The contribution of associated congenital anomalies in understanding Hirschsprung's disease

Delayed diagnosis in Hirschsprung disease

INTRODUCTION

Diagnostic delay in Hirschsprung disease is uncommon. Different definitions have been proposed but that of a diagnosis achieved after 12 months of age seems to be the most reliable and resorted to. Some authors reported a worse outcome in case of delay. Our study aims at providing the most relevant features of a series of patients who received a delayed diagnosis of Hirschsprung disease.

MATERIALS AND METHODS

All consecutive patients admitted to our Center with a delayed diagnosis of Hirschsprung diseases between January 2017 and July 2023 have been retrospectively enrolled. Demographic data, phenotype, genotype, surgical complications, and outcome were assessed and compared to those of literature. A number of variables were also compared to those of a series of patients admitted during the same study period without a delayed diagnosis.

RESULTS

A total of 45 patients were included (16.4% out of a series of 346 patients with data regarding age at diagnosis). Male to female ratio was 3.1:1. Median age at diagnosis was 41 months with a wide variation (range between 17 months and 58 years). All patients but 2 suffered from classic rectosigmoid aganglionosis. Normal meconium passage (58%) was reported in a significantly higher number of patients compared to what observed in a series without diagnostic delay (p = 0.0140). All other variables (associated anomalies, preoperative enterocolitis, complications, and functional outcome) proved not to have statistically significant differences compared to a series of patients without a diagnostic delay.

CONCLUSIONS

The results of our study underline that a significant percentage of patients are basically missed in the neonatal period mostly due to mild symptoms. Overall outcome does not differ from that of patients without diagnostic delay. Nonetheless, we underline the importance of a throughout investigation of all patients with meconium delay/failure and that of adopting a low threshold for performing rectal suction biopsies in constipated children to avoid misdiagnosis to serve the best for our patients.

Short and Long-Term Outcomes in Hirschsprung Disease: Are the Syndrome-Associated Patients Really Doing Worse?

INTRODUCTION

Given the lack of data to help caregivers in the follow-up of Hirschsprung disease (HD), this study aimed to compare the functional outcomes of isolated Hirschsprung disease (I-HD) to syndrome-associated Hirschsprung disease (SA-HD) at 1, 3, 5, and 10 years.

METHODS

A retrospective chart review of patients diagnosed with HD between January 1990 and May 2021 at our pediatric center was performed to collect data on patient characteristics, investigations, and treatments. Ninety-five patients were identified, of whom 76 were included in the study. SA-HD is defined as a syndrome known to be associated with HD or cognitive impairment.

RESULTS

Patient characteristics were comparable between groups ( P > 0.05). There were 52 patients with I-HD and 24 with SA-HD. The patients median age was 9 days at diagnosis and 1.5 month at surgery. SA-HD patients became bowel continent at a significantly older age (mean age 8.43 vs 4.94 years, P = 0.0471) and received more bowel continence medications. At 5 years, SA-HD patients requiring ≥2 medications for bowel continence represented 54.5% versus 11.1% of I-HD patients ( P = 0.009). Lastly, SA-HD patients had urinary incontinence at a significantly older age ( P = 0.0136, 5 years).

CONCLUSION

Clinicians should be aware that SA-HD patients are more prone to bladder dysfunction and became bowel continent at an older age than I-HD patients. They need more and prolonged bowel management medications, and other important complications need to be addressed in patient care. These results should prompt a longer follow-up period for these patients, especially in SA-HD.

Hirschsprung disease

Hirschsprung disease (HSCR) is a rare congenital intestinal disease that occurs in 1 in 5,000 live births. HSCR is characterized by the absence of ganglion cells in the myenteric and submucosal plexuses of the intestine. Most patients present during the neonatal period with the first meconium passage delayed beyond 24 h, abdominal distension and vomiting. Syndromes associated with HSCR include trisomy 21, Mowat-Wilson syndrome, congenital central hypoventilation syndrome, Shah-Waardenburg syndrome and cartilage-hair hypoplasia. Multiple putative genes are involved in familial and isolated HSCR, of which the most common are the RET proto-oncogene and EDNRB. Diagnosis consists of visualization of a transition zone on contrast enema and confirmation via rectal biopsy. HSCR is typically managed by surgical removal of the aganglionic bowel and reconstruction of the intestinal tract by connecting the normally innervated bowel down to the anus while preserving normal sphincter function. Several procedures, namely Swenson, Soave and Duhamel procedures, can be undertaken and may include a laparoscopically assisted approach. Short-term and long-term comorbidities include persistent obstructive symptoms, enterocolitis and soiling. Continued research and innovation to better understand disease mechanisms holds promise for developing novel techniques for diagnosis and therapy, and improving outcomes in patients.

Hospital Length of Stay and Surgery among European Children with Rare Structural Congenital Anomalies-A Population-Based Data Linkage Study

Little is known about morbidity for children with rare structural congenital anomalies. This European, population-based data-linkage cohort study analysed data on hospitalisations and surgical procedures for 5948 children born 1995-2014 with 18 rare structural congenital anomalies from nine EUROCAT registries in five countries. In the first year of life, the median length of stay (LOS) ranged from 3.5 days (anotia) to 53.8 days (atresia of bile ducts). Generally, children with gastrointestinal anomalies, bladder anomalies and Prune-Belly had the longest LOS. At ages 1-4, the median LOS per year was ≤3 days for most anomalies. The proportion of children having surgery before age 5 years ranged from 40% to 100%. The median number of surgical procedures for those under 5 years was two or more for 14 of the 18 anomalies and the highest for children with Prune-Belly at 7.4 (95% CI 2.5-12.3). The median age at first surgery for children with atresia of bile ducts was 8.4 weeks (95% CI 7.6-9.2) which is older than international recommendations. Results from the subset of registries with data up to 10 years of age showed that the need for hospitalisations and surgery continued. The burden of disease in early childhood is high for children with rare structural congenital anomalies.

Sexual function and lower urinary tract symptoms after minimally invasive endorectal pull-through in adolescent males with Hirschsprung disease

BACKGROUND

Effects of colorectal resection on sexual function and the lower urinary tract are inadequately studied in patients with Hirschsprung disease (HD). This study aimed to increase existing knowledge on sexual function and lower urinary tract symptoms (LUTS) in HD male adolescents operated with minimally invasive endorectal pull-through (ERPT).

METHODS

Non-syndromic male adolescents (12-18 years) operated with ERPT were invited to participate in this single-center cross-sectional study which included a semi-structured interview on sexual function and LUTS, a questionnaire recording LUTS, and a urodynamic study. Uroflowmetry curves were eligible for evaluation if the voided volume was >50% of expected bladder capacity. Ethical approval and informed consent were obtained.

RESULTS

Of 37 eligible male adolescents, 35 (95%) with a median age of 14.9 (12.0 -18.3) years were included. 94% had rectosigmoid aganglionosis, and 97% underwent a minimally invasive ERPT. 34 (97%) visited the outpatient clinic. The ability to get erections and to ejaculate was assessed in 25/35 (71%) adolescents. 25/25 (100%) could get an erection, and of adolescents ≥15 years 14/15 (93%) could ejaculate. 32 (91%) returned the questionnaire and underwent urodynamic studies. 15/32 (47%) reported LUTS, but most had only sporadic LUTS. 31/32 (97%) were highly satisfied with their bladder function. Sporadic urinary incontinence was reported by 4/32 (13%), but none reported social problems due to this. Of the eligible 28/32 (88%) uroflowmetry curves, 15/28 (54%) were normal.

CONCLUSIONS

Minimally invasive ERPT seems to preserve sexual function and does not induce lower urinary tract symptoms in adolescent HD males.

LEVEL OF EVIDENCE

III.

Congenital cysts of the lower male genitourinary tract: a disorder with various treatment approaches and pitfalls-case report

BACKGROUND

The cysts of the male pelvic floor represent a rare clinical entity. Their origin is linked to an altered development of paramesonephric and mesonephric ducts during embryogenesis.

CASE PRESENTATION

We report our experience regarding two patients presenting cysts of the ejaculatory system treated with open and mini-invasive surgery. The patients referred to our clinic with nonspecific symptoms and the diagnosis was obtained by radiological investigations. The patient treated with an open approach developed a pelvic purulent collection and a fistula of the prostatic urethra, managed with surgical drainage and prolonged bladder catheterization. On the other hand, the patient treated with laparoscopic approach did not develop any complications. No sexual or ejaculatory disorders were reported.

