Almuthe Hauer

Antibodies against deamidated gliadin as new and accurate biomarkers of childhood coeliac disease.

Objectives: Assays of tissue transglutaminase antibodies (anti-tTG) represent the cornerstone of serological coeliac disease (CD) diagnostics. Assays of antibodies against native gliadin (anti-nGli) lost importance due to low validity. We investigated the performance of new assays for antibodies against deamidated gliadin (anti-dGli) in childhood CD. Methods: We retrospectively compared children (142 with active CD and 160 without CD, diagnosis confirmed or excluded by intestinal biopsy) concerning (immunoglobulin [Ig] G and IgA) anti-nGli, anti-tTG, and 2 different anti-dGli assays. Results: IgG-anti-dGli1, IgG-anti-dGli2, and IgA-anti-tTG performed similarly. Area under the receiver-operating characteristic curve (AUC) was 98.6%, 98.9%, and 97.9%; accuracy was 94.7%, 95.7%, and 96.7%. Anti-dGli1 and anti-dGli2 (IgG and IgA) and IgA-anti-tTG performed significantly better than IgA-anti-nGli and IgG-anti-nGli. Both IgG-anti-dGli showed higher AUC and accuracy than IgA-anti-dGli and IgG-anti-tTG. Combined evaluation of IgA-anti-tTG with one of the IgG-anti-dGli tests reduced the rate of falsely classified patients. At enhanced cutoff (specificity >99%), sensitivity was above 67% for both IgG-anti-dGli and IgA-anti-tTG. If IgA-anti-tTG assay was combined with one of the IgG-anti-dGli tests, then the fraction of patients identified with more than 99% specificity as coeliacs increased significantly above 84.5%. Combined evaluation of the 2 IgG-anti-dGli tests did not improve the performance. Conclusions: The new IgA and IgG-anti-dGli tests outperform conventional anti-nGli assays. The validity of IgG-anti-dGli cannot be distinguished from IgA-anti-tTG. It should be studied prospectively whether antibody assays could replace biopsy in diagnosis of CD in a substantial segment of children.

Childhood Onset Inflammatory Bowel Disease: Predictors of Delayed Diagnosis from the CEDATA German-Language Pediatric Inflammatory Bowel Disease Registry

OBJECTIVES To examine predictors of delayed diagnosis of inflammatory bowel disease in children and adolescents. STUDY DESIGN A total of 2,436 patients (age 0-18 years) with Crohns disease, ulcerative colitis, or unclassified colitis were included from 53 pediatric gastroenterologists. Predictors were examined with the proportional hazards model, presented as hazard ratios (HR) with 95% confidence intervals. HR < 1.0 represent factors associated with late diagnosis. RESULTS Median time to diagnosis was 4 (2-8) months. Crohns disease (HR 0.62; 0.56-0.68), and within Crohns disease, ileal disease (HR 0.77, 95% confidence interval 0.67 to 0.89) were associated with delayed diagnosis. Chances for early diagnosis increased with increasing age (HR 1.07 per year of age; 1.06 to 1.08). There was also an effect by center (HR 0.63, 0.52 to 0.67), but not by sex or country (Austria vs Germany). Growth failure was more common in those cases with delayed diagnosis. CONCLUSIONS There is still concern about delays in the diagnosis of inflammatory bowel disease in the very young and in children with small bowel disease. Inequalities of care by region require further investigation.

Prevention and Treatment of Tube Dependency in Infancy and Early Childhood

Tube dependency is recog- nized as an unintended result of long- term tube feeding in infants and young children. The condition involves dis- turbing side effects such as vomiting, gagging, and active food refusal. It pre- vents infants from making the transi- tion from tube to oral feeding and from starting to learn to eat in the absence of any medical indication for contin- uation of enteral feeding. Tube depen- dency can have a destructive impact on the childs development, even in cases when the nutritional influence might be beneficial. The authors set up recom- mendations for the prevention of tube dependency and suggest guidelines for weaning tube-dependent children based on the results of the Graz pro- gram and satellite programs using a similar model. A sample of 221 tube- dependent patients aged 4 months to 15 years of age provided the clinical study group on which this article is based. Begun in 1987, a comprehensive tube- weaning program was developed on the basis of clinical experience and encoun- ters with more than 430 tube-dependent children in 20 years, resulting in a suc- cess rate of 78/81 (96% for 2007) and 79/84 (94% for 2008). Placement must be preceded by clear criteria and a deci- sion as to the indicated nutritional goal and time of use. The placement of a temporary tube must generate a plan covering maintenance issues, including time, method, and team for weaning. Aspects of tube feeding that go beyond purely medical and nutritional issues need to be considered to minimize the frequency and severity of unintended tube dependency in early childhood.

