Clinical Relevance of Pathological Diagnosis of Hirschsprung's Disease with Acetylcholine-Esterase Histochemistry or Calretinin Immunohistochemistry.

INTRODUCTION: Hirschsprung disease (HD) manifests as a developmental anomaly affecting the enteric nervous system, where there is an absence of ganglion cells in the lower part of the intestine. This deficiency leads to functional blockages within the intestines. HD is usually confirmed or ruled out through rectal biopsy. The identification of any ganglion cells through hematoxylin and eosin (H&E) staining rules out HD. If ganglion cells are absent, further staining with acetylcholine-esterase (AChE) histochemistry or calretinin immunohistochemistry (IHC) forms part of the standard procedure for determining a diagnosis of HD. In 2017, our Institute of Pathology at University Hospital of Heidelberg changed our HD diagnostic procedure from AChE histochemistry to calretinin IHC. In this paper, we report the impact of the diagnostic procedure change on surgical HD therapy procedures and on the clinical outcome of HD patients. METHODS: We conducted a retrospective review of the diagnostic procedures, clinical data, and postoperative progress of 29 patients who underwent surgical treatment for HD in the Department of Pediatric Surgery, University of Heidelberg, between 2012 and 2021. The patient sample was divided into two groups, each covering a treatment period of 5 years. In 2012-2016, HD diagnosis was performed exclusively using AChE histochemistry (AChE group, n = 17). In 2017-2021, HD diagnosis was performed exclusively using calretinin IHC (CR group, n = 12). RESULTS: There were no significant differences between the groups in sex distribution, weeks of gestation, birth weight, length of the aganglionic segment, or associated congenital anomalies. Almost half of the children in the AChE group, twice as many as in the CR group, required an enterostomy before transanal endorectal pull-through procedure (TERPT). In the AChE group, 4 patients (23.5%) required repeat bowel sampling to confirm the diagnosis. Compared to the AChE group, more children in the CR group suffered from constipation post TERPT. DISCUSSION: Elevated AChE expression is linked to hypertrophied extrinsic cholinergic nerve fibers in the aganglionic segment in the majority of patients with HD. The manifestation of increased AChE expression develops over time. Therefore, in neonatal patients with HD, especially those in the first 3 weeks of life, an increase in AChE reaction is not detected. Calretinin IHC reliably identifies the presence or absence of ganglion cells and offers multiple benefits over AChE histochemistry. These include the ability to perform the test on paraffin-embedded tissue sections, a straightforward staining pattern, a clear binary interpretation (negative or positive), cost-effectiveness, and utility regardless of patient age. CONCLUSIONS: The ability of calretinin IHC to diagnose HD early and time-independently prevented repeated intestinal biopsies in our patient population and allowed us to perform a one-stage TERPT in the first months of life, reducing the number of enterostomies and restoring colonic continuity early. Patients undergoing transanal pull-through under the age of 3 months require a close follow-up to detect cases with bowel movement problems.

Pancreatic Surgery in Children: Complex, Safe, and Effective.

OBJECTIVE: The aim of this study was to assess indications for and report outcomes of pancreatic surgery in pediatric patients. BACKGROUND: Indications for pancreatic surgery in children are rare and data on surgical outcomes after pediatric pancreatic surgery are scarce. METHODS: All children who underwent pancreatic surgery at a tertiary hospital specializing in pancreatic surgery between 2003 and 2022 were identified from a prospectively maintained database. Indications, surgical procedures, and perioperative as well as long-term outcomes were analyzed. RESULTS: In total, 73 children with a mean age of 12.8 years (range: 4 mo to 18 y) underwent pancreatic surgery during the observation period. Indications included chronic pancreatitis (n=35), pancreatic tumors (n=27), and pancreatic trauma (n=11). Distal pancreatectomy was the most frequently performed procedure (n=23), followed by pancreatoduodenectomy (n=19), duodenum-preserving pancreatic head resection (n=10), segmental pancreatic resection (n=7), total pancreatectomy (n=3), and others (n=11). Postoperative morbidity occurred in 25 patients (34.2%), including 7 cases (9.6%) with major complications (Clavien-Dindo≥III). There was no postoperative (90-d) mortality. The 5-year overall survival was 90.5%. The 5-year event-free survival of patients with chronic pancreatitis was 85.7%, and 69.0% for patients with pancreatic tumors. CONCLUSION: This is the largest single-center study on pediatric pancreatic surgery in a Western population. Pediatric pancreatic surgery can be performed safely. Centralization in pancreatic centers with high expertise in surgery of adult and pediatric patients is important as it both affords the benefits of pancreatic surgery experience and ensures that surgical management is adapted to the specific needs of children.

