Live-attenuated vaccination for measles, mumps, and rubella in pediatric liver transplantation

BACKGROUND

Infections are a serious short- and long-term problem after pediatric organ transplantation. In immunocompromised patients, they can lead to transplant rejection or a severe course with a sometimes fatal outcome. Vaccination is an appropriate means of reducing morbidity and mortality caused by vaccine-preventable diseases. Unfortunately, due to the disease or its course, it is not always possible to establish adequate vaccine protection against live-attenuated viral vaccines (LAVVs) prior to transplantation. LAVVs such as measles, mumps, and rubella (MMR) are still contraindicated in solid organ transplant recipients receiving immunosuppressive therapy (IST), thus creating a dilemma.

AIM

This review discusses whether, when, and how live-attenuated MMR vaccines can be administered effectively and safely to pediatric liver transplant recipients based on the available data.

MATERIAL AND METHODS

We searched PubMed for literature on live-attenuated MMR vaccination in pediatric liver transplantation (LT).

RESULTS

Nine prospective observational studies and three retrospective case series were identified in which at least 833 doses of measles vaccine were administered to 716 liver transplant children receiving IST. In these selected patients, MMR vaccination was well tolerated and no serious adverse reactions to the vaccine were observed. In addition, an immune response to the vaccine was demonstrated in patients receiving IST.

CONCLUSION

Due to inadequate vaccine protection in this high-risk group, maximum efforts must be made to ensure full immunization. MMR vaccination could also be considered for unprotected patients after LT receiving IST following an individual risk assessment, as severe harm from live vaccines after liver transplantation has been reported only very rarely. To this end, it is important to establish standardized and simple criteria for the selection of suitable patients and the administration of the MMR vaccine to ensure safe use.

Epidemiology, clinical features and management of autoimmune hepatitis in Switzerland: a retrospective and prospective cohort study

BACKGROUND AND AIMS

The Swiss Autoimmune Hepatitis Cohort Study is a nationwide registry, initiated in 2017, that collects retrospective and prospective clinical data and biological samples from patients of all ages with autoimmune hepatitis treated at Swiss hepatology centres. Here, we report the analysis of the first 5 years of registry data.

RESULTS

A total of 291 patients with autoimmune hepatitis have been enrolled, 30 of whom were diagnosed before 18 years of age and composed the paediatric cohort. Paediatric cohort: median age at diagnosis 12.5 years (range 1-17, interquartile range (IQR) 8-15), 16 (53%) girls, 6 (32%) with type 2 autoimmune hepatitis, 8 (27%) with autoimmune sclerosing cholangitis, 1 with primary biliary cholangitis variant syndrome, 4 (15%) with inflammatory bowel disease and 10 (41%) with advanced liver fibrosis at diagnosis. Adult cohort: median age at diagnosis 54 years (range 42-64, IQR 18-81), 185 (71%) women, 51 (20%) with primary biliary cholangitis variant syndrome, 22 (8%) with primary sclerosing cholangitis variant syndrome, 9 (4%) with inflammatory bowel disease and 66 (32%) with advanced liver fibrosis at diagnosis. The median follow-up time for the entire cohort was 5.2 years (IQR 3-9.3 years). Treatment in children: 29 (97%) children were initially treated with corticosteroids, 28 of whom received combination treatment with azathioprine. Budesonide was used in four children, all in combination with azathioprine. Mycophenolate mofetil was used in five children, all of whom had previously received corticosteroids and thiopurine. Treatment in adults (data available for 228 patients): 219 (96%) were treated with corticosteroids, mostly in combination with azathioprine. Predniso(lo)ne was the corticosteroid used in three-quarters of patients; the other patients received budesonide. A total of 78 (33%) patients received mycophenolate mofetil, 62 of whom had previously been treated with azathioprine. Complete biochemical response was achieved in 13 of 19 (68%) children and 137 of 182 (75%) adults with available follow-up data. All children were alive at the last follow-up, and none had undergone liver transplantation. Five (2%) adults underwent liver transplantation, two of whom had a fulminant presentation. Four (2%) adults with autoimmune hepatitis died (two from liver-associated causes).

CONCLUSION

Patients with autoimmune hepatitis in Switzerland had clinical features similar to those in other cohorts. The proportion of patients diagnosed with primary biliary cholangitis variant syndrome was higher than expected. Autoimmune hepatitis was managed according to guidelines, except for the use of budesonide in a small proportion of paediatric patients. The outcomes were excellent, but the findings must be confirmed over a longer follow-up period.

Microbiome analysis and fecal microbiota transfer in pediatric gastroenterology - a structured online survey in German-speaking countries

PURPOSE

To assess the current attitude and the status quo towards the use of microbiome analysis and fecal microbiota transfer (FMT) in pediatric patients in German-speaking pediatric gastroenterology centers.

METHODS

A structured online survey among all certified facilities of the German-speaking society of pediatric gastroenterology and nutrition (GPGE) was conducted from November 01, 2020, until March 30, 2021.

RESULTS

A total of 71 centers were included in the analysis. Twenty-two centers (31.0%) use diagnostic microbiome analysis, but only a few perform analysis frequently (2; 2.8%) or regularly (1; 1.4%). Eleven centers (15.5%) have performed FMT as a therapeutic approach. Most of these centers use individual in-house donor screening programs (61.5%). One-third (33.8%) of centers rate the therapeutic impact of FMT as high or moderate. More than two-thirds (69.0%) of all participants are willing to participate in studies assessing the therapeutic effect of FMT.

CONCLUSIONS

Guidelines for microbiome analyses and FMT in pediatric patients and clinical studies investigating their benefits are absolutely necessary to improve the patient-centered care in pediatric gastroenterology. The long-term and successful establishment of pediatric FMT centers with standardized procedures for patient selection, donor screening, application route, volume, and frequency of use is highly required to obtain a safe therapy.

How to Respond to Misinformation From the Anti-Vaccine Movement

Vaccines are doubtlessly one of the most crucial life-saving medical interventions to date. However, perplexingly, they court more public controversy than their objectively excellent safety profile warrants. While doubts about the safety of vaccines, as well as opposition to vaccine policies, can be traced back at least to the mid-19th century, the modern anti-vaccine movement has come in 3 distinct waves, or generations, each precipitating around distinct key events. Here, we describe the first 2 generations and trace the origins of an emerging third generation anti-vaccine movement. Currently, this third generation is an integral part of the larger anti-COVID movement and in this more libertarian environment propagates the idea of individualism superseding the responsibility for community health. We highlight the need for a better science education of the young, as well as the general public to further enhance overall science literacy and suggests strategies to achieve these goals.

