A lmod1a mutation causes megacystis microcolon intestinal hypoperistalsis in a CRISPR/Cas9-modified zebrafish model.

PURPOSE: Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is defined as a congenital visceral myopathy with genetic mutations. However, the etiology and pathophysiology are not fully understood. We aimed to generate a gene leiomodin-1a (lmod1a) modification technique to establish a zebrafish model of MMIHS. METHODS: We targeted lmod1a in zebrafish using CRISPR/Cas9. After confirming the genotype, we measured the expression levels of the target gene and protein associated with MMIHS. A gut transit assay and spatiotemporal mapping were conducted to analyze the intestinal function. RESULTS: Genetic confirmation showed a 5-base-pair deletion in exon 1 of lmod1a, which caused a premature stop codon. We observed significant mRNA downregulation of lmod1a, myh11, myod1, and acta2 and the protein expression of Lmod1 and Acta2 in the mutant group. A functional analysis of the lmod1a mutant zebrafish showed that its intestinal peristalsis was fewer, slower, and shorter in comparison to the wild type. CONCLUSION: This study showed that targeted deletion of lmod1a in zebrafish resulted in depletion of MMIHS-related genes and proteins, resulting in intestinal hypoperistalsis. This model may have the potential to be utilized in future therapeutic approaches, such as drug discovery screening and gene repair therapy for MMIHS.

Management of urinary incontinence in girls with congenital pouch colon.

PURPOSE: This study describes the management of urinary incontinence (UI) in eight girls with congenital pouch colon (CPC) associated with anorectal malformation (ARM). METHODS: From 2013 to 2015, six girls with CPC and UI underwent bladder neck reconstruction (BNR). Four girls had complete UI (CUI) and two girls partial UI (PUI). From 2019 to 2023, four girls, including two with failed BNR, underwent bladder neck closure (BNC) and augmentation cystoplasty (AC) with a continent stoma. Subtypes of CPC were Complete CPC (n = 7) and Incomplete CPC (n = 1). All girls had a double vagina; short, wide urethra; and reduced bladder capacity with an open, incompetent bladder neck (BNI). During BNR, a neourethra was constructed from a 1.5-2 cm-wide and 1.5-3-cm-long trigonal strip. During BNC, AC was performed using a 20 cm ileal segment (n = 3) and by a colonic pouch segment, preserved during earlier colorraphy (n = 1). Continent stoma included a Monti's channel (n = 3) and appendicovesicostomy (n = 1). RESULTS: BNR produced moderate improvement of UI (n = 2), while UI was still very severe (n = 4). During BNC, intraoperative complications included iatrogenic vaginal tears (n = 4). Early complications included partial dehiscence of the ileocystoplasty (n = 1), partial adhesive small bowel obstruction (n = 1), and difficulty in stomal catheterization with prolonged drainage from the pelvic drain (n = 1). Late complications included unilateral grade II vesicoureteric reflux (n = 2) and vesicovaginal fistula (VVF) (n = 2) needing trans-vaginal closure in one girl. Urinary stones (n = 2) with stomal leakage of urine in one girl needed open cystolithotomy twice (n = 1), and endoscopic lithotripsy (n = 1). At follow-up, all patients have high overall satisfaction with the procedure and their continence status. CONCLUSIONS: BNC with AC and a catheterizable stoma satisfactorily achieves continence in girls with CPC and UI, vastly improving quality of life. If lower urinary tract (LUT) anatomy is favorable, BNR with/without AC can be the initial surgical procedure. BNC should be the primary procedure in girls with unfavorable LUT anatomy and for failed BNR. LEVEL OF EVIDENCE: IV.

Megacystis-microcolon-intestinal hypoperistalsis syndrome: don't forget the bladder.

PURPOSE: Megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS) is a well described clinical condition, but reports are focused on microcolon and intestinal hypoperistalsis, while data on bladder management are scant. Aim of the study is to present urological concerns in MMIHS. METHODS: Retrospective evaluation of clinical data on urological management of MMIHS patients treated in the last 10 years. RESULTS: Six patients were enrolled (3 male, 3 female). Three girls had prenatal diagnosis of megacystis (1 vesicoamniotic shunt was placed). All patients had genetic diagnosis: 5 had ACTG2 gene mutations and 1 MYH11 mutation. All patients were addressed to our attention for urinary symptoms, such as urinary retention, urinary tract infections, acute renal injury. Two patients presented frequent stoma prolapses. All children underwent a complete urological evaluation, and then started a bladder management protocol (clean intermittent catheterization, via urethra or cystostomy-tube placement), with improvement of urinary infections, upper urinary tract dilation and stoma prolapses, if present. All patients had good renal function at last follow-up. CONCLUSION: We believe that MMIHS patients must be addressed soon and before onset of symptoms for a multidisciplinary evaluation, including an early assessment by a pediatric urologist expert in functional disorder, to preserve renal function at its best.