CONCLUSIONS

Patients with congenital cysts of the pelvic floor must be adequately informed about the risks and benefits of surgery and a careful counseling is mandatory before surgery. Treatment is recommended for symptomatic patients and an endoscopic approach is associated with a high rate of recurrence. A laparoscopic approach, when possible, is desirable.

Aberrant high expression of the TET1 gene in Hirschsprung's disease

BACKGROUND

The pathogenesis of Hirschsprung's disease (HSCR) remains unclear but might involve genes participating in neural crest development. Gene methylation controls the expression of many genes and is involved in the development and migration of neural crest cells, but the involvement of demethylation in HSCR is unknown. This study aimed to investigate the expression of ten-eleven translocation methylcytosine dioxygenase 1 (TET1) (a demethylation protein) in patients with HSCR.

METHODS

This is a retrospective study of surgical specimens from paediatric patients with and without HSCR (e.g., intussusception and incarcerated hernia) obtained from 07/2015 to 08/2017. TET1 expression was determined by qRT-PCR, western blotting, and immunohistochemistry. The levels of 5-hydroxymethylcytosine were determined by the dot blot assay.

RESULTS

The specimens of 35 patients with HSCR and 25 controls were collected. The median TET1 mRNA expression values were 1.028 [HSCR-stenotic (S)], 0.908 [HSCR-dilated (D)], and 0.467 (control) (HSCR-S vs. control: P = 0.002; HSCR-D vs. control: P = 0.008; HSCR-S vs. HSCR-D: P = 0.44). TET1 protein levels followed a similar pattern. The intensity of immunostaining identified higher expression of TET1 in HSCR colon tissues compared with control tissues. The 5-hmC levels in HSCR stenotic segment samples were significantly higher than those in controls.

CONCLUSION

The expression of TET1 is higher in paediatric patients with HSCR than in controls. DNA demethylation initiated by TET1 may be related to HSCR, which demonstrates that TET1 may play a role in the development of HSCR.

What parents need to know about Hirschsprung disease

Hirschsprung's disease (HD) is a complex colorectal disorder that can be challenging to understand and overwhelming to many parents. Counseling parents is critical for ensuring they understand their child's condition, how it must be treated, pitfalls that can occur during treatment, and how they will do in the long term. This article breaks down this process into a series of informally worded questions and reviews evidence-based discussion points around the most common concerns parents will have: survival, pathophysiology, surgical correction and complications, etiology and genetic basis, associated issues, outcomes, and familial nature. Where evidence is unclear, expert opinion is included. Discussion is geared towards the parents of a newly diagnosed and otherwise healthy neonate, with a brief section on complex situations including associated syndromes and late diagnosis. Embarking on the longitudinal care of a child with HD is a complex undertaking and requires significant parental education to establish a proper parent-surgeon relationship, an essential factor for optimizing outcome and family satisfaction.

Disparate phenotypes in two unfavorable pregnancies due to maternal mosaicism of a novel RET gene mutation

Mutations in RET have been found in multiple diseases including isolated and associated congenital anomalies. Here, we report a case presented with disparate phenotypes in each pregnancy but caused by the same novel mutation. Whole-exome sequencing (WES) was performed on the proband/abortion product-parental trio and a novel missense variant in RET (chr10:43615610C>G; c.2689C>G; p.Arg897Gly) was identified. The mother was a low-level somatic carrier of this new mutation, with 17.3% in blood, 19.1% in oralmucous membrane, and 15.7% in urine by droplet digital polymerase chain reaction (dd PCR). Our finding not only broadens the mutation spectrum of RET but also gives supportive genetic counseling and timely guidance on fertility choices.

Gastrointestinal Emergency in Neonates and Infants: A Pictorial Essay

Gastrointestinal (GI) emergencies in neonates and infants encompass from the beginning to the end of the GI tract. Both congenital and acquired conditions can cause various GI emergencies in neonates and infants. Given the overlapping or nonspecific clinical findings of many different neonatal and infantile GI emergencies and the unique characteristics of this age group, appropriate imaging is key to accurate and timely diagnosis while avoiding unnecessary radiation hazard and medical costs. In this paper, we discuss the radiological findings of essential neonatal and infantile GI emergencies, including esophageal atresia and tracheoesophageal fistula, hypertrophic pyloric stenosis, duodenal atresia, malrotation, midgut volvulus for upper GI emergencies, and jejunoileal atresia, meconium ileus, meconium plug syndrome, meconium peritonitis, Hirschsprung disease, anorectal malformation, necrotizing enterocolitis, and intussusception for lower GI emergencies.

E-liquids and vanillin flavoring disrupts retinoic acid signaling and causes craniofacial defects in Xenopus embryos

Environmental teratogens such as smoking are known risk factors for developmental disorders such as cleft palate. While smoking rates have declined, a new type of smoking, called vaping is on the rise. Vaping is the use of e-cigarettes to vaporize and inhale an e-liquid containing nicotine and food-like flavors. There is the potential that, like smoking, vaping could also pose a danger to the developing human. Rather than waiting for epidemiological and mammalian studies, we have turned to an aquatic developmental model, Xenopus laevis, to more quickly assess whether e-liquids contain teratogens that could lead to craniofacial malformations. Xenopus, like zebrafish, has the benefit of being a well-established developmental model and has also been effective in predicting whether a chemical could be a teratogen. We have determined that embryonic exposure to dessert flavored e-liquids can cause craniofacial abnormalities, including an orofacial cleft in Xenopus. To better understand the underlying mechanisms contributing to these defects, transcriptomic analysis of the facial tissues of embryos exposed to a representative dessert flavored e-liquid vapor extract was performed. Analysis of differentially expressed genes in these embryos revealed several genes associated with retinoic acid metabolism or the signaling pathway. Consistently, retinoic acid receptor inhibition phenocopied the craniofacial defects as those embryos exposed to the vapor extract of the e-liquid. Such malformations also correlated with a group of common differentially expressed genes, two of which are associated with midface birth defects in humans. Further, e-liquid exposure sensitized embryos to forming craniofacial malformations when they already had depressed retinoic acid signaling. Moreover, 13-cis-retinoic acid treatment could significantly reduce the e-liquid induced malformation in the midface. Such results suggest the possibility of an interaction between retinoic acid signaling and e-liquid exposure. One of the most popular and concentrated flavoring chemicals in dessert flavored e-liquids is vanillin. Xenopus embryos exposed to this chemical closely resembled embryos exposed to dessert-like e-liquids and a retinoic acid receptor antagonist. In summary, we determined that e-liquid chemicals, in particular vanillin, can cause craniofacial defects potentially by dysregulating retinoic acid signaling. This work warrants the evaluation of vanillin and other such flavoring additives in e-liquids on mammalian development.

Congenital anomalies of the kidney and urinary tract in a cohort of 280 consecutive patients with Hirschsprung disease

BACKGROUND

Congenital anomalies of the kidney and urinary tract (CAKUT) have been underestimated in Hirschsprung disease (HSCR). This paper aims at reporting results of patients with HSCR who underwent kidney and urinary tract assessment.

METHODS

Patients seen between December 2005 and November 2020 underwent a complete kidney and urinary tract diagnostic workup. Data regarding CAKUT, gender, length of aganglionosis, familial history, HSCR-associated enterocolitis (HAEC), RET genotype, and outcome were collected.

RESULTS

Out of 472 patients, 280 completed the workup and represented the focus. Male to female ratio was 3.24:1. Familial cases accounted for 9.8% of patients. RET mutations were detected in 19.8%. We encountered a total of 61 patients with 70 nephrological issues (21.8%), including 28 hypoplasia/dysplasia, 12 hydronephrosis, 11 vesicoureteric reflux, 7 duplex collecting system, 2 kidney agenesis, 2 horseshoe kidney, and 8 miscellanea, involving 91 kidneys without side preponderance (50 right, 41 left). Of these 61 patients, 20 (7.1% of the whole series) required medical or surgical treatment. When comparing patients with and without CAKUT, familial history proved to occur with a significantly lower frequency in the former as did better patient perspectives of outcome.

CONCLUSIONS

We confirmed that all diagnostic workups in HSCR should include a complete kidney and urinary tract diagnostic workup. Our study suggests that genes other than RET could play a role in determining CAKUT. Given worse patient perspectives of outcome, CAKUT seems to significantly interfere with quality of life thus confirming the need for early diagnosis and tailored prevention strategies.