Malignancy and mortality in pediatric patients with inflammatory bowel disease: a multinational study from the porto pediatric IBD group.

Background:The combination of the severity of pediatric-onset inflammatory bowel disease (IBD) phenotypes and the need for intense medical treatment may increase the risk of malignancy and mortality, but evidence regarding the extent of the problem is scarce. Therefore, the Porto Pediatric IBD working group of ESPGHAN conducted a multinational-based survey of cancer and mortality in pediatric IBD. Methods:A survey among pediatric gastroenterologists of 20 European countries and Israel on cancer and/or mortality in the pediatric patient population with IBD was undertaken. One representative from each country repeatedly contacted all pediatric gastroenterologists from each country for reporting retrospectively cancer and/or mortality of pediatric patients with IBD after IBD onset, during 2006–2011. Results:We identified 18 cases of cancers and/or 31 deaths in 44 children (26 males) who were diagnosed with IBD (ulcerative colitis, n = 21) at a median age of 10.0 years (inter quartile range, 3.0–14.0). Causes of mortality were infectious (n = 14), cancer (n = 5), uncontrolled disease activity of IBD (n = 4), procedure-related (n = 3), other non-IBD related diseases (n = 3), and unknown (n = 2). The most common malignancies were hematopoietic tumors (n = 11), of which 3 were hepatosplenic T-cell lymphoma and 3 Ebstein–Barr virus–associated lymphomas. Conclusions:Cancer and mortality in pediatric IBD are rare, but cumulative rates are not insignificant. Mortality is primarily related to infections, particularly in patients with 2 or more immunosuppressive agents, followed by cancer and uncontrolled disease. At least 6 lymphomas were likely treatment-associated by virtue of their phenotype.

Antibodies in the Diagnosis of Coeliac Disease: A Biopsy-Controlled, International, Multicentre Study of 376 Children with Coeliac Disease and 695 Controls

Diagnosis of coeliac disease (CD) relies on a combination of clinical, genetic, serological and duodenal morphological findings. The ESPGHAN suggested that biopsy may not be necessary in all cases. New guidelines include omission of biopsy if the concentration of CD-specific antibodies exceeds 10 times the upper limit of normal (10 ULN) and other criteria are met. We analysed the 10 ULN criterion and investigated multiple antibody-assays. Serum was collected from 1071 children with duodenal biopsy (376 CD patients, 695 disease-controls). IgA-antibodies to tissue transglutaminase (IgA-aTTG), IgG-antibodies to deamidated gliadin peptides (IgG-aDGL) and IgA-endomysium antibodies (IgA-EMA) were measured centrally. We considered 3 outcomes for antibody test procedures utilizing IgA-aTTG and/or IgG-aDGL: positive (≥10 ULN, recommend gluten-free diet), negative (<1 ULN, no gluten-free diet) or unclear (perform biopsy). Positive (PPV) and negative (NPV) predictive values were based on clear test results. We required that they and their lower confidence bounds (LCB) be simultaneously very high (LCB >90% and PPV/NPV >95%). These stringent conditions were met for appropriate antibody-procedures over a prevalence range of 9–57%. By combining IgG-aDGL with IgA-aTTG, one could do without assaying total IgA. The PPV of IgG-aDGL was estimated to be extremely high, although more studies are necessary to narrow down the LCB. The proportion of patients requiring a biopsy was <11%. The procedures were either equivalent or even better in children <2 years compared to older children. All 310 of the IgA-aTTG positive children were also IgA-EMA positive. Antibody-assays could render biopsies unnecessary in most children, if experienced paediatric gastroenterologists evaluate the case. This suggestion only applies to the kits used here and should be verified for other available assays. Confirming IgA-aTTG positivity (≥10 ULN) by EMA-testing is unnecessary if performed on the same blood sample. Prospective studies are needed.

New Developments in Serodiagnosis of Childhood Celiac Disease: Assay of Antibodies against Deamidated Gliadin

Antibodies to deamidated gliadin present a new tool in the diagnosis of celiac disease (CD). In children, the ELISA for the determination of IgG antibodies to (deamidated) gliadin‐analogous fusion peptides (GAF3X) has a superior performance compared to the ELISA for the determination of antibodies against native gliadin and is comparable to assays for IgA antibodies against tissue transglutaminase (IgA‐anti‐tTG). The combined investigation of IgG antibodies to GAF3X (IgG‐anti‐GAF3X) and IgA‐anti‐tTG significantly increases the fraction of children definitely identified as either CD or non‐CD patients. The new IgG‐anti‐GAF3X ELISA was also able to detect CD in three cases of IgA deficiency and in two cases of latent CD and was also useful in the diagnosis of children younger than 2 years of age.