Comparison of transection techniques in pediatric major hepatectomy: a matched pair analysis.

BACKGROUND: Evidence on safety and efficacy of different liver transection techniques in pediatric major hepatectomy is completely lacking, as no study has been conducted so far. The use of stapler hepatectomy has never before been reported in children. METHODS: Three liver transection techniques were compared: (1) ultrasonic dissector (CUSA), (2) tissue sealing device (LigaSure™), and (3) stapler hepatectomy. All pediatric hepatectomies performed at a referral center in a 12-year study period were analyzed, patients were pair-matched in a 1:1:1-fashion. Intraoperative weight-adjusted blood loss, operation time, use of inflow occlusion, liver injury (peak-transaminase levels), postoperative complications (CCI), and long-term outcome were compared. RESULTS: Of 57 pediatric liver resections, 15 patients were matched as triples based on age, weight, tumor stage, and extent of resection. Intraoperative blood loss was not significantly different between the groups (p = 0.765). Stapler hepatectomy was associated with significantly shorter operation time (p = 0.028). Neither postoperative death nor bile leakage occurred, and no reoperation due to hemorrhage was needed in any patient. CONCLUSION: This is the first comparison of transection techniques in pediatric liver resection and the first report on stapler hepatectomy in children. All three techniques can be safely applied and may harbor individual advantages in pediatric hepatectomy each.

Learning of Intracorporal Knot Tying in Minimally Invasive Surgery by Video or Expert Instruction.

INTRODUCTION: Minimally invasive surgery skill laboratories are indispensable in training, especially for complex procedural skills such as intracorporal suturing and knot tying (ICKT). However, maintaining a laboratory is expensive, and specially trained teachers are in short supply. During the COVID-19 pandemic, in-person instruction has reduced to almost zero, while model learning via video instruction (VID) has become an integral part of medical education. The aim of this study was to compare the learning effectiveness and efficiency of ICKT by laparoscopically inexperienced medical students through video versus direct expert instruction. MATERIALS AND METHODS: A secondary analysis of two randomized controlled trials was performed. We drew data from students who were trained in ICKT with expert instruction (EXP, n = 30) and from students who were trained via VID, n = 30). A laparoscopic box trainer including laparoscope was used for ICKT. Objective Structured Assessment of Technical Skills (OSATS), knot quality, and total ICKT time were the parameters for the assessment in this study. Proficiency criteria were also defined for these parameters. RESULTS: Students in the EXP group performed significantly better in OSATS-procedure-specific checklist (PSC) and knot quality compared with students in the VID group, with no difference in task time. Of the students who reached the proficiency criteria for OSATS-PSC and knot quality, those in the EXP group required fewer attempts to do so than those in the VID group. Students in both groups improved significantly in all parameters over the first hour of evaluation. CONCLUSION: For the laparoscopically inexperienced, training in ICKT through expert instruction presents an advantage compared with video-based self-study in the form of faster understanding of the procedure and the associated consistent implementation of good knot quality. Both teaching methods significantly improved participants' ICKT skills.

Impact of supplemental anesthesia in preterm infants undergoing inguinal hernia repair under spinal anesthesia : A retrospective analysis.

