Matrix Metalloproteinase-7 and Osteopontin Serum Levels as Biomarkers for Biliary Atresia.

OBJECTIVES: Matrix metallopeptidase-7 (MMP-7) and osteopontin (OPN) are important components in the pathophysiology of fibrosis in biliary atresia (BA). There has been much recent interest in MMP-7 serum level in the diagnosis of BA. We aimed to assess the diagnostic accuracy and prognostic value of both MMP-7 and OPN in a Western BA study. METHODS: Diagnostic value was assessed by comparison of serum MMP-7 and OPN levels in infants with BA and age-matched cholestatic controls. Prognostic value was assessed through subsequent clearance of jaundice (COJ) and need for liver transplantation (LT). RESULTS: Serum was assessed from 32 BA and 27 controls. Median MMP-7 was higher in BA (96.4 vs 35 ng/mL; P < 0.0001) with an optimal cut-off value of 69 ng/mL. Sensitivity and specificity was 68% and 93%, respectively [negative predictive value (NPV) = 71%]. Similarly, median OPN was higher in BA (1952 vs 1457 ng/mL; P = 0.0001) and an optimal cut-off of 1611 ng/mL. Sensitivity and specificity was 84% and 78%, respectively (NPV = 81%). MMP-7 level correlated positively with Ishak liver fibrosis score (r = 0.27, P = 0.04). Neither MMP-7 (70 vs 100 ng/mL; P = 0.2) nor OPN (1969 vs 1939 ng/mL; P = 0.3) were predictive of COJ, or need for LT (99 vs 79 ng/mL; P = 0.7, and 1981 vs 1899 ng/mL; P = 0.2), respectively. CONCLUSIONS: MMP-7 and OPN may have contributory value in the diagnosis of BA, but remain far of the "gold standard" role. Much more prospective data are required and collaborative multi-center initiatives should be the next logical steps.

Intestinal Bowel Lengthening within the First 6 Months of Life: Institutional Experience and Review of the Literature.

Background: Management of short bowel syndrome in children has been surrounded by much debate with timing of the lengthening procedure still controversial. Early bowel lengthening procedure (EBLP) has been defined as any bowel lengthening procedure performed before 6 months of age. The purpose of this paper is to report the institutional experience in EBLP and to review the literature on this subject to identify common indications. Methods: An institutional retrospective analysis of all the intestinal lengthening procedures was performed. Furthermore, an Ovid/Embase search regarding children who underwent bowel lengthening in the past 38 years was conducted. Primary diagnosis, age at procedure, type of procedure, indication, and outcome were analyzed. Results: Ten EBLP were performed in Manchester from 2006 to 2017. Median age at surgery was 121 days (102-140), preoperative small bowel (SB) length was 30 cm (20-49) while postoperative SB length was 54 cm (40-70), with a median increased bowel length of 80%. Ninety-seven papers were reviewed, with more than 399 lengthening procedures performed. Twenty-nine papers matched criteria with more than 60 EBLP were observed of which 10 were performed in a single center from 2006 to 2017. EBLP was performed due to SB atresia, to excessive bowel dilatation or failure to enteral feeds, at a median age of 60 days (1-90). Serial transverse enteroplasty was the most frequent procedure used lengthening the bowel from 40 cm (29-62.5) to 63 cm (49-85), with a median increased bowel length of 57%. Conclusions: This study confirms that no clear consensus on indication or timing to perform early SB lengthening is reported. According to the gathered data, EBLP should be considered, only in cases of actual necessity after review of qualified intestinal failure center.

TNAP limits TGF-ß-dependent cardiac and skeletal muscle fibrosis by inactivating the SMAD2/3 transcription factors.

Fibrosis is associated with almost all forms of chronic cardiac and skeletal muscle diseases. The accumulation of extracellular matrix impairs the contractility of muscle cells contributing to organ failure. Transforming growth factor ß (TGF-ß) plays a pivotal role in fibrosis, activating pro-fibrotic gene programmes via phosphorylation of SMAD2/3 transcription factors. However, the mechanisms that control de-phosphorylation of SMAD2 and SMAD3 (SMAD2/3) have remained poorly characterized. Here, we show that tissue non-specific alkaline phosphatase (TNAP, also known as ALPL) is highly upregulated in hypertrophic hearts and in dystrophic skeletal muscles, and that the abrogation of TGF-ß signalling in TNAP-positive cells reduces vascular and interstitial fibrosis. We show that TNAP colocalizes and interacts with SMAD2. The TNAP inhibitor MLS-0038949 increases SMAD2/3 phosphorylation, while TNAP overexpression reduces SMAD2/3 phosphorylation and the expression of downstream fibrotic genes. Overall our data demonstrate that TNAP negatively regulates TGF-ß signalling and likely represents a mechanism to limit fibrosis.

