Atresia of the colon

MR Imaging of the Fetal Gastrointestinal Anomalies

Fetal MR imaging has been shown to be a useful tool for the diagnosis of fetal gastro-intestinal pathologies. To recognize the various pathologies, it is, however, essential to know the normal MR imaging appearance of the fetal bowel at various gestational ages. By providing additional information to ultrasound in case of a fetal gastrointestinal anomaly, MR imaging helps to improve planning for the delivery, postnatal management, and improves parental counseling.

Maternal Preeclampsia and a Preterm Neonate With Small Bowel Stenosis, Volvulus, and Severe Intrauterine Growth Restriction

Preeclampsia is a human-specific hypertensive disorder of gestation. It is associated with short-term adverse effects in the fetus and long-term complications in the neonate, mainly due to disrupted blood flow during critical periods of intrauterine development. An ischemic event in the uterus can affect many systems of the fetus, including a small bowel involvement. We present a case of a preterm, small for gestational age neonate with severe intrauterine growth restriction, small bowel stenosis, and volvulus without malrotation, born to a mother with severe preeclampsia.

Colonic atresia and hirschsprung disease: a case report and review of the literature

BACKGROUND

Colon atresia is one of the rarest congenital anomalies of the gastrointestinal tract, with an incident range of between 1 in 10,000 and 66,000 live births. Type I colonic atresia affects only the mucosal layer of the intestine and spares the intestinal wall and mesentery. Hirschsprung Disease is a rare association of Colon atresia and is usually diagnosed as a complication of atresia treatment.

CASE PRESENTATION

This study reports a 14-h term white middle-eastern female infant with type I transverse colonic atresia complicated by the association of Hirschsprung disease and provides a brief literature review of the topic. She presented with poor feeding, weakness, and failure to pass meconium, and her abdominal X-ray showed complete distal bowel obstruction. The presence of Hirschsprung disease was realized after complications of atresia surgery. The infant underwent a total of three surgeries involving an end-to-end anastomosis of the atresia, colostomy formation following anastomosis leakage, and Hirschsprung surgery. The patient ultimately expired.

CONCLUSIONS

The association between colonic atresia and Hirschsprung disease poses a diagnostic and therapeutic challenge. Considering Hirschsprung disease as a possible association in colon atresia patients can facilitate proper decision-making in the course of treating colon atresia cases and achieving better outcomes.

Windsock or Cobra Head Sign: A Distinctive Imaging Sign to Differentiate Type 1 Colonic Atresia From Hirschsprung's Disease

Colonic atresia is a rare cause of congenital low-type intestinal obstruction in the neonatal age group and may present as a surgical emergency if not diagnosed early. Clinically, it can pose a diagnostic dilemma for Hirschsprung disease, which involves a different treatment strategy. Therefore, an early and accurate diagnosis is paramount from a management and prognosis perspective. The contrast enema plays a crucial role in the diagnosis of the disease. The "Windsock or Cobra head sign" on the contrast enema, typically seen only in type 1 colonic atresia, can help radiologists and surgeons identify this disease. We report a case of a two-day-old neonate, including a clinical feature of low-grade intestinal obstruction with distinctive imaging signs of type 1 colonic atresia, which can help make a definitive diagnosis.

Differences in the Outcome of Colonic Atresia with and without Abdominal Wall Defects

INTRODUCTION

 Colonic atresia (CA) is a very rare disease. Two entities of CA can be differentiated: primary CA and CA with abdominal wall defects (AWD). This study aimed to investigate the differences between these two entities, especially for long-term outcomes.

MATERIALS AND METHODS

 Data from the major health insurance company (AOK) were analyzed. Sixty-two patients with ICD-10 codes Q42.1-2 and Q42.8-9 (atresia of the colon and rectum) who underwent surgery within 10 days after their first admission between 2007 and 2016 were obtained.

RESULTS

 Twenty-nine patients had an AWD, and 33 patients had primary colonic atresia (PCA). Significant differences between patients with PCA and AWD were found regarding prematurity but not for other concomitant malformations. Ostomy was the initial therapy of choice for 87.9% (29/33) of patients with PCA and 65.5% (19/29) with AWD. Central venous access was significantly more often in patients with AWD. Overall, patients with CA have an excellent short-term outcome. The 1-year mortality was 3% (1/33) in PCA and 6.9% (2/29) in AWD. Delayed management did not lead to higher mortality. Higher number of admission days and higher hospital costs were related to gastrostomy and short bowel in the long term.

CONCLUSION

 The long-term outcome of CA is related to short bowel and need for initial gastrostomy but not related to AWD, prematurity, or associated anomalies.