Genome-wide analysis identifies MYH11 compound heterozygous variants leading to visceral myopathy corresponding to late-onset form of megacystis-microcolon-intestinal hypoperistalsis syndrome.

Megacystis-microcolon-hypoperistalsis-syndrome (MMIHS) is a rare and early-onset congenital disease characterized by massive abdominal distension due to a large non-obstructive bladder, a microcolon and decreased or absent intestinal peristalsis. While in most cases inheritance is autosomal dominant and associated with heterozygous variant in ACTG2 gene, an autosomal recessive transmission has also been described including pathogenic bialellic loss-of-function variants in MYH11. We report here a novel family with visceral myopathy related to MYH11 gene, confirmed by whole genome sequencing (WGS). WGS was performed in two siblings with unusual presentation of MMIHS and their two healthy parents. The 38 years-old brother had severe bladder dysfunction and intestinal obstruction, whereas the 30 years-old sister suffered from end-stage kidney disease with neurogenic bladder and recurrent sigmoid volvulus. WGS was completed by retrospective digestive pathological analyses. Compound heterozygous variants of MYH11 gene were identified, associating a deletion of 1.2 Mb encompassing MYH11 inherited from the father and an in-frame variant c.2578_2580del, p.Glu860del inherited from the mother. Pathology analyses of the colon and the rectum revealed structural changes which significance of which is discussed. Cardiac and vascular assessment of the mother was normal. This is the second report of a visceral myopathy corresponding to late-onset form of MMIHS related to compound heterozygosity in MYH11; with complete gene deletion and a hypomorphic allele in trans. The hypomorphic allele harbored by the mother raised the question of the risk of aortic disease in adults. This case shows the interest of WGS in deciphering complex phenotypes, allowing adapted diagnosis and genetic counselling.

Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS): challenges in diagnosis and management.

Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a rare, congenital functional intestinal obstruction, characterised by megacystis (bladder distention in the absence of mechanical obstruction), microcolon and intestinal hypoperistalsis (dysmotility).We are reporting a case of a female child with normal antenatal course who presented with recurrent episodes of abdominal distension since the second day of life and underwent negative exploratory laparotomy on multiple occasions. She also had urinary retention with a grossly distended bladder, requiring drainage by clean intermittent catheterisation. Surgical procedures for bowel decompression, including gastrostomy and ileostomy, were carried out without success. Genetic analysis revealed a mutation in the human smooth muscle (enteric) gamma-actin gene (ACTG2 gene), clinching the diagnosis of MMIHS. The patient was managed with parenteral nutrition and prokinetic medications and tolerated jejunostomy feeds for a brief period before she succumbed to the illness.Female neonates or infants presenting with abdominal distension and dilated urinary tract should be investigated for MMIHS early on. A timely diagnosis will enable the early involvement of a multidisciplinary team to provide the best options available for management.

Exploring the complexities of megacystis-microcolon-intestinal hypoperistalsis syndrome: insights from genetic studies.

Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is an uncommon genetic disorder inherited in an autosomal recessive pattern that affects the muscles that line the bladder and intestines. The most common genes associated with MMIHS mutations are ACTG2, LMOD1, MYH11, MYL9, MYLK, and PDCL3. However, the complete genetic landscape of MMIHS still needs to be fully understood. The diagnosis of MMIHS can be challenging. However, advances in prenatal and diagnostic techniques, such as ultrasound and fetal urine analysis, have improved the ability to detect the syndrome early. Targeted next-generation sequencing (NGS) and other diagnostic tests can also diagnose MMIHS. The management of MMIHS involves addressing severe intestinal dysmotility, which often necessitates total parenteral nutrition (TPN), which can lead to complications such as hepatotoxicity and nutritional deficiencies. Multivisceral and intestinal transplantation has emerged as therapeutic options, offering the potential for improved outcomes and enteral autonomy. Understanding the genetic underpinnings of MMIHS is crucial for personalized care. While the prognosis varies, timely interventions and careful monitoring enhance patient outcomes. Genetic studies have given us valuable insights into the molecular mechanisms of MMIHS. These studies have identified mutations in genes involved in the development and function of smooth muscle cells. They have also shown that MMIHS is associated with defects in the signaling pathways that control muscle contraction. Continued research in the genetics of MMIHS holds promise for unraveling the complexities of MMIHS and improving the lives of affected individuals.