Transgelin-expressing myofibroblasts orchestrate ventral midline closure through TGFß signalling.

Ventral body wall (VBW) defects are among the most common congenital malformations, yet their embryonic origin and underlying molecular mechanisms remain poorly characterised. Transforming growth factor beta (TGFß) signalling is essential for VBW closure, but the responding cells are not known. Here, we identify in mouse a population of migratory myofibroblasts at the leading edge of the closing VBW that express the actin-binding protein transgelin (TAGLN) and TGFß receptor (TGFßR). These cells respond to a temporally regulated TGFß2 gradient originating from the epithelium of the primary body wall. Targeted elimination of TGFßR2 in TAGLN+ cells impairs midline closure and prevents the correct subsequent patterning of the musculature and skeletal components. Remarkably, deletion of Tgfbr2 in myogenic or chondrogenic progenitor cells does not manifest in midline defects. Our results indicate a pivotal significance of VBW myofibroblasts in orchestrating ventral midline closure by mediating the response to the TGFß gradient. Altogether, our data enable us to distinguish highly regulated epithelial-mesenchymal signalling and successive cellular migration events in VBW closure that explain early morphological changes underlying the development of congenital VBW defects.

Distinct Cellular Mechanisms Underlie Smooth Muscle Turnover in Vascular Development and Repair.

RATIONALE: Vascular smooth muscle turnover has important implications for blood vessel repair and for the development of cardiovascular diseases, yet lack of specific transgenic animal models has prevented it's in vivo analysis. OBJECTIVE: The objective of this study was to characterize the dynamics and mechanisms of vascular smooth muscle turnover from the earliest stages of embryonic development to arterial repair in the adult. METHODS AND RESULTS: We show that CD146 is transiently expressed in vascular smooth muscle development. By using CRISPR-Cas9 genome editing and in vitro smooth muscle differentiation assay, we demonstrate that CD146 regulates the balance between proliferation and differentiation. We developed a triple-transgenic mouse model to map the fate of NG2+CD146+ immature smooth muscle cells. A series of pulse-chase experiments revealed that the origin of aortic vascular smooth muscle cells can be traced back to progenitor cells that reside in the wall of the dorsal aorta of the embryo at E10.5. A distinct population of CD146+ smooth muscle progenitor cells emerges during embryonic development and is maintained postnatally at arterial branch sites. To characterize the contribution of different cell types to arterial repair, we used 2 injury models. In limited wire-induced injury response, existing smooth muscle cells are the primary contributors to neointima formation. In contrast, microanastomosis leads to early smooth muscle death and subsequent colonization of the vascular wall by proliferative adventitial cells that contribute to the repair. CONCLUSIONS: Extensive proliferation of immature smooth muscle cells in the primitive embryonic dorsal aorta establishes the long-lived lineages of smooth muscle cells that make up the wall of the adult aorta. A discrete population of smooth muscle cells forms in the embryo and is postnatally sustained at arterial branch sites. In response to arterial injuries, existing smooth muscle cells give rise to neointima, but on extensive damage, they are replaced by adventitial cells.

Surgical and Endoscopic Intervention for Chronic Pancreatitis in Children: The Kings College Hospital Experience.

Paediatric chronic pancreatitis (CP) is a rare and debilitating pathology that often requires invasive diagnostics and therapeutic interventions either to address a primary cause such as a pancreaticobiliary malunion or to deal with secondary complications such as chronic pain. Endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) are two endoscopic modalities that have an established diagnostic role in paediatric CP, and their therapeutic utilisation is increasing in popularity. Surgical decompression of the obstructed and dilated pancreatic duct plays a role in alleviating pancreatic duct hypertension, a common association in CP. Surgery equally has a role in certain anatomical abnormalities of the pancreaticobiliary draining system, or occasionally in some CP complications such as drainage of a symptomatic pancreatic pseudocyst.

Standardising the elusive diagnosis of NEC in the premature infant - A practical score.