Neonatal Gastrointestinal Emergencies: A Radiological Review

BACKGROUND

Abdominal emergencies in neonates require surgical management in almost all cases and complications may include bowel perforation, sepsis, shock, and even death. Radiological imaging has become a very important aid in the clinical setting as it shortens time to diagnosis.

OBJECTIVE

The objective of this review is to discuss the more prevalent neonatal gastrointestinal emergencies, review appropriate imaging options, and illustrate common radiological presentations of these entities.

CONCLUSION

Despite advancements in imaging techniques, it is important to keep in mind that neonates have a higher susceptibility to the adverse effects of ionizing radiation, and therefore radiography and ultrasonography remain the main diagnostic modalities for ruling out the diseases with the worst prognosis. Other modalities (fluoroscopy, computed tomography, and magnetic resonance imaging) may have limited use in very specific conditions. All providers in an emergency department should be familiar with the basic radiological findings that may indicate a gastrointestinal emergency, especially in health institutions that do not have 24-h radiologist coverage.

Neonatal and Pediatric Bowel Obstruction: Imaging Guidelines and Recommendations

Pediatric bowel obstructions are one of the most common surgical emergencies in children, and imaging plays a vital role in the evaluation and diagnosis. An evidence-based and practical imaging approach to diagnosing and localizing pediatric bowel obstructions is essential for optimal pediatric patient care. This article discusses an up-to-date practical diagnostic imaging algorithm for pediatric bowel obstructions and presents the imaging spectrum of pediatric bowel obstructions and their underlying causes.

Staged Repair Using Modified Bishop-Koop Procedure in Complicated Congenital Colonic Atresia in a Neonate

Colonic atresia (CA) is the rarest type of intestinal atresia and is defined as an obstruction in the large intestinal lumen. This is a rare case presentation of a four-day-old full-term female patient presented with signs and symptoms of intestinal obstruction. Investigation revealed that she had complicated CA located in the splenic flexure. Laparotomy and colostomy were done on the patient. About two months later, she was admitted for stoma closure, which was converted to modified Bishop-Koop stoma. Lastly, the patient underwent a successful stoma closure. Upon one month of follow-up, the patient's condition has markedly improved and the wound healed well without any complications.

Anorectal malformation, associated with colon atresia and intestinal malrotation, a case report

Introduction and importance

In this case report from Muhimbili National Hospital, Dar es salaam, Tanzania, we present the unexpected findings of anorectal malformation, colonic atresia, and intestinal malrotation in a 2-day old neonate. This combination is exceedingly rare, with only case reports published in the literature. We describe the challenges in diagnosis and offer our insights based on this experience and review of the literature.

Case presentation

Our patient was a male born at term, weighing 2600 g, diagnosed clinically with a high anorectal malformation. He was planned for colostomy, and we unexpectedly found a collapsed descending colon. Exploration revealed intestinal malrotation and three segments of type I colonic atresia from the mid transverse colon to the sigmoid colon in addition to the high anorectal malformation.

Clinical discussion

Creating a colostomy in a high anorectal malformation and failure to identify proximal intestinal atresia would result in potentially devastating consequences. Colonic atresia and anorectal malformation will both present as large bowel obstruction. In the extremely rare situation, when occurring in combination, the obvious clinical diagnosis of anorectal malformation will mask the clinical suspicion of the possibility of colonic atresia. Finding a distal bowel air bubble above the pubococcygeal line on an invertogram is useful in identifying proximal atresia preoperatively.

Conclusion

The current report emphasizes the importance of maintaining an awareness of possible associated colonic atresia in neonates with anorectal malformation. An invertogram and intraoperative finding of a collapsed descending colon should prompt evaluation for a proximal obstructing lesion.

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A newborn presented with an imperforate anus and no other apparent anomaly

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Findings of collapsed descending colon prompted explorative laparotomy.

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Intestinal malrotation, colonic atresia and anorectal malformation was found.

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Ladd's procedure and colostomy formation was done proximal to atretic segments.

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Finding collapsed colon prevented an unnecessary colostomy distal to the atresia.

Congenital multiple colonic atresias with intestinal malrotation: a case report

Background

Congenital intestinal atresia develops in 1 in 1500 to 20,000 births. Colonic atresia, which accounts for 1.8–15% of intestinal atresia cases, is accompanied by other gastrointestinal atresias such as small intestinal atresia, gastroschisis, imperforate anus, and intestinal malformation in 47–80%. Although a report shows that patients with multiple colonic atresias are 8.9% of those with colonic atresia.

