Atopic Dermatitis in Early Childhood and Risk of Inflammatory Bowel Disease: A Scandinavian Birth Cohort Study.

OBJECTIVE: To examine the association between early-life atopic manifestations and later risk of inflammatory bowel disease (IBD), for which prospective data are scarce. STUDY DESIGN: The population-based All Babies in Southeast Sweden (ABIS) and Norwegian Mother, Father, and Child (MoBa) cohorts follow children from birth (ABIS 1997-1999; MoBa 2000-2009) to the end of 2021. Based on validated questionnaires, parents prospectively reported information on asthma, food-related allergic symptoms, atopic dermatitis, and allergic rhinitis by age 3. IBD was defined by ≥ 2 diagnostic records in the national health registries. Cox regression estimated hazard ratios adjusted (aHRs) for parental IBD, atopy, education level, smoking habits, and national origin. Cohort-specific estimates were pooled using a random-effects model. RESULTS: We compiled data on 83 311 children (ABIS, n = 9041; MoBa, n = 74 270). In over 1 174 756 person-years of follow-up, 301 participants were diagnosed with IBD. Children with atopic dermatitis at age 3 had an increased risk of IBD (pooled aHR = 1.46 [95% CI = 1.13-1.88]), Crohn's disease (pooled aHR = 1.53 [95%CI = 1.04-2.26]), and ulcerative colitis (pooled aHR = 1.78 [95%CI = 1.15-2.75]). Conversely, any atopic manifestation by age 3 was not associated with IBD (pooled aHR = 1.20 [95%CI = 0.95-1.52]), nor were analyses specifically focused on early-life food-related allergic symptoms, asthma, and allergic rhinitis. CONCLUSION: While atopic manifestations in early childhood were overall not associated with IBD, children with atopic dermatitis specifically were at increased risk of developing IBD, suggesting shared etiologic traits; these findings might be useful in identifying at-risk individuals for IBD.

Kono-S anastomosis in Crohn's disease: initial experience in pediatric patients.

PURPOSE: Children diagnosed with Crohn's disease (CD) often undergo ileocecal resection (ICR) during childhood. Anastomotic recurrence is a frequent finding following this procedure. Data addressing the effect of the anastomosis type on disease recurrence are scarce in the pediatric population. The Kono-S anastomosis has shown promise in reducing endoscopic, clinical, and surgical recurrence rates in adults. We aimed to report our experience with Kono-S anastomosis in children, focusing on its feasibility and postoperative complications. METHODS: We retrospectively analyzed pediatric CD patients who underwent ICR with Kono-S anastomosis between August 2022 and May 2023. Data on demographics, clinical characteristics, surgery, hospitalization, and follow-up including colonoscopy were collected. Complications were classified using the Clavien-Dindo classification. RESULTS: Twelve patients (7 females, 58.3%) were included. Six (50%) of the patients had the B3 luminal form of the disease (according to Paris classification). Median surgery duration was 174 (interquartile range [IQR] 161-216) minutes. Anastomosis creation took a median of 62 (IQR, 54.5-71) minutes. Median hospitalization length was 6 (IQR 4-7) days. No short- or mid-term complications were observed. Median follow-up duration was 9.5 (IQR 6.8-12) months. CONCLUSION: According to our results, Kono-S anastomosis is safe and feasible in pediatric CD patients, with no observed postoperative complications. These findings support the potential benefit of using Kono-S anastomosis as a treatment approach in children with CD.

Sustainability of biologic treatment in paediatric patients with Crohn's disease: population-based registry analysis.

