Impact of genetic and non-genetic factors on phenotypic diversity in NBAS-associated disease.

Biallelic pathogenic variants in neuroblastoma-amplified sequence (NBAS) cause a pleiotropic multisystem disorder. Three clinical subgroups have been defined correlating with the localisation of pathogenic variants in the NBAS gene: variants affecting the C-terminal region of NBAS result in SOPH syndrome (short stature, optic atrophy, Pelger-Huët anomaly), variants affecting the Sec 39 domain are associated with infantile liver failure syndrome type 2 (ILFS2) and variants affecting the ß-propeller domain give rise to a combined phenotype. However, there is still unexplained phenotypic diversity across the three subgroups, challenging the current concept of genotype-phenotype correlations in NBAS-associated disease. Therefore, besides examining the genetic influence, we aim to elucidate the potential impact of pre-symptomatic diagnosis, emergency management and other modifying variables on the clinical phenotype. We investigated genotype-phenotype correlations in individuals sharing the same genotypes (n = 30 individuals), and in those sharing the same missense variants with a loss-of-function variant in trans (n = 38 individuals). Effects of a pre-symptomatic diagnosis and emergency management on the severity of acute liver failure (ALF) episodes also were analysed, comparing liver function tests (ALAT, ASAT, INR) and mortality. A strong genotype-phenotype correlation was demonstrated in individuals sharing the same genotype; this was especially true for the ILFS2 subgroup. Genotype-phenotype correlation in patients sharing only one missense variant was still high, though at a lower level. Pre-symptomatic diagnosis in combination with an emergency management protocol leads to a trend of reduced severity of ALF. High genetic impact on clinical phenotype in NBAS-associated disease facilitates monitoring and management of affected patients sharing the same genotype. Pre-symptomatic diagnosis and an emergency management protocol do not prevent ALF but may reduce its clinical severity.

Growth development of children and adolescents with inflammatory bowel disease in the period 2000-2014 based on data of the Saxon pediatric IBD registry: a population-based study.

BACKGROUND: The incidence of inflammatory bowel disease (IBD) in children is on the increase worldwide. Growth disorders are common in pediatric patients with inflammatory bowel disease. The aim of this paper is to investigate anthropometric indicators, including height and weight in children with inflammatory bowel disease in Saxony, one of the German federal states, and to evaluate growth trends in patients by comparing their height and weight with that of healthy children in Germany. METHODS: In Saxony, all children and adolescents with IBD were registered in the Saxon Pediatric IBD Registry from 2000 to 2014. The data used are therefore based on a total area-wide survey over 15 years. For this study, 421 datasets of children and adolescents aged 0-14 years with Crohn's disease (CD) (n = 291) or ulcerative colitis (UC) (n = 130) were analyzed. Z-score and percentile calculations were used to compare differences between IBD patients and the general population. RESULTS: The children with CD or UC (both sexes) had a significant lower weight at diagnosis (the mean weight z-score had negative values) versus the general population. The weight values lay mostly below P50 (the 50th percentile, median), more precisely, mostly between P10 and P50 of the body weight child growth curve for corresponding sexes (KiGGS 2003-2006). The height values of both sexes at diagnosis lay also mostly below P50 (the 50th percentile, median) of the child body growth curve for corresponding sexes (KiGGS 2003-2006), i.e. the mean height z-score was negative. But only the children with CD had a significant lower height, more precisely, mostly between P25 and P50 versus the general population (KIGGS). For children with UC the difference was not significant. CONCLUSION: In pediatric patients with IBD the possibility of growth disturbance, mainly in the form of weight retardation, is very probable.

Metamizole-induced agranulocytosis (MIA): a mini review.