Pediatric endoscopy training across Europe: a survey of the ESPGHAN National Societies Network 2016-2019

Background and study aims  The ability to perform endoscopy procedures safely and effectively is a key aspect of quality clinical care in Pediatric Gastroenterology, Hepatology and Nutrition (PGHN). The aim of this survey, which was part of a global survey on PGHN training in Europe, was to assess endoscopy training opportunities provided across Europe. Methods  Responses to standardized questions related to endoscopy training were collected from training centers across Europe through the presidents/representatives of the European Society for Paediatric Gastroenterology, Hepatology and Nutrition National Societies from June 2016 to December 2019. Results  A total of 100 training centers from 19 countries participated in the survey. In 57 centers, the endoscopy suit was attached to the PGHN center, while in 23, pediatric endoscopies were performed in adult endoscopy facilities. Ninety percent of centers reported the availability of specialized endoscopy nurses and 96 % of pediatric anesthetists. Pediatric endoscopies were performed by PGHN specialists in 55 centers, while 31 centers reported the involvement of an adult endoscopist and 14 of a pediatric surgeon. Dividing the number of procedures performed at the training center by the number of trainees, ≤ 20 upper, lower, or therapeutic endoscopies per trainee per year were reported by 0 %, 23 %, and 56 % of centers, respectively, whereas ≤ 5 wireless capsule endoscopies per trainee per year by 75 %. Only one country (United Kingdom) required separate certification of competency in endoscopy. Conclusions  Differences and deficiencies in infrastructure, staffing, and procedural volume, as well as in endoscopy competency assessment and certification, were identified among European PGHN training centers limiting training opportunities in pediatric endoscopy.

Training in Paediatric Clinical Nutrition Across Europe: A Survey of the National Societies Network (2016-2019) of the European Society for Paediatric Gastroenterology, Hepatology and Nutrition

OBJECTIVES/BACKGROUND

Disease-related malnutrition is common in patients with chronic diseases and has detrimental effects, therefore, skills in nutrition care are essential core competencies for paediatric digestive medicine. The aim of this survey, conducted as part of a global survey of paediatric gastroenterology, hepatology and nutrition (PGHN) training in Europe, was to assess nutrition care-related infrastructure, staff, and patient volumes in European PGHN training centres.

METHODS

Standardized questionnaires related to clinical nutrition (CN) care were completed by representatives of European PGHN training centres between June 2016 and December 2019.

RESULTS

One hundred training centres from 17 European countries, Turkey, and Israel participated in the survey. Dedicated CN clinics exist in 66% of the centres, with fulltime and part-time CN specialists in 66% and 42%, respectively. Home tube feeding (HTF) andhome parenteral nutrition (HPN) programmes are in place in 95% and 77% of centres, respectively. Twenty-four percent of centres do not have a dedicated dietitian and 55% do not have a dedicated pharmacist attached to the training centre. Even the largest centres with >5000 outpatients reported that 25% and 50%, respectively do not have a dedicated dietitian or pharmacist. Low patient numbers on HTF and HPN of <5 annually are reported by 13% and 43% of centres, respectively.

CONCLUSIONS

The survey shows clear differences and deficits in Clinical Nutrition training infrastructure, including staff and patient volumes, in European PGHN training centres, leading to large differences and limitations in training opportunities in Clinical Nutrition.

[Paediatric gastroenterological and hepatological care in Germany: results of a nationwide survey]

Einleitung Kinder und Jugendliche mit chronischen Magen-, Darm-, Pankreas-, und Lebererkrankungen benötigen eine altersgerechte und qualifizierte Behandlung. Anhand einer repräsentativen Umfrage wird die strukturelle und personelle ambulante und stationäre Versorgung von Kindern mit chronischen Magen-, Darm-, Pankreas- und Lebererkrankungen in Deutschland analysiert.

Methodik 319 Kliniken für Kinder- und Jugendmedizin sowie 50 kindergastroenterologische Praxen in Deutschland wurden eingeladen, an der anonymen Online-Umfrage über EFS Survey teilzunehmen. Es wurden die Struktur der Einrichtungen, Weiterbildungsbefugnisse, Kooperationen, Behandlungs- bzw. Betreuungsdaten und eine Einschätzung des Versorgungsbedarfs systematisch erfasst und deskriptiv ausgewertet.

Ergebnisse An der Umfrage haben 81 Kliniken und 10 Praxen teilgenommen. Fast zwei Drittel der Kliniken (n=52) erbringen ambulante kindergastroenterologische Leistungen. Meist bis zu 10 (25,4%) oder 20 Stunden/Woche (33,8%). Ein Viertel der Kliniken bietet keine Sprechstunden an. Der ambulante Versorgungsbedarf kann von zwei Dritteln der Institutionen nicht gedeckt werden. Die Hälfte aller Kliniken gab an, dass der stationäre kindergastroenterologische Versorgungsbedarf gedeckt werden kann. Ein Drittel kann diesen jedoch nicht abdecken und nur selten gibt es ungenutzte Kapazitäten. 35 Kliniken (43,2%) verfügen über eine Weiterbildungsbefugnis gemäß Landesärztekammer (n=33) und/oder sind Weiterbildungszentrum der Gesellschaft für pädiatrische Gastroenterologie und Ernährung (GPGE) (n=18).

Schlussfolgerung Es besteht sowohl ein ambulantes als auch stationäres Versorgungsdefizit in der Kinder- und Jugendgastroenterologie. Dieses resultiert unter anderem aus den ökonomischen Rahmenbedingungen und Personalmangel. Gut ausgebildete Fachärzt*innen mit Spezialisierung in Kinder- und Jugendgastroenterologie werden für eine flächendeckende qualifizierte Versorgung weiterhin benötigt. Zukünftige Studien sollten auch den kindergastroenterologischen Versorgungsbedarf aus Sicht anderer Gruppen einbeziehen, wie betroffener Patienten*innen, internistischer Gastroenterolog*innen und niedergelassener Kinder- und Jugendärzt*innen.

Compound heterozygous variants in OTULIN are associated with fulminant atypical late-onset ORAS

Autoinflammatory diseases are a heterogenous group of disorders defined by fever and systemic inflammation suggesting involvement of genes regulating innate immune responses. Patients with homozygous loss-of-function variants in the OTU-deubiquitinase OTULIN suffer from neonatal-onset OTULIN-related autoinflammatory syndrome (ORAS) characterized by fever, panniculitis, diarrhea, and arthritis. Here, we describe an atypical form of ORAS with distinct clinical manifestation of the disease caused by two new compound heterozygous variants (c.258G>A (p.M86I)/c.500G>C (p.W167S)) in the OTULIN gene in a 7-year-old affected by a life-threatening autoinflammatory episode with sterile abscess formation. On the molecular level, we find binding of OTULIN to linear ubiquitin to be compromised by both variants; however, protein stability and catalytic activity is most affected by OTULIN variant p.W167S. These molecular changes together lead to increased levels of linear ubiquitin linkages in patient-derived cells triggering the disease. Our data indicate that the spectrum of ORAS patients is more diverse than previously thought and, thus, supposedly asymptomatic individuals might also be affected. Based on our results, we propose to subdivide the ORAS into classical and atypical entities.

