Cloaca Malformation Research Articles

A novel genotype-phenotype between persistent-cloaca-related VACTERL and mutations of 8p23 and 12q23.1.

The mechanism underlying anorectal malformations (ARMs)-related VACTERL (vertebral defects, anal atresia, cardiac defects, tracheo-esophageal fistula, and renal and limb abnormalities) remains unclear. Copy number variation (CNV) contributed to VACTERL pathogenicity. Here, we report a novel CNV in 8p23 and 12q23.1 identified in a case of ARMs-related VACTERL association. This 12-year-old girl presented a cloaca (urethra, vagina, and rectum opening together and sharing a single tube length), an isolated kidney, and a perpetuation of the left superior vena cava at birth. Her intelligence, growth, and development were slightly lower than those of normal children of the same age. Array comparative genomic hybridization revealed a 9.6-Mb deletion in 8p23.1-23.3 and a 0.52-Mb duplication in 12q23.1 in her genome. Furthermore, we reviewed the cases involving CNVs in patients with VACTERL, 8p23 deletion, and 12q23.1 duplication, and our case was the first displaying ARMs-related VACTERL association with CNV in 8p23 and 12q23.1. These findings enriched our understanding between VACTERL association and the mutations of 8p23 deletion and 12q23.1 duplication. IMPACT: This is a novel case of a Chinese girl with anorectal malformations (ARMs)-related VACTERL with an 8p23.1-23.3 deletion and 12q23.1 duplication. Cloaca malformation is presented with novel copy number variation in 8p23.1-23.3 deletion and 12q23.1 duplication.

Inversin (NPHP2) and Vangl2 are required for normal zebrafish cloaca formation

Nephronophthisis (NPH), an autosomal recessive ciliopathy, results from mutations in more than 20 different genes (NPHPs). These gene products form protein complexes that regulate trafficking within the cilium, a microtubular structure that plays a crucial role in developmental processes. Several NPHPs, including NPHP2/Inversin, have been linked to extraciliary functions. In addition to defining a specific segment of primary cilia (Inversin compartment), NPHP2 participates in planar cell polarity (PCP) signaling along with Dishevelled and Vangl family members.We used the mutant zebrafish line invssa36157, containing a stop codon at amino acid 314, to characterize tissue-specific functions of zebrafish Nphp2. The invssa36157 line exhibits mild ciliopathy phenotypes and increased glomerular and cloaca cyst formation. These mutants showed enhanced susceptibility to the simultaneous depletion of the nphp1/nphp2/nphp8 module, known to be involved in the cytoskeletal organization of epithelial cells. Notably, simultaneous depletion of zebrafish nphp1 and vangl2 led to a pronounced increase in cloaca malformations in the invssa36157 mutant embryos. Time-lapse imaging showed that the pronephric cells correctly migrated towards the ectodermal cells in these embryos, but failed to form the cloaca opening. Despite these abnormal developments, cellular fate does not seem to be affected in nphp1 and vangl2 MO-depleted invssa36157 mutants, as shown by in situ hybridizations for markers of pronephros and ectodermal cell development. However, significantly reduced apoptotic activity was observed in this double knockdown model, signifying the role of apoptosis in cloacal morphogenesis. Our findings underscore the critical interplay of nphp1, nphp2/Inversin, and vangl2 in orchestrating normal cloaca formation in zebrafish, shedding light on the complex molecular mechanisms underlying ciliopathy-associated phenotypes.

Surgical management strategy of alimentary tract duplication involving the rectum in children.

Alimentary tract duplication involving the rectum (ATD-R) is rare. The purpose of the study was to describe the features of pediatric ATD-R patients and propose a surgical management strategy. Nine consecutive children operated on for ATD-R at a tertiary center for pediatrics from January 2010 to June 2021 were retrospectively reviewed and followed up. Eighty-six children with the same diagnosis from the literature were reviewed to assist the investigation. Classifications of ATD-R consisted of cystic, tubular, and diverticular. Surgical treatment and histopathological examination identified six females and three males with ATD-R. Initial clinical symptoms included perianal lesions, abnormal discharge, and anorectal malformation (ARM). Apart from one tubular ATD-R patient with cloaca malformation, the other eight patients had normal-developed anorectum. Complete or partial lesion resection maintaining the integrity of the proper colorectum was a principle of surgery. Six patients were followed up for a median time of 71 (range 12-121) months with good prognoses. A surgical management strategy of ATD-R in children was proposed. ATD-R commonly occurred concurrently with normal-developed anorectum, seldom combined with ARM. ATD-R should be considered as a differential diagnosis in anorectal symptoms. The timely and appropriate operation was curative.