Metamizole is an analgesic, antipyretic, and spasmolytic drug in Germany only approved for the treatment of severe pain or high fever that does not respond to other measures. In recent years, an increased use has been described among both adults and children, often against the approved indication. The most important side effect of metamizole is the development of agranulocytosis (neutrophil count < 500/µL). Incidence of metamizole-induced agranulocytosis (MIA) ranges depending on the study from 0.96 cases per million per year to 1:1602 per patient and metamizole prescription. The risk of agranulocytosis in children remains unclear, but is probably lower than in adults. Female gender and older age are associated with higher incidence, reflecting prescription distribution. MIA is dose-independent and risk seems to increase with duration of intake. In patients with past exposure, re-exposure may lead to rapid onset. MIA is believed to be induced either through immunologic or toxic mechanisms. MIA presents with fever, sore throat, fatigue, and mucosal inflammation, up to ulceration. Even in the case of suspected MIA, treatment with metamizole should be immediately paused and an examination of the blood cell count is required. In case of local or systemic infections, empirical therapy with broad-spectrum antibiotics should be administered. G-CSF therapy should be limited to patients with poor prognostic factors. The patient should be monitored closely until the neutrophil count returns to normal. Re-exposure to metamizole must be avoided.

Clinical course of new-onset Crohn's disease in children and adolescents in dependency of age, initial location, initial severity level and therapy over the period 2000-2014 based on the Saxon Pediatric IBD-Registry in Germany.

OBJECTIVE: In Saxony, the incidence of Crohn's disease (CD) in children and adolescents increased significantly from 3.3 per 100,000 person-years in 2000 to 5.1 in 2014. The aim of this study was to describe the initial characteristics and the clinical course of CD in children and adolescents and to identify drug treatment options associated with an advantage for a mild course or remission. METHODS: Clinical data were collected from patients who suffered from inflammatory bowel disease (IBD) and were recruited in the Saxon Pediatric IBD-Registry. All children newly diagnosed with CD in this registry in Saxony between 2000 and 2014 were included in this registry study. Characteristics such as age, disease location and extra-intestinal manifestations at diagnosis were accessed. The severity level of the disease at diagnosis as well as at follow-up were analysed by PCDAI index. Patients were divided into 3 groups according to length of follow-up: 1-3 years, 4-6 years and 7-9 years after diagnosis. A logistic regression model was conducted to examine which baseline parameters are associated with disease progression. RESULTS: There were 338 children and adolescents with CD included in this registry study. At diagnosis, the median age of patients was 12.0 (0.7-14.9), 61.5% (n = 208) of the patients were male. The most common disease location observed in pediatric CD patients was the L3 (55%, n = 176). Patients aged 10-14 years were significantly more likely to present an L2 than patients aged 0-4 years (80.3%, n = 53 vs. 19.7%, n = 13, p = 0.01). During the follow-up, data from 71.3% (n = 241) othe patients were available. Disease activity measured by PCDAI decreased in 47.7% (n = 115) of the patients, 40.7% (n = 98) of the patients were stable and increased in 11.6% (n = 28) of the patients. Patients with intermediate/severe disease at onset were more likely to have an active disease at the end of follow up, too (p = 0.00). Logistic regression analysis of the initial characteristics showed that the age at diagnosis, gender, initial location and initial extra-intestinal manifestation are not associated with the progression of the disease (p>0.05). Furthermore, drug treatment options could be identified from our data, which are associated with benefits for a milder course or remission. CONCLUSION: From 2000 to 2014, the health status of most pediatric patients with CD had improved or remained stable. Initial characteristics including age at diagnosis, initial localization and initial extra-intestinal manifestation are not associated with the progression of the disease, only the initial activity by PCDAI.

Human glycoprotein-2 expressed in Brunner glands - A putative autoimmune target and link between Crohn's and coeliac disease.

Glycoprotein 2 (GP2) is an autoantigen in Crohn's (CD) and coeliac disease (CeD). We assessed GP2-isoform (GP21-4)-expression in intestinal biopsies of paediatric patients with CD, CeD, ulcerative colitis (UC), and healthy children (HC). Transcription of GP21-4 was elevated in proximal small intestine in CeD and CD patients (only GP22/4) compared to jejunum (CeD/CD) and large bowel (CD). CeD patients demonstrated higher duodenal GP22/4-mRNA levels compared to HC/UC patients whereas CD patients showed higher GP24-mRNA levels compared to UC patients. Duodenal synthesis of only small GP2 isoforms (GP23/4) was demonstrated in epithelial cells in patients/HC and in Brunner glands (also large isoforms) with a more frequent apical location in CD/CeD patients. All four GP2 isoforms interacted with gliadin and phosphopeptidomannan. Gliadin digestion improved binding to GP2 isoforms. GP21-4 binding to CeD/CD-related antigens, elevated duodenal GP21-4-mRNA transcription, and GP2-protein secretion in Brunner glands of CeD/CD patients suggest an autoimmune CeD/CD link.