Case presentation

A male infant did not have the first bowel movement within 36 h of birth and had abdominal distention/vomiting. Radiography showed significant dilation of the intestinal tract. A contrast enema examination at 3 days of age showed a microcolon and disruption in the descending colon. We performed an emergency decompressive loop enterostomy in the distended segment. At the age of 7 months, imaging from the stoma showed disruption of the contrast medium in the intestinal tract at the right lower abdomen, and the continuity of the intestinal tract was not clarified. Intestinal malrotation was found during the second surgery, and the enterostomy was located in the ileum proximal to Bauhin’s valve. Continuity of the intestinal serosal surface was maintained. However, multiple membranous obstructions (three atresias and one stenosis) were observed in the distal segment of the bowel, which was penetrated by intraluminal advancement of a urethral catheter. Therefore, he was diagnosed with multiple colonic atresias. The intestinal tract was longitudinally incised, and membranectomy and mucosal/lateral suture were performed.

Conclusions

It is important for neonates with intestinal atresia to evaluate and prepare for distal patency of the colon before radical anastomosis. In addition, anomalies associated with colon atresia should also be assessed.

Exome sequencing of family trios from the National Birth Defects Prevention Study: Tapping into a rich resource of genetic and environmental data

BACKGROUND

The National Birth Defects Prevention Study (NBDPS) is a multisite, population-based, case-control study of genetic and nongenetic risk factors for major structural birth defects. Eligible women had a pregnancy affected by a birth defect or a liveborn child without a birth defect between 1997 and 2011. They were invited to complete a telephone interview to collect pregnancy exposure data and were mailed buccal cell collection kits to collect specimens from themselves, their child (if living), and their child's father. Over 23,000 families representing more than 30 major structural birth defects provided DNA specimens.

METHODS

To evaluate their utility for exome sequencing (ES), specimens from 20 children with colonic atresia were studied. Evaluations were conducted on specimens collected using cytobrushes stored and transported in open versus closed packaging, on native genomic DNA (gDNA) versus whole genome amplified (WGA) products and on a library preparation protocol adapted to low amounts of DNA.

RESULTS

The DNA extracted from brushes in open packaging yielded higher quality sequence data than DNA from brushes in closed packaging. Quality metrics of sequenced gDNA were consistently higher than metrics from corresponding WGA products and were consistently high when using a low input protocol.

CONCLUSIONS

This proof-of-principle study established conditions under which ES can be applied to NBDPS specimens. Successful sequencing of exomes from well-characterized NBDPS families indicated that this unique collection can be used to investigate the roles of genetic variation and gene-environment interaction effects in birth defect etiologies, providing a valuable resource for birth defect researchers.

Colonic atresia in a newborn. Case Report

Introducción: la atresia colónica es el tipo menos común de atresia intestinal; sin embargo, debe sospecharse en pacientes con obstrucción intestinal parcial o completa, falla al pasar meconio, vómito y distensión abdominal. Se ha descrito un buen pronóstico en pacientes con tratamiento oportuno.Reporte de un caso: este artículo informa el caso de un paciente recién nacido que presenta vómito, distensión abdominal, falla al pasar el meconio y un rápido deterioro clínico progresivo. Durante la laparotomía exploratoria se encontró una atresia colónica que requirió una colostomía temporal debido a la discrepancia de los calibres proximal y distal. Posteriormente, se realizó la anastomosis colónica utilizando una colostomía protectora que finalmente se cerró. Este paciente tuvo una buena recuperación postoperatoria.Conclusión: la atresia colónica debe considerarse una causa importante de obstrucción intestinal distal en pacientes pediátricos y, por lo tanto, siempre debe sospecharse. También se recomienda descartar otras anomalías asociadas, así como realizar una biopsia rectal para la enfermedad de Hirschsprung para evitar complicaciones.

Demographic Study and Management of Colonic Atresia: Single-Center Experience with Review of Literature

Context and Aim

The aim of this study is to highlight the rarity of this disorder and its associated anomalies and our objective was to review our experience in the management of colonic atresia (CA) with respect to staged surgery versus one-step procedure for a better outcome of the disease.

Settings and Design

A randomized, controlled, single-center study conducted over a period of 4 years from October 2013 to 2017.

Subjects and Methods

Nine cases were operated for CA of which three underwent primary anastomosis and six underwent initial colostomy followed by definitive surgery. Age, sex, body weight, clinical presentation, type of atresia, site, time interval of operation, associated anomalies, initial procedure, postoperative complications, final procedure, biopsy, hospital stay, and outcome were noted.

Statistical Analysis Used

Microsoft Excel was used for statistical analysis.