BACKGROUND: We aimed to evaluate the predictors of sustainability of biologic drugs for paediatric patients with Crohn's disease (CD). METHODS: The Czech National Prospective Registry of Biologic and Targeted Therapy of Inflammatory Bowel Disease (CREdIT) was used to identify the biologic treatment courses in paediatric patients with CD. Mixed-effects Cox models and propensity score analyses were employed to evaluate predictors of treatment sustainability. RESULTS: Among the 558 observations of 473 patients, 264 were treated with adalimumab (47%), 240 with infliximab (43%), 41 with ustekinumab (7%), and 13 with vedolizumab (2%). Multivariable analysis revealed higher discontinuation risk with infliximab compared to adalimumab (HR = 0.600, 95%CI 0.389-0.926), both overall and in first-line treatment (HR = 0.302, 95%CI 0.103-0.890). Infliximab versus adalimumab was associated with shorter time to escalation (HR = 0.094, 95%CI 0.043-0.203). Propensity-score analysis demonstrated lower sustainability of infliximab (HR = 0.563, 95%CI 1.159-2.725). The time since diagnosis to treatment initiation (HR = 0.852, 95%CI 0.781-0.926) was the most important predictor. Baseline immunosuppressive therapy prolonged sustainability with infliximab (HR = 2.899, 95%CI 1.311-6.410). CONCLUSIONS: Given the results suggesting shorter sustainability, the need for earlier intensification and thus higher drug exposure, and the greater need for immunosuppression with infliximab than with adalimumab, the choice of these drugs cannot be considered completely equitable. IMPACT: Our study identified predictors of sustainability of biologic treatment in paediatric patients with Crohn's disease, including adalimumab (versus infliximab), early initiation of biologic treatment, and normalised baseline haemoglobin levels. Infliximab treatment was associated with earlier intensification, higher drug exposure, and a greater need for immunosuppression. Parents and patients should be fully informed of the disadvantages of intravenous infliximab versus adalimumab during the decision-making process. This study emphasises the importance of not delaying the initiation of biologic therapy in paediatric patients with Crohn's disease.

Prediction of thiopurine failure in pediatric Crohn's disease: pediatric IBD Porto group of ESPGHAN.

BACKGROUND: Maintaining of remission early in the disease course of Crohn's disease (CD) is essential and has major impact on the future prognosis. This study aimed to identify baseline predictors to develop model allowing stratification of patients who will not benefit from long-term azathioprine (AZA) treatment and will require more intensive therapy. METHODS: This study was designed to develop clinical prediction rule using retrospective data analysis of pediatric CD patients included in prospective inception cohort. Clinical relapse was defined as necessity of re-induction of remission. Sequence of Cox models was fitted to predict risk of relapse. RESULTS: Out of 1190 CD patients from 13 European centers, 441 were included, 50.3% patients did not experience clinical relapse within 2 years of AZA treatment initiation. Median time to relapse was 2.11 (CI 1.59-2.46) years. Of all the tested parameters available at diagnosis, six were significant in multivariate analyses: C-reactive protein (p = 0.038), body mass index Z-score >0.8 SD (p = 0.002), abnormal sigmoid imaging (p = 0.039), abnormal esophageal endoscopy (p = 0.005), ileocolonic localization (p = 0.023), AZA dose in specific age category (p = 0.031). CONCLUSIONS: Although the possibility of predicting relapse on AZA treatment appears limited, we developed predictive model based on six baseline parameters potentially helpful in clinical decision. IMPACT: The possibility of predicting relapse on AZA treatment appears to be possible but limited. We identified six independent predictors available at diagnosis of early AZA/6-MP treatment failure in pediatric CD patients. Using combination of these factors, a model applicable to clinical practice was created. A web-based tool, allowing estimation of individual relapse risk in pediatric CD patients on a particular therapeutic regimen, has been developed.

Postvaccination Immunogenicity of BNT162b2 SARS-CoV-2 Vaccine and Its Predictors in Pediatric Inflammatory Bowel Disease.

OBJECTIVES: We prospectively compared the postvaccination immunity to messenger ribonucleic acid BNT162b2 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine of our pediatric patients over 12 years old with inflammatory bowel disease (IBD) to that of healthy controls and looked for predictors of its robustness. METHODS: Anti-receptor binding domain, anti-spike S2, and anti-nucleocapsid immunoglobin-G (IgG) and immunoglobin-A levels were measured in 139 pediatric patients with IBD [65 fully vaccinated (2 doses), median age 16.3, interquartile range (IQR) 15.2-17.8 years, median time from vaccination (IQR) 61.0 (42.0-80.0) days] and 1744 controls (46, 37-57 years) using microblot array. RESULTS: All IBD and control patients developed positive anti-receptor binding domain IgG antibodies at comparable titers. The proportion of observations with positive anti-spike S2 IgG was higher in patients with IBD than in controls [63% vs 21%, odds ratio 2.99 (1.51-5.90)], as was its titer [median (IQR) 485 (92-922) vs 79 [33-180] IU/mL]. Anti-receptor binding domain and anti-spike S2 IgG levels were associated with IBD status. We found an association between anti-spike S2 IgG levels and time since vaccination (ß -4.85, 95% CI -7.14 to 2.71, P = 0.0001), history of SARS-CoV-2 polymerase chain reaction positivity (206.76, 95% CI 39.93-374.05, P = 0.0213), and anti-tumor necrosis factor treatment (-239.68, 95% CI -396.44-83.55, P = 0.0047). Forty-three percent of patients reported vaccination side effects (mostly mild). Forty-six percent of observations with positive anti-nucleocapsid IgG had a history of SARS-CoV-2 infection. CONCLUSIONS: Patients with IBD produced higher levels of postvaccination anti-spike S2 antibodies than controls. Previous SARS-CoV-2 infection is associated with higher production of postvaccination antibodies and anti-tumor necrosis factor treatment with lower production.