Novel mutation and expanding phenotype in IRF2BP2 deficiency.

OBJECTIVES: Inborn errors of immunity manifest with susceptibility to infection but may also present with immune dysregulation only. According to the European Society for Immunodeficiencies Registry about 50% of inborn errors of immunity are classified as common variable immunodeficiencies (CVID). In only few CVID patients are monogenic causes identified. IFN regulatory factor-2 binding protein 2 (IRF2BP2) is one of 20 known genes associated with CVID phenotypes and has only been reported in two families so far. We report another IRF2BP2-deficient patient with a novel pathogenic variant and phenotype and characterize impaired B cell function and immune dysregulation. METHODS: We performed trio whole-exome sequencing, determined B cell subpopulations and intracellular calcium mobilization upon B cell receptor crosslinking in B cells. T cell subpopulations, T cell proliferation and a type I IFN signature were measured. Colonoscopy and gastroduodenoscopy including histopathology were performed. RESULTS: The 33-year-old male presented with recurrent respiratory infections since childhood, colitis and RA beginning at age 25 years. We identified a novel de novo nonsense IRF2BP2 variant c.1618C>T; p.(Q540*). IgG deficiency was detected as consequence of a severe B cell differentiation defect. This was confirmed by impaired plasmablast formation upon stimulation with CpG. No serum autoantibodies were detected. Intracellular cytokine production in CD4+ T cells and CTLA4 expression on FOXP3+ Tregs were impaired. Type I IFN signature was elevated. CONCLUSION: The identified loss-of-function variant in IRF2BP2 severely impairs B cell development and T cell homeostasis, and may be associated with colitis and RA. Our results provide further evidence for association of IRF2BP2 with CVID and contribute to the understanding of the underlying pathomechanisms.

PR3-ANCAs Detected by Third-Generation ELISA Predicts Severe Disease and Poor Survival in Primary Sclerosing Cholangitis.

A highly sensitive detection of anti-neutrophil cytoplasmic antibodies to serine proteinase-3 (PR3-ANCAs) aids in the serological diagnosis of autoimmune liver disorders and the prediction of severity in primary sclerosing cholangitis (PSC). Here, we evaluate a novel third-generation ELISA for the detection of PR3-ANCAs. In total, 309 patients with PSC, 51 with primary biliary cholangitis (PBC), and 120 healthy blood donors (BD) were analyzed. For the survival analysis in PSC, the outcome was defined as liver-transplantation-free survival during the follow-up. Positive PR3-ANCA levels were found in 74/309 (24.0%) of patients with PSC. No BDs and one patient with PBC demonstrated PR3-ANCA positivity. PR3-ANCAs were revealed as independent predictors for a poor PSC outcome (study endpoint: liver transplantation/death, log-rank test, p = 0.02). PR3-ANCA positivity, lower albumin levels, and higher bilirubin concentrations were independent risks of a poor survival (Cox proportional-hazards regression analysis, p < 0.05). The Mayo risk score for PSC was associated with PR3-ANCA positivity (p = 0.01) and the disease severity assessed with a model of end-stage liver disease (MELD) and extended MELD-Na (p < 0.05). PR3-ANCAs detected by a third-generation ELISA are diagnostic and prognostic markers for PSC. Their wider use could help to identify patients who are at-risk of a more severe disease.

Current and projected incidence trends of pediatric-onset inflammatory bowel disease in Germany based on the Saxon Pediatric IBD Registry 2000-2014 -a 15-year evaluation of trends.

