Associations of anorectal malformations and related syndromes

1q21.1 Duplication Syndrome and Anorectal Malformations: A Literature Review and a New Case

BACKGROUND

Anorectal malformations (ARMs) are a common pediatric surgical problem with an incidence of 1:1500 to 1:5000 live births. The phenotypical spectrum extends from anal stenosis to imperforate anus with or without anal fistula to persistent cloaca. They can manifest as either non-syndromic or syndromic conditions. Various environmental and genetic risk factors have been elucidated. The widespread use of genetic screening tests for the investigation of developmental disorders increased the recognition of copy number variants (CNVs) of the 1q21.1 region. Duplications have also been associated with a multitude of congenital anomalies, such as heart disease, short stature, scoliosis, urogenital, and ARMs, and they have also been found in healthy individuals. The aim of this manuscript is to contribute to the definition of the phenotype associated with 1q21.1 duplications.

CASE PRESENTATION

The present case describes a male, referred to us for an ARM, in whom array-comparative genomic hybridization (array-CGH) identified 1q21.1 duplication inherited from his healthy mother. No other genetic test was performed on the patient.

CONCLUSIONS

We propose considering genetic evaluation and analysis in patients with only one congenital malformation in order to eventually make an early diagnosis and a better quality of treatments.

Anorectal malformations

Anorectal malformations (ARM) are rare congenital anomalies with an overall prevalence of 3.32 per 10,000 pregnancies. ARM describe a spectrum of anomalies of the anus and rectum ranging from a minimally displaced anal canal to a complete fusion of the anorectum, vagina and urethra with hypoplastic sphincter and pelvic floor muscle. Aberrant septation of the hindgut with anomalous cloacal membrane during weeks 6 to 9 of gestation form the developmental basis for a spectrum of anomalies defined as ARM. Although underlying specific syndromes and occasional familiar occurrence suggest genetic aetiology, most ARM are non-syndromic and their causal genetic mechanisms and non-genetic insults remain unclear. ARM is a clinical diagnosis, generally made early after birth via careful inspection of the perineum. Prenatal detection remains rare, and modern technical developments have added little to prenatal diagnostics. ARM is corrected surgically. Since its introduction in 1982, posterior sagittal anorectoplasty is the most common surgery for ARM reconstruction. Subsequent surgical adaptations focus on minimizing iatrogenic operative injury by limiting surgical invasiveness. They include laparoscopic procedures and shortening of incisions with confined dissection in open surgery. Although outcomes in patients with ARM have evolved throughout the past decades, there is urgent need for further improvements both in functional outcomes and quality of life. The importance of psychosocial experiences of affected patients is increasingly recognized. Continued research is necessary to improve prenatal detection, to elucidate genetic and epigenetic alterations and to refine optimal surgical procedures.

Anorectal malformations (ARM) and VACTERL association and severity of congenital heart diseases (CHD): Experience of 396 consecutive patients in a tertiary center

OBJECTIVE

Congenital heart diseases (CHD) are the most frequently associated anomalies with anorectal malformations (ARM). Nevertheless, many specific aspects of CHD in ARM patients have yet to be studied. The aims of this study were to evaluate the prevalence and distribution of CHD in neonates-infants with ARM, and to explore whether the severity of ARM, and the presence of VACTERL association, had an impact on CHD rate, severity, and timing at first cardiac surgery.

STUDY DESIGN

All consecutive newborn-infants with ARM managed in our tertiary center (January-1999; December-2021) were collected from a prospective database and retrospectively analyzed. Prevalence and distribution of CHD in ARM patients were assessed. Patients were divided into groups depending on ARM severity and presence of VACTERL association. Pairwise comparison for CHD prevalence, severity, and timing at first cardiac surgery was performed between groups.

RESULTS

Of 396 ARM patients identified, those with severe ARM showed a higher number of overall CHD compared to patients with non-severe ARM (36.7 % vs. 25.2 %, p = 0.032). VACTERL + patients had a significantly higher prevalence of CHD (73.4 % vs. 16.4 %; p <0.001) and major CHD (51.7 % vs. 26.9 %; p = 0.008) when compared with VACTERL-patients. Furthermore, VACTERL + patients underwent first cardiac surgery at a significantly younger age than VACTERL-patients (5.2 ± 15.2 months vs. 11.9 ± 6.3, p = 0.039).