Isolated Crohn's Colitis: Is Localization Crucial? Characteristics of Pediatric Patients From the CEDATA-GPGE Registry

INTRODUCTION

Pediatric patients with inflammatory bowel disease (IBD) are classified into Crohn's disease (CD), ulcerative colitis (UC), and unclassifiable (IBD-U). However, data provide evidence that ileal CD (L1) is distinct from colonic CD (L2). The aim of this study was to investigate the clinical features of isolated Crohn's colitis in a pediatric population.

MATERIAL AND METHODS

Children who were prospectively included in the CEDATA-GPGE registry on diagnosis were compared according to the diagnosis of CD with L2 vs. L1 and ileocolonic (L3) involvement pattern as well as IBD-U and UC. The clinical significance of L2 was investigated with regard to extraintestinal manifestations, treatment, surgery, and disease activity.

RESULTS

Fifty-two patients with L2 CD at a median age of 13.4 years (±3.8 SD) were compared with 182 L1 (13.8 ± 2.9 SD), 782 with L3 (12.8 ± 3.3 SD), 653 with UC (12.7 ± 3.8 SD), and 111 patients with IBD-U (11.9 ± 4.7 SD). Bloody stools at diagnosis were more common in L2 (44%) than in L1 (19.7%) and L3 (28.8%), but not as common as in UC (66.5%) and IBD-U (61.3%). Fewer CD patients with L2 (10.2%) received exclusive enteral nutrition therapy (EEN) as induction than patients with L1 (34.3%) and L3 (33.3%). After induction therapy, 42.3% of patients with L2 received immunosuppressants and 21% biologicals during follow-up (L1 56.5/10.5%; L3 59/21%; CU 43.5/11.9%; IBD-U 26.1/12.6%). Extraintestinal manifestations were more frequent in L2 (23.1%) vs. L1 (18.7%), L3 (20.2%), CU (15.8%), and IBD-U (11.7%). The number of patients requiring surgery did not differ within the CD subgroups and was significantly lower in UC and IBD-U. Perianal fistula surgery was significantly more common in L2 (44%) than in L1 (4.8%) or L3 (21.7%). In addition, the frequency of surgery for perianal abscesses was also more frequent in L2 (55.6%) than in L1 (12.7%) or L3 (38.4%).

CONCLUSIONS

The consideration of pediatric Crohn's colitis as a distinct disease seems necessary as it is characterized by extraintestinal manifestations (EIMs) with mainly joint involvement and perianal fistulas or abscesses requiring surgery and biologic therapy. Thus, colonic Crohn's disease may have an influence on the therapeutic stratification and should be addressed in further studies.

Training in pediatric hepatology across Europe: a survey of the National Societies Network (2016-2019) of the European Society for Paediatric Gastroenterology, Hepatology and Nutrition

Background

The widely recognized burden of liver diseases makes training in pediatric hepatology (PH) imperative. The aim of this survey, which was part of a global survey on training in pediatric gastroenterology, hepatology and nutrition (PGHN) across Europe, was to assess the PH and liver transplantation (LT) infrastructure, staff and training programs in PGHN training centers.

Method

Standardized questionnaires were collected from training centers via the presidents/representatives of the National Societies Network of the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) from June 2016 to December 2019.

Results

A total of 100 PGHN training centers participated in the survey (14/100 were national referral centers in PH and/or LT). Dedicated PH clinics were available in 75%, but LT clinics in only 11%. Dedicated beds for PGHN inpatients were available in 47/95 (49%) centers. Full-time or part-time specialists for PH care were available in 31/45 (69%) and 11/36 (31%) centers, respectively. Liver biopsies (LB) were performed in 93% of centers by: a PGHN specialist (35%); an interventional radiologist (26%); a pediatric surgeon (4%); or a combination of them (35%). Dividing the annual number of LBs in the centers performing LBs by the number of trainees gave a median (range) of 10 (1-125) per trainee. Transient elastography was available in 60/92 (65%) of centers.

Conclusions

The survey highlighted the differences and shortcomings in PH training across Europe. ESPGHAN should take initiatives together with National Societies to ensure the acquisition of PH knowledge and skills according to the ESPGHAN curriculum.

An infographic is available for this article at: http://www.annalsgastro.gr/files/journals/1/earlyview/2022/Infographic-Hepatology-training-paper.pdf

Association of training standards in pediatric gastroenterology, hepatology and nutrition in European training centers with formal national recognition of the subspecialty: a survey of the ESPGHAN National Societies Network 2016-2019

Background

This survey evaluated the effects of the recognition of pediatric gastroenterology, hepatology and nutrition (PGHN) on European PGHN training centers.

Method

Standardized questionnaires were collected from training centers via the presidents/representatives of the National Societies Network of the European Society for Pediatric Gastroenterology, Hepatology and Nutrition, from June 2016 to December 2019.

Results

A total of 100 training centers from 19 countries participated in the survey: 55 from 12 countries where PGHN is formally recognized (Group 1) and 45 from 7 countries where it is not (Group 2). Training centers in Group 2 were less likely to have an integrated endoscopy suite, a written training curriculum and a training lead (P=0.059, P<0.001 and P=0.012, respectively). Trainees in Group 2 were less likely to be exposed to an adequate number of diagnostic endoscopies, while no differences were found in relation to liver biopsies. Half of the training centers in both Groups do not have dedicated beds for PGHN patients, while in 64% and 58%, respectively, trainees do not participate in on-call programs for PGHN emergencies. Research training is mandatory in 26% of the centers. The duration of training, as well as the assessment and accreditation policies, vary between countries.

Conclusions

This study has revealed significant discrepancies and gaps in infrastructure and training programs, training leadership, and assessment of training and certification across European training centers in PGHN. Strategies to support the recognition of PGHN and to standardize and improve training conditions should be developed and implemented.