CLINICAL FEATURES OF THE COURSE OF HIRSCHSPRING'S DISEASE INCHILDREN OF THE FIRST YEAR.

The purpose of the work - to investigate the peculiarities of the clinical course of Hirschsprung's disease in children of the first year of life and to determine the significance of symptoms in the verification of the disease. From 1980 to 2021, at the pediatric surgery clinic of the National Medical University named after O.O. Bogomolets on the basis of the National Children's Specialized Hospital "OKHMATDYT" and in the pediatric surgery clinic of the Ivano-Frankivsk National Medical University on the basis of the Ivano-Frankivsk Regional Children's Clinical Hospital, 483 children of the first year of life suffering from Hirschsprung's disease were examined and treated. The clinical manifestation and course of aganglionosis varied in length at the time of hospitalization and depended on the time after birth. During the first month of life, 97 (20.08%) patients were hospitalized, of which 39 (8.07%) hadatypical clinical picture due to: colonic atresia in 15 (3.10%), colonic atresia + gastroschisis in 3 (0.62%), ileal atresia in 9 (1.86%), esophageal atresia in 3 (0 .62%), clefts of the hard and soft palate in 9 (1.86%). Depending on the age, there were 280 (57.97%) patients under 6 months, and 203 (42.03%) patients between 6 months and 1 year. The classic typical clinical picture was in 444 (91.93%) patients, which was characterized by the absence of meconium excretion, abdominal distension in 444 (91.93%), delayed physiological weight gain against the background of nutritional insufficiency with the development of hypotrophy in 327 (67.70%) , vomiting of stagnant gastric and intestinal contents in 417 (86.34%). On the other hand, enterocolitis in 315 (65.22%), toxic megacolon in 16 (3.31%), and anemia of various degrees occurred in 241 (49.89%) patients among the complications that arose during the examination of patients with Hirschsprung's disease. According to the results of a comprehensive examination, the following extent of aganglionosis was established: rectal in 100 (20.70%), rectosigmoid in 192 (39.75%), subtotal in 150 (31.06%) and total in 41 (8.49%) patients. Concomitant malformations were found in 98 (20.29%) patients: renal malformations were diagnosed in 7 (1.45%) patients, concomitant heart malformations in 18 (3.73%) patients. Associated intraoperative findings were Meckel's diverticulum in 5 (1.03%) and congenital cyst of the right ovary in 1 (0.21%) patient. The clinical course was affected by concomitant malformations: incomplete bowel rotation in 10 (2.07%) and internal abdominal hernia in 2 (0.42%). The clinical manifestations and course of Hirschsprung's disease primarily depend on the presence of accompanying developmental defects, which may prevail during the examination due to vital disorders. In the clinical course of Hirschsprung's disease, it is necessary to distinguish between typical and atypical forms. Typical clinical symptoms were in 444 (91.93%), and atypical in 39 (8.07%).

Syndromic and single gene disorders associated with fetal megacystis (I): Megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS).

Fetal megacystis has been reported to be associated with chromosomal abnormalities, megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS), obstructive uropathy, prune belly syndrome, cloacal anomalies, limb-body wall complex, amniotic band syndrome, anorectal malformations, VACTERL association (vertebral anomalies, anal atresia, cardiac malformations, tracheo-esophageal fistula, renal anomalies and limb abnormalities) and fetal overgrowth syndrome such as Bechwith-Wiedemann syndrome and Sotos syndrome. This review provides an overview of syndromic and single gene disorders associated with fetal megacystis which is useful for genetic counseling at prenatal diagnosis of fetal megacystis.

Considerations and Outcomes for Adolescents and Young Adults With Cloacal Anomalies: A Scoping Review of Urologic, Colorectal, Gynecologic and Psychosocial Concerns.