CONCLUSIONS

Patients with severe ARM had a higher number of CHD compared to patients with non-severe ARM. VATERL + patients had significantly more CHD and more severe CHD than VACTERL-patients. Early screening for CHD is strongly recommended in all newborns diagnosed with ARM before surgery.

LEVEL OF EVIDENCE

III retrospective comparative study.

Expanding the clinical spectrum of Coffin-Siris syndrome with anorectal malformations: Case report and review of the literature

Anorectal malformations (ARMs) represent a wide spectrum of congenital anomalies of the anus and rectum, of which more than half are syndromic. Their etiology is highly heterogeneous and still poorly understood. We report a 4-year-old girl who initially presented with an isolated ARM, and subsequently developed a global developmental delay as part of an ARID1B-related Coffin-Siris syndrome (CSS). A co-occurrence of ARMs and CSS in an individual by chance is unexpected since both diseases are very rare. A review of the literature enabled us to identify 10 other individuals with both CSS and ARMs. Among the ten individuals reported in this study, 8 had a variant in ARID1A, 2 in ARID1B, and 1 in SMARCA4. This more frequent than expected association between CSS and ARM indicates that some ARMs are most likely part of the CSS spectrum, especially for ARID1A-related CSS.

Spatial transcriptomics reveals gene interactions and signaling pathway dynamics in rat embryos with anorectal malformation

Anorectal malformation (ARM) is a prevalent early pregnancy digestive tract anomaly. The intricate anatomy of the embryonic cloaca region makes it challenging for traditional high-throughput sequencing methods to capture location-specific information. Spatial transcriptomics was used to sequence libraries of frozen sections from embryonic rats at gestational days (GD) 14 to 16, covering both normal and ARM cases. Bioinformatics analyses and predictions were performed using methods such as WGCNA, GSEA, and PROGENy. Immunofluorescence staining was used to verify gene expression levels. Gene expression data was obtained with anatomical annotations of clusters, focusing on the cloaca region's location-specific traits. WGCNA revealed gene modules linked to normal and ARM cloacal anatomy development, with cooperation between modules on GD14 and GD15. Differential gene expression profiles and functional enrichment were presented. Notably, protein levels of Pcsk9, Hmgb2, and Sod1 were found to be downregulated in the GD15 ARM hindgut. The PROGENy algorithm predicted the activity and interplay of common signaling pathways in embryonic sections, highlighting their synergistic and complementary effects. A competing endogenous RNA (ceRNA) regulatory network was constructed from whole transcriptome data. Spatial transcriptomics provided location-specific cloaca region gene expression. Diverse bioinformatics analyses deepened our understanding of ARM's molecular interactions, guiding future research and providing insights into gene regulation in ARM development.

Obstructed Hemivagina and Renal Anomalies in Patients with and without Anorectal Malformations

STUDY OBJECTIVE

To compare the anatomic variation between patients with a diagnosis of an obstructed hemivagina with an anorectal malformation (ARM) and those without an ARM.

METHODS

This was a retrospective chart review conducted at a single tertiary children's hospital. Patients with an obstructed hemivagina seen from 2004 to 2019 were included.

RESULTS

We identified a total of 9 patients diagnosed with an obstructed hemivagina: 4 patients with a history of ARM and 5 patients without an ARM. Patients presented with obstructive symptoms between the ages of 11 and 20. Two-thirds of patients had a left-sided obstruction. All patients without an ARM had ipsilateral congenital anomalies of the kidney and urinary tract. Half the patients with a history of ARM had an ipsilateral renal anomaly, and the other half had a contralateral renal anomaly.

CONCLUSION

Obstructed hemivagina occurs in patients with a history of ARM. However, unlike patients with isolated obstructed hemivagina and ipsilateral renal anomaly (OHVIRA), patients with an ARM and an obstructed hemivagina can present with associated renal anomalies on either the ipsilateral or contralateral side. In our small case series, patients with a history of ARM had high septa and required more complex surgical management due to the inability to access the septum vaginally. Knowledge of renal anatomy and ureteral path is important because a hysterectomy may be needed to relieve the obstruction in patients with ARMs. A larger case series is needed to better characterize the spectrum of complex anomalies in patients with ARMs.