BACKGROUND: In preterm infants, spinal anesthesia (SpA) is recognized as an alternative to general anesthesia for inguinal hernia repair (IHR); however, some patients require supplemental anesthesia during surgery. The purpose of this study was to investigate the frequency and impact of supplemental anesthesia on perioperative care and adverse respiratory and hemodynamic events. METHODS: A retrospective study of preterm infants undergoing IHR at Heidelberg University Hospital within the first year of life between 2009 and 2018 was carried out. RESULTS: In total, 230 patients (255 surgeries) were investigated. Among 189 procedures completed using SpA 24 patients received supplemental anesthesia. Reasons for supplemental anesthesia included loss of anesthetic effect, returning motor response, and respiratory complications. Compared to SpA alone, no differences were found concerning hemodynamic parameters; however, patients requiring supplemental anesthesia displayed higher rates of postoperative oxygen supplementation and unexpected admission to the intensive care unit. The rate of perioperative apnea was 2.7%. Apneic events exclusively occurred after supplemental anesthesia. Bilateral IHR and duration of surgery were associated with the need for supplemental anesthesia. CONCLUSION: Whereas SpA might be favorable when compared to general anesthesia for IHR, the data indicate that particular caution is required in patients receiving supplemental anesthesia due to the possible risk for adverse respiratory events.

Generating evidence for diagnosis and therapy of RarE LIVEr disease: the RELIVE Initiative for systematic reviews and meta-analyses.

BACKGROUND: Rare liver lesions and diseases have seldomly aroused major interest of researchers. For most guidelines, presumably similar clinical conditions are pooled without detailed investigations of singularities that they present. MAIN TEXT: A multidisciplinary project aiming to establish evidence-based therapies for rare liver diseases has been founded. A series of systematic reviews and meta-analyses will be the starting point for a structured development of guidelines for rare conditions of the liver affecting pediatric and adult populations. The novel approach will be focusing on case reports and small patient series with distinct rare liver diseases without pooling several presumably acceptably similar conditions. Thus, a vital resource of information will be utilized, which has been largely neglected hitherto. CONCLUSION: Highly specific recommendations based on highest available evidence will therefore be developed for specific conditions, advancing the individualized medicine approach for the afflicted patients.

Alveolar macrophages in early stage COPD show functional deviations with properties of impaired immune activation.

Despite its high prevalence, the cellular and molecular mechanisms of chronic obstructive pulmonary disease (COPD) are far from being understood. Here, we determine disease-related changes in cellular and molecular compositions within the alveolar space and peripheral blood of a cohort of COPD patients and controls. Myeloid cells were the largest cellular compartment in the alveolar space with invading monocytes and proliferating macrophages elevated in COPD. Modeling cell-to-cell communication, signaling pathway usage, and transcription factor binding predicts TGF-ß1 to be a major upstream regulator of transcriptional changes in alveolar macrophages of COPD patients. Functionally, macrophages in COPD showed reduced antigen presentation capacity, accumulation of cholesteryl ester, reduced cellular chemotaxis, and mitochondrial dysfunction, reminiscent of impaired immune activation.

Evidence on Indications and Techniques to Increase the Future Liver Remnant in Children Undergoing Extended Hepatectomy: A Systematic Review and Meta-Analysis of Individual Patient Data.

Background: Techniques to increase the future liver remnant (FLR) have fundamentally changed the indications and criteria of resectability in adult liver surgery. In pediatric patients however, these procedures have rarely been applied and the potential benefit or harm as well as suited indications are unclear. Methods: A systematic literature search of MEDLINE, Web of Science, and CENTRAL was conducted. Based on a PRISMA-compliant, predefined methodology, all studies reporting pediatric patients (< 18y) undergoing liver resection with either associating liver partition and portal vein ligation for stages hepatectomy (ALPPS) or preoperative portal vein embolization or ligation (PVE/PVL) were included. Baseline data, periinterventional morbidity, increase of FLR and outcomes were analyzed. Results: 15 studies reporting on 21 pediatric patients with a mean age of 4 years and 7 months (range 1.8 months - 17 years) were included. 12 ALPPS procedures, 8 PVE and 1 PVL were performed. The applied criteria for performing ALPPS or PVE were heterogenous and thresholds for minimally acceptable FLR varied. Mean FLR [% of total liver volume] before the intervention was 23.6% (range 15.0 - 39.3%) in the ALPPS group and 31.4% (range 21.5 - 56.0%) in the PVE group. Mean increase of FLR before stage 2 resection was 69.4% (range 19.0 - 103.8%) for ALPPS and 62.8% (range 25.0 - 108.0%) after PVE. No postoperative death occurred, one early intrahepatic recurrence after an ALPPS procedure was reported. Overall postoperative morbidity was 23.8%. Conclusion: Validated criteria for minimal FLR in pediatric liver resection are lacking and so are clear indications for ALPPS or PVE. In special cases, ALPPS and PVE can be valuable techniques to achieve complete resection of pediatric liver tumors. However, more data are needed, and future studies should focus on a definition and validation of posthepatectomy liver failure as well as the minimally needed FLR in pediatric patients undergoing extended hepatectomy. Systematic Review Registration: [www.clinicaltrials.gov], identifier [PROSPERO 2021 CRD42021274848].