An infographic is available for this article at: http://www.annalsgastro.gr/files/journals/1/earlyview/2022/Infographic_AG-6496.pdf

Training in pediatric neurogastroenterology and motility across Europe: a survey of the ESPGHAN National Societies Network 2016-2019

Background

Method

Results

Conclusions

Positive and negative selection shape the human naïve B cell repertoire

Although negative selection of developing B cells in the periphery is well described, yet poorly understood, evidence of naive B cell positive selection remains elusive. Using 2 humanized mouse models, we demonstrate that there was strong skewing of the expressed immunoglobulin repertoire upon transit into the peripheral naive B cell pool. This positive selection of expanded naive B cells in humanized mice resembled that observed in healthy human donors and was independent of autologous thymic tissue. In contrast, negative selection of autoreactive B cells required thymus-derived Tregs and MHC class II–restricted self-antigen presentation by B cells. Indeed, both defective MHC class II expression on B cells of patients with rare bare lymphocyte syndrome and prevention of self-antigen presentation via HLA-DM inhibition in humanized mice resulted in the production of autoreactive naive B cells. These latter observations suggest that Tregs repressed autoreactive naive B cells continuously produced by the bone marrow. Thus, a model emerged, in which both positive and negative selection shaped the human naive B cell repertoire and that each process was mediated by fundamentally different molecular and cellular mechanisms.

Increase in foreign body and harmful substance ingestion and associated complications in children: a retrospective study of 1199 cases from 2005 to 2017

Background

Children with a history of caustic or foreign body ingestion (FBI) seem to be presenting more frequently to emergency departments. This study aims to elucidate the clinical presentation, diagnostic procedures, and complications associated with the ingestion of different object categories over a 13-year time period.

Methods

A structured retrospective data analysis of patients who presented between January 2005 and December 2017 to the University Medical Centre Ulm was performed. Patients up to 17 years of age with food impaction or foreign body or harmful substance ingestion were included by selection of the corresponding International Statistical Classification of Diseases and Related Health Problems (ICD10-GM) codes. Descriptive statistics, parametric or non-parametric tests, and linear regression analysis were performed.

Result

In total, 1199 patients were analysed; the mean age was 3.3 years (SD 3.12; range 7 days to 16 years), the male to female ratio was 1.15:1, and 194 (16.2%) were hospitalized. The number of patients seen annually increased from 66 in 2005 to 119 in 2017, with a rise in percentage of all emergency patients from 0.82% in 2010 to 1.34% in 2017. The majority of patients (n = 619) had no symptoms, and 244 out of 580 symptomatic patients complained of retching or vomiting. Most frequently, ingested objects were coins (18.8%). Radiopaque objects accounted for 47.6%, and sharp objects accounted for 10.5% of the ingested foreign bodies, both of which were significantly more often ingested by girls (p < 0.001 for both). Button battery ingestion was recorded for 63 patients with a significant annual increase (R2 = 0.57; β = 0.753; p = 0.003). The annual rate of complications also increased significantly (R2 = 0.42; β = 0.647; p = 0.017).

Conclusion

We found an alarming increase in the number of children who presented to our emergency department with FBI and associated complications. A standardized diagnostic and therapeutic approach may reduce and prevent serious complications. Further preventive measures within the home environment are needed to stop this trend.

[Crohn's Disease Exclusion Diet - an alternative to exlusive enteral nutritional therapy in children and adolescents with Crohn's disease? Statement of the GPGE working groups CEDATA and Nutrition/Nutrition Medicine]

Epidemiological an clinical observations as well as results from animal studies indicate that nutrition can play a role in the development of inflammatory bowel disease (IBD). Exclusive enteral nutrition therapy represents an example for modulating inflammatory responses solely through diet modification. Therefore, caretakers, patients, families, doctors and nutritionists seek for more dietary options to control IBD. These options include partial enteral nutrition therapy as for example the socalled Crohn's disease exclusion diet. The following statement summarizes existing data and provides recommendations for the current management of enteral nutrition therapy in pediatric Crohn's disease.

Acute Infectious Gastroenteritis in Infancy and Childhood

BACKGROUND

Despite the introduction of vaccination against rotavirus, and even though it can often be treated on an outpatient basis, acute infectious gastroenteritis is nevertheless the second most common non-traumatic cause of emergency hospitaliza - tion in children aged 1 to 5 years, accounting for approximately 9% of cases (39 410 cases in 2017). The most common path - ogens are viruses (47% rotavirus, 29% norovirus, and 14% adenovirus).

METHODS

This review is based on publications retrieved by a selective search in PubMed employing the terms "acute gastro - enteritis children" AND "dehydration" OR "rehydration" OR "prevention," and by manual searching (based, for example, on reference lists and expert knowledge), with subsequent evaluation including consideration of the relevant guidelines.

RESULTS

The degree of dehydration can be judged from weight loss and other clinical findings. In 17 randomized controlled trials conducted on a total of 1811 children with mild or moderate dehydration, oral rehydration with oral rehydration solution was just as effective as intravenous rehydration with respect to weight gain, duration of diarrhea, and fluid administration, and was associated with shorter hospital stays (weighted mean difference, -1.2 days; 95% confidence interval [-2.38; -0.02]). Oral rehydration therapy failed in 4% of patients [1; 7]. In children who are vomiting or who refuse oral rehydration solution, continuous nasogastric application is just as effective as intravenous rehydration and is the treatment of first choice.

CONCLUSION

In Germany, children with mild or moderate dehydration are often hospitalized for intravenous rehydration therapy, despite the good evidence supporting ambulatory oral rehydration. Obstacles to intersectoral care, the nursing shortage, and inadequate reimbursement must all be overcome in order to reduce unnecessary hospitalizations and thereby lessen the risk of nosocomial infection.

[The gut: center of immunity : Rare inflammatory bowel diseases caused by immunodeficiencies]

The gut is the largest immune organ of the human body with an enormous mucosal interface. By acting as a physical barrier and by hosting many of the body's immune cells and tissues, the gut is the first line of defense against potentially harmful substances. Therefore, diseases leading to impaired immune response or disruption of the epithelial barrier result in autoimmune, infectious, or inflammatory bowel disease, frequently associated with diarrhea, malabsorption, melena, and growth failure. The differential diagnosis represents an interdisciplinary challenge in this group of rare diseases. The diseases are characterized by clinical, immunological, and histopathological features caused by mutations in single genes. In the following, we will focus on histological findings within the various entities of immunodeficiencies.