Results

Out of 9 patients, 6 were males and 3 were females, 7 patients survived and 2 patients died (mortality 22.2%), of which one patient with primary anastomosis had leak and sepsis and one patient with primary anastomosis had associated Hirschsprung's disease (HD). Mean time gap for operation was 12.8 h and mean hospital stay was 3.5 days for initial colostomy and 21 days for primary anastomosis. Wound dehiscence occurred in 4 patients. Malrotation was found in 3 patients, HD in 2 patients, cardiac anomaly in 2, Meckel's diverticulum in 1, and cleft lip in 1 patient. Type IIIa atresia was found in in 6 patients, Type I in 2, and Type II in 1 patient. The most common site was transverse colon (n = 5).

Conclusion

Diagnosis and management of CA is a challenge. Early presentation and diagnosis should be prompt. Staged procedure with initial colostomy followed by definitive procedure is the preferred choice. Associated anomaly HD must be ruled out.

Colonic Atresia: Association with Other Anomalies

Background: Colonic atresia (CA) is a rare form of congenital intestinal atresia. Although CA may be isolated, it is more commonly reported in literature in association with other congenital anomalies.

Materials and Methods: This study is a review of prospectively collected data of all the patients with colonic atresia presented to our center (Ain Shams University) during 2008 to 2016.

Results: Twelve patients were enrolled in this study. The atresia was of type I in one case, type II in four cases, type IIIa in six cases, type IV in one case. These cases accounted for 4.9 % of intestinal atresias managed in our center during the same period. Five cases were isolated CA, while the other seven cases had associated abdominal congenital anomalies (exomphalos, Hirschsprung's disease, imperforate anus, closing gastroschisis, colonic duplication, and multiple small bowel atresia in two cases). The management in ten cases was by staged procedure with creation of a temporary stoma initially, while primary anastomosis was established in two cases. We had two cases with delayed presentations, one missed diagnosis, and three mortalities in this series.

Conclusions: The low incidence of CA may result in delay in the diagnosis and management. Hirschsprung's disease should be excluded in every case of colonic atresia. Early diagnosis and proper surgical management is essential for good prognosis.

Role of intraluminal bowel echogenicity on prenatal ultrasounds to determine the anatomical level of intestinal atresia

OBJECTIVE

To evaluate the correlation between different degrees of bowel intraluminal echogenicity showed by prenatal ultrasounds and the anatomic level of intestinal atresia.

METHODS

We report three cases of intestinal atresia at different intestinal levels verified during the neonatal surgery with specific ultrasonographic prenatal features. Intensity of sonolucency was analyzed using the image-processing program ImageJ for quantitative measurements based on the gray-scale intensity values.

RESULTS

A total of three cases are reported, a jejunal, an ileal and a colonic atresia. All cases showed intestinal dilatation. Both, jejunal and ileal atresia, showed two degrees of hypoechoic intestinal content, while colonic atresia showed hyperechogenic content dilated loop at prenatal ultrasound scan.

CONCLUSIONS

We propose the use of prenatal ultrasounds echogenicity of intestinal dilated loop fluid content to help in determining the level of obstruction in bowel atresia. These are initial results, to be confirmed by a multicentric research with more cases.

Histomorphological Features of Intestinal Atresia and its Clinical Correlation

INTRODUCTION

Intestinal atresia accounts for approximately one third of all cases of neonatal intestinal obstruction. There is controversy regarding pathogenesis of congenital atresia and stenosis of small bowel. Studies regarding clinical manifestations and specific histopathological features of neonatal intestinal atresia are scarce in Indian literature.

AIM

To understand the histomorphological features and thus suggest pathophysiology of cases with Intestinal Atresia.

MATERIALS AND METHODS

Out of 147 cases, of intestinal obstruction in newborn studied over a period of 5 years, 39 cases of intestinal atresia were found. Their histomorphological details with clinical manifestations were studied.

RESULTS

Type II was the commonest type of atresia. Associated anomalies noted were gastroschisis, volvulus, anal stenosis, microcolon, annular pancreas, meconium cyst and duplication cyst. Histological changes observed were ulceration, flattening, abnormal villous configuration, luminal obliteration, narrowing, haemangiomatous proliferation of blood vessels, fibrosis, haemorrhage, calcification, and mesenchymal condensation around the blood vessels. Gangrene and perforation has also noted in some cases.

CONCLUSION

An intrauterine intestinal ischemia due to vascular pathology followed by resorption of the bowel is the possible explanation for the development of intestinal atresia.