A Systematic Review and Meta-Analysis of Malignant Rhabdoid and Small Cell Undifferentiated Liver Tumors: A Rational for a Uniform Classification.

Background: Rhabdoid liver tumors in children are rare and have a devastating prognosis. Reliable diagnosis and targeted treatment approaches are urgently needed. Immunohistochemical and genetic studies suggest that tumors formerly classified as small cell undifferentiated hepatoblastoma (SCUD) belong to the entity of malignant rhabdoid tumors of the liver (MRTL), in contrast to hepatoblastomas with focal small cell histology (F-SCHB). This may have relevant implications on therapeutic approaches. However, studies with larger cohorts investigating the clinical relevance of the histological and genetic similarities for patients are lacking. Purpose: To analyze possible similarities and differences in patient characteristics, tumor biology, response to treatment, and clinical course of patients with MRTL, SCUD and F-SCHB. Applied therapeutic regimens and prognostic factors are investigated. Methods: A systematic literature search of MEDLINE, Web of Science, and CENTRAL was performed for this PRISMA-compliant systematic review. All studies of patients with MRTL, SCUD and F-SCHB that provided individual patient data were included. Demographic, histological, and clinical characteristics of the three subgroups were compared. Overall survival (OS) was estimated with the Kaplan-Meier method and prognostic factors investigated in a multivariable Cox regression model. Protocol registered: PROSPERO 2021 CRD42021258760. Results: Fifty-six studies with a total of 118 patients were included. The two subgroups MRTL and SCUD did not differ significantly in baseline patient characteristics. However, heterogenous diagnostic and therapeutic algorithms were applied. Large histological and clinical overlap between SCUD and MRTL could be shown. Two-year OS was 22% for MRTL and 13% for SCUD, while it was significantly better in F-SCHD (86%). Chemotherapeutic regimens for hepatoblastoma proved to be ineffective for both SCUD and MRTL, but successful in F-SCHB. Soft tissue sarcoma chemotherapy was associated with significantly better survival for MRTL and SCUD, but was rarely applied in SCUD. Patients who did not undergo surgical tumor resection had a significantly higher risk of death. Conclusions: While F-SCHB is a subtype of HB, SCUD should be classified and treated as a type of MRTL. Surgical tumor resection in combination with intensive, multi-agent chemotherapy is the only chance for cure of these tumors. Targeted therapies are highly needed to improve prognosis. Currently, aggressive regimens including soft tissue sarcoma chemotherapy, extensive resection, radiotherapy or even liver transplantation are the only option for affected children.

The role of liver resection in metastatic nephroblastoma: a systematic review and Meta-regression analysis.

