Nadine Zwink

Parental risk factors and anorectal malformations: systematic review and meta-analysis.

BackgroundAnorectal malformations (ARM) are rare forms of congenital uro-rectal anomalies with largely unknown causes. Besides genetic factors, prenatal exposures of the parents to nicotine, alcohol, caffeine, illicit drugs, occupational hazards, overweight/obesity and diabetes mellitus are suspected as environmental risk factors.MethodsRelevant studies published until August 2010 were identified through systematic search in PubMed, EMBASE, ISI Web of Knowledge and the Cochrane Library databases. Furthermore, related and cross-referencing publications were reviewed. Pooled odds ratios (95% confidence intervals) were determined to quantify associations of maternal and paternal smoking, maternal alcohol consumption, underweight (body mass index [BMI] < 18.5), overweight (BMI 25-29.9), obesity (BMI ≥30) and maternal diabetes mellitus with ARM using meta-analyses.Results22 studies that reported on the association between prenatal environmental risk factors and infants born with ARM were included in this review. These were conducted in the United States of America (n = 12), Spain (n = 2), Sweden (n = 2), the Netherlands (n = 2), Japan (n = 1), France (n = 1), Germany (n = 1) and Hungary (n = 1). However, only few of these studies reported on the same risk factors. Studies were heterogeneous with respect to case numbers, control types and adjustment for covariates. Consistently increased risks were observed for paternal smoking and maternal overweight, obesity and diabetes, but not for maternal smoking and alcohol consumption. In meta-analyses, pooled odds ratios (95% confidence intervals) for paternal smoking, maternal overweight, obesity, pre-gestational and gestational diabetes were 1.53 (1.04-2.26), 1.25 (1.07-1.47), 1.64 (1.35-2.00), 4.51 (2.55-7.97) and 1.81 (1.23-2.65), respectively.ConclusionEvidence on risk factors for ARM from epidemiological studies is still very limited. Nevertheless, the few available studies indicate paternal smoking and maternal overweight, obesity and diabetes to be associated with increased risks. Further, ideally large-scale multicentre and register-based studies are needed to clarify the role of key risk factors for the development of ARM.

Research perspectives in the etiology of congenital anorectal malformations using data of the International Consortium on Anorectal Malformations: evidence for risk factors across different populations

PurposeThe recently established International Consortium on Anorectal Malformations aims to identify genetic and environmental risk factors in the etiology of syndromic and nonsyndromic anorectal malformations (ARM) by promoting collaboration through data sharing and combined research activities.MethodsThe consortium attempts to recruit at least 1,000 ARM cases. DNA samples are collected from case–parent triads to identify genetic factors involved in ARM. Several genetic techniques will be applied, including SNP arrays, gene and whole exome sequencing, and a genome-wide association study. Questionnaires inquiring about circumstances before and during pregnancy will be used to obtain environmental risk factor data.ResultsCurrently, 701 ARM cases have been recruited throughout Europe. Clinical data are available from all cases, and DNA samples and questionnaire data mainly from the Dutch and German cases. Preliminary analyses on environmental risk factors in the Dutch and German cohort found associations between ARM and family history of ARM, fever during first trimester of pregnancy and maternal job exposure to cleaning agents and solvents.ConclusionFirst results show that both genetic and environmental factors may contribute to the multifactorial etiology of ARM. The International Consortium on Anorectal Malformations will provide possibilities to study and detect important genes and environmental risk factors for ARM, ultimately resulting in better genetic counseling, improved therapies, and primary prevention.

Unexpected results of a nationwide, treatment-independent assessment of fecal incontinence in patients with anorectal anomalies

PurposeTo determine the anorectal function in patients with anorectal malformations (ARM) in order to facilitate patient counseling and follow-up.MethodsData were collected by the German network for urorectal malformations (CURE-Net) according to the International Krickenbeck consensus. Questionnaires on bowel function and a defecation protocol were completed by the families/patients. The clinical findings were assessed from the patients’ clinical records.ResultsTwo hundred and ninety-seven patients with ARM were assessed, 175 patients gave complete data on continence, 52 of them were excluded due to mental retardation, age, and earlier type of pullthrough. Complete continence was found in 27xa0%, perineal fistula in 40xa0%, rectourethral/vesical in 10xa0%, vestibular in 24xa0%, cloaca in 0xa0%. Krickenbeck grade 1 soiling: 42xa0%, grade 2 and 3: 31xa0%. Forty-nine percent of the incontinent patients practiced bowel management, reaching continence in 19xa0%. The statement of constipation (67xa0%) was validated with the last clinical findings, showing coprostasis in 46xa0%, “Not suffering constipation” was confirmed in 61xa0% and falsified in 29xa0%.ConclusionARM patients in Germany, as assessed by independent researchers, show a high rate of fecal incontinence and insufficiently treated constipation. Parents should be counseled accordingly and motivated to engage in consequent follow-up. Intensified efforts in the conservative treatment of constipation and fecal incontinence are crucial to improvement.