Serum and Mucosal CD30 in Pediatric Inflammatory Bowel Diseases: Useful Biomarker for Diagnosis and Disease Activity Monitoring?

BACKGROUND: Inflammatory bowel diseases (IBD) frequently manifest in pediatric age, but may have atypical clinical, histological and laboratory features. Their underlying immune pathophysiology is incompletely understood, rendering quick diagnosis followed by tailored therapy difficult. The tumor necrosis factor superfamily receptor CD30 has been proposed as a potential marker of ulcerative colitis (UC) and has also been associated with elevated Th2 helper T cells. METHODS: A cohort of pediatric patients with UC and Crohn's disease (CD) was evaluated for serum soluble CD30 (sCD30) using ELISA and expression of CD30 and subpopulations of Th1/Th2/Th17 lymphocytes in the gastrointestinal mucosa using flow cytometry (FCM). The dataset is supported by endoscopic and microscopic activity of the disease and basic laboratory markers of inflammation. RESULTS: The cohort consisted of 102 observations from 94 patients. sCD30 levels did not differ between patients with CD or UC. However, sCD30 levels correlated with levels of CRP, ESR, fecal calprotectin and albumin and also with clinical activity of the disease in patients with both UC and CD. FCM was not helpful in evaluation of mucosal CD30, which was lowly expressed and not associated with the diagnosis or disease activity. We show augmented Th2 and Th1/17 response in terminal ileum and right-sided colon and decreased Th1/17 response in left-sided colon of UC patients. T lymphocyte subsets were also affected by anti-TNF treatment and patients' age. CONCLUSIONS: Neither sCD30 nor mucosal CD30 expression was helpful in differentiating between UC and CD. sCD30 seems to reflect a degree of systemic inflammation and clinical activity in IBD.

Risk factors for dermatological complications of anti-TNF therapy in a cohort of children with Crohn's disease.

Studies showing a substantial frequency of dermatologic complications in paediatric Crohn's disease (CD) patients on anti-tumour necrosis factor (TNF) therapy preferentially include patients treated with infliximab. We aimed to identify risk factors for the cumulative incidence of skin complications in a paediatric cohort receiving either adalimumab or infliximab and found an association between current skin complications and the patient's current clinical condition. This study retrospectively evaluated dermatologic complications in an inception cohort of 100 paediatric CD patients receiving the first anti-TNF (Motol PIBD cohort). Patient data were collected every 3 months. The lesions were classified as psoriatic, atopic dermatitis, or others. We used Cox regression to evaluate the association between predefined variables and the time to complication and a generalised linear mixed model to assess the association between the patient's current condition and the occurrence of complications. Among the 89 included children, 35 (39%) presented with dermatologic lesions. The only predictor associated with any complication was infliximab (versus adalimumab) therapy (hazard ratio [HR]: 2.07; 95% confidence interval [CI]: 1.03-4.17; p = 0.04). Infliximab therapy (HR: 5.5; 95%CI: 1.59-19.06; p = 0.01) and a family history of atopy (HR: 3.4; 95%CI 1.35-8.57, p = 0.002) were associated with early manifestation of atopic dermatitis. Lower C-reactive protein levels (odds ratio [OR], 0.947; 95% CI, - 0.898 to 0.998; p = 0.046) and infliximab (versus adalimumab) were associated with the occurrence of any dermatologic complications (OR, 5.93; 95% CI, 1.59-22.07; p = 0.008).Conclusion: The frequency of skin complications seems high in paediatric CD patients treated with anti-TNF and is even higher in those treated with infliximab. What is Known: •The dermatologic complications occur during treatment with anti-tumour necrosis factor. •The frequency of skin complications in paediatric patients with Crohn's disease is high. What is New: •Infliximab (vs. adalimumab) was identified as a strong risk factor for the cumulative incidence of skin complications. •Lower C-reactive protein levels were associated with the current occurrence of dermatologic complications.

The Accuracy of a Home-performed Faecal Calprotectin Test in Paediatric Patients With Inflammatory Bowel Disease.

