Ondrej Hradsky

Impact of Anti–Tumor Necrosis Factor Alpha Antibodies Administered to Pregnant Women With Inflammatory Bowel Disease on Long-term Outcome of Exposed Children

Background:Prenatal exposure to anti–tumor necrosis factor &agr; (TNF-&agr;) antibodies seems to be safe for fetal development. Data on long-term outcome of exposed children are missing. Our aim was to assess long-term postnatal development of children exposed to anti–TNF-&agr; during pregnancy. Methods:Consecutive children aged ≥12 months exposed to anti-TNFs prenatally for maternal inflammatory bowel disease in 3 centers in the Czech Republic were enrolled. Data on psychomotor development, infections, antibiotics, vaccination, and allergy were retrospectively obtained from mothers, treating pediatricians, and childrens vaccination cards. Furthermore, standardized laboratory tests on humoral and cellular immunity were performed. Results:Twenty-five children exposed to biologicals were included (median age, 34 mo; range, 14–70 mo). All children had normal growth, and all but 1 had normal psychomotor development. Majority (80%) experienced at least 1 infection (mainly respiratory), and 60% of infants received antibiotics, 32% of those within the first year of life. Vaccination was undertaken according to vaccination protocol to 23 infants (92%). Fifteen children also had tuberculosis vaccination without serious complication. Immunological investigation was performed with 17 children (68%). Cellular immunity was normal in all infants, and 7 children had mild decrease in IgA and/or IgG immunoglobulins without clinical significance. All children had a detectable serologic response to vaccination. Conclusions:Exposure to anti–TNF-&agr; antibodies seems to be safe for growth and psychomotor development of children, although clinical significance of relatively high frequency of infections and antibiotic use among infants remains questionable because of the lack of a control group. Continuous follow-up of exposed children is absolutely warranted.

Infliximab dependency in children with Crohn's disease

Background  Recently, infliximab dependency has been described.

Variants of CARD15, TNFA and PTPN22 and susceptibility to Crohn’s disease in the Czech population: high frequency of the CARD15 1007fs

Crohns disease (CD) has been shown to be associated with the variants in the CARD15 gene as well as in other genes involved in the immune response. The frequencies of the variants profoundly differ among populations and so does the associated risk. We examined the associations of variants in the CARD15, TNFA and PTPN22 genes with pediatric-onset and adult-onset CD in the Czech population. Genotype, phenotype and allelic frequencies were compared between 345 patients with CD (136 pediatric-onset and 209 adult-onset patients) and 501 unrelated healthy controls. At least one minor allele of the CARD15 gene was carried by 46% patients and only 21% control subjects (OR = 3.2, 95% CI 2.4-4.4). In a multiple logistic regression model, the strongest association with CD was found for the 1007fs variant (OR = 4.6, 95% CI 3.0-7.0), followed by p.G908R (OR = 2.9, 95% CI 1.5-5.7) and p.R702W (OR = 1.7, 95% CI 1.0-2.9), while no independent association was found for the remaining variants in the CARD15 gene (p.268S, p.955I and p.289S), for the p.R620W variant in the PTPN22 gene or for the g.-308G>A variant in the TNFA gene. The age at CD onset was strongly modified by positivity for the 1007fs allele: it was present in 42% pediatric-onset and only 25% adult-onset patients. In conclusion, we report a high frequency of the minor allele of the CARD15 1007fs polymorphism in the Czech population and a strong effect of this allele on the age at disease onset.

The CTLA4 variants may interact with the IL23R- and NOD2-conferred risk in development of Crohn's disease

BackgroundThe CTLA4 (cytotoxic T-lymphocyte antigen 4) gene is associated with several immunopathologic diseases and because of its important immuno-regulatory role it may be considered also a plausible candidate for a genetic association with inflammatory bowel diseases. Previously published studies found no association of CTLA4 with Crohns disease itself, but some indicated an association with its subphenotypes. The aim of this study was to assess the association in the Czech population, using a set of markers shown to associate with other diseases.MethodsSix polymorphisms within the CTLA4 region were investigated in 333 patients with Crohns disease and 482 unrelated healthy controls, all Caucasians of Czech origin. The genotypes of the SNPs were determined using the TaqMan SNP genotyping assays. Haplotypes were reconstructed using an expectation-maximization algorithm, and their association with the condition was assessed using log-linear modeling. Then, potential interactions were tested between the CTLA4 variants and other genetic factors known to confer the disease susceptibility.ResultsNo crude associations with Crohns disease were found for the tested CTLA4 variants under the log-additive or dominant models. However, when stratified for the genetic risk conferred by the variants in the NOD2 (the p.Leu1007fsX1008, rs5743293) or the IL23R (p.R381Q, rs11209026), a significant negative association emerged for the minor alleles of CTLA4 CT60 (rs3087243), JO31 (rs11571302), JO27-1 (rs11571297) polymorphisms. This negative association with CTLA4 was apparent only in the strata defined by presence minor alleles at the NOD2 rs5743293 (here the CTLA4 CT60 A coffered an OR = 0.43, 95%CI 0.19 - 0.95 for the presence of CT60 A), or IL23R rs11209026 (here the OR for presence of CT60 A was 0.23, 95%CI 0.07 - 0.71). We observed this effect also for the haplotype consisting of minor alleles of the three tightly linked CTLA4 markers. Furthermore, this haplotype was associated with the younger age at diagnosis (OR 1.52, 95%CI 1.09 - 2.11, p = 0.014).ConclusionsA protective effect of a CTLA4 haplotype was unmasked after stratification for the risk variants in the NOD2 and IL23R genes, and may point towards the biological relevance of the molecule in the pathogenesis of the disease.