BACKGROUND: The impact of hepatic resection for liver metastases (LM) on the survival of pediatric patients with Wilms' tumor (WT) is unclear. So far, there is a lack of studies investigating the best suited treatment for patients with WTLM, and the role of liver resection has rarely been investigated. Thus, the development of evidence-based guidelines concerning indications of liver resection for WTLM remains difficult. AIM: To investigate the role of surgery in the therapy of WTLM. All available data on liver resections and subgroup outcomes of patients with WTLM are analyzed. Main research question is whether liver resection improves survival rates of patients with WTLM compared to non-surgical treatment. METHODS: A systematic literature search of MEDLINE, Web of Science, and Central provided the basis for this PRISMA-compliant systematic review. For the main analysis (I), all studies reporting on surgical treatment of pediatric WTLM were included. To provide a representative overview of the general outcome of WTLM patients, in analysis II all studies with cohorts of at least five WTLM patients, regardless of the kind of treatment, were reviewed and analyzed. A Multiple meta-regression model was applied to investigate the impact liver resection on overall survival. RESULTS: 14 studies with reports of liver resection for WTLM were found (Analysis I). They included a total of 212 patients with WTLM, of which 93 underwent a liver resection. Most studies had a high risk of bias, and the quality was heterogenous. For the analysis II, eight studies with subgroups of at least five WTLM patients were found. The weighted mean overall survival (OS) of WTLM patients across the studies was 55% (SD 29). A higher rate of liver resection was a significant predictor of better OS in a multiple meta-regression model with 4 covariates (I2 29.43, coefficient 0.819, p = 0.038). CONCLUSIONS: This is the first systematic review on WTLM. Given a lack of suited studies that specifically investigated WTLM, ecological bias was high in our analyses. Generating evidence is complicated in rare pediatric conditions and this study must be viewed in this context. Meta-regression analyses suggest that liver resection may improve survival of patients with WTLM compared to non-surgical treatment. Especially patients with persisting disease after neoadjuvant chemotherapy but also patients with metachronous LM seem to benefit from resection. Complete resection of LM is vital to achieve higher OS. Studies that prospectively investigate the impact of surgery on survival compared to non-surgical treatment for WTLM are highly needed to further close the current evidence gap. STUDY REGISTRATION: PROSPERO 2021 CRD42021249763  https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=249763 .

Quality of Life Improves Following Laparoscopic Hemifundoplication in Neurologically Non-Impaired Children with Gastroesophageal Reflux Disease: A Propensity Score-Matched Analysis.

BACKGROUND: Quality of life (QOL) data following pediatric fundoplication for gastroesophageal reflux disease (GERD) are rare. Present study assessed the QOL in neurologically non-impaired children before and after laparoscopic hemifundoplication (LHF) in comparison to healthy controls. METHODS: PedsQL™ questionnaires assessed data on gastrointestinal symptoms (GIS) and general well-being (GWB) were compared in a propensity score-matched analysis (60 patients' pairs for time-point of surgery and 51 for follow-up). RESULTS: Preoperatively, the LHF group had more GIS (72.2 ± 53.9 vs. 38.8 ± 31.6; p < 0.001) and a lower GWB (16.7 ± 5.5 vs. 23.8 ± 3.5, p < 0.001) compared with controls. Postoperatively, GIS decreased significantly (74.3 ± 52.9 vs. 36.3 ± 33.5; p < 0.001) and the GWB was significantly higher (16.2 ± 6.0 vs. 20.8 ± 5.8; p < 0.001). GIS were similar in the LHF and control groups (39.1 ± 36.4 vs. 40.1 ± 31.0; p = 0.885) but GWB was lower in the LHF group than the control group (20.5 ± 6.3 vs. 23.4 ± 3.9; p = 0.009). CONCLUSIONS: QOL significantly improves after LHF in neurologically non-impaired children.

Biliary Rhabdomyosarcoma in Pediatric Patients: A Systematic Review and Meta-Analysis of Individual Patient Data.

BACKGROUND: The biliary tree is a rare location of pediatric rhabdomyosarcoma. Due to the low incidence, there is a lack of evidence concerning therapeutic guidelines for this tumor location. In particular, the impact of surgery is discussed controversially. PURPOSE: Objective is to generate evidence-based treatment guidelines for pediatric biliary rhabdomyosarcoma (BRMS). All available published data on therapeutic regimens and important prognostic factors are investigated with a focus on the role of surgery. METHODS: A systematic literature search of MEDLINE, Web of Science, and CENTRAL was performed. Patient data were entered individually. Data was pooled and qualitative and quantitative analyses of demographic data, therapy, postoperative/interventional outcomes, relapse, and survival were conducted. In an individual patient data analysis, cox regression was applied to identify key factors predicting the outcome of patients with BRMS. RESULTS: 65 studies met the inclusion criteria, providing data on 176 patients with BRMS. Individual patient data analysis showed a 5-year overall survival and progression-free survival of 51% and 50% for the total study population. For patients treated after 2000, 5-year OS and PFS was 65% and 59%, respectively. Absence of surgical tumor resection was an independent risk factor for death (Hazard ratio 8.9, 95%-CI 1.8-43.6, p = 0.007) and significantly associated with recurrent disease and disease-related death. CONCLUSION: This analysis provides comprehensive information on the largest number of patients hitherto reported in the literature. BRMS is still associated with high morbidity and mortality. Surgical tumor resection is essential for appropriate oncological treatment of BRMS. International cooperation studies are needed to enhance evidence and improve the outcome of this orphan disease. PROTOCOL REGISTRATION: PROSPERO (CRD42021228911) https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021228911.