Loss-of-function mutation of c-Ret causes cerebellar hypoplasia in mice with Hirschsprung disease and Down's syndrome

The c-RET proto-oncogene encodes a receptor-tyrosine kinase. Loss-of-function mutations of RET have been shown to be associated with Hirschsprung disease and Down's syndrome (HSCR-DS) in humans. DS is known to involve cerebellar hypoplasia, which is characterized by reduced cerebellar size. Despite the fact that c-Ret has been shown to be associated with HSCR-DS in humans and to be expressed in Purkinje cells (PCs) in experimental animals, there is limited information about the role of activity of c-Ret/c-RET kinase in cerebellar hypoplasia. We found that a loss-of-function mutation of c-Ret Y1062 in PCs causes cerebellar hypoplasia in c-Ret mutant mice. Wild-type mice had increased phosphorylation of c-Ret in PCs during postnatal development, while c-Ret mutant mice had postnatal hypoplasia of the cerebellum with immature neurite outgrowth in PCs and granule cells (GCs). c-Ret mutant mice also showed decreased numbers of glial fibers and mitogenic sonic hedgehog (Shh)-positive vesicles in the external germinal layer of PCs. c-Ret-mediated cerebellar hypoplasia was rescued by subcutaneous injection of a smoothened agonist (SAG) as well as by reduced expression of Patched1, a negative regulator for Shh. Our results suggest that the loss-of-function mutation of c-Ret Y1062 results in the development of cerebellar hypoplasia via impairment of the Shh-mediated development of GCs and glial fibers in mice with HSCR-DS.

Hirschsprung's Disease-Recent Understanding of Embryonic Aspects, Etiopathogenesis and Future Treatment Avenues

Hirschsprung's disease is a neurocristopathy, caused by defective migration, proliferation, differentiation and survival of neural crest cells, leading to gut aganglionosis. It usually manifests rapidly after birth, affecting 1 in 5000 live births around the globe. In recent decades, there has been a significant improvement in the understanding of its genetics and the association with other congenital anomalies, which share the pathomechanism of improper development of the neural crest. Apart from that, several cell populations which do not originate from the neural crest, but contribute to the development of Hirschsprung's disease, have also been described, namely mast cells and interstitial cells of Cajal. From the diagnostic perspective, researchers also focused on "Variants of Hirschsprung's disease", which can mimic the clinical signs of the disease, but are in fact different entities, with distinct prognosis and treatment approaches. The treatment of Hirschsprung's disease is usually surgical resection of the aganglionic part of the intestine, however, as many as 30-50% of patients experience persisting symptoms. Considering this fact, this review article also outlines future hopes and perspectives in Hirschsprung's disease management, which has the potential to benefit from the advancements in the fields of cell-based therapy and tissue engineering.

Total colonic aganglionosis and cleft palate in a newborn with Janus-cysteine 618 mutation of RET proto-oncogene: a case report

Background

Hirschsprung disease, the most important congenital colonic dysmotility in children results from neural crest migration, differentiation, proliferation, or apoptosis defects where the rearranged during transfection (RET)-Protooncogene pathway has a central role. Although palatal and retinal anomalies in the context of chromosomopathies and some mono−/oligogenic syndromes are reported associated with Hirschsprung disease the role of inactivating RET mutations in these cases is not clarified.

Case presentation

We report on a dysmorphic newborn with cleft palate and palatal synechia, who showed intestinal obstruction after 24 h of life. Transient ileostomy and surgical biopsies were performed to diagnose aganglionosis of the colon and last ileal loop. No chromosomal anomalies or copy number variations were found. We identified a paternal heterozygous germline mutation c.1852 T > C, which results in the substitution of cysteine by arginine in the RET-receptor tyrosine kinase (p.C618R mutation). There was no family history of Hirschsprung disease, but the father underwent surgery for medullary thyroid carcinoma and was affected by retinal dystrophy.

Conclusions

The occurrence of Hirschsprung disease and carcinoma shows how a single mutation may be responsible for adverse effects: gain and loss of function of the same receptor. Furthermore, it would be interesting to study its dual role in face and retina embryology, and to extend targeted investigations of RET hotspots in these developmental abnormalities to facilitate counselling, follow-up, and tumor prevention. Complex surgical procedures and genetic testing as well as socio-economic impact are a challenge for familiar compliance.

Hirschsprung's Disease in the Preterm Infant: Implications for Diagnosis and Outcome

Hirschsprung's disease (HD), congenital absence of ganglion cells, is considered uncommon in preterm infants. The aim was to describe the frequency, presentation, and surgical outcomes of preterm infants with HD. A retrospective cohort study was conducted of all patients diagnosed with HD from 2002 to 2012 at a single children's hospital. Clinical presentation and surgical outcomes were obtained for term (37 weeks of gestation or greater) and preterm infants. One hundred twenty-nine subjects with HD were identified, 24 (19%) preterm and 105 (81%) term. Preterm infants were more likely to be diagnosed after 30 days of life (66.7 vs 37.1%, P < 0.01; median age 2.9 vs 0.3 months, P < 0.05) and to have associated major congenital anomalies (45.8 vs 20.0%, P < 0.01). Fewer preterm infants had primary pull-through operations (45.8 vs 76.2%, P < 0.005). Preterm infants were more likely to have an episode of Hirschsprung's-associated enterocolitis (45.8 vs 24.0%, P < 0.05) but were not more likely to die from any cause (8.3 vs 5.8%, P = 0.64). HD may be more common in preterm infants than previously recognized, and increased comorbidities in these patients may lead to delayed diagnosis and increased morbidity. HD should be considered in the preterm infant presenting with a bowel obstruction, especially when accompanied by associated anomalies.

Genetic variants in RET, ARHGEF3 and CTNNAL1, and relevant interaction networks, contribute to the risk of Hirschsprung disease

Hirschsprung disease (HSCR), the most common enteric neuropathy, stands as a model for complex genetic disorders. It has recently been demonstrated that both ARHGEF3 and CTNNAL1 map to the RET-dependent HSCR susceptibility loci. We therefore sought to explore whether genetic variants within RET, ARHGEF3 and CTNNAL1, and their genetic interaction networks are associated with HSCR. Taking advantage of a strategy that combined the MassArray system and gene-gene interaction analysis with case-control study, we interrogated 38 polymorphisms within RET, ARHGEF3 and CTNNAL1 in 1015 subjects (502 HSCR cases and 513 controls) of Han Chinese origin. There were statistically significant associations between 20 genetic variants in these three genes and HSCR. Haplotype analysis also revealed some significant global P values, i.e. RET_ rs2435357-rs752978-rs74400468-rs2435353-rs2075913-rs17028-rs2435355 (P = 3.79×10^-58). Using the MDR and GeneMANIA platforms, we found strong genetic interactions among RET, ARHGEF3, and CTNNAL1 and our previously studied GAL, GAP43, NRSN1, PTCH1, GABRG2 and RELN genes. These results offer the first indication that genetic markers of RET, ARHGEF3 and CTNNAL1 and relevant genetic interaction networks confer the altered risk to HSCR in the Han Chinese population.

New mutations associated with Hirschsprung disease

INTRODUCTION

Hirschsprung Disease is caused by an impairment in cell migration from the neural crest to the gastrointestinal tract, resulting in an absence of neurons in the myenteric plexus. Many mutations in several genes have been associated to Hirschsprung disease; most of them affecting the RET proto-oncogen pathway. The purpose of this study is the description of novel and known mutations in genes associated to Hirschsprung disease and their prognostic implications.

MATERIAL AND METHODS

Retrospective analysis of patients with Hirschsprung disease and positive genetic studies evaluated from 1970 to 2013.

RESULTS

We found 21 positive genetic studies in the global series, 17 of them involving the RET proto-oncogene: Two of the mutations are novel and they have not been reported in the medical literature.

CONCLUSIONS

The RET protooncogene is the main gene associated with Hirschsprung disease. There are still multiple unknown mutations related to the pathogenesis of the disease. The study of this gene must be part of the work-up of all patients with Hirschsprung disease, as well as their first degree relatives if the mutation is associated with MEN2A and MEN2B syndromes.

[New mutations associated with Hirschsprung disease]

INTRODUCTION

Hirschsprung disease is caused by an impairment in cell migration from the neural crest to the gastrointestinal tract, resulting in an absence of neurons in the myenteric plexus. Many mutations in several genes have been associated to Hirschsprung disease; most of them affecting the RET proto-oncogen pathway. The purpose of this study is the description of novel and known mutations in genes associated to Hirschsprung disease and their prognostic implications.

MATERIAL AND METHODS

Retrospective analysis of patients with Hirschsprung disease and positive genetic studies evaluated from 1970 to 2013.

RESULTS

We found 21 positive genetic studies in the global series, 17 of them involving the RET proto-oncogene. Two of the mutations are novel and they have not been reported in the medical literature.