State of the Art Bowel Management for Pediatric Colorectal Problems: Anorectal Malformations

Up to 79% of patients with anorectal malformations (ARMs) experience constipation and/or soiling after a primary posterior sagittal anoplasty (PSARP) and are referred to a bowel management program. We aim to report the recent updates in evaluating and managing these patients as part of the manuscript series on the current bowel management protocols for patients with colorectal diseases (ARMs, Hirschsprung disease, functional constipation, and spinal anomalies). The unique anatomic features of ARM patients, such as maldeveloped sphincter complex, impaired anal sensation, and associated spine and sacrum anomalies, indicate their bowel management plan. The evaluation includes an examination under anesthesia and a contrast study to exclude anatomic causes of poor bowel function. The potential for bowel control is discussed with the families based on the ARM index calculated from the quality of the spine and sacrum. The bowel management options include laxatives, rectal enemas, transanal irrigations, and antegrade continence enemas. In ARM patients, stool softeners should be avoided as they can worsen soiling.

Does presence of a VACTERL anomaly predict an associated gynecologic anomaly in females with anorectal malformations?: A Pediatric Colorectal and Pelvic Learning Consortium Study

BACKGROUND

VACTERL association is defined by the presence of 3 or more anomalies in any of the following systems: vertebral, anorectal, cardiac, trachea-esophageal, renal, or limb. This study hypothesized that the presence of VACTERL association would correlate with an increased risk of gynecologic anomalies in patients with anorectal malformation (ARM).

METHODS

This study is a cross-sectional, retrospective analysis from the prospectively collected, multicenter registry of the Pediatric Colorectal and Pelvic Learning Consortium (PCPLC). The 834 female patients with ARM who were enrolled in the registry by January 1, 2020 were included in this study. The relationship of VACTERL association with presence of a gynecologic anomaly was evaluated with Fisher's exact test. The relationship of each VACTERL system with presence of a gynecologic anomaly was assessed in patients with cloaca, rectovestibular fistulas and rectoperineal fistulas. P-values reported were based on a 2-sided alternative and considered significant when less than 0.05.

RESULTS

834 patients with ARM underwent VACTERL screening and gynecologic evaluation with the three most common subtypes being cloaca (n = 215, 25.8%), rectovestibular fistula (n = 191, 22.9%) and rectoperineal fistula (n = 194, 23.3%). A total of 223 (26.7%) patients with ARM had gynecologic anomalies. VACTERL association was seen in 380 (45.6%) of patients with ARM. Gynecologic anomalies were present in 149 (39.1%) vs. 74 (16.3%) of subjects with vs. without VACTERL association (p < 0.001). VACTERL association did not significantly increase the risk of gynecologic anomaly in patients with cloaca and VACTERL (n = 88, 61.5%) vs. cloaca without VACTERL (n = 39, 54.2% p = 0.308). VACTERL association increased the risk of gynecologic anomalies in patients with rectoperineal fistulas (n = 7, 14.9% vs n = 9, 6.1% p = 0.014) and rectovestibular fistulas (n = 19, 31.1% vs. n = 13, 10.0% p<0.001). In patients with ARM who had a VACTERL association, when one of the associated anomalies was renal, there was an even higher risk of having an associated gynecologic anomaly (n = 138, 44.2% vs. n = 85, 16.3% p<0.001).

CONCLUSIONS

VACTERL association in patients with rectoperineal and rectovestibular fistulas correlates with an increased risk of gynecologic anomalies. The presence of VACTERL associated findings, especially renal, should prompt a thorough evaluation of the gynecologic system.