OBJECTIVE: The perceived risk of necrotising enterocolitis (NEC) can result in overtreatment of the otherwise adapting preterm neonate. We aim to develop an assessment tool to aid the decision making in the management of preterm neonates at risk of NEC. METHOD: An evidence-based assessment tool was designed bringing together clinical, laboratory and radiological signs commonly associated with NEC. A numerical score was awarded for each sign, with those more specific to NEC being graded higher. A multi-centre validation was conducted of the proposed assessment tool over three tertiary neonatal units. RESULTS: A total of 125 patients were included, 53 (42.4 %) with a final diagnosis of NEC and 72 (57.6 %) with an alternative diagnosis. The NEC group had a significantly higher total score compared to the non-NEC group; 15(2-28) vs. 4(1-9) (p ≤ 0.0001). In ROC analysis, using a cut-off of eight, the assessment tool gave a sensitivity of 92.3 % and a specificity of 90.4 % for identifying NEC compared to an alternative diagnosis. CONCLUSION: This comprehensive scoring system encourages a full assessment of the infant before deciding on withholding feeds, starting antibiotics, and transferring to a surgical centre. It is a safe objective measure to support a diagnosis of NEC in the presence of certain clinical signs.

Cardiac-associated biliary atresia (CABA): a prognostic subgroup.

OBJECTIVES: To describe the range of concurrent cardiac malformations in biliary atresia (BA) while providing a functional framework of risk. METHODS: Demographic and variables were collected from a prospectively maintained single-centre database. Infants were grouped according to a cardiac functional framework (A=acyanotic, B=cyanotic and C=insignificant shunt). Primary outcome was set as clearance of jaundice (bilirubin ≤20 µmol/L) following Kasai portoenterostomy (KPE). Native liver survival and overall actuarial survival were compared with a date-matched control infant with BA (n=77). P value <0.05 was regarded as significant. RESULTS: 524 infants with histologically confirmed BA were treated between January 1999 and December 2018, 37 (7%) had a concurrent cardiac anomaly (A: n=23 (62%), B: n=10 (27%), C: n=4 (11%)). Infants with biliary atresia splenic malformation (BASM) or cat-eye syndrome (CES) contributed over half of the cases (21/37; 57%).Overall, 20 (54%) infants cleared jaundice (vs 50/77 (65%) controls; p=0.2), but with higher mortality compared with the non-cardiac controls (15/37 (40%) vs 3/77 (4%); HR 15.5 (95% CI 5.5 to 43.4); p<0.00001). Infants requiring cardiac intervention in the first year of life (n=15) were more likely to clear jaundice (6/7 vs 2/8; p=0.04) and had a trend towards higher survival (6/7 vs 3/8; p=0.1) when KPE followed cardiac surgery. Yet, the type of cardiac pathology did not impact clearance of jaundice or mortality. CONCLUSION: We propose the term cardiac-associated biliary atresia (CABA) as a high-risk group. We believe that restorative cardiac surgery should precede KPE wherever possible to improve outcome.

Variations in the Detection of Anorectal Anomalies at Birth among European Cities.

INTRODUCTION: The diagnosis of anorectal malformations (ARMs) is made at birth by perineal examination of the newborn, yet small series reported late diagnosis in almost 13%. No large series to date have looked into the magnitude of missed ARM cases in the neonatal period across Europe. This study aimed to define the rate of missed ARM at birth across four United Kingdom and European Union centers. MATERIALS AND METHODS: All ARM cases treated at two United Kingdom tertiary centers in the past 15 years were compared with two tertiary European centers. Demographic and relevant clinical data were collected. Late diagnosis was defined as any diagnosis made after discharge from the birth unit. Factors associated with late diagnosis were explored with descriptive statistics. RESULTS: Across the four centers, 117/1,350, 8.7% were sent home from the birth unit without recognizing the anorectal anomaly. Missed cases showed a slight female predominance (1.3:1), and the majority (113/117, 96.5%) were of the low anomaly with a fistula to the perineum. The rate of missed ARM cases was significantly higher in the United Kingdom centers combined (74/415, 17.8%) compared with those in the European Union (43/935, 4.6%) (p < 0.00001), and this was independent of individual center and year of birth. CONCLUSION: Significant variation exists between the United Kingdom and other European countries in the detection of ARM at birth. We recommend raising the awareness of accurate perineal examination at the time of newborn physical examination. We feel this highlights an urgent need for a national initiative to assess and address the timely diagnosis of ARM in the United Kingdom.

Institutional Experience with Spiral Intestinal Lengthening and Tailoring.