AIMS: An increasing number of children and adolescents worldwide suffer from inflammatory bowel disease (IBD) such as Crohn's disease (CD) and ulcerative colitis (UC). The present work aims to investigate the incidence, prevalence and future trends of IBD in children and adolescents in Saxony, Germany. METHODS: The Saxon Pediatric IBD Registry collected data on patients up to 15 years of age from all 31 pediatric hospitals and pediatric gastroenterologists in Saxony over a 15-year period (2000-2014). In 2019, an independent survey estimated a registry completeness of 95.7%. Age-standardized incidence rates (ASR) per 100,000 person-years (PY) and prevalence per 100,000 children and adolescents were calculated. Evaluation was also been performed in sex and age subgroups. Joinpoint and Poisson regression were used for trend analyses and projections. RESULTS: 532 patients with confirmed IBD during 2000-2014 were included in the epidemiological evaluation. 63.5% (n = 338) patients had CD, 33.1% (n = 176) had UC and 3.4% (n = 18) had unclassified IBD (IBD-U). The 15-year IBD prevalence was 111.8 [95%-CI: 102.3-121.3] per 100,000. The incidence ASR of IBD per 100,000 PY over the whole observation period was 7.5 [6.9-8.1]. ASR for the subtypes were 4.8 [4.3-5.3] for CD, 2.5 [2.1-2.9] for UC and 0.3 [0.1-0.4] for IBD-U. The trend analysis of ASR using the joinpoint regression confirmed a significant increase for incidence of IBD as well as CD. For IBD, the ASR per 100,000 PY increased from 4.6 [2.8-6.3] in 2000 to 8.2 [7.5-13.6] in 2014; projected incidence rates for IBD in Germany are 12.9 [6.5-25.5] in the year 2025 and 14.9 [6.7-32.8] in 2030, respectively. Thus, the number of new IBD diagnoses in Germany would more than triple (325%) in 2030 compared to 2000. The increase is expected to be faster in CD than UC, and be more in males than in females. The expected number of newly diagnosed children with IBD in Germany is projected to rise to about 1,584 [1,512-1,655] in 2025, and to about 1,918 [1,807-2,29] in 2030. CONCLUSION: The incidence of IBD in children and adolescents in Saxony increased at a similar rate as in other developed countries during the observation period. Given this trend, the health care system must provide adequate resources for the care of these young patients in the future.

Occurrence of Thromboembolism in Paediatric Patients With Inflammatory Bowel Disease: Data From the CEDATA-GPGE Registry.

Objective: Among patients with inflammatory bowel disease (IBD), the risk of thromboembolism (TE) is increased, representing a relevant cause of morbidity and mortality. In contrast to other extraintestinal IBD manifestations, TE receives much less attention because of its low incidence, estimated at merely 0.4-0.9% in hospitalised children with IBD. Methods: Cases with TE, as documented in the German-Austrian Paediatric IBD registry gesellschaft für pädiatrische gastroenterologie und ernährung - large paediatric patient registry (CEDATA-GPGE), were analyzed retrospectively. For all patients with signs of TE, a questionnaire was filled in by the treating paediatric gastroenterologist. Results: Over 10 years, 4,153 paediatric patients with IBD (0-18 years) were registered in the registry, and 12 of them identified with TE. Eight patients were diagnosed with ulcerative colitis (UC), three with Crohn's disease (CD), and one with IBD-unclassified. The median age at IBD diagnosis was 10 years and at the manifestation of TE 13 years, respectively, with a median latency to TE of 2 years. Prevalence of TE was 0.3%, with a significantly higher risk for patients with UC than CD (OR 5.9, CI 1.56-22.33, p = 0.008). More girls than boys were affected (f:m = 7:5) without reaching significance. Approximately 90% of patients experienced TE during active disease, with relevant cerebral and limb involvement in 6/12 patients. Various risk factors, e.g., hospitalisation, coagulopathy, or anaemia were identified. TE management included intensive care and surgery. Among the 12 patients, 11 recovered fully, in which one patient has focal epilepsy as a sequela. Conclusion: Paediatric patients with IBD have a substantially increased risk for TE. Risk factors, such as those identified should be considered when managing paediatric IBD and preventive measures for those hospitalised taken routinely. Initiating pharmacological thromboprophylaxis is challenging for the lack of published trials on efficacy and safety in paediatric IBD but should be considered carefully in each case.