OBJECTIVES: Owing to the invasiveness of endoscopy, the use of biomarkers, especially faecal calprotectin (FC), has become standard for remission assessment. This study aimed to compare the accuracy for detection of endoscopic activity using recently developed FC home test using smartphone application (FC-IBDoc) against standard enzyme-linked immunosorbent assay (ELISA). METHODS: In all, 102 consecutive observations (89 participants) were included in prospective observational study. FC-IBDoc was performed parallelly with FC-ELISA in paediatric patients with inflammatory bowel disease indicated for endoscopy. Both tests were performed by trained staff. Mucosal healing was defined using Simple Endoscopic Score for Crohn disease (CD) ≤2 in patients with CD (n = 44), ulcerative colitis (UC) Endoscopic Index of Severity ≤4 in patients with UC (n = 27) and Rutgeerts score i0 and i1 without colon involvement in patients with CD after ileocaecal resection (n = 19). RESULTS: Out of 102 endoscopic findings 23 were assessed as mucosal healing. We found an association of the mucosal healing scores of the entire group both with FC-ELISA (P = 0.002) and FC-IBDoc (P = 0.001). The area under the receiver operating characteristic curve for FC-ELISA was 0.883 (95% confidence interval 0.807-0.960), with optimal cut-off at 136.5 µg/g. The area under the receiver operating characteristic curve for FC-IBDoc was 0.792 (95% confidence interval 0.688-0.895) with optimal cut-off at 48 µg/g. The FC-ELISA was more accurate than FC-IBDoc when tested by a Delong test (P = 0.023). CONCLUSIONS: Standard FC-ELISA for FC evaluation is more reliable predictor of mucosal healing than the FC-IBDoc in paediatric patients with inflammatory bowel disease. The cut-off values for both tests were incongruous.

Prediction of Thiopurine Metabolite Levels Based on Haematological and Biochemical Parameters.

OBJECTIVES: Therapeutic drug monitoring of thiopurine erythrocyte levels is not available in all centers and it usually requires quite a long time to obtain the results. The aims of this study were to build a model predicting low levels of 6-thioguanine and 6-methylmercaptopurine in pediatric inflammatory bowel disease (IBD) patients and to build a model to predict nonadherence in patients treated with azathioprine (AZA). METHODS: The study consisted of 332 observations in 88 pediatric IBD patients. Low AZA dosing was defined as 6-thioguanine levels <125 pmol/8 × 10 erythrocytes and 6-methylmercaptopurine levels <5700 pmol/8 × 10 erythrocytes. Nonadherence was defined as undetectable levels of 6-thioguanine and 6-methylmercaptopurine <240 pmol/8 × 10 erythrocytes. Data were divided into training and testing part. To construct the model predicting low 6-thioguanine levels, nonadherence, and the level of 6-thioguanine, the modification of random forest method with cross-validation and resampling was used. RESULTS: The final models predicting low 6-thioguanine levels and nonadherence had area under the curve, 0.87 and 0.94; sensitivity, 0.81 and 0.82; specificity, 0.80 and 86; and distance, 0.31 and 0.21, respectively, when applied on the testing part of the dataset. When the final model for prediction of 6-thioguanine values was applied on testing dataset, a root-mean-square error of 110 was obtained. CONCLUSIONS: Using easily obtained laboratory parameters, we constructed a model with sufficient accuracy to predict patients with low 6-thioguanine levels and a model for prediction of AZA treatment nonadherence (web applications: https://hradskyo.shinyapps.io/6TG_prediction/ and https://hradskyo.shinyapps.io/Non_adherence/).

Fecal calprotectin is not a clinically useful marker for the prediction of the early nonresponse to exclusive enteral nutrition in pediatric patients with Crohn disease.