Assisted reproductive techniques and the risk of anorectal malformations: a German case-control study

BackgroundThe use of assisted reproductive techniques (ART) for treatment of infertility is increasing rapidly worldwide. However, various health effects have been reported including a higher risk of congenital malformations. Therefore, we assessed the risk of anorectal malformations (ARM) after in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI).MethodsData of the German Network for Congenital Uro-REctal malformations (CURE-Net) were compared to nationwide data of the German IVF register and the Federal Statistical Office (DESTATIS). Odds ratios (95% confidence intervals) were determined to quantify associations using multivariable logistic regression accounting for potential confounding or interaction by plurality of births.ResultsIn total, 295 ARM patients born between 1997 and 2011 in Germany, who were recruited through participating pediatric surgeries from all over Germany and the German self-help organisation SoMA, were included. Controls were all German live-births (nu2009=u200910,069,986) born between 1997 and 2010. Overall, 30 cases (10%) and 129,982 controls (1%) were born after IVF or ICSI, which translates to an odds ratio (95% confidence interval) of 8.7 (5.9–12.6) between ART and ARM in bivariate analyses. Separate analyses showed a significantly increased risk for ARM after IVF (OR, 10.9; 95% CI, 6.2–19.0; Pu2009<u20090.0001) as well as after ICSI (OR, 7.5; 95% CI, 4.6–12.2; Pu2009<u20090.0001). Furthermore, separate analyses of patients with isolated ARM, ARM with associated anomalies and those with a VATER/VACTERL association showed strong associations with ART (ORs 4.9, 11.9 and 7.9, respectively). After stratification for plurality of birth, the corresponding odds ratios (95% confidence intervals) were 7.7 (4.6–12.7) for singletons and 4.9 (2.4–10.1) for multiple births.ConclusionsThere is a strongly increased risk for ARM among children born after ART. Elevations of risk were seen after both IVF and ICSI. Further, separate analyses of patients with isolated ARM, ARM with associated anomalies and those with a VATER/VACTERL association showed increased risks in each group. An increased risk of ARM was also seen among both singletons and multiple births.

De novo 13q deletions in two patients with mild anorectal malformations as part of VATER/VACTERL and VATER/VACTERL-like association and analysis of EFNB2 in patients with anorectal malformations

Anorectal malformations (ARMs) comprise a broad spectrum of conditions ranging from mild anal anomalies to complex cloacal malformations. In 40–50% of cases, ARM occurs within the context of defined genetic syndromes or complex multiple congenital anomalies, such as VATER/VACTERL (vertebral defects [V], ARMs [A], cardiac defects [C], tracheoesophageal fistula with or without esophageal atresia [TE], renal malformations [R], and limb defects [L]) association. Here, we report the identification of deletions at chromosome 13q using single nucleotide polymorphism‐based array analysis in two patients with mild ARM as part of VATER/VACTERL and VATER/VACTERL‐like associations. Both deletions overlap the previously defined critical region for ARM. Heterozygous Efnb2 murine knockout models presenting with mild ARM suggest EFNB2 as an excellent candidate gene in this region. Our patients showed a mild ARM phenotype, closely resembling that of the mouse. We performed a comprehensive mutation analysis of the EFNB2 gene in 331 patients with isolated ARM, or ARM as part of VATER/VACTERL or VATER/VACTERL‐like associations. However, we did not identify any disease‐causing mutations. Given the convincing argument for EFNB2 as a candidate gene for ARM, analyses of larger samples and screening of functionally relevant non‐coding regions of EFNB2 are warranted. In conclusion, our report underlines the association of chromosome 13q deletions with ARM, suggesting that routine molecular diagnostic workup should include the search for these deletions. Despite the negative results of our mutation screening, we still consider EFNB2 an excellent candidate gene for contributing to the development of ARM in humans.