Hyper-IgE and Carcinoma in CADINS Disease.

Background: Atopic dermatitis (AD) affects up to 25% of children and 10% of adults in Western countries. When severe or recurrent infections and exceedingly elevated serum IgE levels occur in AD patients, an inborn error of immunity (IEI) may be suspected. The International Union of Immunological Societies classification lists variants in different genes responsible for so-called Hyper-IgE syndromes. Diagnosing an underlying IEI may influence treatment strategies. Methods: Clinical and diagnostic workup of family members are presented including a detailed immunological description and histology of the carcinoma. Functional testing of the novel variant in CARD11 underlying 'CARD11-associated atopy with dominant interference of NF-kB signaling' (CADINS) was performed. Results: We report on an 18-year-old patient with a long-standing history of infections, accompanied by hypogammaglobulinemia, intermittent agranulocytosis, atopy, eosinophilia and colitis. The working diagnosis of common variable immunodeficiency was revised when a novel heterozygous CARD11 variant [c.223C>T; p.(Arg75Trp)] was identified. Functional studies confirmed this variant to have a dominant negative (DN) effect, as previously described in patients with CADINS. Five other family members were affected by severe atopy associated with the above variant, but not hypogammaglobulinemia. Malignancies occurred in two generations: an HPV-positive squamous cell carcinoma and a cutaneous T-cell lymphoma. So far, one patient is under treatment with dupilumab, which has shown marked benefit in controlling severe eczema. Conclusion: The phenotypic spectrum associated with heterozygous CARD11 DN mutations is broad. Partial T-cell deficiency, diminished IFN-γ cytokine and increased IL-4 production, were identified as disease-causing mechanisms. Malignant disease associated with germline CARD11 DN variants has only been reported sporadically. HPV vaccination in teenage years, and cytology screening analogous with routine cervical swabs may be recommended. Treatment with dupilumab, a monoclonal antibody blocking interleukin-4- and interleukin-13 signaling, may be of benefit in controlling severe and extended AD for some patients as reported for STAT3 loss-of-function.

Anti-Proteinase 3 Antibodies as a Biomarker for Ulcerative Colitis and Primary Sclerosing Cholangitis in Children.

OBJECTIVES: Anti-neutrophil cytoplasmic antibody (ANCA) directed against proteinase 3 (PR3) is a marker for granulomatosis with polyangiitis, but is also found in patients with inflammatory bowel disease (IBD), mainly ulcerative colitis (UC). The aim of our study was to investigate ANCA and PR3-ANCA in paediatric IBD. METHODS: We tested 326 paediatric IBD patients and 164 controls for anti-Saccharomyces cerevisiae antibodies (ASCA), ANCA (indirect immunofluorescence, IIF) and PR3-ANCA (chemiluminescence immunoassay). We applied the Paris classification for paediatric IBD and documented liver manifestations such as primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH). RESULTS: We found PR3-ANCA in 49/121 (40%) of UC, 20/187 (11%) of Crohn disease (CD) and 2/18 (11%) of IBD-unclassified (IBD-U) patients but in none of the controls. 54% UC and 12% CD patients were positive for ANCA (IIF). PR3-ANCA positive UC patients were characterised by more extensive disease (P = .070). Fourteen of 21 (67%) of UC patients with backwash ileitis were anti-PR3 ANCA-positive (P = .011). We diagnosed PSC or PSC/AIH in 19 UC and 3 IBD-U patients. Fifteen of 22 (68%) patients with PSC or PSC/AIH were anti-PR3-ANCA positive in contrast to 36 of 117 (32%) patients without PSC (P = .001). PR3-ANCA positive patients showed higher levels of gamma-glutamyl transferase, alanine transaminase and aspartate transferase (P < 0.001, 0.001, 0.006, respectively). Forty-seven percent of CD and 6% of UC patients were ASCA-IgA positive. PR3-ANCA-positive and -negative patients showed no significant differences concerning age at diagnosis, disease activity, need for drugs, and number of hospitalisations. CONCLUSIONS: Our study provides data for PR3-ANCA as a potential serological marker for paediatric UC and PSC.