CONCLUSIONS

The RET protooncogene is the main gene associated with Hirschsprung disease. There are still multiple unknown mutations related to the pathogenesis of the disease. The study of this gene must be part of the work-up of all patients with Hirschsprung disease, as well as their first degree relatives if the mutation is associated with MEN2A and MEN2B syndromes.

ASSOCIATION OF RS2435357 AND RS1800858 POLYMORPHISMS IN RET PROTO-ONCOGENE WITH HIRSCHSPRUNG DISEASE: SYSTEMATIC REVIEW AND META-ANALYSIS

Introduction:

Many published studies have estimated the association of rs2435357 and rs1800858 polymorphisms in the proto-oncogene rearranged during transfection (RET) gene with Hirschsprung disease (HSCR) risk. However, the results remain inconsistent and controversial.

Aim:

To perform a meta-analysis get a more accurate estimation of the association of rs2435357 and rs1800858 polymorphisms in the RET proto-oncogene with HSCR risk.

Methods:

The eligible literatures were searched by PubMed, Google Scholar, EMBASE, and Chinese National Knowledge Infrastructure (CNKI) up to June 30, 2018. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the susceptibility to HSCR.

Results:

A total of 20 studies, including ten (1,136 cases 2,420 controls) for rs2435357 and ten (917 cases 1,159 controls) for rs1800858 were included. The overall results indicated that the rs2435357 (allele model: OR=0.230, 95% CI 0.178-0.298, p=0.001; homozygote model: OR=0.079, 95% CI 0.048-0.130, p=0.001; heterozygote model: OR=0.149, 95% CI 0.048-0.130, p=0.001; dominant model: OR=0.132, 95% CI 0.098-0.179, p=0.001; and recessive model: OR=0.239, 95% CI 0.161-0.353, p=0.001) and rs1800858 (allele model: OR=5.594, 95% CI 3.653-8.877, p=0.001; homozygote model: OR=8.453, 95% CI 3.783-18.890, p=0.001; dominant model: OR=3.469, 95% CI 1.881-6.396, p=0.001; and recessive model: OR=6.120, 95% CI 3.608-10.381, p=0.001) polymorphisms were associated with the increased risk of HSCR in overall.

Conclusions:

The results suggest that the rs2435357 and rs1800858 polymorphisms in the RET proto-oncogene might be associated with HSCR risk.

Urinary tract anomalies and urinary tract dysfunction in children with Hirschsprung disease-Is follow-up indicated?

BACKGROUND/PURPOSE

Urinary tract function in children with Hirschsprung disease (HD) is rarely considered.

AIM

to evaluate the prevalence of urinary tract anomalies and dysfunction in children with HD compared to controls.

METHODS

This was an observational cross sectional case-control study. Children with HD who underwent transanal endorectal pull-through technique (TERPT) from 2005 to 2017 were invited to participate. Ultrasound of the urinary tract was performed postoperatively. Children >4 years were asked to answer a urinary tract function questionnaire. Controls were age-matched healthy children. Ethical approval was obtained.

RESULTS

Seventy two children with HD and TERPT were included. Ultrasound was performed in 58 children (83%) post-TERPT. Ten anomalies were diagnosed in six children (10%). Structural anomalies included abnormal kidney size (7%), renal agenesis (2%), prominent calyces (2%) and renal pelvis anomaly (25). Probable acquired anomalies included hydronephrosis (2%), hydroureter (2%) and parenchymal damage (2%). One child had a prior nephrectomy owing to a Wilms' tumor. All 37 children >4 years (27 boys and 10 girls), median aged 8 years (range 4-12), answered the questionnaire as did 284 healthy controls (144 boys and 140 girls). Boys with HD reported a higher frequency of enuresis: 65% versus 9% (p = 0.001) and urinary tract infections: 18% versus 3% (p = 0.012). Girls with HD reported enuresis more frequently (60%) than healthy girls (7%) (p = 0.001). Children with HD with constipation reported enuresis more frequently (p = 0.038).

CONCLUSIONS

Urinary tract anomalies and dysfunction deserve attention in the follow-up of children with HD. We suggest screening for urinary tract anomalies and urinary tract symptoms in follow-up of children with HD.

TYPE OF STUDY

Treatment study.

LEVEL

III.

Is Hirschsprung disease a purely neurological condition? A study of the Actin G2 smooth muscle gene in Hirschsprung disease

BACKGROUND

Hirschsprung disease is a functional obstruction of the gastrointestinal tract due to the congenital absence of ganglion cells in the intermyenteric plexuses of the distal bowel. Gastrointestinal motility requires intact muscular layers as well as neural network connection to function properly. The Actin G2 gene is the main gene encoding actin gamma 2; a smooth muscle actin found in enteric tissues.

AIM

This study of the Actin G2 gene in patients with Hirschsprung disease explores a possible molecular basis abnormal muscle function and post-surgical pseudo-obstruction in a group of patients. As far as the authors are aware, this is the first report confirming structural muscle deficits in Hirschsprung disease.

PATIENTS AND METHODS

Ethical permission and informed consent were obtained. DNA was extracted from whole blood samples in 10 patients with histologically proven HSCR patients. PCR amplification of the ACTG2 gene, were subjected to semi-automated bi-directional sequencing analysis. Sequencing results were analyzed using FinchTV Sequence Alignment Software (http:/en.biosoft.net) to read chromatogram files. Further predicting bioinformatic investigation was obtained by PolyPhen 2 software to evaluate the significance of the observed amino acid changes.

RESULTS

Ten new patients with similar HSCR phenotypes were prospectively investigated for variation in the Actin G2 gamma gene (ACTG2) variations. The results of ACTG2 gene analysis showing variation in exons 5, 8 and 10 of the ACTG2 gene in 7 of them (64%). The c.109C > G S345 L was the most frequent occurring in 6 of the 10 patients (54%), the c.171 A > A K119E in 2 and the significant c.108 T > G W357G variation in exon 10 (1 patient) Four patients had a combination of different variants in different exons which were less significant. Allele frequency on a control sample of the South African population showed no comparable pathology link scores (http://gnomad.broadinstitute.org/). Bioinformatic in silico modeling showed that the residue replacements in both variants (Lys to Glu and Trp to Gly) are highly non-conservative and variation can alter interactions within the protein conformation.

CONCLUSIONS

The Actin smooth muscle gene showed variation in 64% of samples, indicating a reason for abnormal functioning muscle in many HSCR patients. Hirschsprung disease is part of a complex spectrum which also includes smooth muscle.

LEVEL OF EVIDENCE

VI.

Genome-wide association analyses identify 139 loci associated with macular thickness in the UK Biobank cohort

The macula, located near the center of the retina in the human eye, is responsible for providing critical functions, such as central, sharp vision. Structural changes in the macula are associated with many ocular diseases, including age-related macular degeneration (AMD) and glaucoma. Although macular thickness is a highly heritable trait, there are no prior reported genome-wide association studies (GWASs) of it. Here we describe the first GWAS of macular thickness, which was measured by spectral-domain optical coherence tomography using 68 423 participants from the UK Biobank cohort. We identified 139 genetic loci associated with macular thickness at genome-wide significance (P < 5 × 10-8). The most significant loci were LINC00461 (P = 5.1 × 10-120), TSPAN10 (P = 1.2 × 10-118), RDH5 (P = 9.2 × 10-105) and SLC6A20 (P = 1.4 × 10-71). Results from gene expression demonstrated that these genes are highly expressed in the retina. Other hits included many previously reported AMD genes, such as NPLOC4 (P = 1.7 × 10-103), RAD51B (P = 9.1 × 10-14) and SLC16A8 (P = 1.7 × 10-8), further providing functional significance of the identified loci. Through cross-phenotype analysis, these genetic loci also exhibited pleiotropic effects with myopia, neurodegenerative diseases (e.g. Parkinson's disease, schizophrenia and Alzheimer's disease), cancer (e.g. breast, ovarian and lung cancers) and metabolic traits (e.g. body mass index, waist circumference and type 2 diabetes). Our findings provide the first insight into the genetic architecture of macular thickness and may further elucidate the pathogenesis of related ocular diseases, such as AMD.