Clock genes rescue nphp mutations in zebrafish.

The zebrafish pronephros model, using morpholino oligonucleotides (MO) to deplete target genes, has been extensively used to characterize human ciliopathy phenotypes. Recently, discrepancies between MO and genetically defined mutants have questioned this approach. We analyzed zebrafish with mutations in the nphp1-4-8 module to determine the validity of MO-based results. While MO-mediated depletion resulted in glomerular cyst and cloaca malformation, these ciliopathy-typical manifestations were observed at a much lower frequency in zebrafish embryos with defined nphp mutations. All nphp1-4-8 mutant zebrafish were viable and displayed decreased manifestations in the next (F2) generation, lacking maternal RNA contribution. While genetic compensation was further supported by the observation that nphp4-deficient mutants became partially refractory to MO-based nphp4 depletion, zebrafish embryos, lacking one nphp gene, became more sensitive to MO-based depletion of additional nphp genes. Transcriptome analysis of nphp8 mutant embryos revealed an upregulation of the circadian clock genes cry1a and cry5. MO-mediated depletion of cry1a and cry5 caused ciliopathy phenotypes in wild-type embryos, while cry1a and cry5 depletion in maternal zygotic nphp8 mutant embryos increased the frequency of glomerular cysts compared to controls. Importantly, cry1a and cry5 rescued the nephropathy-related phenotypes in nphp1, nphp4 or nphp8-depleted zebrafish embryos. Our results reveal that nphp mutant zebrafish resemble the MO-based phenotypes, albeit at a much lower frequency. Rapid adaption through upregulation of circadian clock genes seems to ameliorate the loss of nphp genes, contributing to phenotypic differences.

Risk factors for end stage renal disease in children with anorectal malformation and outcome comparison to children with isolated urological anomalies

End stage renal disease (ESRD) requiring kidney transplant (KT) remains an important cause of morbidity in anorectal malformations (ARM) patients. Current literature is scarce on defining the risk factors for ESRD and the outcomes of KT in ARM patients. This study aimed to identify predisposing factors to ESRD in ARM patients and verify if the long term outcome of KT in these patients differs from pure urological anomalies (UA). Databases of ARM and KT patients treated at our center between 2000 and 2016 were used for comparing characteristics of ARM cases which developed ESRD and those who did not, and the outcome features of MAR-KT vs UA-KT. Out of 117 ARM patients, 9 developed ESRD. All of them had a complex ARM. Association with UA were significantly higher in ARM-KT compared to other ARM patients (100% vs. 52%, p=0.001). The most common UA associated to KT in ARM patients was renal dysplasia. During the same period 23 patients underwent KT as a sequelae of pure urological anomalies (UA-KT group). The most represented UA were primary vesico-ureteral reflux (65.2%) and posterior urethral valves (14%) in UA-KT (table 2). ARM-KT patients required more often hemodialysis before KT (50% vs. 8.7%, p=0.05) and an aorto-caval anastomosis at the transplant (75% vs. 30%, p=0.04) compared to UA-KT. Moreover ARM-KT patients experienced more often graft failure and and the need for a second KT (50% vs. 8.6%, p=0.02). To our knowledge, this is the first study describing the differences in terms of risk factors and outcomes of KT in ARM patients. We observed a need for KT in 7% of ARM, which is at the higher end of the range reported in the literature. Bilateral dysplasia and cloaca malformation seem the leading cause to ESRD for ARM patients compared to vesico-ureteral reflux and posterior urethral valve in UA-KT. Our experience showed that KT has worst outcome in ARM vs pure UA patients. Patients with complex ARM are more frequently associated to renal dysplasia which lead to KT. Graft in ARM patients seems to be the more vulnerable and prone to failure.

