The Currarino triad: complex of anorectal malformation,sacral bony abnormality,and presacral mass

The Currarino triad is a unique complex of congenital caudal anomalies including anorectal malformation, sacral bony abnormality, and presacral mass. The usual symptomatology is constipation due to anorectal stenosis. Contrast enema and computed tomographic myelography are the imaging modalities of choice for diagnostic confirmation and clarification of the anomalies. The clinical features, unique radiologic appearance, and importance of a correct diagnosis of the Currarino triad are reviewed.     

Abnormal anatomy of the lumbosacral region imaged by magnetic resonance in children with anorectal malformations.

OBJECTIVE: To investigate the frequency of lumbosacral anomalies, the association with urogenital abnormalities, and the correlation with defaecation pattern by magnetic resonance imaging (MRI). METHODS: A prospective analysis was performed of routine MRI in patients with anorectal malformations. Between 1990 and 1994, MRI was performed in 43 such patients: 31 boys and 12 girls. Twenty four had a high anorectal malformation, 16 had a low anorectal malformation, and three had Currarino''s triad. MRI was performed before reconstruction in 26, and postoperatively in 17. Urogenital anomalies were found in 21. RESULTS: Abnormalities of the spinal cord and spine were found with MRI in 20 patients (46.5%); caudal regression syndrome in 10, tethered cord in two, a combination of both in three, and other spinal anomalies in five. These anomalies were found in 30% of the patients with low anorectal malformations, and in 50% with high anorectal malformations. In patients with urogenital malformations, MRI more often showed spinal anomalies (13/21, 62%) than in patients without (7/22, 32%). In high anorectal malformations, defaecation was more often a problem in patients with spinal anomalies (12/15, 80%) than in patients without (2/8, 25%). CONCLUSIONS: Spinal anomalies in the lumbosacral region were found with MRI in 46.5% of patients with anorectal malformations. Since presence of these anomalies seems to be related to clinical outcome, MRI should be performed routinely in all such patients.     

先天性无肛畸形儿MR成像及其与排便功能关系研究

目的评估先天性肛门直肠畸形儿（anorectal malformations，ARM）尾端发育情况及横纹肌复合体（sphincter muscle complex，SMC）发育状态与排便功能的关系。方法39例ARM，男28例，女11例，应用不同序列体部相控阵列线圈或头部线圈MRI显示ARM直肠闭锁水平、骶尾椎、骶髓、泌尿生殖系的发育情况，并对SMC从多个层面进行定量分析，评估其发育状态与临床评分和肛门功能客观检查的关系。结果39例患儿中，MRI T1WI、T2WI扫描判断畸形水平的正确诊断率为100％，T2WI扫描瘘管检出率为96．9％。骶尾椎和骶髓的异常占41．0％，泌尿生殖系统畸形占20．5％。当耻骨直肠肌宽度的相对值PRWR〈0．18，外括约肌宽度的相对值EASWR〈0．15时，71．4％的ARM术后出现肛门失禁。当PRWR〉0．18，EASWR〉0．15时，91．3％的ARM术后排便功能好。结论MR检查能清楚地显示ARM类型、闭锁水平、SMC发育状态、脊柱脊髓及泌尿生殖系统存在的伴发畸形，从MR影像中找到了评价SMC的定量指标。     

Abnormal anatomy of the lumbosacral region imaged by magnetic resonance in children with anorectal malformations

OBJECTIVE: To investigate the frequency of lumbosacral anomalies, the association with urogenital abnormalities, and the correlation with defaecation pattern by magnetic resonance imaging (MRI). METHODS: A prospective analysis was performed of routine MRI in patients with anorectal malformations. Between 1990 and 1994, MRI was performed in 43 such patients: 31 boys and 12 girls. Twenty four had a high anorectal malformation, 16 had a low anorectal malformation, and three had Currarino's triad. MRI was performed before reconstruction in 26, and postoperatively in 17. Urogenital anomalies were found in 21. RESULTS: Abnormalities of the spinal cord and spine were found with MRI in 20 patients (46.5%); caudal regression syndrome in 10, tethered cord in two, a combination of both in three, and other spinal anomalies in five. These anomalies were found in 30% of the patients with low anorectal malformations, and in 50% with high anorectal malformations. In patients with urogenital malformations, MRI more often showed spinal anomalies (13/21, 62%) than in patients without (7/22, 32%). In high anorectal malformations, defaecation was more often a problem in patients with spinal anomalies (12/15, 80%) than in patients without (2/8, 25%). CONCLUSIONS: Spinal anomalies in the lumbosacral region were found with MRI in 46.5% of patients with anorectal malformations. Since presence of these anomalies seems to be related to clinical outcome, MRI should be performed routinely in all such patients.     