Phenotype severity in the bladder exstrophy-epispadias complex: Analysis of genetic and nongenetic contributing factors in 441 families from North America and Europe

OBJECTIVEnTo identify genetic and nongenetic risk factors that contribute to the severity of the bladder exstrophy-epispadias complex (BEEC).nnnSTUDY DESIGNnPatients with BEEC from North America (n = 167) and Europe (n = 274) were included. The following data were collected: associated anomalies, parental age at conception, mode of conception, periconceptional folic acid supplementation, maternal risk factors during pregnancy, and environmental risk factors. The patients were divided into 3 subgroups according to phenotype severity: (i) mild, epispadias (n = 43); (ii) intermediate, classic bladder exstrophy (n = 366); and (iii) severe, cloacal exstrophy (n = 31). These subgroups then were compared with identify factors that contribute to phenotype severity.nnnRESULTSnMales were overrepresented in all subgroups. A relatively high prevalence of cleft lip, with or without cleft palate, was observed. Maternal smoking and medical radiation during the first trimester were associated with the severe cloacal exstrophy phenotype. Compliance with periconceptional folic acid supplementation was associated with the mildest phenotype (epispadias).nnnCONCLUSIONSnPericonceptional folic acid supplementation appears to prevent the development of the severe phenotype of BEEC.

Genome-wide Association Study and Meta-Analysis Identify ISL1 as Genome-wide Significant Susceptibility Gene for Bladder Exstrophy

The bladder exstrophy-epispadias complex (BEEC) represents the severe end of the uro-rectal malformation spectrum, and is thought to result from aberrant embryonic morphogenesis of the cloacal membrane and the urorectal septum. The most common form of BEEC is isolated classic bladder exstrophy (CBE). To identify susceptibility loci for CBE, we performed a genome-wide association study (GWAS) of 110 CBE patients and 1,177 controls of European origin. Here, an association was found with a region of approximately 220kb on chromosome 5q11.1. This region harbors the ISL1 (ISL LIM homeobox 1) gene. Multiple markers in this region showed evidence for association with CBE, including 84 markers with genome-wide significance. We then performed a meta-analysis using data from a previous GWAS by our group of 98 CBE patients and 526 controls of European origin. This meta-analysis also implicated the 5q11.1 locus in CBE risk. A total of 138 markers at this locus reached genome-wide significance in the meta-analysis, and the most significant marker (rs9291768) achieved a P value of 2.13 × 10−12. No other locus in the meta-analysis achieved genome-wide significance. We then performed murine expression analyses to follow up this finding. Here, Isl1 expression was detected in the genital region within the critical time frame for human CBE development. Genital regions with Isl1 expression included the peri-cloacal mesenchyme and the urorectal septum. The present study identified the first genome-wide significant locus for CBE at chromosomal region 5q11.1, and provides strong evidence for the hypothesis that ISL1 is the responsible candidate gene in this region.

Inheritance of the VATER/VACTERL association

VATER/VACTERL association refers to the non-random co-occurrence of the following component features: vertebral defects, anal atresia, cardiac malformations, tracheoesophageal atresia, renal abnormalities, and limb defects. Recently, Solomon et al. (Hum Genet 127:731–733, 2010) observed an increased prevalence of component features among first-degree relatives of VATER/VACTERL patients suggesting that in some patients, the disorder may be inherited. To replicate these findings, we investigated 87 VATER/VACTERL patients with the presence of a minimum of three component features and their first-degree relatives (nxa0=xa0271). No increase in the overall prevalence of component features was observed in first-degree relatives compared to the general population (χ²xa0=xa02.68, pxa0=xa00.10). Separate analysis for the prevalence of single component features showed a higher prevalence of tracheoesophageal fistula/atresia among first-degree relatives compared to the general population (OR 17.65, 95xa0% CI 2.47–126.05). However, this was based on occurrence in one family only. Our findings suggest that although familial occurrence renders a genetic contribution likely, the overall risk of recurrence among the first-degree relatives of patients with VATER/VACTERL association is probably very low. Since the patients in the present study were young and no offspring could be studied, estimation of the role of de novo mutations in the development of VATER/VACTERL was not possible.

