Anorectal Malformations

Aprodu, Diaconescu, Olaru, Gimiga, Stefanescu, Ioniuc, Iorga, Sarbu, Ciongradi

Abstract

Introduction: Anorectal malformations (ARM) represent a group of commonly encountered congenital anomalies in pediatric surgery practice, with an incidence of 2 in 1000 to 1 in 5000 live births but significant variations between different regions throughout the world. (1, 2) There is a wide spectrum of presentation ranging from low perineal fistula to high anomalies with complex surgical management. (3, 4) ARM are often associated with a complex range of another anomalies i.e. esophageal atresia, central nervous system, cardiovascular, urogenital, gastrointestinal and skeletal. (5, 6) Advances in the imaging techniques and improvement in knowledge of the embryology, anatomy and physiology of ARM cases have refined diagnosis and surgical therapy. (7) Classical approach of this pathology procedures moved forward PSARP and minimal invasive techniques with a stable goal of improving anatomical and functional outcome and quality of life. (8) Even if PSARP and its variants became the basic surgical treatment of ARM, constipation and fecal incontinence still remain the main concerns regarding the long time outcome in these patients. (9)

Material and Methods: We performed a retrospective study by analyzing clinical records of all ARM patients managed in the Pediatric Surgery Department of “St. Mary” Children Emergency Hospital of Iasi, Romania in a 20 year period (1994-2014). Data collected included social and demographical characteristics both for mother and child, birth-weight, type of ARM, clinical features including associated malformations, imaging tests, initial and definitive surgical approach and postoperative outcome, comprising a long term follow-up regarding functional aspects, psychological modifications associated with chronic disabilities, social insertion and quality of life.

Results: The patient series included 146 children comprising 85 boys and 61 girls, aged 1 day–2 years, median age being 46.4 +/- 5.7 days. In our report we found a male predominance (58.21% vs 41.78%) together with a higher frequency in neonates with low birth weight (68.4% from all patients, n=100). A semnificative percentage of these children originated from rural areas (64.4%, n=94), and from families with low incomes (47.3%, n=69). Mothers’ age ranged from 16 to 42 years, median value being 21,3+/-2,3 years.

The initial diagnosis was made in the first four days of life by a full physical examination in 120 (82.19%) patients, during the first year in 14 (9.58%) cases and after one year in 12 children (8.21%) respectively. In the cases with delayed diagnosis the main complaint for medical presentation was chronic constipation. Even if most of the patients presented in our department were usually diagnosed at birth, some of them were addressed beyond the early newborn period without a correct diagnosis of the anomaly. All these cases were patients with perineal fistula, both males and females or girls with vestibular fistula, in which a superficial examination of perineal area and the presence of feces evacuation through the fistula in the first days of life led to a diagnosis delay. Subsequently these children developed constipation consistently coinciding with a change in their diet from breast milk to formula or at the time of switching to solid food, so they were addressed for a pediatric surgical examination that identified the malformation. The commonest mode of presentation in the neonatal period was abdominal distension, vomiting and failure to pass meconium associated with an abnormal aspect of the perineum (with or without the presence of an orifice). At perineal inspection the most frequent clinical sign we have identified was the absence of a normal anal opening. Other findings frequently encountered on physical examination were a bulge in the perineum or an anterior anal opening, meconium in urine and passing of stool from vestibule or vagina in girls. Older patients presented with constipation and/or narrow anal opening. (Table 1)

Table1.Associations of clinical findings in children with ARM

Clinical diagnostic of so called “low” ARM was made in almost all males and females sufferers while in complex cases further explorations were necessary. However all cases underwent plain thoracic and abdominal X-Ray together with cardiac and abdominal ultrasound to assess cardiac, genitourinary, vertebral and other associated anomalies. Invertography was practiced in 27 cases (18.49%) to determine the location of rectal pouch in patients without visible fistula (Fig 1). Another contrast studies i.e. rectal pouch examination, fistulography and urethrography was performed in 40 cases (27.39%) while voiding cystography in 15 cases (10.27%), to detect the rectal urethral fistula or associated vesicoureteral reflux. Endoscopic evaluation of the genitourinary tract was practiced in 62 patients (42.46%), including 11 cases of cloaca, to estimate the complexity of the malformation. In these, the length of the common channel was in 8 cases (72.72%) less than 3 cm. Other endoscopic findings included: presence of a septate vagina (2 cases) and recto-urethral fistula identification (3 cases). In two cases (1.36%) perineal ultrasound measured the distance between the rectal pouch and perineal skin. Finally loop-o-grams were practiced in 4 cases with prior colostomy. None of the patients had CT or MRI explorations.