Somatic mosaicism and common genetic variation contribute to the risk of very-early-onset inflammatory bowel disease

Very-early-onset inflammatory bowel disease (VEO-IBD) is a heterogeneous phenotype associated with a spectrum of rare Mendelian disorders. Here, we perform whole-exome-sequencing and genome-wide genotyping in 145 patients (median age-at-diagnosis of 3.5 years), in whom no Mendelian disorders were clinically suspected. In five patients we detect a primary immunodeficiency or enteropathy, with clinical consequences (XIAP, CYBA, SH2D1A, PCSK1). We also present a case study of a VEO-IBD patient with a mosaic de novo, pathogenic allele in CYBB. The mutation is present in ~70% of phagocytes and sufficient to result in defective bacterial handling but not life-threatening infections. Finally, we show that VEO-IBD patients have, on average, higher IBD polygenic risk scores than population controls (99 patients and 18,780 controls; P < 4 × 10-10), and replicate this finding in an independent cohort of VEO-IBD cases and controls (117 patients and 2,603 controls; P < 5 × 10-10). This discovery indicates that a polygenic component operates in VEO-IBD pathogenesis.

Roles of Lactose and Fructose Malabsorption and Dietary Outcomes in Children Presenting with Chronic Abdominal Pain

Intolerance to lactose or fructose is frequently diagnosed in children with chronic abdominal pain (CAP). However, the causal relationship remains a matter of discussion. A cohort of 253 patients, aged 7–12 years, presenting with unexplained CAP received standardized diagnostics. Additional diagnostic tests were performed based on their medical history and physical and laboratory investigations. Fructose and lactose hydrogen breath tests (H₂BT) as well as empiric diagnostic elimination diets were performed in 135 patients reporting abdominal pain related to the consumption of lactose or fructose to evaluate carbohydrate intolerance as a potential cause of CAP. Carbohydrate malabsorption by H2BT was found in 55 (41%) out of 135 patients. An abnormal increase in H2BT was revealed in 30% (35/118) of patients after fructose consumption and in 18% (20/114) of patients after lactose administration. Forty-six percent (25/54) reported pain relief during a diagnostic elimination diet. In total, 17 patients had lactose malabsorption, 29 fructose malabsorption, and nine combined carbohydrate malabsorption. Carbohydrate intolerance as a cause of CAP was diagnosed at follow-up in only 18% (10/55) of patients with malabsorption after the elimination of the respective carbohydrate. Thus, carbohydrate malabsorption appears to be an incidental finding in children with functional abdominal pain disorders, rather than its cause. Therefore, testing of carbohydrate intolerance should only be considered in children with a strong clinical suspicion and with the goal to prevent long-term unnecessary dietary restrictions in children suffering from CAP.

Dataset of clinical, immunohistopathological and laboratory features of patients with MHC II deficiency suffering from enteropathy

Major histocompatibility complex class II (MHC II) is essential for adaptive immune response. We recently reported on disturbed adaptive mucosal immunity due to MHC II deficiency and prolonged enteropathy. Here, we share medical history, flow cytometric analysis of blood lymphocytes, immunohistopathology, and fecal analysis of seven genetically confirmed patients with MHC II deficiency suffering from enteropathy. Data on flow cytometric analysis of HLA-DR expression on monocytes and B cells before hematopoietic stem cell transplantation (HSCT) and after in-vitro stimulation is shown. The course of immune reconstitution after HSCT of MHC II deficient patients in comparison to severe combined immunodeficiency (SCID) patients is described. In addition, immunohistopathology illustrating CD4 and CD8 T cell infiltration, absence of B lymphocytes and plasma cells, and disturbed immunoglobulin expression in the gut as well as absent HLA-DR expression in the liver is shown. Furthermore, data from fecal analysis such as stool fat, nitrogen, and water fraction as well as faecal markers such as alpha-1-antitrypsin, pancreas specific elastase 1, eosinophilic protein X (EPX), and beta defensin 2 are presented. Altogether this data demonstrates the complex phenotype of MHC II deficiency. The data can be valuable for researchers interested in mucosal immunity. For further interpretation of the data presented in this article, please see the research article “Persisting enteropathy and disturbed adaptive mucosal immunity due to MHC class II deficiency” (Posovszky et al., 2019).

Carbon dioxide versus room air for colonoscopy in deeply sedated pediatric patients: a randomized controlled trial

Background and study aims  Use of carbon dioxide (CO ₂ ) instead of room air (RA) during colonoscopy in adults revealed significantly less flatulence and abdominal pain in several studies. The objectives of this study were to investigate the effects of CO ₂ usage on post-interventional pain, abdominal discomfort, abdominal girth, pCO ₂ levels, and narcotic requirement in deeply sedated pediatric patients. Patients and methods  A total of 97 children and adolescents aged 4 years to 17 years undergoing colonoscopy were randomized to RA or CO ₂ in a prospective, randomized, controlled trial. Age-appropriate pain scales assessed abdominal pain as primary outcome. In addition, abdominal girth, abdominal bloating, transcutaneous pCO ₂ , narcotic requirement to achieve deeply sedation, and post-procedural analgesic demand was analyzed in 73 patients. Results  Overall, significantly fewer patients reported bloating in the CO ₂ group ( P  = 0.0012). However, we observed only a trend to lower post-interventional pain ( P  = 0.15) and a lower pain score. There was no significant difference in transcutaneous pCO ₂ level and no adverse events occurred. Although there was no difference in the dosage of propofol and midazolam, we observed a significant increased necessity for use of synthetic opioids in the RA group to achieve optimal examination conditions ( P  = 0.023). Conclusions  The benefits using CO ₂ in colonoscopy of deeply sedated children predominate. In particular, CO ₂ insufflation may allow a less painful post-interventional time and it significantly reduces abdominal bloating. Moreover, with CO ₂ , significantly less additional opioids were used. Thus, CO ₂ insufflation can be considered as safe in deeply sedated patients as there was no relevant pulmonary CO ₂ retention observed. (DRKS00013914).

Preserved in vitro immunoreactivity in children receiving long-term immunosuppressive therapy due to inflammatory bowel disease or autoimmune hepatitis

Background

Children with inflammatory bowel disease (IBD) or autoimmune hepatitis (AIH) are at risk for severe infections. This is partially a result of their chronic disease condition but, moreover, a side effect of their immunosuppressive therapy. Currently, vaccinations with live vaccines are regarded as contraindicated under immunosuppressive therapy, mainly because of concerns about side effects and a lack of data showing an adequate immune reaction. As there is no systematic study on the individual immunoreactivity under immunosuppressive therapy in this patient group, we analyzed the lymphocyte subgroups and immunoreactivity of lymphocytes in children with IBD or AIH with and without immunosuppressive therapy in vitro.