Prevalence and Association of Occult Spinal Dysraphism with Anorectal Malformation

Background: Anorectal malformation (ARM) is associated with occult spinal dysraphism (OSD). The guideline for screening for OSD in patients with ARM is still controversial. Objective: 1) To evaluate the prevalence of OSD in each type of ARM and to elucidate which types of ARM should be screened for underlying OSD. 2) To compare the methods used in radiologic screening for OSD, such as plain lumbosacral X-ray, spinal ultrasound (U/S), and spinal magnetic resonance imaging (MRI). Materials and Methods: The medical records of all patients with ARM treated at Siriraj Hospital between 2006 and 2016 were reviewed. Spinal dysraphism screening with lumbosacral X-ray, U/S, or MRI were performed depending on the surgeon’s request. Associated urinary tract anomalies were noted. Data of the surgical treatments, outcomes, and complications of treatments were collected. Results: Among the 204 ARM patients treated, 150 patients were screened for OSD, involving 150 lumbosacral X-ray, 65 U/S, and 39 MRI. The prevalence of OSD (n=33) in all types of ARM was 16.2%. The higher types of ARM had higher prevalence of OSD, except for vestibular fistula (20.5%). The prevalence of OSD in cloaca malformation, rectobladder neck fistula, rectoprostatic urethral fistula, rectobulbar urethral fistula, and perineal fistula were 28.6%, 33.3%, 16.7%, 12.5%, and 9.8%, respectively. Lumbosacral X-ray had a sensitivity of 51.7% and was not a good screening method. Sixteen of 65 U/S revealed OSD (24.6%). Tethered cord and syringomyelia were noted in nine and seven, respectively. Spinal MRI (n=39) revealed 27 OSD (69.2%) comprising 16 tethered cords, 12 spinal lipoma, and 10 syringomyelia. ARM associated with KUB anomalies had a statistically significant correlation with OSD. In 33 OSD, 17 patients (51.1%) were operated on. Fourteen received untethering spinal cord, while five had intradural lipoma excised. Conclusion: Patients with ARM had a high prevalence of OSD and should be screened for. U/S is the first-line method. MRI is strongly recommended in cloaca malformation, rectobladder neck fistula, rectoprostatic urethral fistula, vestibular fistula, and all ARM associated with KUB anomalies. Other types of ARM should be screened by MRI if feasible. Keywords: Spinal dysraphism, Tethered cord, Anorectal malformation

A New Approach to Cloaca: Laparoscopic Separation of the Urogenital Sinus.

Introduction: Cloaca malformation repair strategy is strongly dictated by common channel and urethral lengths. Mid to long common channel cloacas are challenging and often require laparotomy for dissection of pelvic structures. The balance of common channel and urethral lengths often dictates the approach for reconstruction. Laparoscopy has been utilized for rectal dissection but not for management of the urogenital (UG) structures. We hypothesized that laparoscopy could be applied to UG separation in reconstruction of cloaca malformations. Methods: Records were reviewed for 9 children with cloaca who underwent laparoscopic rectal mobilization and UG separation. Clinical parameters reviewed included demographics, relevant anatomic lengths, operative duration, transfusion requirements, and perioperative complications. Results: Repair was perfomed at a median (interquartile range) age of 12 (7, 15) months. Common channel length as measured by cystoscopy was 3.5 (3.3, 4.5) cm. There were no intraoperative complications. Transfusion requirements were minimal. Postoperative length of stay was 6 (5, 11) days. One patient developed a urethral web and 2 developed vaginal stenosis. One patient later underwent a laparotomy for obstruction due to a twisted rectal pull-through. Conclusions: Laparoscopic rectal mobilization and UG separation in long common channel cloaca are safe and well tolerated. Laparoscopy affords full evaluation of Mullerian structures and enables separation of the common UG wall, which may ultimately enhance long-term urinary continence.

Obstetrical Outcomes in Adult Patients Born with Complex Anorectal Malformations and Cloacal Anomalies: ALiteratureReview.