Fig.1 Invertography: The position of the rectal pouch can be appreciated measuring the distance from the perineal skin (identified by a metal marker)

Regarding the type of ARM, according to Pena classification, there were 87 perineal fistulas (59.58%), 26 cases (17.80%) of imperforate anus without fistula, 14 vestibular fistulas (9.58%), 11 cases (7.53%) of cloaca, 6 recto-urethral fistulas (4.10%), and two patients with rectal atresia (1.4%). The most frequent types encountered in male patients were perineal fistula and imperforate anus without fistula, while in females were perineal fistula followed by vestibular fistula and cloaca.

(Table 2, Fig. 2)

Table 2. Case distribution of the patients with ARM (according to Pena classification) (3)

Fig.2. Anorectal malformations-clinical aspects. A) Perineal fistula; B) Vestibular fistula; C) Recto-urethral fistula

Associated abnormalities were found in 38 patients (26.02%), some of them having two or even three inborn defects. The most common were genitourinary lesions in 14 patients (9.58%) including congenital hydronephrosis, hypospadias, renal agenesia, undescended testis and Mayer Rokitansky syndrome. Cardiovascular anomalies i.e. Fallot tetralogy, ventricular or atrial septal defect, aortic coarctation or left ventricle hypoplasia were observed in 11 cases (7.53%).We remarked a notable incidence of Down syndrome (12 cases; 8.21%), esophageal atresia (8 cases; 5.47%), vertebral anomalies (mielomeningoceles) (6 cases; 4.10%) and omphalocele, cloacal exstrophy, imperforate anus and spinal defects complex (OESI) (2 cases; 1.36%).

Surgical treatment was performed in 142 out of 146 patients; four patients died before surgery due to associated multiple congenital anomalies. Surgical approach and timing were imposed by the type and anatomy of the malformation, general condition at the time of presentation and additional pathology. (Table 3)

Table 3: Types of surgical procedures in patients with ARM

Thirty three cases (23.23%) underwent a colostomy; in 30 children it was placed at the transverse colon and in other three a divided colostomy was placed at the end of the descendent colon. In female, all patients with cloaca and vestibular fistula received a stomy, while in male all recto-urethral fistulas were managed in the same way. Also, the two patients with rectal atresia had a colostomy as first surgical procedure. The preliminary colostomy was part of three stage repair as all cases subsequently underwent posterior sagittal anorectoplasty (PSARP) or posterior sagittal anorectovaginourethroplasty (PSARVUP) and finally colostomy closure. In all cases with imperforate anus or perineal fistula mini PSARP or PSARP procedure was performed, without the need of a colostomy, so in 76.76% of the cases a definitive anorectal reconstruction was the initial surgical gesture of choice. (Fig. 3) The definitive treatment was represented by PSARP in 131 children (92.25%) with an additional abdominal access in 4 cases due to a high placed rectal pouch. All cloacal cases received a PSARPVUP procedure (7.74%) with abdominal access in 4 cases.

Fig 3.Anorectal malformation with rectourethral fistula. PSARP procedure

Early postoperative complications were minor being represented by perineal wound infection (4 patients), colostomy related complications – prolapse (4 cases) and stenosis (one case), all of them conservatively treated. We also reported three postoperative obstructions which required surgical therapy.

All patients were periodically followed up at 1, 3, 6, 12 months and then annually. In patients older than three years periodic monitoring included clinical continence, social insertion and quality of life. The functional outcome was considered as follows:

-good when a voluntary defecation was present with no or occasional soiling and no or mild constipation (manageable with diet and laxatives);

-acceptable when voluntary bowel movements were present with rare soiling (less than once a week) and moderate constipation (occasional /intermittent to persistent symptoms, manageable with occasional to regular use of medication+/- enema);

-poor in patients without voluntary defecation, moderate to severe soiling (more than once a week) and constipation of any degree or cases with isolated, severe constipation were included in this group.