AIM: The aim of this study was to report our initial experience using spiral intestinal lengthening and tailoring (SILT) technique in selected cases of short bowel syndrome (SBS). MATERIALS AND METHODS: We analyzed all cases of SBS underwent SILT in our unit since the introduction of the procedure in 2012. We retrospectively analyzed patients' demographics, pre- and postprocedure bowel length, surgical complications, and postoperative parenteral nutrition (PN) requirements. Data were compared using independent samples, Mann-Whitney's U-test. RESULTS: Five children with SBS underwent SILT between 2012 and 2017. Median age at procedure was 8.3 months (4.5-16). Preoperative small bowel length measured a median of 22 cm (17.5-50) with a median diameter of 4 cm (3.5-4.6). SILT allowed a median increase in length of 56% (10-15 cm; p = 0.03) and tailoring of the dilated segment providing a reduction in diameter of 50% (4.3-2.1 cm; p = 0.01). No major complications related to SILT were encountered and none of the children required further surgical intervention following a median follow-up of 26 months (14.5-41). Interestingly, we observed a significant reduction of PN requirement at 6 months (p = 0.008) associated with liver function preservation during the follow-up period. CONCLUSION: In our experience, SILT is a promising adjunct in the surgical management of SBS. It can be used to tailor and lengthen mildly dilated segments of the bowel where other procedures are technically challenging, with a view to reduce the risk of intestinal failure associated liver disease and thereby improving chances for quality survival. Further studies are needed to investigate long-term outcomes of SILT in pediatric SBS.

Total esophagogastric dissociation (TEGD): Lessons from two decades of experience.

BACKGROUND: Total esophagogastric dissociation (TEGD) has been performed in our institution since 1994, predating its published description by Bianchi in 1997. Originally it was considered a rescue procedure when conventional antireflux surgery failed. Recently TEGD has been considered a viable primary option for the treatment of gastroesophageal reflux disease (GERD) in severely neurological impaired (NI) patients. We describe our institution's experience of TEGD in this selected cohort of patients. METHODS: An institutional retrospective review was performed detailing our total experience of open TEGD between 1994 and 2015 in severely neurologically impaired (NI) patients. Demographic, complications, and outcome were analyzed. RESULTS: Sixty-six NI patients underwent TEGD between 1994 and 2015 (39 female). Primary TEGD was performed in forty-nine patients (74.2%), while the remainder were rescue procedures following the failure of previous antireflux surgery. In 98% of cases no recurrence of clinically significant reflux was reported. The mean hospital length of stay was 10.2 days. There were sixteen reported complications in twelve patients representing 18.2% of the cohort. One death was attributable to the procedure (1.5%). Median follow-up was 31.6 months (range, 1.3-137.9 months). CONCLUSION: TEGD appears to be a valid surgical option to treat severe GERD in severely neurologically impaired children, both as a primary procedure and as a rescue procedure following failure of anti-reflux surgery. Further studies comparing TEGD versus laparoscopic fundoplication are desirable to understand which of these procedures can be the most effective in this compromised group of patients. TYPE OF STUDY: Retrospective study Level of evidence: IV.

Abrogation of TGF-beta signalling in TAGLN expressing cells recapitulates Pentalogy of Cantrell in the mouse.

Pentalogy of Cantrell (PC) is a rare multi-organ congenital anomaly that impedes ventral body wall closure and results in diaphragmatic hernia, intra- and pericardial defects. The underlying cellular and molecular changes that lead to these severe developmental defects have remained unknown largely due to the lack of representative animal models. Here we provide in depth characterization of a mouse model with conditional ablation of TGFßRII in Transgelin (Tagln) expressing cells. We show that Tagln is transiently expressed in a variety of cells that participate in the embryonic development and patterning of ventral structures. Genetic ablation of TGFßRII in these cells leads to ventral midline closure defect, diaphragmatic hernia, dilated cardiac outflow tract and aberrant cardiac septation, providing a reliable model to study the morphological changes leading to PC. We show that myogenisis in the diaphragm is independent of TGFß and the diaphragmatic hernia arises from fibroblast-specific migration defect. In the dorsal body wall Tagln expression is initiated after the closure process, revealing a remarkable difference between ventral and dorsal body walls development. Our study demonstrates the use of micro-CT scanning to obtain a 3-dimensional high-resolution overview of embryonic anomalies and provides the first mechanistic insight into the development of PC.