Methods

We collected whole blood samples from 17 children with IBD or AIH on high-level immunosuppression (IS) (group 1) and 8 on low-level IS (group 2) in comparison with 6 patients without systemic IS (group 3). After Ficoll separation of peripheral mononuclear cells, the samples were analyzed by flow cytometry to determine the lymphocyte subgroups. Furthermore, we stimulated the isolated lymphocytes with phytohemagglutinin (PHA), tetanus antigen, and adenovirus antigen and measured their proliferation by incorporation of H₃-thymidine detected in a beta counter.

The statistical evaluation was performed by Kruskal-Wallis test and Mann-Whitney U test using a bilateral level of significance of α = 5%.

Results

Patients with low- or high-level IS showed no significant difference in the number of lymphocytes or T cells.

Interestingly, IS did not influence the lymphocyte proliferation assay significantly regarding median reaction to PHA, tetanus antigen, or adenovirus antigen between the three groups. However, comparing all immunosuppressed patients to the patients without IS, there was a significant difference towards stimulation with tetanus antigen.

Conclusions

Contrary to expectations of a strong influence of IS therapy on the immunoreactivity, this study showed only minor differences between the groups with high-level, low-level, and no IS. Particularly, the in vitro reactivity to adenovirus antigen was nearly the same in all three groups. We assume that—provided a normal distribution and count of lymphocyte subgroups—patients with moderate immunosuppression might be capable of raising an effective immune response to inactivated and live vaccines.

Electronic supplementary material

The online version of this article (10.1186/s40348-018-0079-0) contains supplementary material, which is available to authorized users.

MYO5B, STX3, and STXBP2 mutations reveal a common disease mechanism that unifies a subset of congenital diarrheal disorders: A mutation update

Microvillus inclusion disease (MVID) is a rare but fatal autosomal recessive congenital diarrheal disorder caused by MYO5B mutations. In 2013, we launched an open‐access registry for MVID patients and their MYO5B mutations (www.mvid-central.org). Since then, additional unique MYO5B mutations have been identified in MVID patients, but also in non‐MVID patients. Animal models have been generated that formally prove the causality between MYO5B and MVID. Importantly, mutations in two other genes, STXBP2 and STX3, have since been associated with variants of MVID, shedding new light on the pathogenesis of this congenital diarrheal disorder. Here, we review these additional genes and their mutations. Furthermore, we discuss recent data from cell studies that indicate that the three genes are functionally linked and, therefore, may constitute a common disease mechanism that unifies a subset of phenotypically linked congenital diarrheal disorders. We present new data based on patient material to support this. To congregate existing and future information on MVID geno‐/phenotypes, we have updated and expanded the MVID registry to include all currently known MVID‐associated gene mutations, their demonstrated or predicted functional consequences, and associated clinical information.

Vedolizumab in Paediatric Inflammatory Bowel Disease: A Retrospective Multi-Centre Experience From the Paediatric IBD Porto Group of ESPGHAN

BACKGROUND

Vedolizumab, an anti-integrin antibody, has proven to be effective in adults with inflammatory bowel disease [IBD], but the data in paediatrics are limited. We describe the short-term effectiveness and safety of vedolizumab in a European multi-centre paediatric IBD cohort.

METHOD

Retrospective review of children [aged 2-18 years] treated with vedolizumab from 19 centres affiliated with the Paediatric IBD Porto group of ESPGHAN. Primary outcome was Week 14 corticosteroid-free remission [CFR].

RESULTS

In all, 64 children were included (32 [50%] male, mean age 14.5 ± 2.8 years, with a median follow-up 24 weeks [interquartile range 14-38; range 6-116]); 41 [64%] cases of ulcerative colitis/inflammatory bowel disease unclassified [UC/IBD-U] and 23 [36%] Crohn's disease [CD]. All were previously treated with anti-tumour necrosis factor [TNF] [28% primary failure, 53% secondary failure]. Week 14 CFR was 37% in UC, and 14% in CD [P = 0.06]. CFR by last follow-up was 39% in UC and 24% in CD [p = 0.24]. Ten [17%] children required surgery, six of whom had colectomy for UC. Concomitant immunomodulatory drugs did not affect remission rate [42% vs 35%; p = 0.35 at Week 22]. There were three minor drug-related adverse events. Only 3 of 16 children who underwent endoscopic evaluation had mucosal healing after treatment (19%).

CONCLUSIONS

Vedolizumab was safe and effective in this cohort of paediatric refractory IBD. These data support previous findings of slow induction rate of vedolizumab in CD and a trend to be less effective compared with patients with UC.

Disrupted apical exocytosis of cargo vesicles causes enteropathy in FHL5 patients with Munc18-2 mutations

Familial hemophagocytic lymphohistiocytosis 5 (FHL5) is an autosomal recessive disease caused by mutations in STXBP2, coding for Munc18-2, which is required for SNARE-mediated membrane fusion. FHL5 causes hematologic and gastrointestinal symptoms characterized by chronic enteropathy that is reminiscent of microvillus inclusion disease (MVID). However, the molecular pathophysiology of FHL5-associated diarrhea is poorly understood. Five FHL5 patients, including four previously unreported patients, were studied. Morphology of duodenal sections was analyzed by electron and fluorescence microscopy. Small intestinal enterocytes and organoid-derived monolayers displayed the subcellular characteristics of MVID. For the analyses of Munc18-2-dependent SNARE-protein interactions, a Munc18-2 CaCo2-KO model cell line was generated by applying CRISPR/Cas9 technology. Munc18-2 is required for Slp4a/Stx3 interaction in fusion of cargo vesicles with the apical plasma membrane. Cargo trafficking was investigated in patient biopsies, patient-derived organoids, and the genome-edited model cell line. Loss of Munc18-2 selectively disrupts trafficking of certain apical brush-border proteins (NHE3 and GLUT5), while transport of DPPIV remained unaffected. Here, we describe the molecular mechanism how the loss of function of Munc18-2 leads to cargo-selective mislocalization of brush-border components and a subapical accumulation of cargo vesicles, as it is known from the loss of polarity phenotype in MVID.

Development and Anatomy of the Enteroendocrine System in Humans

The gastrointestinal (GI) tract exhibits an enormous surface area that consists mostly of absorptive enterocytes. Enteroendocrine cells (EECs) are found scattered along the GI tract between absorptive enterocytes and other secretory cells, and comprise around 1% of the epithelial cell population. Interestingly, they develop from the same crypt stem cell as the other absorptive or secretory cells of the gut. EECs differentiate along the crypt villus axis and are renewed every 4-6 days, and hence possess a high plasticity. They constitute the largest endocrine system in the human body by secreting multiple peptide hormones to control, for example, postprandial digestion, insulin homeostasis, food intake, and gut motility. For this purpose, most EECs exhibit luminal sensors that detect the GI tract content. Thereafter, they may act either in a classical endocrine fashion, or by paracrine effects on nearby neural and immune cells. This creates a pivotal role for EECs to influence the GI immune system and the enteric nervous system. In this chapter, the anatomical characteristics, development, differentiation and maturation of EECs are described, and their important biological potential illustrated as part of the gut interacting sensory system.