The Combination of Gastroschisis, Jejunal Atresia, and Colonic Atresia in a Newborn

We encountered a rare case of gastroschisis associated with jejunal atresia and colonic atresia. In our case, the jejunal atresia was not discovered for 27 days after the initial abdominal wall closure. The colonic atresia was not discovered for 48 days after initial repair of the gastroschisis secondary to the rarity of the disorder. Both types of atresia were repaired with primary hand-sewn anastomoses. Other than the prolonged parenteral nutrition and hyperbilirubinemia, our patient did very well throughout his hospital course. Based on our case presentation, small bowel atresia and colonic atresia must be considered in patients who undergo abdominal wall closure for gastroschisis with prolonged symptoms suggestive of bowel obstruction. Our case report also demonstrates primary enteric anastomosis as a safe, well-tolerated surgical option for patients with types of intestinal atresia.

Colonic atresia associated with annular pancreas: An extremely rare and previously unreported association

Colonic atresia is the rarest entity among the all intestinal atresias and may be associated with anterior abdominal wall defect, small intestinal atresia, Hirschsprung's disease, and other anomalies. Here, we are reporting a case of colonic atresia associated with annular pancreas, which has not been reported previously to the best of our knowledge.

Malrotation and intestinal atresias

This review encompasses four congenital conditions which present with symptoms of bowel obstruction in the neonatal period. The antenatal and postnatal features of malrotation, jejuno-ileal atresia, duodenal atresia and colonic atresia are discussed. Each condition is outlined including the classification, epidemiology, aetiology and presentation, and a summary of the surgical management is described.

Colonic atresia and anorectal malformation in a Haitian patient: a case study of rare diseases

INTRODUCTION

Colonic atresia and anorectal malformation are rare congenital anomalies individually. Few reports of the conditions combined in a single patient have been published in the literature. Neither colonic atresia, anorectal malformation or a combination of the disorders has previously been reported in the Haitian population.

CASE PRESENTATION

A 5-day-old female presented with feculent emesis, failure to pass stool since birth and an imperforate and stenotic anus. Exploratory laparotomy revealed colorectal atresia distal to a malformed cecum and a Wingspread low subtype anorectal malformation without any associated urogenital fistulae. Temporizing percutaneous ileal drainage was followed by second-stage anal perforation and dilation, ileal J-pouch and pull through.

DISCUSSION

This is the first reported case of colonic atresia, anorectal malformation or the combination of the disorders among the Haitian population and one of only a handful of such cases reported worldwide. Although vascular accidents in utero have been implicated as the etiology of colonic atresia, simultaneous presence of anorectal malformation suggests a multifactorial cause. Investigation for multisystem abnormalities is warranted. Two-staged operative correction is considered the best treatment; however, long-term postoperative outcomes are uncertain.

CONCLUSION

The coexistence of colonic atresia and anorectal malformation is a very rare occurrence and presents unique clinical and operative challenges. Investigation for additional congenital abnormalities is appropriate, and although two-stage operative correction is considered the best treatment, long-term outcomes are uncertain.

Rectal and sigmoid atresia: transanal approach

We report 2 patients with rectal and low sigmoid atresia operated on, respectively, at 6 and 3 months of age using the transanal approach, similar to the transanal technique for Hirschsprung disease, after exploratory laparotomy with colostomy at birth. There were no intraoperative or postoperative complications after a follow-up time of 2 years. After closure of the colostomy, both patients had no fecal incontinence. The transanal approach is a safe and effective technique in the management of rectal and sigmoid atresia.

Colon atresia and frontal encephalocele: a rare association

The association of colonic atresia with craniofacial anomalies has been well described and probably represents a malformative event that occurs in the early embryonal period. We present a case of an infant with colonic atresia and a frontal encephalocele and believe this to be a newly reported association. We review possible pathogenic mechanisms.

Proximal colonic atresia: is right hemicolectomy inevitable?

PURPOSE

Proximal colonic atresia often results in a marked discrepancy of the atretic ends presenting a technical challenge for restoration of bowel continuity. We review our series of colonic atresia patients with particular reference to the techniques for restoring bowel continuity.

METHODS

Case notes of all patients diagnosed with colonic atresia and admitted to our unit between 1997 and 2011 were reviewed.

RESULTS

There were 13 patients with a median gestational age of 39 weeks. Location of the atresia was ascending colon (n = 1), hepatic flexure (n = 9), proximal transverse colon (n = 2) and sigmoid colon (n = 1). The primary procedure was: primary anastomosis (n = 1), right hemicolectomy followed by ileo-colic anastomosis (n = 2), right hemicolectomy and stoma formation (n = 3). Six patients underwent stoma formation, of which five subsequently had a right hemicolectomy at a later procedure. In total, 10/12 patients required right hemicolectomy to facilitate restoration of bowel continuity. Median time to full feeds was 11 days (4-46). Median follow up time was 11 months (22 days-5.6 years).