Advances in understanding the association between Down syndrome and Hirschsprung disease (DS-HSCR)

The clinical association between Trisomy 21 (Down syndrome) and aganglionosis (Hirschsprung disease; DS-HSCR) is well-established, being of the order of 5% and remains the most common congenital association with Hirschsprung disease. However, little consensus exists as to the possible etiologic and genetic factors influencing this association. Recent research has identified a number of levels at which development of the enteric nervous system is potentially affected in Trisomy 21. These include a decreased central pool of available neuroblasts for migration into the enteric nervous system, abnormal neuroblast type, poor synaptic nerve function and early germline gene-related influences on the migrating neuroblasts due to genetic mutations of a number of important developmental genes, and possible somatic mutations resulting from alterations in the local tissue microenvironment. In this paper, we review available evidence for this association. In addition, we provide evidence of both germline and somatic gene mutations suggesting causation. Although the picture is complex, recent associations between specific RET proto-oncogene variations have been shown to be significant in Down syndrome patients with Hirschsprung disease, as they probably interfere with vital RET functions in the development of the autonomic and enteric nervous systems, increasing the risk of disturbed normal function. In addition, we explore potential role of other facilitatory influence of other susceptibility genes as well as potential other chromosome 21 gene actions and the microenvironment on the Down syndrome gastro-intestinal tract. The various ways in which trisomy of chromosome influences the enteric nervous system are becoming clearer. The sum of these effects influences the outcome of surgery in Down syndrome patients with Hirschsprung Disease.

Retinoblastoma and Neuroblastoma Predisposition and Surveillance

Retinoblastoma (RB) is the most common intraocular malignancy in childhood. Approximately 40% of retinoblastomas are hereditary and due to germline mutations in the RB1 gene. Children with hereditary RB are also at risk for developing a midline intracranial tumor, most commonly pineoblastoma. We recommend intensive ocular screening for patients with germline RB1 mutations for retinoblastoma as well as neuroimaging for pineoblastoma surveillance. There is an approximately 20% risk of developing second primary cancers among individuals with hereditary RB, higher among those who received radiotherapy for their primary RB tumors. However, there is not yet a clear consensus on what, if any, screening protocol would be most appropriate and effective. Neuroblastoma (NB), an embryonal tumor of the sympathetic nervous system, accounts for 15% of pediatric cancer deaths. Prior studies suggest that about 2% of patients with NB have an underlying genetic predisposition that may have contributed to the development of NB. Germline mutations in ALK and PHOX2B account for most familial NB cases. However, other cancer predisposition syndromes, such as Li-Fraumeni syndrome, RASopathies, and others, may be associated with an increased risk for NB. No established protocols for NB surveillance currently exist. Here, we describe consensus recommendations on hereditary RB and NB from the AACR Childhood Cancer Predisposition Workshop. Clin Cancer Res; 23(13); e98-e106. ©2017 AACRSee all articles in the online-only CCR Pediatric Oncology Series.

Extraskeletal osteosarcoma of the orbit: A clinicopathologic case report and review of literature

Primary extraskeletal osteosarcoma (EOS) is an extremely rare malignancy. In this report, the clinical course of a 32-year-old man presenting with proptoses is described. Medical history included Hirschsprung disease (HD), horseshoe kidney, azoospermia, and vertebral anomalies. Imaging of the orbit showed an oval, well-defined heterogeneous mass adjacent to the lateral wall of the orbit. The patient underwent a lateral orbitotomy and complete excision of the mass. The mass was not attached to the bone. Histopathologic and immunohistochemical examination confirmed the diagnosis of an EOS. The patient received chemotherapy and radiotherapy and is free of the disease 3 years after the diagnosis. Genetic screening showed no mutations for both the RET proto-oncogene for HD and the p53 tumor suppressor gene for osteosarcoma.

Genetic Background of Hirschsprung Disease: A Bridge Between Basic Science and Clinical Application

Hirschsprung's disease (HSCR) is a congenital disorder, defined by partial or complete loss of the neuronal ganglion cells in the intestinal tract, which is caused by the failure of neural crest cells to migrate completely during intestinal development during fetal life. HSCR has a multifactorial etiology, and genetic factors play a key role in its pathogenesis; these include mutations within several gene loci. These have been identified by screening candidate genes, or by conducting genome wide association (GWAS) studies. However, only a small portion of them have been proposed as major genetic risk factors for the HSCR. In this review, we focus on those genes that have been identified as either low penetrant or high penetrant variants that determine the risk of Hirschsprung's disease. J. Cell. Biochem. 119: 28-33, 2018. © 2017 Wiley Periodicals, Inc.

Treatment and Patient Reported Outcome in Children with Hirschsprung Disease and Concomitant Congenital Heart Disease

Purpose. Congenital heart disease (CHD) is reported to be associated with Hirschsprung disease (HD). The aim was to evaluate any differences between children with HD with and without CHD, respectively, with regard to patient characteristics, medical care, and patient reported bowel function. Method. This is a retrospective chart study and a cross-sectional long-term follow-up of patients older than 4 years old, including all children with HD operated on with transanal endorectal pull-through (TERPT) at a tertiary center of pediatric surgery. Information about patient characteristics, diagnostics, surgery, and medical care was compiled. At long-term follow-up, bowel function was assessed by Bowel Function Score. Results. Included were 53 HD-patients, 13 with CHD and 40 without CHD. Children with CHD more commonly presented with failure to thrive; 4 (23%) compared to those without CHD (0%) (p < 0.01). In the long-term follow-up, including 32 patients (6 with CHD), constipation was more commonly reported by children with CHD 5 (83%) than by children without CHD 4 (27%) (p = 0.01). No differences were shown in the other parameters such as fecal control and incontinence. Conclusion. HD-patients with CHD more commonly presented with failure to thrive and more frequently reported constipation than HD-patients without CHD. The findings indicate that HD-patients with CHD might need special consideration in their initial care and long-term follow-up.

Hirschsprung's disease associated with alopecia universalis congenita: a case report

Background

Hirschsprung’s disease is one of the commonest causes of intestinal obstruction in neonates because of gut motility disorder. It is characterized as a complex genetic heterogenous disorder with variable inheritance. Hirschsprung’s disease occurs as an isolated phenotype in majority (70 %) of cases. In other cases it may be associated with syndromes (such as Down’s syndrome, Waardenburg syndrome, congenital central hypoventilation, or cartilage–hair hypoplasia) or with a spectrum of congenital anomalies involving neurological, cardiovascular, or urological systems or with sensorineural anomalies. In our patient, Hirschsprung’s disease was associated with alopecia universalis. Alopecia universalis congenita is a rare disorder of skin characterized by generalized absence of hair at or shortly after birth. The inheritance patterns range from autosomal recessive, dominant or X-linked recessive forms. The autosomal recessive form is the most common and severe type in which patients present with complete absence of hair development, affecting the entire scalp and body. Alopecia universalis congenita occurs either in isolation or as a part of congenital syndromes. Here, we report the case of a neonate who presented with Hirschsprung’s disease with alopecia universalis congenita, an association which has not been reported before.

Case presentation

A preterm (33 weeks’ gestation) 1.4 kg Indian baby girl was born to a gravida two mother by caesarean section. At birth, clinical examination revealed total absence of scalp and body hair. On day 3, she had bilious vomiting and a barium study was suggestive of Hirschsprung’s disease. An exploratory laparotomy and intestinal biopsy report revealed aganglionic muscularis propria; a skin biopsy from her scalp was suggestive of alopecia universalis. Postoperatively, she died due to multiorgan failure. Her family history revealed that her elder sibling also had alopecia universalis and esophageal atresia. This child died on day twelve. Our patient’s clinical features and the biopsy reports confirmed our diagnosis of Hirschsprung’s disease with alopecia universalis congenita.

Conclusions

A diagnosis of Hirschsprung’s disease should make treating clinicians actively investigate for any associated syndromes and anomalies. Alopecia is an unusual association with Hirschsprung’s disease. Alopecia universalis congenita is the most severe form of alopecia areata. Early diagnosis and classification is essential for appropriate and timely management of such cases.

Syndromic Hirschsprung's disease and associated congenital heart disease: a systematic review

PURPOSE

Hirschsprung's disease (HD) occurs as an isolated phenotype in 70% of infants and is associated with additional congenital anomalies or syndromes in approximately 30% of patients. The cardiac development depends on neural crest cell proliferation and is closely related to the formation of the enteric nervous system. HD associated with congenital heart disease (CHD) has been reported in 5-8% of cases, with septation defects being the most frequently recorded abnormalities. However, the prevalence of HD associated with CHD in infants with syndromic disorders is not well documented. This systematic review was designed to determine the prevalence of CHD in syndromic HD.

METHODS

A systematic review of the literature using the keywords "Hirschsprung's disease", "aganglionosis", "congenital megacolon", "congenital heart disease" and "congenital heart defect" was performed. Resulting publications were reviewed for epidemiology and morbidity. Reference lists were screened for additional relevant studies.