Establishing a Standardized Measure of Quality in Pediatric Liver Surgery: Definition and Validation of Textbook Outcome With Associated Predictors.

Purpose: To establish comparable reporting of surgical results in pediatric liver surgery, the recently introduced composite outcome measures Textbook Outcome (TO) and Comprehensive Complication Index (CCI) are applied and validated in a pediatric surgery context for the first time. In a representative cohort of pediatric patients undergoing liver resection, predictive factors for TO and CCI are investigated, and outcomes are compared to available literature on surgical outcomes of pediatric liver resection. Methods: All liver resections for patients under 21 years of age performed at the Department of General, Visceral, Transplantation and Pediatric Surgery of the University of Heidelberg between 2009 and 2020 were included in the analysis. Criteria for TO were defined prior to the analysis. Univariate and Multivariate regression was applied to identify factors associated with TO and CCI. Results: Fifty-three pediatric patients underwent liver resections during the observation period. No 30- or 90-day mortality occurred. Twenty-three patients (43.4%) had a TO. CCI and TO showed highly significant correlation (b = -30.33, 95% CI [-37.44; -23.22], p < 0.001). Multivariate analyses revealed significant association between intraoperative blood loss (adjusted for circulating blood volume) and CCI (b = 0.70, 95%CI [0.22; 1.32], p = 0.008) and failure to achieve TO (OR = 0.85, 95%CI [0.69; 0.97], p = 0.048). Conclusion: TO and CCI are suited outcome measures in pediatric surgical studies and offer objective comparability of results. Their application in clinical studies will be a major step forward to establish evidence-based therapies in pediatric surgery. Systematic utilization of TO and CCI can aid in generating comparable studies on surgical techniques and outcomes in pediatric liver resection.

Recurrence rate of infantile hemangioma after oral propranolol therapy.

Oral propranolol is the treatment of choice for infantile hemangiomas. The growth relapse rate following oral propranolol therapy is not well established in the literature. The present study aimed at determining predictors of growth relapse of infantile hemangiomas after discontinuation of oral propranolol therapy. A retrospective analysis was performed of all cases of infantile hemangiomas aged ≤ 12 months undergoing oral propranolol therapy in a 6-year period. Of the 198 cases, regrowth after oral propranolol therapy was observed in 35 patients (18%). Facial hemangiomas showed a higher (p = 0.003) relapse rate as compared with other hemangiomas (27 out of 107 facial cases vs. 8 out of 91 with other location, respectively 25% and 8.8%). Of 35 growth relapses cases, 66% of cases (23 in total, 18 facial and 5 otherwise located hemangiomas) underwent a second cycle of oral propranolol therapy (median length of treatment 3 months, interquartile range 2-3). All cases had a successful outcome, either after a single cycle oral propranolol therapy (163 cases, 82%), or in case of regrowth, after a second therapy cycle (23 cases, 12%) or further conservative management (12 cases, 6%).Conclusion: Facial infantile hemangiomas relapse earlier and more frequently after oral propranolol therapy. We suggest to closely monitor these patients, as a second cycle of propranolol may be indicated. Prolonged oral propranolol therapy might be considered for facial infantile hemangiomas. What is Known: • Oral propranolol is the treatment of choice for infantile hemangiomas. • The growth relapse rate following oral propranolol is not well established. What is New: • The present study points out that facial infantile hemangioma relapse earlier and more frequently after oral propranolol therapy. • Patients with facial infantile hemangiomas should be monitored after propranolol therapy discontinuation.

A complementary study approach unravels novel players in the pathoetiology of Hirschsprung disease.

