Teaching hypospadias repair by utilising a novel 3D-printed silicon model: An initial assessment using structured trainee and trainer feedback.

INTRODUCTION: Simulated paediatric surgical training is inherently advantageous and flourishing. Moreover, several working conditions resulted in reduced training hours, index and subspecialty cases encountered, and the COVID-19 pandemic affected elective surgery backlogs, hence training opportunities. Hypospadias repair is technically-demanding and requires a spectrum of dissective and reconstructive skills. We therefore aimed to test a 3D-printed silicon model for hypospadias repair, in the context of hands-on surgical training. MATERIAL AND METHODS: Twenty-Seven trainees, under the supervision of 15 instructors, completed the activity. They were given a seminar to show the relevant anatomy, and 8 key steps of the exercise: (1)-degloving; (2)-urethral plate marking; (3)-incision; (4)-tubularisation; (5)-glansplasty/glanuloplasty; (6)-dartos layer preparation; (7)-preputioplasty and (8)-skin closure. Each trainee completed a structured feedback assessment. An on-site trainer supervised and evaluated each exercise. Trainees and trainers rated the model through the above steps from unsatisfactory-(1/5) to excellent-(5/5), presented herein via cross-sectional analysis. RESULTS: Eleven-(40.7 %) trainees were in years:1-3 of specialist training, 10-(37 %) were in years:4-6, and 6-(22.2 %) were beyond year-6. Two-(7.4 %) trainees had nil-hypospadias experience, 16-(59.2 %) previously assisted in procedures or performed steps, 5-(18.5 %) performed whole procedures supervised and 4-(14.8 %) independently. Twenty-(74 %) trainees and 15-(100 %) instructors judged the model to resemble the anomaly. Seventeen-(63 %) trainees and 13-(86.6 %) instructors rated the material needle-penetrability ≥3/5, compared to human tissue. Sixteen-(59 %) trainees and 13-(86.6 %) instructors rated the material suture holding ≥3/5. Eleven-(73.3 %) trainees and 13-(86.6 %) instructors rated sutures' evenness and edge coaptability ≥3/5. DISCUSSION: Hypospadias is an index operation, which requires precision skills. Simulated training in Paediatric Surgery and Urology is gaining importance. 3D-printed models are gaining a key role in simulated training. The study presents a novel 3D-printed high-fidelity silicon-based hypospadias model designed for hands-on training. A structured pathway to divide a standard hypospadias repair into key steps is displayed to ensure skill acquisition and stabilisation. CONCLUSION: This 3D-printed silicon-based hypospadias model is proven useful for hands-on training. The fidelity can still improve, especially regarding suture holding of the material. LEVEL OF EVIDENCE: LEVEL III.

Association between genetic variations in carbamoyl-phosphate synthetase gene and persistent neonatal pulmonary hypertension.

Persistent pulmonary hypertension of the new-borns (PPHN) is one of the main etiologies of morbidity as well as mortality in neonates. Previous studies found that genetic polymorphisms in urea cycle enzymes are associated with PPHN. Few of the genetic polymorphisms in neonates have been recognized with PPHN. We aimed to find out the prevalence of the CPS-I gene polymorphism and to correlate the genotype with the serum nitric oxide (NO) levels in Egyptian neonates with idiopathic PPHN. We included neonates diagnosed with PPH (n = 150) while the control group included healthy neonates with matched age and sex (n = 100). The CPS-I gene polymorphism: A/C, trans-version substitution, rs4399666 genotype was identified using TaqMan-based quantitative PCR. The results revealed that the CPS-I A/C rs4399666 gene polymorphism and lower serum NO levels were significantly associated with idiopathic PPHN in neonates. In addition, serum NO level was significantly associated with an rs4366999 A/C variant gene in idiopathic PPHN (p = 0.001). Univariable regression analysis demonstrated that there was a significant association between CPS-I A/C rs4399666 CC and increased risk of PPHN (odd ratio, 95% CI of 1.8 (0.78 to 1.75), p-value = 0.04).Conclusion: We concluded that mutant CPS-I A/C rs4399666 minor variant especially the homozygous CC genotype is frequently distributed among the PPHN group. This demonstrates that the presence of mutant CPS-I rs4399666 does not necessarily predispose to the development of PPHN in neonates, but nonetheless, if the C allele is inherited in the homozygous CC genotype, it is associated with a higher risk of PPHN. What is Known: • Prior studies found that polymorphisms in urea cycle enzyme genes are associated with PPHN. • Association between CPS-1 gene polymorphisms is significantly associated with PPHN. What is New: • The prevalence of CPS-1, A/C trans-version substitution, rs4399666 gene polymorphism in Egyptian neonates presented with idiopathic PPHN. • Mutant CPS-I A/C rs4399666 especially the homozygous CC genotype is more frequently distributed among PPHN, and it is significantly associated with low serum nitric oxide level.

Gentamicin extended interval regimen and ototoxicity in neonates.