RESULTS

A total of fifty-two publications from 1963 to 2014 reported data on infants with HD associated with CHD. The overall reported prevalence of HD associated with CHD in infants without chromosomal disorders was 3%. In infants with syndromic disorders, the overall prevalence of HD associated with CHD ranged from 20 to 80 % (overall prevalence 51%). Septation defects were recorded in 57% (atrial septal defects in 29%, ventricular septal defects in 32%), a patent ductus arteriosus in 39%, vascular abnormalities in 16%, valvular heart defects in 4% and Tetralogy of Fallot in 7%.

CONCLUSION

The prevalence of HD associated with CHD is much higher in infants with chromosomal disorders compared to infants without associated syndromes. A routine echocardiogram should be performed in all infants with syndromic HD to exclude cardiac abnormalities.

[Analysis of Environmental-Stress-Related Impairments of Inner Ear]

Noise stress generated in industry is one of the environmental factors that physically affects the functions of the inner ear. Exposure to noise can cause hearing loss, resulting in serious problems in occupational and daily life. At present, however, there are very limited ways to prevent hearing impairments. The inner ear consists of the organ of Corti, vestibule and semicircular canal. Functional or morphological damage of these tissues in the inner ear caused by genetic factors, aging or environmental factors can result in hearing or balance impairments. In this review, we first introduce a deafness-related molecule found by our clinical research. Our experimental research using genetically engineered mice further demonstrated that impaired activity of the target molecule caused congenital and age-related hearing loss with neurodegeneration of spiral ganglion neurons in the inner ears. We also describe impaired balance in mice caused by exposure to low-frequency noise under experimental conditions with indoor environmental monitoring. We believe that our approaches to pursue both experimental research and fieldwork research complementarily are crucial for the development of a method for prevention of impairments of the inner ear.

Clinical and genetic correlations of familial Hirschsprung's disease

BACKGROUND

The risk of familial transmission in Hirschsprung's disease (HSCR) currently lacks correlation between the clinical phenotype and the underlying genetic factors. The aim of this study was to clinically evaluate familial HSCR transmission and to correlate with the genetic background.

METHODS

Clinical and gene analysis of familial HSCR patients were explored. DNA from 45 patients (35 kindreds) was screened for genetic variations of the RET, and EDNRB genes were screened for genetic variation by semi-automated bi-directional sequencing analysis and matched to controls.

MAIN RESULTS

Male:female ratio (3:1) had a female proband in 4 families. Aganglionosis was significantly more frequent with total colonic aganglionosis (TCA) in 40% familial cases (viz: 17/43 (43%) vs. 19/342 non-familial patients (5.6%) (p<0.01)). Transmission of S-HSCR was observed in 13 (31%), which was associated with EDNRB variation. RET gene promoter variation correlated with extended aganglionosis in 6/35 kindreds (17%). In 3 kindreds, both significant EDNRB and RET mutations were identified and where present were associated with increased penetrance in succeeding generations. An increased penetrance with succeeding generations occurred in 6 (14%). In a further 3 generation family, extensive variations in exon 6, 13, and 18 affected 3 males with progressive penetration and aganglionic length, including total intestinal aganglionosis in the further offspring. RET and MEN association was noted in 5 kindreds (14.3%) related to RET variations at Cysteine sites.

CONCLUSIONS

Cumulative effects of the RET and EDNRB genes contribute to long-segment and total colonic aganglionosis.

Total colonic aganglionosis and Hirschsprung's disease: a review

Total colonic aganglionosis is a relatively uncommon form of Hirschsprung's disease (HSCR). It occurs in approximately 2-13 % of HSCR cases and involves the entire colon which is aganglionic but may extend proximally into varying lengths of small bowel. As a result, it should be separated into Total colonic aganglionosis (TCA) [defined as aganglionosis extending from the anus to at least the ileocaecal valve but no more than 50 cm small bowel proximal to the ileocaecal valve] and total colonic and small bowel aganglionosis (TCSA) which may involve very long segments of small bowel aganglionosis. Clinically, TCA appears to represent a different spectrum of disease in terms of presentation and difficulties which may be experienced in diagnosis suggesting a different pathophysiology from the more common forms of HSCR. It is therefore not yet clear whether TCA merely represents a long form of HSCR or a different expression of the disease. A number of differences exist between TCA and other forms of HSCR which require explanation if its ubiquitous clinical features are to be understood. In addition to the usual explanations for the aganglionosis of HSCR, there is some evidence suggesting that in place of being purely congenital, it may represent certain different pathophysiologic mechanisms, some of which may continue to be active after birth. This study reviews what is known about the clinical, radiological and histopathologic differences between TCA and the more frequently encountered recto-sigmoid (or short-segment; S-HSCR) and correlates them with what is currently known about the genetic and molecular biologic background to find possible pathogenetic mechanisms.

Hirschsprung's Disease and Associated Congenital Heart Defects: A Prospective Observational Study from a Single Institution

OBJECTIVE

To define the prevalence and characteristics of associated congenital heart diseases (CHDs) in patients with Hirschsprung's disease (HSCR).

METHOD

All patients with a histological diagnosis of HSCR admitted to our hospital between January 2010 and December 2013 were included in this prospective observational study and underwent cardiovascular screening. Cardiac anatomy was assessed by a segmental echocardiographic approach. Measurements of aortic root and left ventricular dimensions, wall thickness, and function were obtained. CHDs requiring a percutaneous or surgical intervention were described as major heart diseases.

RESULTS

One hundred thirty-three consecutive patients were enrolled at median age of 2.3 years. Eleven patients (8.3%) presented an associated heart disease. Moreover, five patients had mild dilatation of aortic root. Six out of 11 (4.5%) patients had a major CHDs requiring surgical repair.

CONCLUSION

Prevalence of associated CHDs was slightly higher than in previous papers, and mostly represented by septal defects. Four out of six patients with major heart disease had also a chromosomal anomaly. If we do not consider the subpopulation of patients with a chromosomal anomaly, cardiac defects were present in 3.8% of the patients. Based on these results, we suggest to perform routine echocardiogram in all Hirschsprung patients, with or without associated chromosomal syndromes.

Congenital anomalies of the kidney and urinary tract (CAKUT) associated with Hirschsprung's disease: a systematic review

PURPOSE

Congenital anomalies of the kidney and urinary tract (CAKUT), a term introduced in the late 1990 s accounts for 30-50 % of cases of end-stage renal disease in children. The association of urogenital anomalies and Hirschsprung's disease (HSCR) based on the common genetic background of enteric nervous system and human urinary tract development has been well described in the literature. However, the reported prevalence of HSCR associated with CAKUT seems to be underestimated. The aim of this systematic review was to determine the prevalence of this association and show its relationship to other syndromes.

METHODS

A systematic literature search was conducted for relevant articles published between 1955 and 2014. Two online databases were searched for the terms "Hirschsprung's disease", "congenital anomalies of the kidney and urinary tract", "urogenital anomalies" and "urological anomalies". All published studies containing adequate clinical data were included. Resulting publications were reviewed for epidemiology, genetic testing, operative treatment and morbidity. Reference lists were screened for additional cases.

RESULTS

A total of 32 articles reported 222 cases of HSCR associated with either CAKUT, "urological" or "urogenital" anomalies from 1955 to 2014. Gender was reported in a total of 68 cases, with 54 (79 %) males and 14 (21 %) females. Extent of aganglionosis was reported in 67 cases and included classical rectosigmoid disease in 38, long-segment aganglionosis in 12, total colonic aganglionosis in 12 and total intestinal aganglionosis in 5 patients. 18 articles reported 204 cases of either CAKUT, "urological" or "urogenital" anomalies in a case series of 5.693 HSCR patients, resulting in an overall prevalence of 3.6 % of this association. Within this collective of 18 studies only seven were, regardless of the date of publication compatible with CAKUT criteria introduced and published in the late 1990 s. These seven studies reported a total of 72 patients with associated CAKUT among 757 HSCR patients resulting in a prevalence of 9.5 %. After introduction of the CAKUT acronym, only three studies specifically investigated the association of HSCR and CAKUT stating a prevalence of 14.3 % resulting in an almost fivefold increase compared to the reported prevalence of HSCR and associated urological and urogenital anomalies. The remaining 14 publications reported 18 single cases of HSCR patients with associated CAKUT phenotypes. Of these 18 cases, 11 (61 %) cases were associated with other syndromes or syndromatic features or reported chromosomal anomalies.

CONCLUSION

This review confirms that the recognition of CAKUT in HSCR patients has been underestimated in the past. The results suggest that when confronted with HSCR in a patient, a thorough urological investigation may be indicated. The high prevalence of associated syndromes in HSCR with CAKUT may further suggest a syndromic association.