Patients born with complex anorectal malformations often have associated Müllerian anomalies, which might affect fertility and obstetrical outcomes. Other vertebral-anorectal-tracheoesophageal-renal-limbassociations, such as renal or cardiac anomalies, could also affect pregnancy intention, fertility rates, and recommendations about mode of delivery or obstetrical outcomes. Associated conditions present at birth, like hydrocolpos, could also potentially affect fertility. Depending on the complexity of the anomaly, primary reconstruction might include vaginoplasty, vaginal interposition, perineal body reconstruction, and extensive pelvic dissection. After the initial reconstruction, patients might have multiple additional surgeries for stoma reversal, bladder augmentation, and creation of conduits, all with potential for pelvic adhesions. Pregnancy intention, fertility rates, mode of delivery, and obstetrical outcomes data are limited in this patient population, making it challenging to counsel patients and their families. We sought to evaluate all available literature in an attempt to better counsel families. A PubMed literature search was undertaken to review this topic. Search terms of "cloaca," "anorectal malformation," "pregnancy," "cloacal exstrophy," "vaginal delivery," and "cesarean section" were used and citation lists from all identified articles were checked to ensure that all possible articles were included in the review. We also outline comorbidities from the fetal period to adulthood that might affect reproductive health. Of the articles on anorectal and cloacal anomalies, 13 reports were identified that covered obstetrical outcomes. They were in patients with previous anorectal malformation, cloaca, and cloacal exstrophy repair. Twenty-four pregnancies were reported in 16 patients. Two ectopic pregnancies, 5 spontaneous miscarriages, 1 triplet pregnancy, and 16 singleton pregnancies were reported with a total of 19 live births. Regarding the method of conception, 15/18 pregnancies occurred spontaneously and 3/18 were via assisted reproductive technology with invitro fertilization. There were 19 live births, of which at least 8 were preterm. Müllerian anatomy was reported in 8 of 13 articles. Only 2 patients underwent vaginal delivery (1 patient with repaired cloaca malformation had an operative vaginal delivery and 1 patient with repaired imperforate anus with rectovaginal fistula had a normal spontaneous vaginal delivery). The remaining patients all underwent a cesarean section. There were no reported cases of maternal mortality, and maternal morbidity was limited to recurrent urinary tract infections and worsening chronic kidney disease. There is a paucity of information regarding obstetrical outcomes in adult anorectal and cloaca patients. However, patients with previous cloacal repairs have achieved pregnancy spontaneously, as well as with invitro fertilization. Patients with repaired cloacal malformations are at increased risk of preterm birth and cesarean delivery. Most patients with cloacal anomalies have an associated Müllerian anomaly and therefore have an increased risk of preterm labor. From our review we conclude that contraception should be offered to patients not desiring pregnancy, and cesarean section is likely the preferred mode of delivery. On the basis of this review, we recommend proactive data collection of all such patients to document outcomes and collaboration among providers and between centers devoted to this complex patient population.

Prenatal diagnosis of cloacal malformation

Persistent cloaca malformation is the most severe type of anorectal and urogenital malformation. Decisions concerning the surgical treatment for this condition are taken during the first hours of life and may determine the quality of life of these patients. Thus, prenatal diagnosis becomes important for a prompt and efficient management of the fetus and newborn, and accurate counseling of the parents regarding its consequences and the future of the baby. Careful evaluation by ultrasonography, and further in-depth analysis with MRI, allow prenatal detection of characteristic findings, which can lead to diagnose or at least suspect this condition. We reviewed our experience and the literature in order to highlight the most important clues that can guide the physician in the differential diagnosis.

Pathology of cloaca anomalies with case correlation

During the fourth week of human embryo development, a transient common channel known as a cloaca is formed from which three cavities with three external orifices arises. Cloaca anomalies occur when there is failure of separation of the rectum, vagina, and urethra channel resulting in a single drain into the perineum. In our previous institutional studies, Runck et al.1 compared human and mouse cloaca development and found early mis-patterning of the embryonic cloaca deranged hedgehog and bone morphogenetic proteins (BMP) signaling. Also, our group reported the embryological correlation of the epithelial and stromal histology found in step sections of the common channel in 14 cloaca malformations in humans.2 In this review, we present the pathology of a 4-year-old female with a cloaca and VACTERL complex, and summarize our current knowledge of cloaca pathology. Furthermore, we suggest that careful pathological examination of cloaca specimens in conjunction with surgical orientation may result in a better understanding of the etiology of this condition.

WNT3 involvement in human bladder exstrophy and cloaca development in zebrafish.