LEVEL OF EVIDENCE

III. Retrospective comparative study.

The Role of De Novo Variants in Formation of Human Anorectal Malformations

Anorectal malformations (ARM) represent a rare birth defect of the hindgut that occur in approximately 1 in 3000 live births. Around 60% of ARM occur with associated anomalies including defined genetic syndromes and associations with chromosomal aberrations. The etiology of ARM is heterogeneous, with the individual environmental or genetic risk factors remaining unknown for the majority of cases. The occurrence of familial ARM and previous epidemiologic analysis suggest autosomal dominant inheritance in a substantial subset of ARM patients. The implicated mortality and reduced fecundity in patients with ARM would lead to allele loss. However, mutational de novo events among the affected individuals could compensate for the evolutionary pressure. With the implementation of exome sequencing, array-based molecular karyotyping and family-based rare variant analyses, the technologies are available to identify the respective factors. This review discusses the identification of disease-causing variants among individuals with ARM. It highlights the role of mutational de novo events.

Anorectal Malformations and the Risk of Colorectal Cancer-Is Early Routine Endoscopic Screening Indicated?

INTRODUCTION

 Colorectal cancer (CRC) has been reported in early adulthood in patients with anorectal malformation (ARM), and therefore, the need of endoscopic controls has been discussed. The aim of this study was to assess the risk of CRC in patients with ARM.

MATERIALS AND METHODS

 This was a nationwide population-based study with data from Swedish national health care registers. All patients diagnosed with ARM born in Sweden between 1964 and 1999 were identified in the National Patient Register. The same group was followed up in the Swedish Cancer Register from birth to December 31, 2014, for occurrences of CRC. Five age- and gender-matched individuals randomly selected from the Medical Birth Register served as controls for each ARM patient born between 1973 and 1999.

RESULTS

 A total of 817 patients (474 males) with ARM were included and followed up from birth to the end of observational period. Time of follow-up ranged from 15 to 50 years (mean: 28 years). None of the patients was diagnosed with CRC during the observational period. One case of rectal cancer and one case of sigmoid cancer were detected among the 3,760 controls.

CONCLUSION

 In our study, the risk of CRC in early adulthood in patients with ARM is low. Our result does not support routine endoscopic follow-up for patients with ARM during the first decade of life.

Rare Association of Isolated Microphthalmia with Anorectal Malformation

Anorectal malformations (ARMs) have coexisting congenital anomalies. These can affect the overall prognosis. Anomalous craniofacial associations are less common. Recently, we managed two patients of ARM associated with unilateral microphthalmia, without any other major systemic anomalies. This was found to be a rare association on extensive literature search.

Characteristics of Anorectal Malformations in Children at the United States-Mexico Border: A 3-Year Study

BACKGROUND

Anorectal malformations (ARMs) are a group of congenital malformations affecting the lower gastrointestinal, urogenital, and/or gynecological systems. They occur in approximately 1 in 5000 live births, with a slight male predominance. ARMs can appear in isolation or in association with other anomalies. The literature contains little information about the characteristics of ARMs in United States Hispanic populations.

METHODS

An institutional review board-approved chart review was conducted in all patients with ARMs seen at a single institution in El Paso, Texas, from January 2012 to December 2015. Data regarding demographics, types of ARMs, associated syndromes, and long-term complications were recorded using the Krickenbeck classification system.

RESULTS

Of the 37 patients included in the study, 20 were boys and 17 were girls. The most common ARMs were rectoperineal fistula (46%), rectourethral fistula, and cloacal malformation. Constipation was the most common long-term complication, especially in patients with recto-perineal fistula.

CONCLUSION

Children in the Borderland community may have a higher percentage of recto-perineal fistula than previously reported. Postoperative complications in Hispanic children with ARM were comparable to those reported in other populations.

Neural tube defects in four Shetland sheepdog puppies: clinical characterisation and computed tomography investigation

BACKGROUND

Here, we report on the occurrence of neural tube defects (NTDs) in four related Shetland sheepdog puppies. NTDs present as a range of congenital malformations affecting the spine, skull and associated structures. Despite the severity of these malformations and their relatively high prevalence in humans, the aetiology is not well understood. It is even less well characterised in veterinary medicine.

CASE REPORT

Affected puppies were investigated using computed tomography (CT) and then necropsy. CT identified a range of brain and spine abnormalities in the affected animals, including caudal anencephaly, encephalocele, spina bifida and malformed vertebrae. Other observed abnormalities in these puppies, including cranioschisis, atresia ani and hydrocephalus, may be secondary to, or associated with, the primary NTDs identified.