The functional outcome was appreciated in 115 patients, aged more than three years old and the results were considered as good in 82 cases (71.30%) – presence of voluntary defecation, no or occasionally soiling, absent or mild constipation, acceptable in 25 cases (21.73%) – presence of bowel movement, rare soiling, moderate constipation) and poor in 8cases (6.95%)-absence of voluntary defecation, moderate to severe soiling; and any degree of constipation. In three of these cases additional surgery for continence was performed.

We noticed the presence of constipation in 39 children (33.91%), with a higher prevalence in perineal, vestibular fistula and imperforate anus group, but associated with good bowel control.On the other hand, cases with severe malformation (cloaca, rectourethral fistula, rectal agenesia) were found to have a high prevalence of soiling (8 cases), 6.95 %.

Only a group of ….children remained in our data-base until the age of 18; psychological assistance was provided in all cases..together with short psychotherapy meetings. The majority of the patients (80%) have normal intelligence (for IQ, M = 92) with no statistical significant difference between boys and girls, and a normal self-esteem. In school-age patients the sustain attention was below the norm. In 65% of the teenagers a low rate of body-consciousness and self-confidence was identified together with a relatively reduced autonomy and social contacts. Over half of these children avoided taking part to specific activities at this age. Psychological distress and emotional difficulties were identified in a higher rate for children over 10 and increased till adolescence (76% from all). Regarding parental attitude, …of the parents admitted being more depressed and overprotecting towards their children (especially on children with single parent).(….of the study group)

Discussions:

Malformations of the anus, anal canal and rectum are relatively common congenital defects, often coexisting in a significantly percentage of cases with another innate anomalies, whose high incidence however register major differences in geographic worldwide distribution. (1-3, 7) The causes of ARM are unknown but some families demonstrated a genetic predispositions of these conditions. (9, 10) They include a wide spectrum of inborn defects ranging from perineal fistulas which benefits from a relative simple cure to high defects imposing complex management. The frequency of serious clinical aspects differed in published data, most commonly seen defects being imperforate anus in both sexes, perineal/recto-urethral fistula and high lesions without fistula in boys and recto-vestibular fistulas and cloacae in girls. (7, 11) The multiple taxonomy of these lesions (Wingspread, Pena, Kirkenbeck) proposed in literature is yet confusing, most practitioners currently prefer a classification based on anatomical criteria depending on the position of the rectal pouch relative to the pubal-rectal sling, associated abnormalities (“syndromic” forms) and the presence or absence of fistulas. (2, 10, 11) Advances in imaging techniques with improvement in embryology, morphology and pathogenesis of these lesions have refined diagnostic and management moving from classical procedures to PSARP (VUP) and even minimal invasive methods. (12-18) In our report we found a male predominance together with a higher frequency in male neonates with low birth weight, originating from low income families. The median age of the mothers was 21.3+/-2.3 years, lower than the autochthonous average in the mentioned period, reported as being 22.5-26.0 by the National Statistics Institute. (19) These findings are coincident with other reports that suggested that male sex and intrauterine growth restriction together with mother’s age and low socioeconomic conditions may have a role in the risk of ARM. (20) Different studies also suggest that prenatal exposure to nicotine, alcohol, caffeine, illicit drugs, and overweight/obesity or diabetes mellitus are suspected as environmental risk factors. (21) In our series the majority of ARM were diagnosed at or soon after birth at routine postnatal examination. The absence of the anus or an abnormal appearance of perineum i.e. lack of or minimal passage of meconium but evidence of perineal, vestibular, recto-urethral fistula or persistent cloacae as a frequent deformity in female constituted obvious features of these anomalies. In addition, clinical signs in the neonatal period included vomits, abdominal distension and failure to pass meconium. We performed VACTERL (Vertebral anomalies, Anal atrezia, Cardiac defects, Tracheo-esophageal and/or Esophageal atrezia, Renal and Radial anomalies and Limb defects) screening in newborn males with a diagnosis of ARM at the first perineal inspection. We have identified however a number of 26 cases (18%) with a late diagnosis, most of them being children with perineal fistula (23 cases – 16%) or vestibular fistula (3 cases – 2%) misdiagnosed in the neonatal period and addressed to us due to severe constipation or narrow anal opening. IN TABEL ESTEConstipation/narrow anal opening 33 (22.60%) We consider that a correct physical examination of the perineal area is crucial in the neonatal period in order to avoid a delay in the diagnosis of these cases. In a quarter of cases ARM recorded associated abnormalities, the most common of them being urinary tract and cardiovascular defects. Our findings are not matching other author’s research that find an association between anorectal malformations and other inborn defects ranging from 68% to 78%. Regarding the type of associated congenital defects, literature reports a variety of syndromes such as tabel gasit ! (22).Some authors found an increase incidence of gastrointestinal and urogenital defects while others found more genitourinary and spinal anomalies. (14, 23) In our study we found genitourinary malformations and Down syndrome as being most frequent associations, followed by cardiovascular and esophageal atresia. ARM diagnostic in our series was mainly clinic, routine imaging including thoracic, abdominal, pelvic and spinal X-rays together with invertography, abdominal ultrasound and contrast studies along with endoscopic evaluation that aimed to evaluate the topography and extent of the lesion. The recent ARM-Net meeting brought minor modifications in the preoperative management of ARM regarding the 24 hours re-evaluation and cross-table lateral X-ray, compared to Levitt and Peña’s flow chart. (24, 25) It was suggested that in a newborn male with a perineal fistula, a cross-table lateral X-ray is unnecessary, this procedure being recommended only in cases of normal buttocks, normal spine, normal sacrum, and negative urinalysis on meconium; this protocol was extended to female neonates with no visible fistula. Early diagnosis was essential for short and long term prognosis. Almost all our patients underwent surgery, except few cases with delayed admission with major comorbidity and impaired general condition which died shortly after presentation. Neonates with low-type ARM benefits of minimal PSARP with good short and long term results. In males with high-type ARM cases PSARP was practiced, preceded by a protective colostomy. All cloaca cases were treated in the neonatal period by placing a colostomy and a PSARVUP procedure was later used as final surgery, sometimes with the need of an associated abdominal approach. Regarding the possibilities for treatment in girls with vestibular fistula, there are argues in the literature, as one or three stages surgery can be the choice. (26, 27) The supporters of perineal surgery in the neonatal period promote the idea of decreasing, by one stage surgery, the possible complications related to the anesthesia and morbidities related to the colostomy. However, a good bowel preparation is needed for this type of surgery, as there is a great risk of infection. We preferred to do a three stages surgery (colostomy, followed by PSARP and then colostomy closure) in a more cautious approach, although there are studies showing no significant differences in functional outcomes between a one stage and three stage operation. (26, 27)

The final goal of the surgical treatment in ARM is to obtain an anus placed within the muscular complex, by separating the rectum from the genital or urinary pathways and also to gain continence without any social impairment. The long time functional outcome is essential regarding the quality of life of these patients. During our follow up period, we observed that 71.30% of the cases acquired voluntary bowel movements, these results being similar with those previously reported by Pena (75%) or Sohyun Nam (84.8%). (8,28) Almost half (42.10%) of the children with high anomalies like cloaca, recto-urethral fistula and rectal atresia were identified with moderate and severe soiling (representing 6.95 % of patients in the follow-up group) result that seemed also similar to other series, as Rintala reported a rate of 30% soiling in these patients. (29)

Due to educational policies in Romania, from the last two decades, we have no case of integrated child in a special institution. Despite the good intellectual capacities, studies identify that a special education or remedial teaching is needed in more than half of the patients, problem difficult to be evaluated in our country due to the inconsistency of protocols regarding children with this kind of medical problems but in all our cases the family was taking care about the hygiene of the child and supervised him. All children from our sample reached normal schools.

31. School functioning and behaviour were assessed in a standardised interview. Intelligence, attention, self-esteem and quality of life were evaluated with validated tests and questionnaires. The intelligence quotient was normal: mean (standard deviation or SD) 98 (17) and 96 (17), respectively. However sustained attention was below the norm: mean (SD) Z-score -1.90 (1.94) and -1.43 (1.98) for ARM and HD patients; both p<0.01.