Disease activity is an important factor for indeterminate interferon-γ release assay results in children with inflammatory bowel disease.

Background: Interferon-&ggr; release assay (IGRA) is widely used for screening of latent tuberculosis (TB) before and during biological therapy (BT). An indeterminate result of IGRA represents a limitation in the management of inflammatory bowel disease (IBD). Data on factors influencing IGRA results are scarce in children. The aim of the study was to identify factors influencing IGRA results in children with IBD. Methods: Seventy-two children with IBD (59 Crohn disease, 11 ulcerative colitis, 2 IBD-unclassified) indicated for BT were tested for TB infection (history, TB skin test, chest radiograph, IGRA; QuantiFERON—TB Gold in tube [QFT]) and consecutively retested using QFT in 1-year intervals. Results: We recorded 165 results of QFT (3% positive, 87% negative, and 10% indeterminate results). During follow-up we identified 4 conversions of negative QFT to positivity (3%) and 4 reversions (4%). Patients with indeterminate results of QFT had significantly lower actual weight-for-height z score (P = 0.022), higher platelet count (P = 0.00017), and lower levels of serum albumin (P = 0.015) compared with patients with positive or negative QFT. Indeterminate QFT was associated with corticosteroid treatment, BT, and disease activity, but not with treatment by immunomodulators. In a subanalysis of patients with Crohn disease alone, Pediatric Crohns Disease Activity Index was identified as single independent risk factor for indeterminate results (P = 0.00037). Conclusions: Although corticosteroid treatment is traditionally considered to be the main risk factor for indeterminate results of IGRA, the disease activity of IBD has even more profound effects on the results.

The relationship between serum bilirubin and Crohn's disease.

Background:The oxidative stress is thought to play an important role in Crohn’s disease (CD). As serum bilirubin represents the major endogenous antioxidant, this article aimed to evaluate in a clinical study, whether serum bilirubin levels and genes affecting its systemic concentrations are associated with CD. Methods:This exploratory case-control study was based on pediatric (n = 119) and adult (n = 504) patients with CD and 370 appropriate healthy control subjects. The (GT)n and (TA)n dinucleotide variations in heme oxygenase 1 (HMOX1) and bilirubin UDP-glucuronosyl transferase (UGT1A1) gene promoters were determined by fragment analysis. Serum bilirubin levels were compared in a subset of 90 cases and 229 controls, for whom biochemical data were available. Results:Substantially lower serum bilirubin levels were detected in patients with CD compared with controls (7.4 versus 12.1 &mgr;mol/L, P < 10−6). Serum bilirubin levels were significantly lower in patients with CD within all UGT1A1*28 genotypes (P < 0.05). UGT1A1*28 homozygotes with wild-type NOD2 gene variant exhibited significant delay in CD manifestation (P = 0.004), while the protective effect of UGT1A1*28 homozygosity was lost in those patients with mutated NOD2 gene. No associations between CD risk and individual HMOX1 gene variants were observed. Conclusions:CD is associated with significantly low serum bilirubin levels, most likely as a result of increased oxidative stress accompanying this inflammatory disease. UGT1A1*28 allele homozygosity, responsible for higher bilirubin levels, seems to be an important modifier of CD manifestation.

Two independent genetic factors responsible for the associations of the IBD5 locus with Crohn's disease in the Czech population