The objective of this scoping review is to provide a summary of the current literature regarding adolescents and young adults with histories of cloacal anomalies. Preferred Reporting Items for Systematic Reviews and Meta-analysis Extension for Scoping Reviews were used. Data were categorized into four domains-urologic, colorectal, gynecologic/obstetric, and sexual/psychosocial. The current literature has poor study quality and mostly consists of retrospective studies of small cohorts with varying definitions of outcomes. Women with cloacal anomalies are at high risk for urologic dysfunction but can maintain kidney health and achieve social continence with medical and surgical management. Sexual function and adult healthcare transition are areas ripe for improved future research.

Outcomes From Colonic Pull-Through for Cloacal Exstrophy Differ by Colon Length: A Multi-Institutional Study.

BACKGROUND: Cloacal exstrophy (CE) represents a rare sub-group of anorectal malformations. Traditionally managed with a permanent colostomy, colonic pull-through (PT) has emerged to allow cleanliness without a life-long stoma. We sought to understand outcomes of PT in a large multi-center CE population. METHODS: We performed a retrospective study involving eleven pediatric hospitals. We gathered data on demographics, outcomes, and anatomical factors including colon length. Continuous variables were analyzed with Wilcoxon rank-sum tests and categorial variables with Fisher's exact tests. RESULTS: There were 98 patients, of which the majority (n = 70, 71.4 %) never underwent PT. There were no differences in exstrophy type, demographics, or associated anomalies. Median age at PT was 1.3 years (IQR 0.3-3.7). Of the cohort that continue to use their PT, the majority (n = 16, 69.6 %) are not clean. In total, 7.1 % (n = 7) of the cohort is clean with a PT, and only one patient is continent. Clean patients have a longer colon length than those who are not clean or opt for re-do ostomy (64.0 cm [IQR 46.0-82.0] vs 26.5 cm [IQR 11.6-41.2], p = 0.005). CONCLUSION: Overall, we demonstrate that most children born with CE will keep their stoma. Only a small percentage who elect to undergo colonic PT are clean for stool. Greater colon length correlates with success. This suggests that multiple factors, including colon length, are important when considering PT in a child with CE. LEVEL OF EVIDENCE: III.

A rare case of duplication of the descending colon in a pregnant woman: case report and literature review.

INTRODUCTION: Gastrointestinal duplications are uncommon congenital abnormalities that can occur anywhere throughout the intestinal tract. The small bowel is more interested than the large one. Duplications are schematically classified as spherical and tubular, respectively representing 80% and 20% of cases, with different relationships and communications with the native intestinal wall. Although typically diagnosed during infancy and early childhood, tubular colonic sub-type stays frequently hidden for several years until a complication occurs. CASE PRESENTATION: we report the case of a T-shaped tubular duplication in a 20-year-old woman at the 30th week of gestation, who underwent an urgent exploratory laparotomy for intestinal occlusion, treated with the resection of the aberrant large bowel. The patient was notable for a long history of constipation and chronic pain. Diagnostic possibilities were limited by the on-going pregnancy. CONCLUSION: Intestinal duplications are uncommon malformations, and, of these, the T-shaped subtype of the colon is among the rarest ones. In the adulthood, diagnosis is usually established in the operating room during urgent or even emergency surgery performed for abdominal complications. A duplication of the descending colon is extremely rare, and this is, to our knowledge, the only article describing a case found in advanced state of pregnancy.

Diagnostic value of the microcolon using ultrasonography in small bowel atresia.

BACKGROUND: Microcolon helps diagnose small bowel atresia (SBA) using contrast enema. However, there are no ultrasonography (US) microcolon criteria for diagnosing SBA. Therefore, this study aimed to evaluate colon accuracy and other characteristics for diagnosing SBA by US, using surgical or clinical information as the reference standard. METHODS: US was performed on 46 neonates aged ≤ 7 days old. In the study group (n = 15), neonates with SBA were confirmed following surgery. In the study group without SBA (n = 15), neonates with other gastrointestinal problems besides SBA were confirmed by surgical or clinical follow-up. Sixteen neonates without gastrointestinal problems were classified as the control group. The colonic diameter was measured, and colonic gas was sought and observed. Statistical analysis was performed to compare US parameters between the study group and other two groups. The optimal cut-off value of the colonic diameter for SBA diagnosis was obtained using receiver operating characteristic analysis. RESULTS: Colonic diameters (0.5 cm) in the study group (interquartile ranges [IQR], 0.5-0.6 cm) was significantly smaller than that in the group without SBA (0.9 cm; IQR, 0.8-1.2 cm) (P < 0.001) and in the control group (1.2 cm; IQR, 0.8-1.35 cm) (P < 0.001). Optimum cut-off value for diagnosing SBA was 0.65 cm (sensitivity, 90.3%; specificity, 86.7%; accuracy, 89.1%) for the colonic diameter. Combining microcolon and gas-negativity showed the best performance in SBA diagnosis using US, with increased accuracy (91.3%). CONCLUSION: A colon < 0.65 cm in diameter should be called a microcolon; combining US with gas-negativity is an essential diagnostic basis for SBA.