Prevalence of Hirschsprung's disease in premature infants: a systematic review

PURPOSE

Intestinal dysmotility in preterm infants has often been attributed to immature enteric nervous system. It is frequently reported that Hirschsprung's disease (HD) is rare in premature infants. The exact prevalence of HD in premature infants is not well documented. The classical signs of HD may often not be identified due to the complexity of symptoms of prematurity itself. This systematic review was designed to determine the prevalence and presentation of HD in premature infants.

METHODS

A systematic review of the literature using the keywords "Hirschsprung's disease", "aganglionosis", "congenital megacolon", "premature" and "preterm" was performed. Resulting publications were reviewed for epidemiology and morbidity. Only infants born <37 weeks of gestation or described as preterm birth by the authors were included. Reference lists were screened for additional relevant studies.

RESULTS

Twenty-six publications from 1964 to 2013 reported data on premature infants with HD. Out of a total number of 4,147 infants, prematurity was recorded in 257 cases, giving a prevalence rate of 6 % of preterm infants diagnosed with HD. During 1964-1999, reported prevalence of HD in premature infants ranged from 1.7 to 9.2 % (overall prevalence 5 %) and during 2000-2013 prevalence ranged from 4 to 19.4 % (overall prevalence 14 %). The prevalence of total colonic aganglionosis in premature infants was 13 % (15 out of 118 infants). Mean gestational age of preterm infants was 34.5 (± 0.7) weeks and mean age at diagnosis ranged from 18.3 days to 3.9 months. Abdominal distension was observed in 80 % of preterm infants, delayed passage of meconium in 57 and 37 % of premature infants presented with bile-stained vomiting.

CONCLUSION

In recent years, higher prevalence of HD has been reported in premature infants compared to previous years. Hirschsprung's disease should be considered in preterm infants presenting with features of intestinal obstruction.

Hirschsprung's disease prevalence in Europe: a register based study

BACKGROUND

Hirschsprung's disease is a congenital gut motility disorder, characterised by the absence of the enteric ganglion cells along the distal gut. The aim of this study was to describe the epidemiology of Hirschsprung's disease, including additional congenital anomalies, total prevalence, trends, and association with maternal age.

METHODS

Cases of Hirschsprung's disease delivered during 1980 to 2009 notified to 31 European Surveillance of Congenital Anomaly registers formed the population-based case-series. Prevalence rates and 95% confidence intervals were calculated as the number of cases per 10,000 births. Multilevel Poisson regression was performed to investigate trends in prevalence, geographical variation and the association with maternal age.

RESULTS

There were 1,322 cases of Hirschsprung's disease among 12,146,210 births. The total prevalence was 1.09 (95% confidence interval, 1.03-1.15) per 10,000 births and there was a small but significant increase in prevalence over time (relative risk = 1.01; 95% credible interval, 1.00-1.02; p = 0.004). There was evidence of geographical heterogeneity in prevalence (p < 0.001). Excluding 146 (11.0%) cases with chromosomal anomalies or genetic syndromes, there were 1,176 cases (prevalence = 0.97; 95% confidence interval, 0.91-1.03 per 10,000 births), of which 137 (11.6%) had major structural anomalies. There was no evidence of a significant increased risk of Hirschsprung's disease in cases born to women aged ≥35 years compared with those aged 25 to 29 (relative risk = 1.09; 95% credible interval, 0.91-1.31; p = 0.355).

CONCLUSION

This large population-based study found evidence of a small increasing trend in Hirschsprung's disease and differences in prevalence by geographic location. There was also no evidence of an association with maternal age.

[Ejaculatory system cysts: a case report]

INTRODUCTION

Male pelvic floor cysts are a rare clinical entity that include: Wolffian duct remnants, Müllerian duct remnants, cysts of the seminal vesicles, prostate and ejaculatory duct/vas deferens cysts.


CASE REPORT

We report the clinical case of a 21-year-old male patient with a history of previous surgery in childhood and more precisely: partial colectomy for congenital megacolon, removal of dysplastic right kidney and subsequent surgical adhesiolysis for bowel obstruction.
 At 17, the patient was submitted to MRI for groin pain with an incidental finding of a cystic mass at the level of the right seminal vesicle. Consequently, a TUR-ED was performed at another urology unit, for a suspected seminal vesicle ectasia, without resolution of pain symptoms. The patient was referred to us for persistent genitourinary infections, ejaculation disorder and episodes of gross hematuria. An additional MRI confirmed the presence of a cystic mass of 5,5 cm with a suspected opening into prostatic urethra. Urethrocystoscopy and urethrocystography retrograde confirmed this anatomical communication. For the persistence of the symptoms we performed retropubic surgical exeresis of the mass, with a histopathological finding of benign cyst of the vas deferens.
 Two major postoperative complications were reported: a pelvic hematoma that required surgical exploration and a urinary extravasation at the level of prostatic urethra, which resolved with prolonged urethral catheterization.


CONCLUSIONS

Male pelvic floor cysts are a rare disease with a complex clinical and therapeutic management. A correct diagnosis is based on clinical signs and symptoms together with imaging studies of the pelvic region. The high risk of erectile dysfunction and ejaculatory disorders correlated to a surgical approach, recommend a treatment of these lesions only for symptomatic cases.

Advances in Hirschsprung disease genetics and treatment strategies: an update for the primary care pediatrician

Hirschsprung disease (HSCR) is a multigenic condition with variable presentation. Most commonly, it presents in the neonatal period as a functional intestinal obstruction secondary to failure of caudal migration of the enteric nervous system. Classically, this manifests as dilated proximal bowel and constricted distal bowel with absent ganglia and hypertrophic nerve trunks. When recognized early, medical and surgical therapies can be instituted to minimize associated morbidity and mortality. This article reviews current understanding of the etiology of HSCR, its multigenic associations, the historical evolution of HSCR diagnosis and treatment, and current HSCR therapies.

Mowat-Wilson syndrome: the first report of an association with central nervous system tumors

Mowat-Wilson syndrome (MWS) is a rare genetic condition where variable and multiple congenital anomalies including Hirschsprung's disease, intellectual disability, and prominent facial features are present. At molecular level, MWS is characterized by many different described mutations in the zinc finger E-box protein 2 (ZEB2) gene, ultimately leading to loss of gene function. This report is the first to describe the association of MWS with two different asynchronous malignant brain tumors (medulloblastoma and glioblastoma) occurring in a child.

A prospective observational study of associated anomalies in Hirschsprung's disease

BACKGROUND

Associated anomalies have been reported in around 20% of Hirschsprung patients but many Authors suggested a measure of underestimation. We therefore implemented a prospective observational study on 106 consecutive HSCR patients aimed at defining the percentage of associated anomalies and implementing a personalized and up-to-date diagnostic algorithm.

METHODS

After Institutional Ethical Committee approval, 106 consecutive Hirschsprung patients admitted to our Institution between January 2010 and December 2012 were included. All families were asked to sign a specific Informed Consent form and in case of acceptance each patient underwent an advanced diagnostic algorithm, including renal ultrasound scan (US), cardiologic assessment with cardiac US, cerebral US, audiometry, ENT and ophthalmologic assessments plus further specialist evaluations based on specific clinical features.

RESULTS

Male to female ratio of our series of patients was 3,4:1. Aganglionosis was confined to the rectosigmoid colon (classic forms) in 74,5% of cases. We detected 112 associated anomalies in 61 (57,5%) patients. The percentage did not significantly differ according to gender or length of aganglionosis. Overall, 43,4% of patients complained ophthalmologic issues (mostly refraction anomalies), 9,4% visual impairment, 20,7% congenital anomalies of the kidney and urinary tract, 4,7% congenital heart disease, 4,7% hearing impairment or deafness, 2,3% central nervous system anomalies, 8,5% chromosomal abnormalities or syndromes and 12,3% other associated anomalies.

CONCLUSIONS

Our study confirmed the underestimation of certain associated anomalies in Hirschsprung patients, such as hearing impairment and congenital anomalies of the kidney and urinary tract. Subsequently, based on our results we strongly suggest performing renal US and audiometry in all patients. Conversely, ophthalmologic assessment and cerebral and heart US can be performed according to guidelines applied to the general population or in case of patients with suspected clinical features or chromosomal abnormalities. This updated diagnostic algorithm aims at improving overall outcome thanks to better prognostic expectations, prevention strategies and early rehabilitation modalities. The investigation of genetic background of patients with associated anomalies might be the next step to explore this intriguing multifactorial congenital disease.