[Chronic or severe enteropathy and immunodeficiency: be prepared for a rara avis]. / Chronische oder schwere Darmerkrankung und Immundefekt: Manchmal ist es doch ein Kolibri.

In the work-up of chronic enteropathies an underlying inborn error of immunity (IEI) should be considered in certain cases. IEI are rare, but approximately 10% of patients may present with symptoms of inflammatory bowel disease (IBD), which is a much more common entity. Patients with IEI associated IBD may show extraintestinal symptoms or signs, and are often refractory to conventional anti-inflammatory treatment. In case of early-onset bowel inflammation and other intestinal or extraintestinal manifestations, an IEI should be excluded. A small fraction of monogenic IEI can be amenable to targeted therapies, or even corrected by allogeneic stem cell transplantation. Therefore, early diagnosis is crucial. This paper shows examples of clinical - gastrointestinal as well as extraintestinal - signs and findings which require immunological and possibly genetic workup.

Pathogenic STX3 variants affecting the retinal and intestinal transcripts cause an early-onset severe retinal dystrophy in microvillus inclusion disease subjects.

Biallelic STX3 variants were previously reported in five individuals with the severe congenital enteropathy, microvillus inclusion disease (MVID). Here, we provide a significant extension of the phenotypic spectrum caused by STX3 variants. We report ten individuals of diverse geographic origin with biallelic STX3 loss-of-function variants, identified through exome sequencing, single-nucleotide polymorphism array-based homozygosity mapping, and international collaboration. The evaluated individuals all presented with MVID. Eight individuals also displayed early-onset severe retinal dystrophy, i.e., syndromic-intestinal and retinal-disease. These individuals harbored STX3 variants that affected both the retinal and intestinal STX3 transcripts, whereas STX3 variants affected only the intestinal transcript in individuals with solitary MVID. That STX3 is essential for retinal photoreceptor survival was confirmed by the creation of a rod photoreceptor-specific STX3 knockout mouse model which revealed a time-dependent reduction in the number of rod photoreceptors, thinning of the outer nuclear layer, and the eventual loss of both rod and cone photoreceptors. Together, our results provide a link between STX3 loss-of-function variants and a human retinal dystrophy. Depending on the genomic site of a human loss-of-function STX3 variant, it can cause MVID, the novel intestinal-retinal syndrome reported here or, hypothetically, an isolated retinal dystrophy.

Incidence trends of pediatric onset inflammatory bowel disease in the years 2000-2009 in Saxony, Germany-first results of the Saxon Pediatric IBD Registry.

AIMS: In developed countries, the incidence of inflammatory bowel disease (IBD) such as Crohn's disease (CD) and ulcerative colitis (UC) is increasing. Therefore, we aimed to investigate the incidence rates and trends over time in the population of children and adolescents in one of the federal states of Germany, in Saxony. METHODS: Over the 10-year period 2000-2009 all 31 children's hospitals and pediatric gastroenterologists, respectively in Saxony reported all IBD patients up to 15 years of age to the Saxon Pediatric IBD Registry. The completeness of the registry was estimated as 96.7% by independent surveys in the years 2005-2009. Incidence rates were presented as age-standardized incidence rates (ASR) regarding New European Standard Population 1990 per 100,000 person-years (PY) with 95% confidence intervals [CI]. Joinpoint and linear regression was used for trend analyses. RESULTS: 344 patients with confirmed IBD between 2000-2009 were included in the epidemiological evaluation: 212 (61.6%) patients with CD, 122 (35.6%) with UC and 10 (2.9%) with unclassified IBD (IBD-U). The ASR per 100,000 PY over the whole observation period was 7.2 [6.4-7.9] for IBD, 4.4 [3.8-5.0] for CD, 2.6 [2.1-3.0] for UC and 0.2 [0.1-0.3] for IBD-U. For IBD, the ASR per 100,000 PY increased from 4.6 [2.8-6.3] in 2000 to 10.5 [7.5-13.6] in 2009. The incidence trend analysis of ASRs using the joinpoint regression confirmed a significant increase of IBD as well as UC. The mean age at first diagnosis decreased significantly during the observation period from 11.5 (11.0-13.4) in 2000 to 9.6 (5.1-13.5) years in 2009. The median of the diagnostic latency among IBD patients was 3 months. CONCLUSION: The incidence of IBD in children and adolescents in Saxony was slightly higher than the average of other countries in the same time period and followed the trend towards a general increase of IBD. The age at diagnosis was subject to a very unfavorable downward trend.