Background: The role of the IBD5 locus in development of Crohns disease (CD) has not been clarified. In the Czech population we examined its genetic association using variants of the SLC22A4 (rs1050152), SLC22A5 (rs2631367), two single nucleotide polymorphisms (SNPs) shown to be associated with CD in genome‐wide studies (rs6596075 and rs2188962), and four SNPs previously shown to tag the haplotype blocks 4, 7, 9, 10 of the IBD5 locus (IGR2063b_1, IGR2230a_1, IGR100Xa_1, IGR3236a_1). Methods: The genotype, phenotype, and allelic frequencies were compared between 469 unrelated patients with CD (177 pediatric‐onset, 292 adult‐onset) and 470 unrelated healthy controls, all Caucasians of Czech ancestry. Results: The most significant difference between patients and controls was found for the SNP rs6596075 (odds ratio [OR] = 0.70 for the G allele; 95% CI 0.52‐0.94) in the dominant model and SNP IGR2063b_1 (OR = 1.38 for the G allele; 95% CI 1.14‐1.67) in the log‐additive model. We found a strong linkage disequilibrium across the IBD5 locus except rs6596075. The haplotype consisting of minor alleles of all tested SNPs except rs6596075 was carried by 31% patients and 23% control subjects (OR = 1.35, 95% CI 1.06‐1.72). The association of variants in SLC22A4 and SLC22A5 was dependent on this risk haplotype, while the strong association of the rs6596075 was seemingly independent. In the analysis of subphenotypes we found only an association of the penetrating disease with rs6596075 (OR = 2.13; 95% CI 1.31‐3.47). Conclusions: Our study confirms the importance of IBD5 in determining CD susceptibility, and demonstrates that two independent genetic factors may be responsible for the association observed within this locus. (Inflamm Bowel Dis 2010)

Association of IL23R p.381Gln and ATG16L1 p.197Ala with Crohn disease in the Czech population.

Objectives: An association of variants in the genes encoding the interleukin 23 receptor (IL23R, p.Arg381Gln, rs11209026), and the autophagy-related gene 16-like 1 (ATG16L1, p.Ala197Thr, rs2241880) with Crohn disease (CD) was identified by whole genome association studies, and subsequently confirmed by other works. The aim of this study was to assess this association in the Czech population. Subjects and Methods: In a case-control study 333 patients with CD (137 paediatric and 196 adult-onset) and 499 unrelated healthy controls were genotyped using TaqMan SNP assays. Results: The IL23R p.381Gln allele was protective against CD in the Czech population (allelic frequency 3.2% in patients vs 5.5% in control subjects; OR 0.56, 95% CI 0.33–0.93, P = 0.02). ATG16L1 p.197Ala allele conferred increased risk of CD (allelic frequency 60% in patients vs 51% in controls; OR 1.25, 95% CI 1.02–1.52, P = 0.03). There was no appreciable difference in the effect of the associated alleles across the strata of CARD15-conferred risk. The IL23R and ATG16L1 variants did not influence the age at diagnosis, and in the genotype-phenotype analysis, the only detected association was a weak one between IL23R p.381Gln and involvement of the upper gastrointestinal tract (uncorrected P = 0.031). Conclusions: We confirmed the role of IL23R and ATG16L1 in the CD susceptibility in the Czech population, and found a weak protective effect of IL23R p.381Gln against upper gastrointestinal tract involvement.

Supplementation with 2000 Iu of Cholecalciferol Is Associated with Improvement of Trabecular Bone Mineral Density and Muscle Power in Pediatric Patients with Ibd

Background: Inflammatory bowel diseases (IBD) are associated with altered bone health and increased risk for fractures. Vitamin D deficiency is frequently found in IBD; however, the effect of vitamin D supplementation on bone health of children with IBD is poorly understood. We aimed to observe the changes in volumetric bone density and dynamic muscle functions after vitamin D substitution in a cohort of pediatric patients with IBD. Methods: This was a prospective observational study of 55 patients (aged 5–19 years) with IBD. Bone quality was assessed using peripheral quantitative computed tomography and muscle functions by jumping mechanography at baseline and after a median of 13.8 (interquartile range, 12.0–16.0) months of daily substitution of 2000 IU of cholecalciferol. Results: Median serum levels of 25-hydroxyvitamin D increased from 58 nmol/L at the baseline visit to 85 nmol/L at the last follow-up visit (P < 0.001); no signs of overdose were reported. The Z-scores of trabecular bone mineral density, cortical bone cross-sectional area, and maximal muscle power improved significantly during the follow-up period (+0.5, P = 0.001, +0.3, P = 0.002 and +0.5, P = 0.002, respectively). Cholecalciferol substitution was positively associated with trabecular bone mineral density and maximal muscle power (estimates 0.26, 95% confidence interval 0.14–0.37, P < 0.0001 and 0.60, 95% confidence interval 0.32–0.85, P < 0.0001, respectively) but not with the Strength–Strain Index or maximal muscle force (Fmax). Conclusions: We observed an improvement in bone and muscle parameters after cholecalciferol substitution in pediatric patients with IBD. Therefore, vitamin D substitution can be considered in such patients.

Substantial proportion of MODY among multiplex families participating in a Type 1 diabetes prediction programme

Patients with maturity‐onset diabetes of the young (MODY) might be over‐represented in families with histories of Type 1 diabetes. Our aim was to re‐evaluate families participating in the Czech T1D Prediction Programme (PREDIA.CZ) with at least two members affected with diabetes to assess the proportion of MODY among these families and determine its most significant clinical predictors.