Sexual function in adult patients with classic bladder exstrophy: A multicenter study

BACKGROUNDnThe bladder exstrophy-epispadias complex (BEEC) comprises a spectrum of congenital anomalies that represents the severe end of urorectal malformations, and has a profound impact on continence as well as sexual and renal functions.nnnOBJECTIVEnThe relation between severity of BEEC and its associated functional impairments, on one hand, and the resulting restrictions in quality of life and potential psychopathology determine the patients outcome. It is important for improving further outcome to identify BEEC-related sources of distress in the long term. Genital function and sexuality becomes an important issue for adolescent and adult BEEC individuals. Hence, the present study focused on sexual function and psychological adaption in patients with BEEC.nnnSTUDY DESIGNnIn a multicenter study 52 patients (13 females, 39 males) with classic bladder exstrophy (BE) with their bladders in use were assessed by a self-developed questionnaire about sexual function, and psychosexual and psychosocial outcome. The patients were born between 1948 and 1994 (median age 31 years).nnnRESULTSnTwelve of 13 (92%) females and 25 of 39 (64%) males with classic BE had answered the questions on sexual function. Of these, 50% females and 92% males answered that they masturbated. Females had sexual intercourse more frequently. Six (50%) females affirmed dyspareunia whereas only two (8%) males reported pain during erection. Eight (67%) females specified having orgasms. Eighteen (72%) males were able to ejaculate. Two males and none of the females lived in a committed partnership (Figure). Two (15%) females and 13 (33%) males answered all psychosocial questions. The majority of these patients had concerns about satisfactory sexuality and lasting, happy partnerships. A minority of patients of both sexes were willing to answer psychosocial questions. Sexual activity and relationships of many adult BE patients seems to be impaired. Not surprisingly, sexual activity and awareness were different in males and females even in a multi-organ anomaly.nnnDISCUSSIONnTo date, one of the main goals of the medical treatment of BEEC/BE patients is to enable normal sexual life and fertility. However, only a few outcome studies have focused on these issues with contradicting results, most of them not using standardized outcome measures. In accordance with other studies, our female BE patients have dyspareunia and most of our male BE patients were able to ejaculate. But the question of normal force of ejaculation, ejaculated volume, or semen analysis remains unanswered. Despite partial confirmation of previous findings, there is inconsistency referring to the outcome measured by the available studies. This might in part be explained by the fact that, other than this study, most previous studies are the result of single-institution experience. Thus, selection bias in the patient sampling due to different a clinical collective in different hospitals may be the consequence. Furthermore, patients honesty and self-reflection in answering difficult questions regarding their sexual and cosmetic impairments is questionable. In addition, studies include a wide range of age groups and are connected with this life period. Fears and condition-specific anxieties might change over time. Hence, the strengths of this study are the nationwide and treating physician-independent data acquisition as well as the large sample size of adult patients with a very rare congenital malformation. Unfortunately, more detailed analyses on sexual function and current psychosocial situation, for example correlation of data with clinical symptoms such as continence status, was not possible as data were mainly not answered by patients.nnnCONCLUSIONnTo improve the quality of life of patients with BEEC/BE, treatment and follow-up should emphasize physical but also psychological care in these patients. Physicians should further re-evaluate their preconceptions and should take care of the patients throughout their lives.

Sexual function in adults with anorectal malformation: psychosocial adaptation. German Network for Congenital Uro-REctal Malformations (CURE-Net)

PurposeThe aim of the German Network for Congenital Uro-REctal Malformations (CURE-Net) is to collect data of affected patients with anorectal malformation (ARM) to investigate molecular causes, clinical implications and psychosocial outcome. The current issue was to examine sexual function and to explore psychosocial adaptation in adults with ARM.MethodsThis qualitative study using narrative inquiry is part of a larger multi-center study of clinical queries and quality of life in patients with ARM. The guided interview focused on analysis of sexual function.Results55 adult patients with ARM (23 females, 32 males, median age 23xa0years, range from 18 to 56xa0years) were investigated via standardized case-report forms comprising interview, analysis of medical data and personal questionnaires. In the female patients, 8 (35xa0%) of them lived alone and 15 (65xa0%) had sexual intercourse. In the male patients, the majority of 20 (69xa0%) patients lived alone and 13 (45xa0%) had sexual intercourse. 6 of the females got pregnant, 5 got 2 or more children. 3 of the men induced 2 or more pregnancies and fathered children.ConclusionBesides reconstructing the ARM, another main goal is the preservation of sexual function. According to our data, there seems to be a close relationship between psychosocial development and sexual activity.