Mutations in RPSA and NKX2-3 link development of the spleen and intestinal vasculature.

Idiopathic intestinal varicosis is a developmental disorder defined by dilated and convoluted submucosal veins in the colon or small bowel. A limited number of families with idiopathic intestinal varices has been reported, but the genetic cause has not yet been identified. We performed whole-exome and targeted Sanger sequencing of candidate genes in five intestinal varicosis families. In four families, mutations in the RPSA gene were found, a gene previously linked to congenital asplenia. Individuals in these pedigrees had intestinal varicose veins and angiodysplasia, often in combination with asplenia. In a further four-generation pedigree that only showed intestinal varicosities, the RPSA gene was normal. Instead, a nonsense mutation in the homeobox gene NKX2-3 was detected which cosegregated with the disease in this large family with a LOD (logarithm of the odds) score of 3.3. NKX2-3 is a component of a molecular pathway underlying spleen and gut vasculature development in mice. Our results provide a molecular basis for familial idiopathic intestinal varices. We provide evidence for a relationship between the molecular pathways underlying the development of the spleen and intestinal mucosal vasculature that is conserved between humans and mice. We propose that clinical management of intestinal varices, should include assessment of a functional spleen.

Orbital inflammation and colitis in pediatric IgG4-related disease: A case report and review of the literature.

IgG4-related disease (IgG4-RD) is an inflammatory disorder characterized by tumor-like swelling in one or more organs, elevated serum IgG4 levels, and histological alterations with infiltration of IgG4-positive plasma cells. IgG4-RD is rare and likely underdiagnosed in children. We report a case of a 16-year-old girl with IgG4-positive colitis that developed weeks after IgG4-related ophthalmic disease and discuss diagnosis and treatment in the context of the literature available. Since the pathophysiology of IgG4-RD is unknown, treatment options are empiric and, for the most part, untargeted. Systemic corticosteroid treatment is the basis of anti-inflammatory treatment in IgG4-RD and induced early remission in our patient. During corticosteroid taper, the patient developed weight loss and intestinal inflammation. Histopathological assessment of the intestinal walls confirmed IgG4-positive colitis. Immune-modulating treatment with non-biologic (e.g., methotrexate (MTX) and mycophenolate mofetil) or biologic (rituximab) disease-modifying antirheumatic drugs has been reported in treatment refractory or corticosteroid-dependent patients. The patient responded to treatment with anti-inflammatory therapy with food rich in TGF-ß2 (modulen) and MTX. This is one of the first pediatric patients reported with IgG4-related colitis extending the phenotype of pediatric IgG4-RD. International collaboration to prospectively document clinical presentation and treatment responses may help to further establish the phenotype and treatment options and to raise awareness for IgG4-RD.

Defining clinical subgroups and genotype-phenotype correlations in NBAS-associated disease across 110 patients.