CONCLUSION

A temporising stoma does not reduce the discrepancy in the calibre of the atretic ends in proximal colonic atresia. Right hemicolectomy and ileo-colic anastomosis should therefore be considered at the initial surgery.

Type 1 Bland Sutton colonic atresia complicated by fetalis hydrops in a premature neonate

Colonic atresia (CA) is an unusual cause of neonatal intestinal obstruction where a section of the colon has failed to form, leading to blockage or absence. A premature baby was delivered at 32 weeks of gestation via caesarian section following fetal distress. She was grossly oedematous and diagnosed with severe fetalis hydrops secondary to anaemia. She was resuscitated and stabilized. On the sixth day of life, the neonate's abdomen became severely distended with billous vomiting and failure to pass meconium. We suspected intestinal obstruction and performed an omnipaque enema which revealed dilated small bowel loops and a bowel atresia. Exploratory laparotomy confirmed a Type 1 Bland Sutton CA with mucosal web. An end colostomy was successfully performed and uneventful. In our case report, we describe a rare occurrence of postnatally diagnosed CA, complicated by fetalis hydrops and anaemia.

Management of isolated and associated colonic atresia

PURPOSE

Colonic atresia is a rare cause of congenital intestinal obstruction in the neonate. A review of the management and outcome of children with colonic atresia was performed.

METHODS

A retrospective analysis of the complete records of children treated for colonic atresia during the 30-year period.

RESULTS

A total of 14 newborns were treated. Seven infants suffered from an isolated colonic atresia (group 1). In the other seven infants (group 2), colonic atresia was either associated with additional intestinal atresias (n = 2), or gastroschisis (n = 5). Gestational age and birth weight were significantly lower in infants from group 2 compared to group 1 (40 ± 0.5 vs. 37 ± 1 weeks (P < 0.05); and 3,478 ± 208 vs. 2,626 ± 242 g (P < 0.01), respectively). The first surgical procedure was performed in all newborns within 24 h after birth. All but one infant from group 1 received primary colostomies at the level of colonic atresia, followed by end-to-side anastomoses. All but one infant from group 2 needed ileocoecal resection due to bowel necrosis. No child died in group 1, whereas three children died in group 2.

CONCLUSIONS

Isolated colonic atresia is amenable with a short hospital stay and an excellent outcome. In contrast, infants with colonic atresia associated with gastroschisis present a serious clinical challenge.

An alternative management option for colonic atresia preventing loss of the ileocecal valve

PURPOSE

Management of colonic atresia is contentious, with primary anastomosis having a notable risk of anastomotic leak. In addition, resection of the terminal ileum and ileocecal (i-c) valve is frequently performed, risking side effects such as diarrhea, vitamin B(12) deficiency, and gall stone formation.

METHODS

The hospital coding system was searched for all patients with a diagnosis of colonic atresia between July 2005 and July 2008. Four term neonates were managed by formation of an ileostomy, a "blow hole" stoma just proximal to the atresia, and a mucus fistula distal to the atresia.

RESULTS

Average time to full feeds was 7.5 days (range, 3-12 days), and average length of stay was 23 days (range, 13-47 days). Stoma management, problematic in 2 infants, was individualized by a specialist stoma nurse. Ileostomy output was refed into the mucus fistula. Complications included 3 episodes of prolapse of the blow hole stoma in infant 2. All of the infants returned to the operating theater at 1 to 3 months of age for restoration of bowel continuity and closure of the ileostomy. The atretic segment was resected, and an end-to-end anastomosis was performed. Recovery was straightforward in all cases.

CONCLUSION

A procedure that retains the i-c valve and most of the colon through creation of a blow hole stoma in the distended proximal colon with a diverting ileostomy and mucus fistula is described. The technique is recommended in selected infants as bowel length and anatomy can be preserved, despite the use of multiple stomas.

Atresia of the ascending colon: a rarity

Atresia of the colon is among the rare types of all gastrointestinal atresias. Ascending colon is the rarest site of all the colonic atresias. The authors report a case of a 4-day-old male baby who presented with the features of distal intestinal obstruction. At laparotomy type I atresia of the ascending colon, just distal to cecum, was found. Primary ceco-colic anastomosis along with a covering ileostomy was performed. Ileostomy was reversed 3 weeks later.

Individualized management of upper rectal atresia

BACKGROUND/PURPOSE

Congenital colonic atresia (CA) or stenosis is an infrequent cause of low intestinal obstruction in the neonate. Atresias can occur at any level, and the management of CA is determined by the atretic site and by the presence or absence of associated anomalies. We report our experience dealing with upper rectal atresia during a 5-year period.