Bladder exstrophy, a severe congenital urological malformation when a child is born with an open urinary bladder, is the most common form of bladder exstrophy-epispadias complex (BEEC) with an incidence of 1:30,000 children of Caucasian descent. Recent studies suggest that WNT genes may contribute to the etiology of bladder exstrophy. Here, we evaluated WNT-pathway genes in 20 bladder exstrophy patients using massively parallel sequencing. In total 13 variants were identified in WNT3, WNT6, WNT7A, WNT8B, WNT10A, WNT11, WNT16, FZD5, LRP1 and LRP10 genes and predicted as potentially disease causing, of which seven variants were novel. One variant, identified in a patient with a de novo nonsynonymous substitution in WNT3 (p.Cys91Arg), was further evaluated in zebrafish. Knock down of wnt3 in zebrafish showed cloaca malformations, including disorganization of the cloaca epithelium and expansion of the cloaca lumen. Our study suggests that the function of the WNT3 p.Cys91Arg variant was altered, since RNA overexpression of mutant Wnt3 RNA does not result in embryonic lethality as seen with wild-type WNT3 mRNA. Finally, we also mutation screened the WNT3 gene further in 410 DNA samples from BEEC cases and identified one additional mutation c.638G>A (p.Gly213Asp), which was paternally inherited. In aggregate our data support the involvement of WNT-pathway genes in BEEC and suggest that WNT3 in itself is a rare cause of BEEC.

PO-0664 Superglue, A Simple And Effective Method For Sealing An Untight Catheter For Peritoneal Dialysis

Introduction Acute renal failure is a severe complication in neonatal intensive care medicine. The only therapeutic option for renal replacement therapy in small infants or premature babies with acute renal failure is peritoneal dialysis. In this paper two case reports of sealing an untight peritoneal catheter with cyanoacrylate glue will be presented. Patient 1: Premature infant of 34 + 2 weeks gestational age. Dorsal cloaca malformation with megacystis and megaureter, peritoneal dialysis for 13 days. Patient 2: Term neonate of 40 + 4 weeks gestational age with meconium plug syndrome and volvulus, double ileostomy, necrotising enterocolitis and Morbus Hirschsprung. Alagille syndrome with renal malformation, peritoneal dialysis for 46 days. All catheters were extremely untight from the very beginning; effective dialysis was not possible. Sealing with fibrine glue was not efficient. Only sealing of the skin with cyanoacrylate glue allowed for effective peritoneal dialysis. Apart from gradually increasing irritation of the skin no serious side effects occurred. No dialysate entered the surrounding soft tissue although the subcutaneous part of the skin channel was always filled with dialysate. Conclusion It is possible to seal a catheter for peritoneal dialysis quickly and effectively with cyanoacrylate glue without serious complications. The existence of an ileostomy did not interfere with the dialysis.

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.

Defining the molecular pathologies in cloaca malformation: similarities between mouse and human

Anorectal malformations are congenital anomalies that form a spectrum of disorders, from the most benign type with excellent functional prognosis, to very complex, such as cloaca malformation in females in which the rectum, vagina and urethra fail to develop separately and instead drain via a single common channel into the perineum. The severity of this phenotype suggests that the defect occurs in the early stages of embryonic development of the organs derived from the cloaca. Owing to the inability to directly investigate human embryonic cloaca development, current research has relied on the use of mouse models of anorectal malformations. However, even studies of mouse embryos lack analysis of the earliest stages of cloaca patterning and morphogenesis. Here we compared human and mouse cloaca development and retrospectively identified that early mis-patterning of the embryonic cloaca might underlie the most severe forms of anorectal malformation in humans. In mouse, we identified that defective sonic hedgehog (Shh) signaling results in early dorsal-ventral epithelial abnormalities prior to the reported defects in septation. This is manifested by the absence of Sox2 and aberrant expression of keratins in the embryonic cloaca of Shh knockout mice. Shh knockout embryos additionally develop a hypervascular stroma, which is defective in BMP signaling. These epithelial and stromal defects persist later, creating an indeterminate epithelium with molecular alterations in the common channel. We then used these animals to perform a broad comparison with patients with mild-to-severe forms of anorectal malformations including cloaca malformation. We found striking parallels with the Shh mouse model, including nearly identical defective molecular identity of the epithelium and surrounding stroma. Our work strongly suggests that early embryonic cloacal epithelial differentiation defects might be the underlying cause of severe forms of anorectal malformations in humans. Moreover, deranged Shh and BMP signaling is correlated with severe anorectal malformations in both mouse and humans.