PURPOSE: Pathogenic variants in neuroblastoma-amplified sequence (NBAS) cause an autosomal recessive disorder with a wide range of symptoms affecting liver, skeletal system, and brain, among others. There is a continuously growing number of patients but a lack of systematic and quantitative analysis. METHODS: Individuals with biallelic variants in NBAS were recruited within an international, multicenter study, including novel and previously published patients. Clinical variables were analyzed with log-linear models and visualized by mosaic plots; facial profiles were investigated via DeepGestalt. The structure of the NBAS protein was predicted using computational methods. RESULTS: One hundred ten individuals from 97 families with biallelic pathogenic NBAS variants were identified, including 26 novel patients with 19 previously unreported variants, giving a total number of 86 variants. Protein modeling redefined the ß-propeller domain of NBAS. Based on the localization of missense variants and in-frame deletions, three clinical subgroups arise that differ significantly regarding main clinical features and are directly related to the affected region of the NBAS protein: ß-propeller (combined phenotype), Sec39 (infantile liver failure syndrome type 2/ILFS2), and C-terminal (short stature, optic atrophy, and Pelger-Huët anomaly/SOPH). CONCLUSION: We define clinical subgroups of NBAS-associated disease that can guide patient management and point to domain-specific functions of NBAS.

Identification of Chitinase-3-Like Protein 1 as a Novel Neutrophil Antigenic Target in Crohn's Disease.

BACKGROUND AND AIMS: There is an increasing incidence of inflammatory bowel disease [IBD]. Autoimmune responses are involved in the pathophysiology of IBD, but their underlying pathways and target antigens have not yet been fully elucidated. METHODS: Autoantigenic targets in IBD were identified after separation of whole cell proteins isolated from neutrophils using two-dimensional electrophoresis and matrix assisted laser desorption ionization - time of flight mass spectrometry-based protein identification of the spots that displayed Western blotting signals with anti-neutrophil cytoplasmic antibody-positive sera. The prevalence of IgG, IgA and secretory IgA [sIgA] to chitinase 3-like protein 1 [CHI3L1] was analysed by enzyme-linked immunosorbent assays using recombinant CHI3L1 in 110 patients with Crohn's disease [CD], 95 with ulcerative colitis [UC], 126 with coeliac disease [CeD] and 86 healthy controls [HCs]. RESULTS: The 18-glycosylhydrolase family member CHI3L1 was identified as a neutrophil autoantigenic target. CD patients displayed significantly higher levels of IgG to CHI3L1 than patients with UC and CeD (p < 0.0001, respectively). IgA and sIgA to CHI3L1 was significantly higher in CD than in UC, CeD and HCs [p < 0.0001, respectively]. IgA and sIgA to CHI3L1 demonstrated the highest prevalence in CD [25.5%, 28/110; and 41.8%%, 46/110] compared to HCs [2.3%, 2/86; and 4.7%%, 4/86; p = 0.0015 and p < 0.0001] and are associated with a more complicated progression of CD. CONCLUSION: CHI3L1 is a novel neutrophil autoantigenic target in CD. IgA and sIgA to CHI3L1 may serve as novel markers for CD and may facilitate the serological diagnosis of IBD.

Novel VPS33B mutation in a patient with autosomal recessive keratoderma-ichthyosis-deafness syndrome.

Autosomal recessive keratoderma-ichthyosis-deafness (ARKID) syndrome is a rare multisystem disorder caused by biallelic mutations in VPS33B; only three patients have been reported to date. ARKID syndrome is allelic to arthrogryposis-renal dysfunction-cholestasis (ARC) syndrome (MIM #208085), a severe disorder with early lethality whose phenotypic characteristics also include ichthyosis, hearing loss, severe failure to thrive, platelet dysfunction and osteopenia. We report on an 11-year-old male patient with ARKID syndrome and compound heterozygous VPS33B mutations, one of which [c.1440delG; p.(Arg481Glyfs*11)] was novel. Clinical features of this patient included ichthyosis, palmoplantar keratosis, hearing loss, intellectual disability, unilateral hip dislocation, microcephaly and short stature. He also had copper hepatopathy and exocrine pancreatic insufficiency, features that have so far been associated with neither ARKID nor ARC syndrome. The patient broadens the clinical and molecular spectrum of ARKID syndrome and contributes to genotype-phenotype associations of this rare disorder.