METHODS

Between January 2004 and December 2008, 3 female newborns with upper rectal atresia with or without associated anomalies were treated. Modes of clinical presentation, methods of diagnosis, associated anomalies, alternative management techniques, and clinical outcome were retrospectively analyzed.

RESULTS

All 3 patients had progressive abdominal distension, bilious vomiting, and failure to pass meconium. Contrast enema showed an atresia at the upper rectum in 2 patients. At laparotomy, case 1 was found to have type III atresia of the upper rectum. Resection of the dilated portion of the proximal colon with end sigmoid colostomy was accomplished in the neonatal period followed by a transanal mucosectomy with takedown of the colostomy and a pull-through procedure at age 3 months. Case 3 had multiple jejunoileal atresias and an upper rectal atresia. The initial management was multiple resections of atretic bowel and anastomoses and an end sigmoid colostomy. The secondary procedure was a takedown of the colostomy and transanal mucosectomy with a pull-through procedure. Case 2 had type I upper rectal atresia in association with imperforate anus complicated by colon perforation during performance of a distal colostogram leading to a complicated and protracted clinical course. All the patients are currently well with voluntary bowel movements, and one has occasional soiling with follow-up of 9 months to 3 years.

CONCLUSIONS

Colon atresia, especially at the level of the upper rectum, is uncommon. Whether to proceed with an ostomy or to individualize the operative procedure according to the location of the atresia is still controversial. Transanal mucosectomy was a useful technique at the time of the definitive pull-through for the treatment of upper rectal atresia. In cases of upper CA associated with imperforate anus, delay in diagnosis and potential complications may result if the diagnosis of upper rectal atresia is missed.

Management of colonic atresia with primary resection and anastomosis

PURPOSE

Historically, the majority of patients with colonic atresia have been managed by ostomy creation at the time of initial operation; conversely, we have tended to treat the atresia with resection and anastomosis. The purpose of this study is to determine the rate of concomitant Hirschsprung's disease and to identify potential morbidity associated with primary repair.

METHODS

After IRB approval (#105825), charts of patients identified by ICD-9 code as having colonic atresia, who were admitted to our institution between 1993 and 2008 were, retrospectively, reviewed. Particular attention was paid to demographic data, comorbidities, operative therapy, and complications. Continuous variables were compared using an unpaired t test. A P value of <0.05 was considered significant.

RESULTS

Twelve newborns with colonic atresia were identified. Two babies were managed initially with ostomy, both of whom had gastroschisis; primary repair was performed on ten, with two undergoing simultaneous rectal biopsy. No anastomotic complications occurred and there were no mortalities. One patient experienced self-limited malabsorption symptoms after repair. No cases of Hirschsprung's disease were detected.

CONCLUSIONS

Uncomplicated colonic atresia can be managed by primary repair with little morbidity.

Congenital gastrointestinal anomalies in anorectal malformations: what relationship and management?

To date, no systematic review of gastrointestinal anomalies associated with anorectal malformations has been performed. We report the management of three challenging cases of neonates affected by congenital gastrointestinal and anorectal malformations and we review the pertinent published reports to disclose the incidence and outcome of this combination. In 3951 anorectal malformations, the incidence of digestive tract anomalies was approximately 15%. The association of multiple congenital gastrointestinal defects strongly increased the case complexity and worsened the outcome. Based on our study, the application of a rational and staged management plan provides easier diagnosis and treatment of complex cases. Moreover, keeping in mind the likely co-occurrence of anorectal and gastrointestinal anomalies could help avoid misdiagnosis and prevent life-threatening complications. Finally, the knowledge of this association and its successful management can help the multi-specialist team to become more confident in counselling, diagnosis and treatment.

Commonly encountered surgical problems in the fetus and neonate

Neonatal surgical care requires a current understanding of pre- and postnatal intervention for a myriad of congenital anomalies. This article includes an update of the recent information on commonly encountered fetal and neonatal surgical problems, highlighting specific areas of controversy and challenges in diagnosis. The authors hope that this article is useful for trainees and practitioners involved in any aspect of fetal and neonatal care.