Wtip and Vangl2 are required for mitotic spindle orientation and cloaca morphogenesis

SummaryDefects in cilia and basal bodies function are linked to ciliopathies, which result in kidney cyst formation. Recently, cell division defects have been observed in cystic kidneys, but the underlying mechanisms of such defects remain unclear. Wtip is an LIM domain protein of the Ajuba/Zyxin family, but its role in ciliogenesis during embryonic development has not been previously described. We report Wtip is enriched in the basal body and knockdown of wtip leads to pronephric cyst formation, cloaca malformation, hydrocephalus, body curvature, and pericardial edema. We additionally show that wtip knockdown embryos display segment-specific defects in the pronephros: mitotic spindle orientation defects are observed only in the anterior and middle pronephros; cloaca malformation is accompanied by a reduced number of ciliated cells; and ciliated cells lack the striated rootlet that originates from basal bodies, which results in a lack of cilia motility. Our data suggest that loss of Wtip function phenocopies Vangl2 loss of function, a core planar cell polarity (PCP) protein located in the basal body protein. Furthermore, we demonstrate that wtip and vangl2 interact genetically. Taken together, our results indicate that in zebrafish, Wtip is required for mitotic spindle orientation in the anterior and middle of the pronephros, cloaca morphogenesis, and PCP, which may underlie the molecular etiology of ciliopathies.

Nephrocystin-4 is required for pronephric duct-dependent cloaca formation in zebrafish

NPHP4 mutations cause nephronophthisis, an autosomal recessive cystic kidney disease associated with renal fibrosis and kidney failure. The NPHP4 gene product nephrocystin-4 interacts with other nephrocystins, cytoskeletal and ciliary proteins; however, the molecular and cellular functions of nephrocystin-4 have remained elusive. Here we demonstrate that nephrocystin-4 is required for normal cloaca formation during zebrafish embryogenesis. Time-lapse imaging of the developing zebrafish pronephros revealed that tubular epithelial cells at the distal pronephros actively migrate between the yolk sac extension and the blood island towards the ventral fin fold to join the proctodeum and to form the cloaca. Nphp4-deficient pronephric duct cells failed to connect with their ectodermal counterparts, and instead formed a vesicle at the obstructed end of the pronephric duct. Nephrocystin-4 interacts with nephrocystin-1 and Par6. Depletion of zebrafish NPHP1 (nphp1) increased the incidence of cyst formation and randomization of the normal body axis, but did not augment cloaca malformation in nphp4-deficient zebrafish embryos. However, simultaneous depletion of zebrafish Par6 (pard6) aggravated cloaca formation defects in nphp4-depleted embryos, suggesting that nphp4 orchestrates directed cell migration and cloaca formation through interaction with the Par protein complex.

Three-dimensional reconstruction of the Ephrin-B2 female mouse model of anorectal malformations

Purpose Persistent cloaca is a rare, severe congenital anomaly. The Eph family receptor tyrosine kinases and their ligands, the ephrin family, mediate diverse embryonic cell-cell recognition events. We previously reported ephrin-B2lacZ/lacZ mice manifest male high imperforate anus and female persistent cloaca (Dravis et al. Dev Biol 2004; 271(2): 272-290). We studied and demonstrated via 3D-reconstruction whether altered ephrin-B2 signaling in female ephrin-B2 lacZ/lacZ mutant mice affect apoptosis, thereby possibly contributing to persistent cloaca malformation. Material and methods Female embryonic days 11.5, 13.5 and 16.5 (E11.5, E13.5 and E16.5) wild type (WT), ephrin-B2lacZ/+ (Z/+) and ephrin-B2 lacZ/lacZ (Z/Z) mice sections were dual labeled for ephrin-B2 and TUNEL immunohistochemistry. Anti-galactosidase antibody detected the ephrin-B2-gal fusion protein in Z/+ and Z/Z mice. WinSurf software was used for 3D reconstructions of the cloacal region. Results In WT E11.5 females, the cloacal membrane (CM) is intact. The urorectal septum (URS) is partially separating the cloaca into urogenital sinus and hindgut; no vagina has developed. In contrast, Z/Z females had poor cloacal development. Z/+ embryos showed widened URS. Apoptosis in WT females occurred prominently in CM, dorsal cloaca, and hindgut. In contrast, apoptosis in Z/Z females was limited to the endoderm of the poorly formed cloaca. These changes progressed throughout E13.5 and finally at E16.5, Z/Z females exhibited persistent cloaca. Conclusions The 3D reconstruction of the cloacal region provides a better understanding of the mechanism by which altered ephrin-B2 signaling yields persistent cloaca via diminished apoptosis in Z/Z mice.