Exstrophy-Epispadias Complex With Isolated Ectopic Bowel Segment: A Case Series and Literature Review.

OBJECTIVE: To present a case series of the exstrophy-epispadias complex (EEC) with isolated ectopic bowel segment (IEBS) with the literature review, highlighting the clinical findings and treatments. MATERIALS AND METHODS: We present 3 cases of bladder exstrophy (BE) with IEBS in our institute and reviewed the literature in PubMed with the terms "("bladder exstrophy" OR "epispadias") AND ("visceral sequestration" OR "sequestered" OR "ectopic bowel")." RESULTS: There were 2 males and 1 female. The IEBS was detected by physical examination in 2 cases and by ultrasonography in another one. All cases were BE accompanying with lower abdominal mass which adhered to the bladder wall but was separated from the digestive system. All cases underwent the IEBS excision and BE repair simultaneously. Pathological result of IEBS suggested the histological structures of colon. There were totally 13 cases of EEC with IEBS reported in the literature, including 2 (15%) epispadias, 9 (69%) covered BE, 1 (8%) duplicate BE and 1 (8%) classic bladder exstrophy. Although their clinical manifestations were various, IEBS excision were safely conducted in all cases. CONCLUSION: EEC with IEBS is an extremely rare congenital malformation. Physical and imaging examinations are important for diagnoses. Surgical excision is safe and effective for managing IEBS.

The Diverse Phenotype of Intestinal Dysmotility Secondary to ACTG2-related Disorders.

BACKGROUND AND AIMS: The initial description of a heterozygous dominant ACTG2 variant in familial visceral myopathy was followed by the identification of additional variants in other forms of intestinal dysmotility disorders. we aimed to describe the diverse phenotype of this newly reported and rare disease. METHODS: Report of 4 new patients, and a systematic review of ACTG2-related disorders. we analyzed the population frequency and used in silico gene damaging predictions. Genotype-phenotype correlations were explored. RESULTS: One hundred three patients (52% girls), from 14 publications, were included. Twenty-eight unique variants were analyzed, all exceedingly rare, and 27 predicted to be highly damaging. The median Combined Annotation Dependent Depletion (CADD) score was 29.2 (Interquartile range 26.3-29.4). Most patients underwent abdominal surgery (66%), about half required intermittent bladder catheterization (48.5%), and more than half were parenteral nutrition (PN)-dependent (53%). One-quarter of the patients died (25.7%), and 6 required transplant (5.8%). Girls had a higher rate of microcolon (P  = 0.009), PN dependency (P = 0.003), and death/transplant (P = 0.029) compared with boys, and early disease onset (<2 years of age) was associated with megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS) features. There was no statistical association between disease characteristics and CADD scores. CONCLUSIONS: Damaging ACTG2 variants are rare, often associated with MMIHS phenotype, and overall have a wide phenotypic variation. Symptoms usually present in the perinatal period but can also appear at a later age. The course of the disease is marked by frequent need for surgical interventions, PN support, and mortality. Poor outcomes are more common among girls with ACTG2 variants.

Congenital Pouch Colon: Further Histopathological Perspectives.

Congenital pouch colon is an uncommon anomaly worldwide and is usually associated with anorectal malformations. Imperforate anus with a large air fluid level on the abdominal x ray suggests the diagnosis. Most cases are diagnosed in neonates and an early management limit complications. Few studies have documented the histopathological features of congenital pouch colon.We present two cases with varied associated anomalies (Case 1 with rectovesical fistula, Case 2 with Mayer Rokitansky Kuster Hauser syndrome) and their histopathological features. Immunohistochemistry for calretinin showed paucity of ganglion cells and intrinsic fibers with occasional punctate positivity. The c-Kit immunostain documented fewer interstitial cells of Cajal. Cystitis glandularis with intestinal metaplasia (Case 1) and an additional muscle layer (Case 2) are described.These novel histopathological features characterize the entity further and may be related to genesis of the pouch and its clinical manifestations.