Hirschsprung disease (HSCR, OMIM 142623) involves congenital intestinal obstruction caused by dysfunction of neural crest cells and their progeny during enteric nervous system (ENS) development. HSCR is a multifactorial disorder; pathogenetic variants accounting for disease phenotype are identified only in a minority of cases, and the identification of novel disease-relevant genes remains challenging. In order to identify and to validate a potential disease-causing relevance of novel HSCR candidate genes, we established a complementary study approach, combining whole exome sequencing (WES) with transcriptome analysis of murine embryonic ENS-related tissues, literature and database searches, in silico network analyses, and functional readouts using candidate gene-specific genome-edited cell clones. WES datasets of two patients with HSCR and their non-affected parents were analysed, and four novel HSCR candidate genes could be identified: ATP7A, SREBF1, ABCD1 and PIAS2. Further rare variants in these genes were identified in additional HSCR patients, suggesting disease relevance. Transcriptomics revealed that these genes are expressed in embryonic and fetal gastrointestinal tissues. Knockout of these genes in neuronal cells demonstrated impaired cell differentiation, proliferation and/or survival. Our approach identified and validated candidate HSCR genes and provided further insight into the underlying pathomechanisms of HSCR.

Scalable Prediction of Acute Myeloid Leukemia Using High-Dimensional Machine Learning and Blood Transcriptomics.

Acute myeloid leukemia (AML) is a severe, mostly fatal hematopoietic malignancy. We were interested in whether transcriptomic-based machine learning could predict AML status without requiring expert input. Using 12,029 samples from 105 different studies, we present a large-scale study of machine learning-based prediction of AML in which we address key questions relating to the combination of machine learning and transcriptomics and their practical use. We find data-driven, high-dimensional approaches-in which multivariate signatures are learned directly from genome-wide data with no prior knowledge-to be accurate and robust. Importantly, these approaches are highly scalable with low marginal cost, essentially matching human expert annotation in a near-automated workflow. Our results support the notion that transcriptomics combined with machine learning could be used as part of an integrated -omics approach wherein risk prediction, differential diagnosis, and subclassification of AML are achieved by genomics while diagnosis could be assisted by transcriptomic-based machine learning.

A Population of Radio-Resistant Macrophages in the Deep Myenteric Plexus Contributes to Postoperative Ileus Via Toll-Like Receptor 3 Signaling.

Postoperative ileus (POI) is triggered by an innate immune response in the muscularis externa (ME) and is accompanied by bacterial translocation. Bacteria can trigger an innate immune response via toll-like receptor (TLR) activation, but the latter's contribution to POI has been disproved for several TLRs, including TLR2 and TLR4. Herein we investigated the role of double-stranded RNA detection via TLR3 and TIR-domain-containing adapter-inducing interferon-ß (TRIF) signaling pathway in POI. POI was induced by small bowel intestinal manipulation in wt, TRIF-/-, TLR3-/-, type I interferon receptor-/- and interferon-ß reporter mice, all on C57BL/6 background, and POI severity was quantified by gene expression analysis, gastrointestinal transit and leukocyte extravasation into the ME. TRIF/TLR3 deficiency reduced postoperative ME inflammation and prevented POI. With bone marrow transplantation, RNA-sequencing, flow cytometry and immunohistochemistry we revealed a distinct TLR3-expressing radio-resistant MHCIIhiCX3CR1- IBA-1+ resident macrophage population within the deep myenteric plexus. TLR3 deficiency in these cells, but not in MHCIIhiCX3CR1+ macrophages, reduced cytokine expression in POI. While this might not be an exclusive macrophage-privileged pathway, the TLR3/TRIF axis contributes to proinflammatory cytokine production in MHCIIhiCX3CR1- IBA-1+ macrophages during POI. Deficiency in TLR3/TRIF protects mice from POI. These data suggest that TLR3 antagonism may prevent POI in humans.

Food fear, quick satiety and vomiting in a 16 years old girl: It's bulimia, or maybe not ? A case report of Wilkie's syndrome (superior mesenteric artery syndrome).