Use of Biosimilars in Paediatric Inflammatory Bowel Disease: A Position Statement of the ESPGHAN Paediatric IBD Porto Group.

ABSTRACT Because the patents for biopharmaceutical monoclonal antibodies have or soon will expire, biosimilars are coming to the market. This will most likely lead to decreased drug costs and so easier access to these expensive agents. Extrapolation, however, of the limited available clinical data from adults with rheumatologic diseases to children with inflammatory bowel disease (IBD) should be done with caution and needs some considerations. Postmarketing surveillance programs for efficacy, safety, and immunogenicity should become mandatory in children with IBD using biosimilars, as for all biological drugs.

Tube Dependence A Reactive Eating Behavior Disorder

This article focuses on the issue of tube dependence (TD) in infancy and early childhood. The condition occurs in patients after temporary tube feeding and must be considered as an unintended side effect of modern treatment practices affecting young patients reactively. Whereas some recent literature has described small samples of enterally fed children being exposed to certain weaning programs, the particular phenomenon of unintentional dependence has not been discussed. A tube-dependent child remains tube fed although his/her medical condition and developmental potential would allow the transition to oral nutrition. Children with TD show characteristic symptoms such as food refusal and opposition to any oral feeding attempts. They often suffer from additional episodes of vomiting, nausea, gagging, and retching and in some cases develop severe failure to thrive. Parents of affected children get involved as codependents engaged in constant preparations of the next tube feeds. In this situation, families c...

Inflammatory Bowel Disease Alters Intestinal Bile Acid Transporter Expression

The enterohepatic circulation of bile acids (BAs) critically depends on absorption of BA in the terminal ileum and colon, which can be affected by inflammatory bowel disease (IBD). Diarrhea in IBD is believed to result in part from BA malabsorption (BAM). We explored whether IBD alters mRNA expression of key intestinal BA transporters, BA detoxifying systems, and nuclear receptors that regulate BA transport and detoxification. Using real-time polymerase chain reaction, mucosal biopsy specimens from the terminal ileum in Crohn’s disease (CD) patients and from the descending colon in ulcerative colitis (UC) patients were assessed for mRNA expression. Levels were compared with healthy controls. The main ileal BA uptake transporter, the apical sodium dependent bile acid transporter, was downregulated in active CD and UC and in CD in remission. Other significant changes such as repression of breast cancer–related protein and sulphotransferase 2A1 were seen only during active disease. In UC, pancolitis (but not exclusively left-sided colitis) was associated with altered expression of major BA transporters [multidrug resistance–associated protein 3 (MRP3), MRP4, multidrug resistance gene 1, organic solute transporter α/β] and nuclear receptors (pregnane X receptor, vitamin D receptor) in the descending colon. UC pancolitis leads to broad changes and CD ileitis to selective changes in intestinal BA transporter expression. Early medical manipulation of intestinal BA transporters may help prevent BAM.

Thrombin generation in pediatric patients with Crohn's disease

Background: Patients with inflammatory bowel disease (IBD) have an increased risk of thromboembolic complications. The pathogenesis of IBD is not really clear and a high thrombin activity might contribute to the pathogenesis. We measured thrombin generation by means of calibrated automated thrombography (CAT), a new tool better reflecting overall hemostasis, in children with Crohns disease (CD) during active and inactive disease and compared it to conventional markers of activity. We wanted to see whether children with CD have a higher potential for thrombin generation and if there is a correlation between hypercoagulability and disease activity. Methods: Plasma samples were collected from 22 patients with CD and from 61 healthy children. Thrombin generation was measured by means of CAT. The disease activity was estimated using the Pediatric Crohns Disease Activity Index (PCDAI). In addition, F1+2, TAT, tissue factor pathway inhibitor (TFPI), fibrinogen, prothrombin (FII), antithrombin (AT), erythrocyte sedimentation rate (ESR), platelet count, &agr;2‐globulin, and orosomucoide were measured. Results: In all patients we found a significantly higher endogenous thrombin potential (ETP) and higher peak values during active disease. In accordance with this we also found significantly higher mean ETP values during active disease compared with the control group. We observed a significantly positive correlation between PCDAI and thrombin generation parameters. Conclusions: Our study clearly shows that the active state of CD in children is associated with the potential for high thrombin generation, but this seems to be caused mainly by the inflammatory process and not by a preexisting propensity for high thrombin generation. (Inflamm Bowel Dis 2011;)