DELETION MAPPING OF CRITICAL REGION FOR HYPOSPADIAS, PENOSCROTAL TRANSPOSITION AND IMPERFORATE ANUS ON HUMAN CHROMOSOME 13

BACKGROUND: The 13q-deletion syndrome causes human congenital birth defects due to the loss of regions of one long arm of human chromosome 13. A distal critical region for severe genitourinary and anorectal birth defects in the region of 13q32.2-34 has been suggested; we sought to narrow this critical region. METHODS: From patients with karyotypes revealing haploinsufficiency for distal chromosome 13q and their parents, peripheral blood was obtained and lymphocytes were immortalized for DNA isolation. Genetic and molecular cytogenetic methods were used to map deletions. Patient and parental samples were genotyped with a panel of 20 microsatellite markers spanning 13q31.3 qter and deletions identified by loss of heterozygosity. Deletions were also mapped using a panel of 35 BAC clones from the same region as probes for fluorescence in-situ hybridization on patient lymphoblastoid metaphase preparations. The data were synthesized and a deletion map defining the critical region was generated. RESULTS: Eight patients with known deletions around 13q32qter and their parents were analyzed, and categorized into three groups: three patients with anorectal and genitourinary anomalies (hypospadias, penoscrotal transposition), four male patients without anorectal and genitourinary anomalies, and one XY patient with ambiguous genitalia without anorectal anomalies. We mapped the critical region for anorectal and genitourinary anomalies to a approximately 9.5-Mb interval of 13q33.3-q34 delineated by markers D13S280-D13S285; this spans approximately 8% of the chromosome and contains 20 annotated genes CONCLUSION: The critical region of chromosome 13q mediating genitourinary/anorectal anomalies has been mapped, and will be narrowed by additional patients and further mapping. Identification of the gene(s) mediating these syndromic genitourinary defects should further our knowledge of molecular mediators of non-syndromic hypospadias, penoscrotal transposition and anorectal malformations.     

Management and outcome of low anorectal malformations

Low anorectal malformation comprises about half of all anorectal anomalies. Most of the literature concerning management of anorectal anomalies is centred around the treatment and outcome of high anomalies. The management of low anomalies has been considered significantly less challenging than high anomalies. Also, the outcome of low anomalies has traditionally been considered good. However, recent more critical long-term follow-up reports show a different picture. Many patients with low anomalies suffer from long-term anorectal functional problems, especially constipation but also soiling that occurs in a significant percentage of patients. In this review, we compile the recent views on the diagnosis, surgical treatment and outcome of low anorectal anomalies. We also present an algorithm for the management of these anomalies. The emphasis on the surgical management of low anorectal anomalies is to use as minimally invasive operative methods as possible and preserve the native mechanisms of continence that usually are much better preserved than in more severe high anomalies.     

中国人直肠肛门畸形1262例分析

目的 了解中国人直肠肛门畸形基本状况及合并其他畸形的情况,为临床治疗提供参考资料。方法 １９８７￣１９９２年中国出生缺陷监测网以医院为基础在全国对孕２８周至产后７天的围产儿进行监测,对监测出的１２６２例直肠肛门畸形患儿进行流行病学分析。结果 中国人直肠肛门畸形的发病率为２．８１／万,全国各地发生率无显著差异,且发生率呈下降趋势。单发直肠肛门畸形５３１例,多发７３１例,其中尸解３０３例,直肠肛门畸形     