CONCLUSION

This case report describes multiple related cases of NTDs in an Australian cohort of dogs. This study also highlights the potential of advanced imaging techniques in identifying congenital anomalies in stillborn and neonatal puppies. Further research is required to investigate the aetiology of NTDs in this group of affected Shetland sheepdogs.

Imperforate Anus and Rectourethral Fistula in a Female

Anorectal malformations (ARM) are complex, heterogeneous disorders and in females the most common anomaly is imperforate anus with a rectovestibular fistula. We describe a malformation not previously encountered in the literature: imperforate anus associated with a normal urethra, normal vagina, but with a recto urethral fistula. Rectourethral fistula in a female is an extremely rare ARM. Precise workup is required to clarify the anatomy for operative planning.

MSX2 and BCL2 expressions in the development of anorectal malformations in ethylenethiourea-induced rat embryos

BACKGROUND

This study aimed to determine Msh homeobox 2 (MSX2) and B cell lymphoma-2 (BCL2) expression patterns during anorectal development in anorectal malformations (ARM) and normal rat embryos, with the goals of determining the role of MSX2 and BCL2 in ARM pathogenesis.

METHODS

ARM was induced in rat embryos with ethylenethiourea administered to dams on gestational day 10 (GD10). Embryos were harvested by cesarean deliveries from GD14 to GD16. MSX2 and BCL2 expression was evaluated via immunohistochemical staining, immunofluorescence, western blotting and quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

Immunohistochemical staining of ARM embryos revealed that MSX2 was mainly expressed in the epithelium of the hindgut and urorectal septum (URS) on GD14. On GD15 and GD16, MSX2-immunolabeled cells were noted in the epithelium of the rectum, fistula and URS. However, in normal embryos, faint immunopositivity for MSX2 was demonstrated in the epithelium of the rectum and URS from GD14 to GD16. As for BCL2, in normal embryos, BCL2-immunopositive cells were extensively expressed in the epithelium of the hindgut and URS on GD14 and GD15. In ARM embryos, weak immunopositivity for BCL2 was detected in the epithelium of hindgut and URS on GD14 and GD15. Immunofluorescence revealed that MSX2 and BCL2 colocalized in the hindgut. In ARM embryos, we observed more MSX2-positive than BCL2-positive cells on GD14; the normal embryos had the opposite pattern. Analyses by western blot and qRT-PCR showed that MSX2 protein and mRNA expression was significantly increased in ARM embryos compared with the normal embryos on GD15 and GD16 (p < 0.05). However, BCL2 protein and mRNA expression was significantly decreased in ARM embryos compared with the normal embryos on GD14 (p < 0.05). The MSX2/BCL2 ratio of protein and mRNA expression level in the ARM group was the highest on GD15.

CONCLUSION

These results indicate that upregulation of MSX2 and downregulation of BCL2 during cloacal development into the rectum and urethra might be related to the ARM development, and MSX2 promoted apoptosis through reduction of BCL2 expression during the development of anorectal development in ARM.

A missense mutation in EBF2 was segregated with imperforate anus in a family across three generations

The etiology of imperforate anus, a major phenotype of anorectal malformation (ARM), is still unknown and not a single gene has been reported to be associated with it. We studied a Korean family with six affected members with imperforate anus across three generations by whole exome sequencing and identified a missense mutation in the EBF2 gene (c.215C > T; p.Ala72Val). This mutation is completely segregated with the disease phenotype in the family and is evolutionarily highly conserved among diverse vertebrates. Also, this mutation was predicted to be functionally damaging. These results support that missense mutation in the EBF2 c.215C > T (p.Ala72Val) is very likely to contribute to the pathogenesis of ARM in this family.

A review of genetic factors contributing to the etiopathogenesis of anorectal malformations

BACKGROUND

Anorectal malformation (ARM) is a common congenital anomaly with a wide clinical spectrum. Recently, many genetic and molecular studies have been conducted worldwide highlighting the contribution of genetic factors in its etiology. We summarize the current literature on such genetic factors.

