IV; case series.

Factors related to long-term surgical morbidity in congenital diaphragmatic hernia survivors.

BACKGROUND: Patients born with a congenital diaphragmatic hernia (CDH) have a high mortality and morbidity. After discharge, complications and long-term morbidity are still encountered. This study describes the factors related to the surgical long-term outcomes in CDH survivors. METHODS: A cohort of CDH patients born between 2000 and 2014, with a minimum of two years follow up, were included in this retrospective study. Demographics, CDH specific characteristics, treatment, and long-term surgical outcome were evaluated using multivariate logistic regression analyses. RESULTS: 112 patients were included, with a mean follow up of 7.3 years (SD 3.8). The majority had primary repair, but 31% received patch repair. Recurrence was reported in 7% of all patients. However, recurrence risk increased for patients with extracorporeal membrane oxygenation (ECMO) treatment (ORadjusted: 6.3, 95% CI: 1.2-33.9). This risk was highest for patients needing both ECMO and patch repair (OR: 11.2, 95% CI: 2.3-54.1). Small bowel obstructions (SBO) were observed in 20% and was associated with patch repair (ORadjusted: 3.5, 95% CI: 1.2-10.0), but ECMO treatment seemed to reduce this risk (ORadjusted: 0.2, 95% CI: 0.0-1.0). Thoracic deformations (36%) was diagnosed most often after patch repair, especially when ECMO was needed (60%) as well. CONCLUSIONS: This retrospective study shows that the incidence of surgical long-term morbidity of CDH is relatively high, with different factors accounting for this. Diaphragmatic hernia recurrence was strongest associated with ECMO treatment in combination with patch repair, while SBO's were associated with patch repair, with an unexpected protective effect of ECMO treatment. TYPE OF STUDY: Retrospective comparative study - Level III evidence.

Bilateral congenital diaphragmatic hernia: prognostic evaluation of a large international cohort.

BACKGROUND: Congenital diaphragmatic hernia (CDH) is a lethal birth defect, which occurs in 1:2000-3000 live births. Bilateral CDH is a rare form (1%), with a high mortality. This study presents the outcomes of the largest cohort of bilateral CDH patients. METHODS: The records of patients with bilateral CDH from the Congenital Diaphragmatic Hernia Registry born between 1995 and 2015 were retrospectively analyzed to identify parameters associated with mortality. RESULTS: Eighty patients with a bilateral CDH were identified. Overall mortality was 74% (n=59). Apgar scores at 1 and 5min were statistically lower in the non-survivors compared to the survivors (median 3.0 and 5.0, versus 6.5 and 8.0, respectively, p<0.001). All survivors were repaired (n=21), compared to 22% of the non-survivors (n=17). The type of repair was equally divided in the survivors (52% primary versus 48% patch), while non-survivors were mainly patch repaired (82% versus 12%). Nineteen were treated with extracorporeal membrane oxygenation (ECMO) (24%), only three of them survived. When calculating the risk on mortality for the patients who lived until repair, ECMO had an adjusted odds ratio for mortality of 10.8 (95% CI: 2.0-57.7) and patch repair 5.2 (95% CI: 0.8-34.9). CONCLUSIONS: The treatment of bilateral CDH patients remains challenging with a high mortality rate. Lower Apgar-scores, ECMO (probably as a surrogate for the severity of disease), and patch repair were negatively associated with outcome. LEVEL OF EVIDENCE: Level IV study.