OBJECTIVES: To assess the extended interval regimen gentamicin associated ototoxicity in neonatal intensive care unit using hearing tests. METHODS: Two hundred and twenty neonates admitted to neonatal intensive care were assessed; 110 neonates who had received gentamicin and 110 neonates who had not received gentamicin served as control group. Gentamicin group were further subdivided according to the duration of treatment into 50 neonates who had received gentamicin for 5 days or less and 60 neonates who had received gentamicin for more than 5 days. TEOAEs were used for hearing screening. Auditory brain response was performed 3 months later for failed cases to confirm the hearing impairment. RESULTS: Three neonates failed TEOAEs screening in each group but hearing impairment was confirmed in one neonate only (0.9%) in each group (gentamicin and control groups). Neonates who received gentamicin for more than 5 days showed comparable results as regard TEOAEs or ABR results with those who received gentamicin for 5 days or less, and control group. CONCLUSIONS: Extended interval dosing of gentamicin therapy in neonates does not increase the incidence of hearing loss. This suggests that hearing loss in neonatal intensive care unit may be attributed to factors other than gentamicin treatment.

Enteric viral infections as potential risk factors for intussusception.

INTRODUCTION: We aimed to identify potential risk factors for intussusception (ISS) among children presenting to two pediatric hospitals in Egypt. METHODOLOGY: In this case-control study,  enrolled children < 3 years old with ISS (confirmed radiologically and/or surgically) were  matched by age and gender to controls admitted with acute non-abdominal surgical illnesses. Stool samples were collected and tested for various enteric bacteria, rotavirus, enteric adenoviruses (EA, 40 and 41) and astroviruses using commercially available ELISA diagnostic kits. RESULTS: From December 2004 to May 2009, 158 cases and 425 matched controls were enrolled. A history of diarrhoea and cough over the preceding four weeks of interview were more common in cases than controls, respectively. Children with mothers who had secondary education and above were 2.2 times more likely to have ISS than those whose mothers had a lower level of education. In spite of the low detection rate of EA infection (regardless of diarrhoea history) and asymptomatic rotavirus infection, they were detected in higher frequencies in cases than controls; however, infection with astrovirus and bacterial pathogens did not appear to be associated with increased risk of ISS. CONCLUSIONS: History of diarrhoea and cough over the four weeks preceding the study and maternal education above secondary level were potential risk factors for ISS. EA and asymptomatic rotavirus infection were detected in higher frequencies among cases than controls; however, association with ISS cannot be confirmed. Additional research is needed to confirm these findings and evaluate the pathogenesis which may link such infections with ISS.

Immune-mediated liver injury: prognostic value of CD4+, CD8+, and CD68+ in infants with extrahepatic biliary atresia.

BACKGROUND: Hepatic fibrosis and cirrhosis develop progressively in extrahepatic biliary atresia (EHBA) despite timely surgical intervention. PURPOSE: The aim of the study was to define CD4+ helper T lymphocytes, cytotoxic CD8+ T lymphocytes, and CD68+ (macrophages) infiltration of portal tracts and lobules and hepatic fibrosis as possible predictive measures of outcome of infants having EHBA. METHODS: The outcome of 32 infants with EHBA was correlated to their percutaneous biopsy and postportoenterostomy core liver tissue infiltration by CD4+, CD68+, and CD8+ cells and to the degree of detected fibrosis. RESULTS: Portoenterostomy cores were heavily infiltrated by CD4+, CD8+, and CD68+, compared with the preoperative liver biopsy (P = .008, .004, and .017, respectively). Infants having favorable outcome had more macrophage infiltration in portoenterostomy core compared with those having an unfavorable outcome (25.66 +/- 29.77 per HPF compared with 11.62 +/- 4.58, P = .000). Mean CD4+/CD8+ ratio was 1.54 +/- 1.37 in those who died within 18 months postoperatively and 0.733 +/- 0.48 in others (P = .021). CONCLUSION: Immune-mediated destruction of portal tracts is an integral part of pathogenesis of EHBA.

Evaluation of renal glomerular and tubular functional and structural integrity in neonates.

BACKGROUND: Renal cells are not fully differentiated at birth, representing a major risk in preterm infants. We evaluated glomerular and tubular functional integrity as well as structural integrity of renal tubules among healthy full-term and preterm infants as well as diseased preterm infants. METHODS: A total of 50 newborns (10 healthy full-term, 10 healthy preterm, and 30 diseased preterm, at 38.9 +/- 1.10, 34.2 +/- 0.92, and 32 +/- 2.47 weeks gestational age, respectively) were included in the present study. Glomerular function was assessed by measuring urinary levels of both microalbumin and immunoglobulin G as well as serum creatinine levels, whereas the proximal tubular function was investigated by measuring the urinary levels of both alpha1-microglobulin and beta2-microglobulin as well as retinol-binding protein. Also, distal tubular reabsorption capacity was investigated by assessing fractional excretion of sodium. Moreover, the structural integrity of renal proximal tubules was studied by measuring the urinary activities of both the brush-border membrane enzyme leucine-aminopeptidase (LAP) and the lysosomal enzyme N-acetyl-beta-D-glucosaminidase. The preceding investigations were done on both the first and third days of life of all 50 newborns. RESULTS: Glomerular and tubular function and structure was relatively impaired at birth among both healthy and diseased preterm as well as healthy full-term neonates and improved rapidly thereafter. The diseased preterm neonates showed worse renal function and structure with minimal improvement regardless of the underlying sickness. CONCLUSION: Renal insufficiency and renal immaturity could be evaluated using enzymuria and low- and high-molecular-weight proteinuria as noninvasive methods.