MATERIALS AND METHODS

Literature search was done using different combinations of terms related to genetics in anorectal malformations. From 2012 to June 2017, articles published in the English literature and studies conducted on human population were included.

OBSERVATIONS AND RESULTS

A paradigm shift was observed from the earlier studies concentrating on genetic aberrations in specific pathways to genome wide arrays exploring single nucleotide polymorphisms (SNPs) and copy number variations (CNVs) in ARM patients. Rare CNVs (including 79 genes) and SNPs have been found to genetically contribute to ARM. Out of disrupted 79 genes one such putative gene is DKK4. Down regulation of CDX-1 gene has also been implicated in isolated ARM patients. In syndromic ARM de novo microdeletion at 17q12 and a few others have been identified.

CONCLUSION

Major genetic aberrations proposed in the pathogenesis of ARM affect members of the Wnt, Hox (homebox) genes, Sonic hedgehog (Shh) and Gli2, Bmp4, Fgf and CDX1 signalling pathways; probable targets of future molecular gene therapy.

Improving the rigour of VACTERL screening for neonates with anorectal malformations

PURPOSE

Screening investigations for the vertebral, anorectal, cardiac, tracheo-oesophageal, renal and limb (VACTERL) association form an important part of the management of neonates with anorectal malformations (ARMs). We developed a proforma to define investigations and indications for referral. The aim of the current study was to determine if the proforma could improve screening rigour.

METHODS

Four centres performed a 3-year retrospective audit of neonates with ARM. Following introduction of a proforma, the same data were collected prospectively for consecutive neonates over a further 2 years. The appropriate investigation of each component of the VACTERL association and the corresponding referral required for each abnormal result were defined. The proportion of patients undergoing appropriate investigation and referral was compared against these standards. An audit standard of 90% was set for each criteria.

RESULTS

Prior to implementation of the proforma, 86 patients were audited, with a further 69 patients after. The audit standard was met in 7 criteria before introduction of the proforma in comparison to 10 criteria afterwards.

CONCLUSION

The completeness of VACTERL screening and its documentation improved following introduction of the proforma. Performance remains imperfect. Review of specific criteria (such as definition of vertebral body screening) will help address this.

Syndromic anorectal malformation associated with Holt-Oram syndrome, microcephaly, and bilateral corneal opacity: a case report

BACKGROUND

The occurrence of an anorectal malformation with Holt-Oram syndrome, microcephaly, and bilateral corneal opacity is rare and to the best of our knowledge has not previously been reported in the literature. Hence, there is a need to document our experience in this case and learn as much as possible from it.

CASE PRESENTATION

We present the case of a Nigerian female neonate with a postnatal diagnosis of syndromic anorectal malformation associated with Holt-Oram syndrome, microcephaly, and bilateral corneal opacity. The infant had successful staged correction of her anorectal malformation but developed a metastatic Wilms' tumor and died before other corrective procedures could be instituted.

CONCLUSIONS

An anorectal malformation is here reported to occur with Holt-Oram syndrome, an association that has not been reported previously. To enhance the prognosis and quality of life of children with syndromic anorectal malformation, prenatal ultrasound monitoring of high-risk pregnancies and expertise in prenatal detection of congenital anomalies are invaluable in antenatal care.

Outcome in anorectal malformation type rectovesical fistula: a nationwide cohort study in The Netherlands

PURPOSE

Outcomes of patients with an ARM-type rectovesical fistula are scarcely reported in medical literature. This study evaluates associated congenital anomalies and long-term colorectal and urological outcome in this group of ARM-patients.

METHODS

A retrospective Dutch cohort study on patients treated between 1983 and 2014 was performed. Associated congenital anomalies were documented, and colorectal and urological outcome recorded at five and ten years of follow-up.

RESULTS

Eighteen patients were included, with a mean follow-up of 10.8years. Associated congenital anomalies were observed in 89% of the patients, 61% considered a VACTERL-association. Total sacral agenesis was present in 17% of our patients. At five and ten years follow-up voluntary bowel movements were described in 80% and 50%, constipation in 80% and 87%, and soiling in 42% and 63% of the patients, respectively. Bowel management was needed in 90% and one patient had a definitive colostomy. PSARP was the surgical reconstructive procedure in 83%. Urological outcome showed 14 patients (81%) to be continent. No kidney transplantations were needed.