Bowel function after surgery for anorectal malformations in patients with tethered spinal cord

Tethered spinal cord (TC) is an anomaly frequently recognized in association with anorectal malformations (ARM). However, the influence of TC on bowel function in children with ARM remains unknown. Furthermore, there are few studies that have assessed anorectal function in children with ARM and TC. The aim of this study was to evaluate anorectal function in ARM patients with TC using clinical assessment and anorectal manometry. Among 258 patients with ARM, this retrospective investigation included 35 patients who underwent spinal magnetic resonance imaging (MRI) after surgery for ARM. The patients were divided into two groups based on the presence or absence of TC, and bowel function was assessed by Kelly’s clinical score and anorectal manometry. Tethered cord was found in nine of the 35 patients (26%) with ARM. Of the ARM patients, TC was noted in four of 11 (36%) with high type anomalies, one of 8 (13%) with intermediate type anomalies, two of 14 (14%) with low type anomalies, and two of two patients (100%) with cloacal anomalies. Kelly’s clinical score did not significantly differ between the two groups. However, two of the nine patients with TC had poor bowel function (Kelly’s score; 2–0 points). On the contrary, patients without TC did not have poor bowel function. Anorectal manometry did not show a significant difference between patients with and without TC. However, the two patients with TC who had poor bowel function by Kelly’s score had low anal resting pressure, which was essential for achieving fecal continence. In conclusion, the present study showed that tethered cord was more frequently found in patients with more severe anorectal anomalies. Patients with TC were more likely to have poor bowel function, but this did not reach statistical significance. Presented at the 14th International Paediatric Colorectal Club, York, UK, 14–16 July 2007.     

Low anorectal anomalies: a critical appraisal

Retrospective review of 38 consecutive children with low anorectal anomalies encountered over a 7-year period was undertaken. Detailed follow-up data were available on 32 patients. Only 15 (47%) were diagnosed in the neonatal period, 6 being diagnosed after 6 months of age. Three patients had a colostomy performed prior to referral. Surgical correction was mainly by dilatation (7), cutback (8), or anoplasty (13). Associated anomalies occurred in 35% of patients; in addition, 19 (59%) had vesicoureteric reflux (VUR) with a total of 27 refluxing renal units. Three patients have undergone reimplantation of ureters. Intractable constipation was a major problem in 25% of patients and was unrelated to the time of diagnosis or treatment. The results showed that conventional management of low anorectal anomalies is followed by a substantial incidence of bowel problems. Due to the high incidence of associated VUR, all patients with anorectal anomalies should have a detailed urological assessment, including a micturating cystourethrogram. Offprint requests to: E. M. Kiely     

SD-mice--an animal model for complex anorectal malformations

Animal models for morphological investigations of anorectal malformations are barely known to pediatric surgeons. In this study the morphological characteristics of a spontaneous mutation of the house mouse, the so-called SD-mouse, are described. The semidominant gene SD exerts its influence on the anorectum, the urogenital system and the axial skeleton. Many heterozygous (SD/+) and all homozygous (SD/SD) animals die shortly after birth due to their malformations. Surviving heterozygotes, identified by their short and deformed tails, may be used for breeding purposes. According to Mendel's laws, mating of such heterozygous yields 75% more or less malformed animals which may be used for morphological investigations. The morphological features of these animals were investigated in 61 neonatal SD-mice (33 SD/SD, 28 SD/+) and in 10 normal controls by microdissection and in 49 animals (25 SD/SD, 20 SD/+ and four normal controls) by serial sections. Of these, all homozygous and 10 heterozygous SD mice had anorectal malformations. The spectrum of these malformations is wide: very complex malformations in SD/SD mice and high anorectal malformations in SD/+ mice. These are comparable to morphological features found in humans and piglets. Hence the SD mouse represents an animal model for morphologic and embryonic investigations of complex anorectal malformations.     

Cardiovascular anomalies with imperforate anus.