Regarding the QoL…………………DISCUTII MAGDA The multidisciplinary approach in case of a child with this diagnostic must take into consideration child and family psychological assistance. The psychotherapy effect on the patient depends a lot on the psychological profile but also on parents ‘ability to be involved in the longlife process of increasing the QoL for their children. Many studies pointed that a low score for QoL is identifying for parents having children with this diagnostic, comparing to other groups. Family becomes an important support if the there is no marital difficulties or mental health problems. Parental education should be also a priority for the multidisciplinary team that works for patient’ quality of life. A long term protocol must be used in order to supervise properly the patient’s quality of life but also the family psychosocial life (30).

Therapeutical intervention is needed after 3 years old. Multidisciplinary behavioural treatment (MBT) is an important teamwork method for intervention, offering psychological and physiotherapeutic therapy for children and their families and reduce psycho-social distress (34). This kind of approach was successfully applied for children over 3 years old in many countries and involves the surgeon, the psychologist and the pediatric physiotherapist. Although young children had poorer scores than older children before treatment, no important statistical differences in the favourable outcome of treatment were found between both groups after MBT. Somatic and behavioural factors seem to contribute to maintain this problem.

 Considering that children should pass to the adult stage as normally of possible, this kind of protocol should be adopted in order to assure the child well-being and the proper strategy for the family to cope with the problem.

Children over 3 years old were supervised over the years, till 18 years old. One of the most important goals for this type of diagnostic was to assure a better quality of life during their childhood and adolescence and to assure a slowly passing to their adult life. Important aspects of quality of life are related to their psychological well-being, physical well-being and the social support. Psychological assistance was provided in all cases and short meetings of psychotherapy were established each time the patient and the parent reached the hospital.

Regarding the psychological well-being, we identify that there is no correlation between ARM and some aspects of the psychological development, as previous studies from the literature are presented (35).

Psychological distress and emotional difficulties were identified in a higher rate for children over 10 and increases till adolescence (76%), because this turbulent period is usually associated to emotional and social distress due in most of the cases to their need for being physically admired and emotionally involved in a romantic relationship.

In what concerns the physical well-being, most of the children questioned reported additional pain and limitations due to their physical condition (31). After all, the physical problems are deeply involved in socialisation. Over half of the children are avoiding taking part to specific activities at this age (staying overnight with friends, having a romantic relationship travelling with school peers, spending holidays with grandparents, going to holiday camps etc)

The discussion with parents about the difficulties of their children during the years pointed that parents usually overprotect them emotionally and physically and are over involved by trying to control their physical integrity what increase the risks for behavioural and social problems.

Regarding the social support, we identified that the impact on parents ‘quality of life is important, parents being more depressed and overprotecting towards their children (especially on children with single parent). In what concerns the physical well-being, most of the children questioned reported additional pain and limitations due to their physical condition After all, the physical problems are deeply involved in socialisation. Over half of the children are avoiding taking part to specific activities at this age (staying overnight with friends, having a romantic relationship travelling with school peers, spending holidays with grandparents, going to holiday camps etc)

There is still an open discussion regarding the possibilities of correct quantification of the short and long distance outcomes. Despite our sometimes limited possibilities to investigate these children, we succeeded to have a correct approach to our cases with promising good early and over time results of definitive surgery; reduced morbidity and lack of postoperative mortality argues heartening our way of thinking in surgical treatment of this pathology. This study has several limitations being a single center report and providing only limited data concerning the long-time surveillance of the patients. We intend to focus our future research on vestibular fistula dilatation in selected patients. (low-birth weight <2.000 g or severe associated congenital anomalies).

Conclusions: A better understanding of pathogenesis with more accurate pre and intraoperative diagnosis together with continuous perfectible practice of established operative techniques appear as the essential conditions of success in ARM management aligning our team experience and expertise toward reputed centers. We sustain a multidisciplinary approach of these cases in complex teams including neonatologists, pediatric surgeons, pediatricians, psychologist and family doctors, together with a “surveilled” transition to adult gastroenterology centers.

Aknowledgements: to the Pediatric Surgery Department of “St. Mary” Children’s Emergency Hospital, Iasi, Romania

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