Exclusive enteral nutrition (EEN) has been recommended as the first-line therapy in children with active Crohn disease (CD). The primary aim of our study was to determine whether it is possible to use the difference between basal fecal calprotectin (F-CPT) and the value at week 2 of EEN to predict clinical response at week 6. We prospectively collected stool samples for F-CPT analysis and clinical and laboratory parameters during EEN from 38 pediatric patients (28 boys, median age 12.8 years) with newly diagnosed active luminal CD. The difference between F-CPT concentrations before EEN and at week 2 did not predict clinical non-response at week 6 (OR 0.9996 95% CI 0.9989-1.0002, p = 0.18); however, it predicted patients who did not achieve clinical remission at week 6 (OR 0.9993, 95% CI 00.9985-0.9998, p = 0.006) with sensitivity of 58%, and specificity of 92% for cut-off of F-CPT increase by 486 µg/g.Conclusions: An early decrease in F-CPT levels in children with newly diagnosed active luminal CD did not predict clinical response at week 6 of EEN induction therapy, and clinical remission was predicted with low accuracy. Therefore, F-CPT cannot be used as a predictor to select the patients in whom EEN should be terminated. What is Known: • The fecal calprotectin (F-CPT) is an important marker of intestinal inflammation. • Approximately 25% of pediatric patients with Crohn disease (CD) do not achieve clinical remission, and there is still no sufficient predictor of response to exclusive enteral nutrition (EEN) treatment. What is New: • The difference between the F-CPT concentrations before EEN treatment and at week 2 did not predict clinical response to treatment at week 6, even if it predicted clinical remission, however, with low accuracy. F-CPT is not a suitable predictor to select the patients for discontinuing of EEN induction therapy.

Correction to: Fecal calprotectin is not a clinically useful marker for the prediction of the early nonresponse to exclusive enteral nutrition in pediatric patients with Crohn disease.

This article was originally published with all author names incorrectly listed. All author names have now been transposed and appear correctly above. The original article was corrected.

Association Between Maternal Infections in Pregnancy and the Risk of Inflammatory Bowel Disease in the Offspring: Findings From Two Scandinavian Birth Cohorts.

BACKGROUND: The association of infections and antibiotic use in pregnancy and the risk of inflammatory bowel disease (IBD) development in the offspring have been scarcely investigated. We examined infection and antibiotic use in pregnancy and the risk of IBD in offspring. METHODS: We followed participants from the All Babies in Southeast Sweden (ABIS) and the Norwegian mother father and child cohort (MoBa) from birth (1997-2009) until 2020-2021. IBD diagnosis was classified as ≥2 records in national registers. Information on infections (any, gastrointestinal, and respiratory), their timing (early or late in pregnancy), and antibiotic use in pregnancy were collected from questionnaires. Cox proportional-hazard regression and meta-analytic methods were used to estimate pooled adjusted hazard ratios (aHRs) for IBD and its subtypes, adjusted for parental IBD, maternal smoking, and education. Sensitivity analyses accounted for exposure to antibiotics and infections 0-12 months of age. RESULTS: We followed 117 493 children for 2 024 299 person-years (follow-up 22.3 years in ABIS and 16.4 years in MoBa), including 451 IBD cases. The aHRs for any infection and respiratory infections in pregnancy and offspring IBD were close to one (aHR = 0.99 [95% CI = 0.73-1.33] and aHR = 1.00 [95% CI = 0.81-1.23], respectively). However, any versus no infection in early pregnancy was associated with IBD development (aHR = 1.26 [95% CI = 1.02-1.55]), particularly Crohn's disease (CD; aHR = 1.40 [95% CI = 1.01-1.93]). Any versus no gastrointestinal infection in late pregnancy was associated with offspring CD (aHR = 1.95 [95% CI = 1.34-2.84]). Antibiotic use in pregnancy was not associated with IBD in the child (aHR = 1.15 [95% CI = 0.93-1.44]). CONCLUSIONS: In this binational birth cohort study, the risk of offspring IBD varied by infection type and timing but not with maternal antibiotic use in pregnancy.

In this study, with over 117 000 participants from 2 Scandinavian birth cohorts, the type and timing of maternal infections in pregnancy were associated with the offspring's risk of inflammatory bowel disease.

Faecal Bacteriome and Metabolome Profiles Associated with Decreased Mucosal Inflammatory Activity Upon Anti-TNF Therapy in Paediatric Crohn's Disease.