CONCLUSION

In our national cohort of ARM-patients type rectovesical fistula that included a significant proportion of patients with major sacral anomalies, the vast majority remained reliant on bowel management to be clean after ten years follow-up, despite "modern" PSARP-repair. Continence for urine is achieved in the majority of patients, and end-stage kidney failure is rare.

[Risk factors for congenital anal atresia]

OBJECTIVE

To investigate the risk factors for the development of congenital anal atresia in neonates.

METHODS

A total of 70 neonates who were admitted to 17 hospitals in Foshan, China from January 2011 to December 2014 were enrolled as case group, and another 70 neonates who were hospitalized during the same period and had no anal atresia or other severe deformities were enrolled as control group. Univariate and multivariate logistic regression analyses were used to investigate the risk factors for the development of congenital anal atresia.

RESULTS

The univariate analysis revealed that the age of mothers, presence of oral administration of folic acid, infection during early pregnancy, and polyhydramnios, and sex of neonates showed significant differences between the case and control groups (P<0.05). The multivariate logistic regression analysis revealed that infection during early pregnancy (OR=18.776) and male neonates (OR=9.304) were risk factors for congenital anal atresia, and oral administration of folic acid during early pregnancy was the protective factor (OR=0.086).

CONCLUSIONS

Infection during early pregnancy is the risk factor for congenital anal atresia, and male neonates are more likely to develop congenital anal atresia than female neonates. Supplementation of folic acid during early pregnancy can reduce the risk of congenital anal atresia.

Birth outcomes of patients with isolated anorectal malformations: A population-based case-control study

In most patients affected by isolated anorectal malformation (IARM) the etiology is largely unknown. Thus, the aim of our project was to analyze possible risk factors for IARM. In the first step, birth outcomes of cases with IARM were analyzed on the basis of maternal socio-demographic variables, and these data are presented in this paper. Gestational age at delivery, birthweight, preterm birth, low birthweight and small for gestational age of cases with IARM were evaluated in the function of maternal age, birth/pregnancy order, marital and employment status of mothers in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. The study samples included 231 live-born cases with IARM, 361 matched and 38 151 population controls without any defect. IARMs are more frequent in males, twins and newborn infants with low birthweight and small-for-gestational-age, the latter being the consequence of intrauterine growth restriction. In addition, mothers of cases were younger but with higher birth order, and had lower socio-economic status. These maternal variables are characteristic for the gypsy population in Hungary. The higher proportion of gypsy women among the mothers of cases with IARM was confirmed during the home visits of the study. Male sex and intrauterine growth restriction of cases, in addition to low socioeconomic status and gypsy origin of mothers may have a role in the risk of IARMs.

Anorectal malformation: the etiological factors

Anorectal malformation (ARM) is a congenital anomaly commonly encountered in pediatric surgery practice. Although surgical procedures correct the anatomical anomalies, the post-operative bowel function is not universally satisfactory. The etiology of ARM remains unclear. In this review, we summarize the current understanding of the genetic and epigenetic factors contributing to the pathogenesis of ARM, based on published animal models, human genetics and epidemiological researches. Appreciation of these factors may be helpful in the management of ARM in the future.

Unusual presentation of a rectovestibular fistula as gastrointestinal hemorrhage in a postmenopausal woman

Background. Anorectal malformations (ARMs) are extremely rare and are usually identified neonatally. It is unusual for these cases to present in the postmenopausal period. This case report describes a postmenopausal patient with ARM and rectovaginal hemorrhage. Case. An 86-year-old, gravida 11, para 9, presented to the emergency department complaining of profuse postmenopausal vaginal bleeding. Her gynecologic history was significant only for an unclear history of an anal abnormality that was noted at birth. Speculum examination revealed profuse rectal bleeding from a rectovestibular fistula exterior to her hymenal ring. Colonoscopic examination revealed severe diverticular disease. Conclusion. This patient was born with an imperforate anus which resolved as rectovestibular fistula and ectopic anus. This case presents a rare clinical circumstance which integrates the fields of obstetrics, gynecology, gastroenterology, and embryology alike.