In 68 patients with anorectal malformations cardiovascular anomalies (CVA) were seen in 15 and genitourinary (GU) anomalies in 30. CVA were more frequent (33%) whenever there was a GU anomaly. Ventricular septal defect was the most frequent lesion. All but 1 CVA occurred with type III anorectal malformation. The complexity of the cardiac lesion did not parallel that of the GU anomaly.     

A novel association of duodenal atresia, malrotation, segmental dilatation of the colon, and anorectal malformation

We describe two female neonates who suffered from four gastrointestinal anomalies, including duodenal stenosis or atresia, malrotation, segmental dilatation of the colon, and anorectal malformation. Each patient was managed by two or three operations, resulting in good bowel movements. Since this is the first report of four gastrointestinal anomalies, these cases may provide clues to elucidate the etiology of gastrointestinal tract developmental abnormalities.     

The great divide: septation and malformation of the cloaca,and its implications for surgeons

The anorectal and urogenital systems arise from a common embryonic structure termed cloaca. Subsequent development leads to the division/septation of the cloaca into the urethra, urinary bladder, vagina, anal canal, and rectum. Defective cloacal development and the resulting anorectal and urogenital malformations are some of the most severe congenital anomalies encountered in children. In the most severe form in females, the rectum, vagina, and urethra fail to develop separately and drain via a single common channel known as a cloaca into the perineum. In this review, we summarize our current knowledge of embryonic cloaca development and malformation, and compare them to what has already been described in the literature. We describe the use of mouse models of cloaca malformation to understand which signaling pathways and cellular mechanisms are involved in the process of normal cloaca development. We also discuss the embryological correlation of the epithelial and stromal histology found in step sections of the common channel in 14 human cloaca malformations. Finally, we highlight the significance of these findings, compare them to prior studies, and discuss their implications for the pediatric surgeons. Understanding and identifying the molecular basis for cloaca malformation could provide foundation for tissue engineering efforts that in the future would reflect better surgical reconstruction and improved quality of life for patients.     

Anorectal malformation with malrotation of gut.

Infants with anorectal anomaly have a high risk of having other congenital anomalies, but associated gastrointestinal tract anomalies are quite rare. Malrotation of gut is rarely associated with anorectal anomaly. We report two such cases of anorectal malformation with malrotation of gut. The high index of suspicion, diagnostic difficulty and surgical management with avoidance of appendicectomy in these neonates is discussed.     

Anorectal malformation with ileal atresia

A low-type anorectal malformation associated with ileal atresia is described. It was very difficult to classify the anorectal malformation due to the presence of ileal atresia. Such anomalies are rare. A review of the literature on previously reported cases in Japan is presented. The possibility of other alimentary obstructions should be considered when anorectal anomalies are present.     

A psychosocial follow-up of ten adolescents with low anorectal malformation

Ten adolescents, aged 12–16 (mean 14.5) years, with corrected low anorectal anomalies were assessed with regard to somatic condition, psychopathology and psychosocial functioning by semistructured interviews and questionnaires. Half of the patients still had a persistent dysfunction involving problems with constipation and/or soiling. Six of 10 adolescents met the criteria for a psychiatric diagnosis and had scores indicating mild to severe impairment of psychosocial function. Psychosocial functioning was correlated with chronic family difficulties. The findings are in contrast to previous studies and reveal hidden problems and unmet social needs. To optimize their mental health and psychosocial functioning, children with low anorectal anomalies need both somatic and psychosocial follow-up.     

Anorectal function and endopelvic dissection in patients with repaired imperforate anus