Progression of white matter hyperintensities in elderly individuals over 3 years

The aims of this study were to examine white matter hyperintensities (WMHs) in the brains of elderly individuals, the rate of progression, the anatomic regions most vulnerable, and the predictors of change. We examined 51 healthy volunteers (mean age 71 years) with T2-weighted brain MRI on the same scanner 3 years apart. WMH volumes were determined by an automated method, and the anatomic location of change was determined for both deep WMHs (DWMHs) and periventricular WMHs (PVWMHs). The total brain WMH volume increased by 39.6%, i.e., 13.2% per year, with the change in DWMH being 43.8% and 29.7% in PVWMH. The increase was significant in all regions except the occipital lobe and cerebellum. Age, sex, and cerebrovascular risk factors were not significant predictors of WMH progression. The main predictor of progression was baseline level of WMH. The number of WMH lesions increased by a mean of 1.78, and the progression was mainly accounted for by an increase in very large (>16 mm) lesions. Eight subjects showed a slight decrease in WMH. White matter hyperintensities are progressive in most elderly individuals with an increasing rate of progression as the burden of lesions increases. The rate of progression is greater in deep white matter and in the anterior brain regions. Risk factors for progression are not well understood, and genetic and other environmental factors must be examined. Quantitation of white matter hyperintensities may serve as a surrogate marker of the progression of small vessel disease.

Early results of the posterior saggital anorectoplasty in the treatment of anorectal malformations in Nigerian children

CONTEXT: The ultimate goal of reconstruction in anorectal malformations (ARM) in children, is to create a functional and anatomically aesthetic neoanus. AIMS: To document our experience with the technique of PSARP in ARM and the immediate anatomical and functional outcome SETTINGS AND DESIGN: A retrospective study 39 patients with high and intermediate ARM, managed by the posterior saggital approach, at the Obafemi Awolowo University Teaching Hospital in Ile Ife, Nigeria MATERIALS AND METHODS: Patient's bio-data were collected, as well as, the presentation, investigations, associated malformations, complications, average bowel opening per day and follow up. RESULTS: There were 17 males and 22 females (male: female ratio 1: 1.3). Twenty-three patients (59%) and 15 patients (38.5%), had intermediate and high malformations respectively, while 1(2.5%) had cloaca malformation. The mean age at presentation was 13.9±30.1 month (range 2 day to 15 years), while the mean age at PSARP was 21.6±29.9 months (range 2.5 days to 15 years). 3(7.6%) patients required laparotomy to mobilize the rectal pouch from the abdomen. Mucosal prolapse was the most common significant postoperative problem, occurring in 4(10.3%) patients. The average bowel motion was 3 times daily (range 1 to 8 times per day). CONCLUSIONS: The PSARP is a useful procedure for the correction of ARM, in children in developing countries, even in the absence of muscle stimulators. The immediate anatomical outcome is satisfactory, but functional results are difficult to access because of poor follow up.

How to Investigate Neurovesical Dysfunction in Children With Anorectal Malformations

Neurovesical dysfunction (NVD) is common in children with anorectal malformation (ARM). NVD is mainly related to tethered cord or iatrogenic injury but how to investigate it is still debated. We evaluate the usefulness of routine magnetic resonance imaging (MRI) and urodynamics (UDS) for ARM. A total of 89 children were screened for sacral, spinal or urological anomalies using sacrum x-ray, MRI, renal and spinal ultrasound, uroflowmetry and/or 4-hour voiding observation. UDS was performed in 60 patients with suspected NVD. Mean +/- SD followup was 9.8 +/- 5.2 years. Of the 89 patients 29 presented with urinary tract anomalies. The prevalence of sacral (53 cases) and spinal cord (54) anomalies was no different between patients with low, intermediate and high ARM. Spinal cord tethering was present in 13 patients with a normal sacrum x-ray. NVD was found in 31 of the 89 patients (hyperreflexia 21 and hypo-areflexia 10), and was associated with sacral and spinal anomalies in 23, occult spinal dysraphism without bone lesion in 3 and sacral anomalies in 5. The incidence of NVD was 40% of cases with low and 51% with high ARM. Because tethered cord occurs in children without sacral anomalies as well as in those with low ARM, we recommend evaluation of all patients using MRI. When MRI is positive UDS should be performed. We agree with a previous suggestion to evaluate all males with rectourethral fistula and females with cloaca malformations. Finally we recommend a noninvasive evaluation for all other children and UDS when neurogenic dysfunction is suspected.