Establishment of intestinal identity and epithelial-mesenchymal signaling by Cdx2

We demonstrate that conditional ablation of the homeobox transcription factor Cdx2 from early endoderm results in the replacement of the posterior intestinal epithelium with keratinocytes, a dramatic cell fate conversion caused by ectopic activation of the foregut/esophageal differentiation program. This anterior homeotic transformation of the intestine was first apparent in the early embryonic Cdx2-deficient gut by a caudal extension of the expression domains of several key foregut endoderm regulators. While the intestinal transcriptome was severely affected, Cdx2 deficiency only transiently modified selected posterior Hox genes and the primary enteric Hox code was maintained. Further, we demonstrate that Cdx2-directed intestinal cell fate adoption plays an important role in the establishment of normal epithelial-mesenchymal interactions, as multiple signaling pathways involved in this process were severely affected. We conclude that Cdx2 controls important aspects of intestinal identity and development, and that this function is largely independent of the enteric Hox code.

Gastroschisis with jejunal and colonic atresia, and isolated colonic atresia in dichorionic, diamniotic twins

Despite the increasing incidence of gastroschisis, the cause remains unknown. Genetic factors may contribute to bowel anomalies as demonstrated by cases of gastroschisis in twins and siblings, and other types of bowel anomalies in twins. Atresia of the colon represents one of the rarest causes of neonatal intestinal obstruction. We present the first case of dichorionic, diamniotic male twins in which there was gastroschisis with jejunal and colonic atresia in Twin A and isolated colonic atresia in Twin B.

Evaluation of the NK2 homeobox 1 gene (NKX2-1) as a Hirschsprung's disease locus

Hirschsprung's disease (HSCR, colonic aganglionosis) is an oligogenic entity that usually requires mutations in RET and other interacting loci. Decreased levels of RET expression may lead to the manifestation of HSCR. We previously showed that RET transcription was decreased due to alteration of the NKX2-1 binding site by two HSCR-associated RET promoter single nucleotide polymorphisms (SNPs). This prompted us to investigate whether DNA alterations in NKX2-1 could play a role in HSCR by affecting the RET-regulatory properties of the NKX2-1 protein. Our initial study on 86 Chinese HSCR patients revealed a Gly322Ser amino acid substitution in the NKX2-1 protein. In this study, we have examined 102 additional Chinese and 70 Caucasian patients and 194 Chinese and 60 Caucasian unselected, unrelated, subjects as controls. The relevance of the DNA changes detected in NKX2-1 by direct sequencing were evaluated using bioinformatics, reporter and binding-assays, mouse neurosphere culture, immunohistochemistry and immunofluorescence techniques. Met3Leu and Pro48Pro were identified in 2 Caucasian and 1 Chinese patients respectively. In vitro analysis showed that Met3Leu reduced the activity of the RET promoter by 100% in the presence of the wild-type or HSCR-associated RET promoter SNP alleles. The apparent binding affinity of the NKX2-1 mutated protein was not decreased. The Met3Leu mutation may affect the interaction of NKX2-1 with its protein partners. The absence of NKX2-1 expression in mouse but not in human gut suggests that the role of NKX2-1 in gut development differs between the two species. NKX2-1 mutations could contribute to HSCR by affecting RET expression through defective interactions with other transcription factors.

Evaluation of the thyroid transcription factor-1 gene (TITF1) as a Hirschsprung's disease locus

Hirschsprung's disease (HSCR, colonic aganglionosis) is an oligogenic entity that usually requires mutations in RET and other interacting loci. Decreased levels of RET expression may lead to the manifestation of HSCR. We previously showed that RET transcription was decreased due to alteration of the TITF1 binding site by two HSCR-associated RET promoter single nucleotide polymorphisms (SNPs). This prompted us to investigate whether DNA alterations in TITF1 could play a role in HSCR by affecting the RET-regulatory properties of the TITF1 protein. Our initial study on 86 Chinese HSCR patients revealed a Gly322Ser amino acid substitution in the TITF1protein. In this study we have examined an additional 102 Chinese and 70 Caucasian patients, and 194 Chinese and 60 Caucasian unselected, unrelated, subjects as controls. The relevance of the DNA changes detected in TITF1 by direct sequencing were evaluated using bioinformatics, reporter and binding-assays, mouse neurosphere culture, immunohistochemistry and immunofluorescence techniques. Met3Leu and Pro48Pro were identified in 2 Caucasian patients and 1 Chinese patient, respectively. In vitro analysis showed that Met3Leu reduced the activity of the RET promoter by 100% in the presence of the wild-type or HSCR-associated RET promoter SNP alleles. The apparent binding affinity of the TITF1 mutated protein was not decreased. The Met3Leu mutation may affect the interaction of TITF1 with its protein partners. The absence of Titf1 expression in mouse gut but not in human gut suggests that the role of TITF1 in gut development differs between the two species. TITF1 mutations could contribute to HSCR by affecting RET expression through defective interactions with other transcription factors.