INTRODUCTION: Wilkie's syndrome (WS), also known as superior mesenteric artery syndrome, is a rare clinical entity caused by compression of the horizontal (third) part of the duodenum between the superior mesenteric artery and the abdominal aorta leading to duodenal obstruction. PRESENTATION OF CASE: We report a case of a 16 years girl with long-term history of spontaneous vomiting and self-induced vomiting, also suffering from recurrent retrosternal pain, weight loss and thus reduced quality of life. Contrast intestinal series showed a large axial hernia which was laparoscopically reduced and treated by hiatoplasty and anterior hemifundoplication. After initial relief, recurrent postprandial nausea and vomiting reoccurred 4 weeks postoperatively. Abdominal MRI study revealed findings compatible with WS. After endoscopic exclusion of an anatomical duodenal lumen stenosis, she was successfully treated by duodeno-jejunostomy with a favorable outcome. DISCUSSION: WS might be hidden behind presumably more evident diagnoses such as bulimia, significant axial hernia and gastro-esophageal reflux disease in patients with recurred vomiting, abdominal pain and weight loss. CONCLUSION: The rare clinical entity of a WS necessitates a targeted diagnostic evaluation and therapy. Clinical details, diagnostic studies and treatment are discussed here.

Postnatal human enteric neurospheres show a remarkable molecular complexity.

BACKGROUND: The enteric nervous system (ENS), a complex network of neurons and glial cells, coordinates major gastrointestinal functions. Impaired development or secondary aberrations cause severe enteric neuropathies. Neural crest-derived stem cells as well as enteric neuronal progenitor cells, which form enteric neurospheres, represent a promising tool to unravel molecular pathomechanisms and to develop novel therapy options. However, so far little is known about the detailed cellular composition and the proportional distribution of enteric neurospheres. Comprehensive knowledge will not only be essential for basic research but also for prospective cell replacement therapies to restore or to improve enteric neuronal dysfunction. METHODS: Human enteric neurospheres were generated from three individuals with varying age. For detailed molecular characterization, nCounter target gene expression analyses focusing on stem, progenitor, neuronal, glial, muscular, and epithelial cell markers were performed. Corresponding archived paraffin-embedded individuals' specimens were analyzed accordingly. KEY RESULTS: Our data revealed a remarkable molecular complexity of enteric neurospheres and archived specimens. Amongst the expression of multipotent stem cell, progenitor cell, neuronal, glial, muscle and epithelial cell markers, moderate levels for the pluripotency marker POU5F1 were observed. Furthermore, besides the interindividual variability, we identified highly distinct intraindividual expression profiles. CONCLUSIONS & INFERENCES: Our results emphasize the assessment of molecular signatures to be essential for standardized use, optimization of experimental approaches, and elimination of potential risk factors, as the formation of tumors. Our study pipeline may serve as a blueprint implemented into the characterization procedure of enteric neurospheres for various future applications.

Simultaneous Serial Transverse Enteroplasty (STEP) in Size Mismatch Small Bowel Transplantations.

BACKGROUND: Small bowel transplantation (SBTX) in children receiving larger grafts from adults can be challenging because of size mismatch. The aim of the present study was to assess whether a simultaneous serial transverse enteroplasty (STEP) can address the problem of size mismatch. METHODS: Three different size ratio groups between donors and recipients were compared in a porcine model with a 14-day follow-up. The groups were size matched, size mismatched (1:3.8 weight ratio), and size mismatched + STEP (each n = 8). RESULTS: It was technically feasible to simultaneously perform a STEP and SBTX of a mismatched intestinal segment. The postoperative clinical course was uneventful. No signs of bleeding, leakage, stenosis, or ileus were observed and the intestinal segment was well perfused at relaparotomy. Body weight decreased in all groups, but the percentage decrease was lowest in the mismatched + STEP group. Vital enterocyte masses were similar in all the groups (citrulline levels) and the nutritional status was best in the STEP group (transferrin levels, p = 0.04). CONCLUSIONS: We have demonstrated that a simultaneous STEP and SBTX procedure is technically feasible and clinically useful in overcoming the challenges associated with size mismatched SBTX. Our short-term findings justify further investigation in a larger series to elucidate the long-term outcomes of this procedure.