The role of enterocyte defects in the pathogenesis of congenital diarrheal disorders

Congenital diarrheal disorders are rare, often fatal, diseases that are difficult to diagnose (often requiring biopsies) and that manifest in the first few weeks of life as chronic diarrhea and the malabsorption of nutrients. The etiology of congenital diarrheal disorders is diverse, but several are associated with defects in the predominant intestinal epithelial cell type, enterocytes. These particular congenital diarrheal disorders (CDD^ENT) include microvillus inclusion disease and congenital tufting enteropathy, and can feature in other diseases, such as hemophagocytic lymphohistiocytosis type 5 and trichohepatoenteric syndrome. Treatment options for most of these disorders are limited and an improved understanding of their molecular bases could help to drive the development of better therapies. Recently, mutations in genes that are involved in normal intestinal epithelial physiology have been associated with different CDD^ENT. Here, we review recent progress in understanding the cellular mechanisms of CDD^ENT. We highlight the potential of animal models and patient-specific stem-cell-based organoid cultures, as well as patient registries, to integrate basic and clinical research, with the aim of clarifying the pathogenesis of CDD^ENT and expediting the discovery of novel therapeutic strategies.

Summary: Overview of the recent progress in our understanding of congenital diarrheal disorders, and the available models to study these diseases.

Bowel preparation in pediatric colonoscopy: results of an open observational study

BACKGROUND AND STUDY AIMS

The goal of this study was to analyze the bowel cleansing methods currently used for pediatric colonoscopy in terms of effectiveness, tolerance and safety.

PATIENTS AND METHODS

Data from 768 colonoscopies reported by 28 centers were registered in an online database for further analysis. Binary logistic regression was used to determine how preparation methods affected the cleaning effect (Aronchick score) and the rate of adverse events (Aes) and complications.

RESULTS

The most frequently reported cleansing agents were sodium picosulphate (54.2 %) and polyethylene-glycol (41.3 %) in various combinations. The cleaning effect was good to excellent in 72.6 % of patients. AEs during the preparation period occurred in 21.5 % of patients. Complications during endoscopy were reported in 12.1 % and were mostly mild. The different agents had no influence on the cleaning effect. In contrast the risk of AEs during preparation was significantly increased when polyethylene-glycol was used (odds ratio (OR) 2.112, P = 0.002) but reduced with the use of sodium picosulphate (OR 0.380, P < 0.001). In particular, the risk of needing a nasogastric tube to complete clean-out was about 10-fold higher when polyethylene-glycol was used.

CONCLUSIONS

A large variety of regimens are used for bowel preparation in children. We found a good overall cleaning result independent of the agents used. Cleansing agents, on the other hand, had a significant influence on tolerance and safety.

Regulation of appetite, satiation, and body weight by enteroendocrine cells. Part 1: characteristics of enteroendocrine cells and their capability of weight regulation

The gastrointestinal tract is the gateway for food in our body. Food ingestion and the ensuing digestive processes depend on the composition and amount of ingested nutrients. This complex process of nutrient digestion and absorption is effectively regulated by the enteroendocrine system. Enteroendocrine cells (EECs) reside scattered throughout the intestinal epithelium. They express nutrient receptors that face the lumen and secrete peptide hormones in response to food. Besides regulating digestion, gastrointestinal endocrine cells are involved in the regulation of appetite and satiety. The first part of this review describes the anatomical and biological characteristics of EECs and discusses the capability of their hormones to influence appetite, satiety, and body weight. In the second part, we then discuss the therapeutic potential of EECs in the treatment of obesity.

Regulation of appetite, satiation, and body weight by enteroendocrine cells. Part 2: therapeutic potential of enteroendocrine cells in the treatment of obesity

Obesity is an epidemic and medical issue. Investigating the pathways regulating appetite, food intake, and body weight is crucial to find strategies for the prevention and treatment of obesity. In the context of therapeutic strategies, we focus here on the potential of enteroendocrine cells (EECs) and their secreted hormones in the regulation of body weight. We review the role of the enteroendocrine system during weight loss after lifestyle intervention or after bariatric surgery. We discuss the therapeutic potential of EECs and their hormones as targets for new treatment strategies. In fact, targeting nutrient receptors of EECs with a nutritional approach, pharmaceutical agents or prebiotics delivered to the lumen may provide a promising new approach.

Head Injury in Children: Has a Change in Circumstances Caused an Increase in Treatment Numbers?

The number of hospitalizations for head injuries in children is rising. The exact causes remain unclear. We analyzed data of children aged between 0 and 18 years who sustained a head injury between 2010 and 2011. The analysis focused on data related to demographics, trauma mechanism, clinical course, results of imaging scans, concomitant injuries, and outcome. A total of 794 inpatient cases of head injury were treated. The leading mechanism of injury was a fall (at home) primarily at the age of 1 to 4 years (46.5%), with the majority of the children sustaining a mild brain injury (764, 96.2%). Neurosurgery was performed in 21 (2.64%) cases; average hospital stay was 2.9 days (range: 0-68 days). This study is not able to confirm that children are increasingly being brought to the hospital by their parents because of new trauma mechanisms or parents' uncertainty, nor can we confirm that the number of nonaccidental injuries is rising.

Stop the pain: study protocol for a randomized-controlled trial

BACKGROUND

Functional abdominal pain (FAP) is not only a highly prevalent disease but also poses a considerable burden on children and their families. Untreated, FAP is highly persistent until adulthood, also leading to an increased risk of psychiatric disorders. Intervention studies underscore the efficacy of cognitive behavioral treatment approaches but are limited in terms of sample size, long-term follow-up data, controls and inclusion of psychosocial outcome data.

METHODS/DESIGN

In a multicenter randomized controlled trial, 112 children aged 7 to 12 years who fulfill the Rome III criteria for FAP will be allocated to an established cognitive behavioral training program for children with FAP (n = 56) or to an active control group (focusing on age-appropriate information delivery; n = 56). Randomization occurs centrally, blockwise and is stratified by center. This study is performed in five pediatric gastroenterology outpatient departments. Observer-blind assessments of outcome variables take place four times: pre-, post-, 3- and 12-months post-treatment. Primary outcome is the course of pain intensity and frequency. Secondary endpoints are health-related quality of life, pain-related coping and cognitions, as well as self-efficacy.