Fifty-eight patients with anorectal malformations were closely followed up for postoperative anorectal function. Constipation was noted shortly after anorectoplasty in 10 of 28 low anomalies (35.7%) treated with limited sagittal anorectoplasty (LSARP), in 18 of 25 high or intermediate anomalies (72.0%) treated with posterior sagittal anorectoplasty (PSARP), but in none of 5 high or intermediate anomalies treated with Rehbein's mucosa-stripping endorectal pull-through and anterior sagittal perineal anorectoplasty (R-ASAP). The constipation resolved mostly within 1–2 years after repair under conservative management, but persisted beyond 2 years after repair in 3/25 children with LSARP and 10/25 with PSARP. Anal soiling was noted in 1/23 (4.3%) LSARP and 6/22 (27.3%) PSARP patients, but normal anorectal function was attained in 20/23 LSARP (86.9%) and 11/22 PSARP patients (50.0%) by the time of toilet training. Manometric studies disclosed that the resting rectal pressure (RRP) was lower and the anorectal pressure gradient (ARPG) higher in the constipated than the non-constipated children, while the RRP was higher and the ARPG lower in the soiled than the non-soiled patients. The ARPG after R-ASPA was close to that of non-constipated and in between that of the constipated and soiled patients. The rectoanal sphincter inhibitory reflex was not related to defecation status or surgical procedures, but showed a tendency toward positive conversion with time or after exclusion of ectatic terminal bowel in the severely constipated. It is concluded that anorectal function in patients with repaired imperforate anus seems to be more affected by the extent of endopelvic dissection than by preservation of the terminal bowel or sphincter muscles.     

Sirenomelia dipus in a dizygotic twin

A rare case of sirenomelia in a LBW, IUGR & second of a dizygotic twin having multiple congenital anomalies is being reported. Apart from the features of sirenomelia, the newborn had a single umbilical artery, radial hypoplasia, total anorectal & urogenital agenesis and undetermined sex. The single umbilical artery had a normal origin from the iliac artery. There was no Vitelline arterial steal phenomenon. Theories put forward regarding etiopathogenesis are discussed. We conclude that the anomalies in the present case are difficult to be explained with earlier proposed theories. This puts an emphasis on reconsideration of old theory of genetic injury to the embryo by unknown factors.     

Anorectal malformations — results of treatment and long-term follow-up in 208 patients

During a 20-year period (1964–1983) 208 patients with anorectal malformations (143 males, 65 females) were treated; 98 had low and 110 had high or intermediate malformations. Associated anomalies were detected in 67.8%. The overall mortality in the series was 14.4%; most deaths were related to associated anomalies and/or prematurity. Four different procedures were used for high and intermediate anomalies: (1) abdominoperineal (18 cases); (2) sacroabdominoperineal (38); (3) sacroperineal (8); and (4) posterior sagittal anorectoplasty (7). Neonatal anoplasty was used to correct male low anomalies. Female low and intermediate anomalies with vestibular fistula were treated with anal transposition. More than one-half of the patients with high or intermediate anomalies had complications related to surgical therapy. Major secondary surgery was performed in 41 cases (12 resections of megarectum, 29 late sphincter reconstructions). Of the living patients, 90% (159/178) were followed up for 5–25 years. A majority (93%) of the patients with low anomalies had a good outcome at the last follow-up examination. In patients with high and intermediate anomalies continence improved with time; the greatest improvement occurred after 10 years of age. At the last follow-up examination 73% of the patients with high or intermediate anomalies had acceptable social continence. Manometric evaluation revealed a rectoanal inhibitory reflex in all assessed patients with a low anomaly, indicating a functioning internal sphincter. In patients with intermediate and high anomalies a rectoanal inhibitory reflex was found only when full-thickness terminal bowel had been used in the reconstruction (by perineal and posterior sagittal repair); presence of the reflex correlated with superior fecal control. Acceptable fecal continence may be achieved in the majority of patients with anorectal anomalies. Operative methods that optimally utilize the voluntary sphincters and preserve the potential internal sphincter in the terminal rectal pouch seem to facilitate earlier development of fecal continence. Offprint requests to: R. Rintala     

Sirenomelia dipus in a dizygotic twin

A rare case of sirenomelia in a LBW, IUGR & second of a dizygotic twin having multiple congenital anomalies is being reported. Apart from the features of sirenomelia, the newborn had a single umbilical artery, radial hypoplasia, total anorectal & urogenital agenesis and undetermined sex. The single umbilical artery had a normal origin from the iliac artery. There was no Vitelline arterial steal phenomenon. Theories put forward regarding etiopathogenesis are discussed. We conclude that the anomalies in the present case are difficult to be explained with earlier proposed theories. This puts an emphasis on reconsideration of old theory of genetic injury to the embryo by unknown factors.