Contribution of rare and common variants determine complex diseases-Hirschsprung disease as a model

Finding genes for complex diseases has been the goal of many genetic studies. Most of these studies have been successful by searching for genes and mutations in rare familial cases, by screening candidate genes and by performing genome wide association studies. However, only a small fraction of the total genetic risk for these complex genetic diseases can be explained by the identified mutations and associated genetic loci. In this review we focus on Hirschsprung disease (HSCR) as an example of a complex genetic disorder. We describe the genes identified in this congenital malformation and postulate that both common 'low penetrant' variants in combination with rare or private 'high penetrant' variants determine the risk on HSCR, and likely, on other complex diseases. We also discuss how new technological advances can be used to gain further insights in the genetic background of complex diseases. Finally, we outline a few steps to develop functional assays in order to determine the involvement of these variants in disease development.

Involvement of down-regulated E2F3 in Hirschsprung's disease

BACKGROUND/PURPOSE

Hirschsprung's disease (HSCR) is a common cause of neonatal bowel obstruction characterized by the absence of ganglion cells in the colon. Impaired migration of the neural crest cells (NCCs) has been implicated as one of the main causes of HSCR. E2F3, a member in the E2F family, which plays a crucial role in the control of the cell cycle is correlated with neuron migration. However, the function of E2F3 in the development of the enteric nervous system still remains unknown. This study aims to reveal the correlation of E2F3 in the progress of HSCR.

METHODS

By using reverse transcriptase polymerase chain reaction (RT-PCR) and western blot assay, we investigated levels of E2F3 expression in 58 HSCR patients, both in the aganglionic bowel segment and the normal ganglionic segment, and in 39 unrelated controls. By in vitro assays, we used the siRNA method to knock-down the level of E2F3 expression in 293T cell lines. Furthermore, transwell assay was used to detect cell migration ability.

RESULTS

Aberrant lower expression level of E2F3 was detected in the HSCR-S segment compared with the control group by RT-PCR and western blot assay. Besides, down-regulated E2F3 could suppress the cell migration.

CONCLUSIONS

This is the first study showing the down-regulation of E2F3 in HSCR, bringing new insight to the mechanism of the impaired migration of neural crest cells.

Total colonic aganglionosis in Hirschsprung disease

Total colonic aganglionosis (TCA) is a relatively uncommon form of Hirschsprung disease (HSCR), occurring in approximately 2%-13% of cases. It can probably be classified as TCA (defined as aganglionosis extending from the anus to at least the ileocecal valve, but not >50 cm proximal to the ileocecal valve) and total colonic and small bowel aganglionosis, which may involve a very long segment of aganglionosis. It is not yet clear whether TCA merely represents a long form of HSCR or a different expression of the disease. There are many differences between TCA and other forms of HSCR, which require explanation if its ubiquitous clinical features are to be understood. Clinically, TCA appears to represent a different spectrum of disease in terms of presentation and difficulties that may be experienced in diagnosis, suggesting a different pathophysiology from the more common forms of HSCR. There is also some evidence suggesting that instead of being purely congenital, it may represent certain different pathophysiologic mechanisms. This study, in addition to reviewing current understanding and differences between TCA and the more frequently encountered rectosigmoid (or short-segment) expression, correlates them with what is currently known about the genetic and molecular biological background. Moreover, it reviews current outcomes to find consensus on management.

Chromosomal and related Mendelian syndromes associated with Hirschsprung's disease

Hirschsprung's disease (HSCR) is a fairly frequent cause of intestinal obstruction in children. It is characterized as a sex-linked heterogonous disorder with variable severity and incomplete penetrance giving rise to a variable pattern of inheritance. Although Hirschsprung's disease occurs as an isolated phenotype in at least 70% of cases, it is not infrequently associated with a number of congenital abnormalities and associated syndromes, demonstrating a spectrum of congenital anomalies. Certain of these syndromic phenotypes have been linked to distinct genetic sites, indicating underlying genetic associations of the disease and probable gene-gene interaction, in its pathogenesis. These associations with HSCR include Down's syndrome and other chromosomal anomalies, Waardenburg syndrome and other Dominant sensorineural deafness, the Congenital Central Hypoventilation and Mowat-Wilson and other brain-related syndromes, as well as the MEN2 and other tumour associations. A number of other autosomal recessive syndromes include the Shah-Waardenburg, the Bardet-Biedl and Cartilage-hair hypoplasia, Goldberg-Shprintzen syndromes and other syndromes related to cholesterol and fat metabolism among others. The genetics of Hirschsprung's disease are highly complex with the majority of known genetic sites relating to the main susceptibility pathways (RET an EDNRB). Non-syndromic non-familial, short-segment HSCR appears to represent a non-Mendelian condition with variable expression and sex-dependent penetrance. Syndromic and familial forms, on the other hand, have complex patterns of inheritance and being reported as autosomal dominant, recessive and polygenic patterns of inheritance. The phenotypic variability and incomplete penetrance observed in Hirschsprung's disease could also be explained by the involvement of modifier genes, especially in its syndromic forms. In this review, we look at the chromosomal and Mendelian associations and their underlying signalling pathways, to obtain a better understanding of the pathogenetic mechanisms involved in developing aganglionosis of the distal bowel.

The many faces of RET dysfunction in kidney

Signaling pathways that are activated upon interaction of glial cell-line derived neurotrophic factor (Gdnf), its coreceptor Gfra1, and receptor tyrosine kinase Ret are critical for kidney development and ureter maturation. Outside the kidney, this pathway is implicated in a number of congenital diseases including Hirschsprung disease (intestinal aganglionosis, HSCR) and hereditary cancer syndromes (MEN 2). Total lack of Gdnf, Gfra1 or Ret in mice results in perinatal lethality due to bilateral renal agenesis or aplasia. In humans, RET mutations have been identified in a spectrum of congenital malformations involving the RET axis including isolated HSCR, isolated congenital anomalies of kidney or urinary tract (CAKUT), or CAKUT and HSCR together. The molecular basis for these pleiotropic effects of RET has just begun to be unraveled. In an effort to delineate the pathogenetic mechanisms that underlie these congenital malformations, we and others have characterized Ret's role in early kidney and urinary system development. Here we present a brief overview of the "many faces" of Ret dysfunction in kidney with particular emphasis on Ret's signaling specificity and intergenic interactions that confer normal urinary system development.

Aberrant high expression of NRG1 gene in Hirschsprung disease

BACKGROUND/PURPOSE

Hirschsprung disease (HSCR) is a congenital disorder characterized by the absence of intramural ganglion cells along with variable lengths of the gastrointestinal tract. Recent studies have indicated the potential function of neuregulin-1 (NRG1) in HSCR, which encodes the heregulins and other mitogenic ligands for the ErbB family. The purpose of this study was to further clarify the role of NRG1 in the pathogenesis of HSCR.

METHODS

We examined the NRG1 messenger RNA (messenger RNA) and protein expression levels in gut tissues of 63 patients with sporadic HSCR (both stenotic and dilated gut tissues) and 35 controls. Moreover, using the methylation-specific polymerase chain reaction, we examined the methylation pattern of exon 1 of the NRG1 gene.

RESULTS

The mRNA expression levels of NRG1 were significantly higher in tissues of HSCR than those in controls, and the increased NRG1 protein levels in HSCR were consistent with the mRNA levels. However, no methylation pattern change was observed in exon 1 of the gene among different groups.

CONCLUSIONS

Our study demonstrates that the aberrant expression of NRG1 may play an important role in the pathology of HSCR. DNA methylation of the gene seems not to be involved in the mechanism of such aberrant expression, and other factors should be explored.

Hearing impairments caused by genetic and environmental factors

Impairments of hearing and balance are major problems in the field of occupational and environmental health. Such impairments have previously been reported to be caused by genetic and environmental factors. However, their mechanisms have not been fully clarified. On the other hand, the inner ear contains spiral ganglion neurons (SGNs) in the organ of Corti, which serve as the primary carriers of auditory information from sensory cells to the auditory cortex in the cerebrum. Inner ears also contain a vestibule in the vicinity of the organ of Corti—one of the organs responsible for balance. Thus, inner ears could be a good target to clarify the pathogeneses of sensorineural hearing losses and impaired balance. In our previous studies with c-Ret knock-in mice and Endothelin receptor B (Ednrb) knock-out mice, it was found that syndromic hearing losses involved postnatal neurodegeneration of SGNs caused by impairments of c-Ret and Ednrb, which play important roles in neuronal development and maintenance of the enteric nervous system. The organ of Corti and the vestibule in inner ears also suffer from degeneration caused by environmental stresses including noise and heavy metals, resulting in impairments of hearing and balance. In this review, we introduce impairments of hearing and balance caused by genetic and environmental factors and focus on impairments of SGNs and the vestibule in inner ears as the pathogeneses caused by these factors.