DISCUSSION

This confirmatory randomized controlled clinical trial evaluates the efficacy of a cognitive behavioral intervention for children with FAP. By applying an active control group, time and attention processes can be controlled, and long-term follow-up data over the course of one year can be explored.

TRIAL REGISTRATION

DRKS00005038 (date: 25 July 2013); NCT02030392 (date: 7 January 2014).

Health-related quality of life in children with abdominal pain due to functional or organic gastrointestinal disorders

OBJECTIVE

Comparing health-related quality of life (HRQOL) in children suffering from functional and organic gastrointestinal disorders and to identify predictors for HRQOL.

METHODS

Children with functional (n = 70) and organic (n = 100) gastrointestinal disorders, aged 8-18 years and referred to a pediatric gastroenterologist, completed questionnaires assessing pain severity, coping, and HRQOL.

RESULTS

The sample reported low HRQOL scores, even significantly lower compared with reference values of chronically ill children, derived from normative data of KINDL-R, a generic QOL questionnaire. HRQOL was not significantly associated with age, gender, duration of pain, and diagnosis (functional gastrointestinal disorder vs. organic gastrointestinal disorder). Pain severity and catastrophizing were significantly associated with HRQOL, with catastrophizing fully mediating the relationship between pain and HRQOL.

CONCLUSION

The emotional burden associated with chronic abdominal pain-regardless of its cause-is enormous. Interventions should target the children's coping strategies, as catastrophizing seems to be the causal link between pain and HRQOL.

Persistent defective membrane trafficking in epithelial cells of patients with familial hemophagocytic lymphohistiocytosis type 5 due to STXBP2/MUNC18-2 mutations

BACKGROUND

Familial hemophagocytic lymphohistiocytosis (FHL) is a rare primary immune disorder defined by mutations in the syntaxin binding protein 2 (STXBP2) alias MUNC18-2. Despite defective immunity and a hyper-inflammatory state, clinical findings such as neurological, gastrointestinal, and bleeding disorders are present in a significant number of patients and suggest an impaired expression and function of STXBP2 in cells other than cytotoxic lymphocytes.

PROCEDURE

We investigated four patients with FHL5 suffering from severe enteropathy and one of whom also had renal tubular dysfunction despite successful hematopoietic stem cell transplantation (HSCT). Gastrointestinal and renal biopsy specimens were analyzed by immunohistochemistry and electron microscopy.

RESULTS

Histopathology revealed an intracytoplasmatic accumulation of PAS-positive granules and an enlarged intracytoplasmatic CD10-positive band along the apical pole of enterocytes. Electron microscopy revealed short microvilli and granules filled with electro lucent material. In addition, we described mildly dilated renal tubules and electron micrographs displayed a higher number of cytoplasmic inclusions, electrodense lysosomal and electrolucent endosomal vesicles.

CONCLUSION

Mutations in STXBP2 do not only affect cytotoxic T lymphocytes but also cause changes in the intestinal and renal epithelium resulting in severe, osmotic diarrhea and renal proximal tubular dysfunction. These defects persist after successful treatment of hemophagocytic lymphohistocytosis by HSCT. Clinical manifestations in FHL5 patients despite successful HSCT may therefore be related to defective membrane trafficking in the gut and kidney.

Age-of-onset-dependent influence of NOD2 gene variants on disease behaviour and treatment in Crohn's disease

Background

Influence of genetic variants in the NOD2 gene may play a more important role in disease activity, behaviour and treatment of pediatric- than adult-onset Crohn’s disease (CD).

Methods

85 pediatric- and 117 adult-onset CD patients were tested for the three main NOD2 CD-associated variants (p.R702W, p.G908R and p.10007fs) and clinical data of at least two years of follow-up were compared regarding disease behaviour and activity, response to therapy and bone mineral density (BMD).

Results

Chronic active and moderate to severe course of CD is associated in patients with pediatric-onset (p=0.0001) and NOD2 variant alleles (p=0.0001). In pediatric-onset CD the average PCDAI-Score was significantly higher in patients carrying NOD2 variants (p=0.0008). In addition, underweight during course of the disease (p=0.012) was associated with NOD2 variants. Interestingly, osteoporosis was found more frequently in patients carrying NOD2 variant alleles (p=0.033), especially in pediatric-onset CD patients with homozygous NOD2 variants (p=0.037). Accordingly, low BMD in pediatric-onset CD is associated with a higher PCDAI (p=0.0092), chronic active disease (p=0.0148), underweight at diagnosis (p=0.0271) and during follow-up (p=0.0109). Furthermore, pediatric-onset CD patients with NOD2 variants are more frequently steroid-dependent or refractory (p=0.048) and need long-term immunosuppressive therapy (p=0.0213).

Conclusions

These data suggests that the presence of any of the main NOD2 variants in CD is associated with osteoporosis and an age of onset dependent influence towards underweight, higher disease activity and a more intensive immunosuppressive therapy. This observation supports the idea for an early intensive treatment strategy in children and adolescent CD patients with NOD2 gene variants.

Loss of enteroendocrine cells in autoimmune-polyendocrine-candidiasis-ectodermal-dystrophy (APECED) syndrome with gastrointestinal dysfunction

BACKGROUND

Enteroendocrine (EE) cells are necessary for the regulation of gastrointestinal function. The lack of intestinal enteroendocrine cells in enteroendocrine cell dysgenesis causes severe malabsorptive diarrhea. Autoimmune-polyendocrinopathy-candidiasis-ectodermal-dystrophy (APECED) is often accompanied by gastrointestinal (GI) symptoms.

AIMS

We hypothesized that an autoimmune attack against the cells of the GI-associated diffuse endocrine system may be a specific feature of GI dysfunction in APECED disorders.

METHODS

Biopsies were obtained during routine diagnostic endoscopy from 35 pediatric patients with gastrointestinal symptoms as well as from five healthy controls; biopsies were immunostained for chromogranin A and serotonin. Four patients were classified as APECED syndrome on molecular and clinical grounds.

RESULTS

Immunohistological analysis of biopsies along the GI tract (stomach, duodenum, colon) immunostained with chromogranin A and serotonin revealed a widespread reduction or complete loss of EE cells in all four patients with APECED syndrome suffering from severe diarrhea, vomiting, malabsorption, or constipation. In contrast, EE cells were present in pediatric patients with similar gastrointestinal symptoms caused by inflammatory bowel disease, celiac disease, lymphocytic colitis, and autoimmune disorders without endocrinopathy or graft vs. host disease of the gut.

CONCLUSIONS

The reduction of EE cells is a specific and important early event in the pathogenesis of APECED with GI dysfunction. We propose a diagnostic algorithm integrating clinics, genetics and immunohistology.