BACKGROUND AND AIMS: Treatment with anti-tumour necrosis factor α antibodies [anti-TNF] changes the dysbiotic faecal bacteriome in Crohn's disease [CD]. However, it is not known whether these changes are due to decreasing mucosal inflammatory activity or whether similar bacteriome reactions might be observed in gut-healthy subjects. Therefore, we explored changes in the faecal bacteriome and metabolome upon anti-TNF administration [and therapeutic response] in children with CD and contrasted those to anti-TNF-treated children with juvenile idiopathic arthritis [JIA]. METHODS: Faecal samples collected longitudinally before and during anti-TNF therapy were analysed with regard to the bacteriome by massively parallel sequencing of the 16S rDNA [V4 region] and the faecal metabolome by 1H nuclear magnetic resonance imaging. The response to treatment by mucosal healing was assessed by the MINI index at 3 months after the treatment started. We also tested several representative gut bacterial strains for in vitro growth inhibition by infliximab. RESULTS: We analysed 530 stool samples from 121 children [CD 54, JIA 18, healthy 49]. Bacterial community composition changed on anti-TNF in CD: three members of the class Clostridia increased on anti-TNF, whereas the class Bacteroidia decreased. Among faecal metabolites, glucose and glycerol increased, whereas isoleucine and uracil decreased. Some of these changes differed by treatment response [mucosal healing] after anti-TNF. No significant changes in the bacteriome or metabolome were noted upon anti-TNF in JIA. Bacterial growth was not affected by infliximab in a disc diffusion test. CONCLUSIONS: Our findings suggest that gut mucosal healing is responsible for the bacteriome and metabolome changes observed in CD, rather than any general effect of anti-TNF.

Physical activity in childhood and later risk of inflammatory bowel disease: A Scandinavian birth cohort study.

BACKGROUND AND OBJECTIVE: Retrospective data have linked adult physical activity (PA) to reduced risk of inflammatory bowel disease (IBD). We aimed to prospectively examine the association of PA and screen time (ST) in childhood with later risk of IBD, for which data are scarce. METHODS: Using two population-based birth cohorts (All Babies in Southeast Sweden [ABIS] and Norwegian Mother, Father, and Child Cohort Study [MoBa]), we retrieved parent-reported data on PA and ST degree at ages 3 and 8 years. Data were modelled as binary (high vs. low) and numerical (hours/day) exposures. Inflammatory bowel disease was defined as ≥2 diagnostic records in national health registers. Cox regression estimated hazard ratios adjusted for potential confounding from parental IBD, country of origin, education, and smoking habits (Adjusted hazard ratio (aHR)). Our 8-year analyses included a 2-year lag period to reduce the risk of reverse causation. Cohort-specific estimates were pooled using random-effects model. RESULT: Among 65,978 participants from ABIS (n = 8810) and MoBa (n = 57,168) with available data, 266 developed IBD. At 3 years, children with high versus low PA had an aHR of 1.12 for IBD (95%CI = 0.87-1.43); high versus low ST showed an aHR of 0.91 (95%CI = 0.71-1.17). Conversely, at 8 years, high versus low ST was associated with increased risk of later IBD (aHR = 1.51; 95%CI = 1.02-2.25), but PA at 8 years, was not linked to IBD (aHR = 1.19; 95%CI = 0.80-1.76). Subtype-specific analyses for Crohn's disease and ulcerative colitis did not differ appreciably. CONCLUSION: Acknowledging possible confounding variables, children with high versus low ST at 8 years were at increased risk of IBD. In contrast, PA degree was not linked to IBD at any age category.

Adalimumab vs Infliximab in Pediatric Patients With Crohn's Disease: A Propensity Score Analysis and Predictors of Treatment Escalation.

INTRODUCTION: Two antitumor necrosis factor therapies (infliximab [IFX] and adalimumab [ADA]) have been approved for the treatment of pediatric Crohn's disease (CD) but have not been compared in head-to-head trials. The aim of this study was to compare the efficacy and safety of ADA and IFX by propensity score matching in a prospective cohort of pediatric patients with luminal CD and at least a 24-month follow-up. METHODS: Among 100 patients, 75 met the inclusion criteria, and 62 were matched by propensity score. We evaluated time to treatment escalation as the primary outcome and primary nonresponse, predictors of treatment escalation and relapse, serious adverse events, pharmacokinetics, and effect of concomitant immunomodulators as secondary outcomes. RESULTS: There was no difference between ADA and IFX in time to treatment escalation (HR = 0.63 [95% CI 0.31-1.28] P = 0.20), primary nonresponse (P = 0.95), or serious adverse events. The median (interquartile range) trough levels at the primary outcome were 14.05 (10.88-15.40) and 6.15 (2.08-6.58) µg/mL in the ADA and IFX groups, respectively. On a multivariate analysis, the combination of anti-Saccharomyces cerevisiae antibody negativity and antineutrophil cytoplasmic antibody positivity was a strong independent predictor of treatment escalation (HR 5.19, [95% CI 2.41-11.18], P < 0.0001). The simple endoscopic score for CD, L3 disease phenotype, and use of concomitant immunomodulators for at least the first 6 months revealed a trend toward significance on a univariate analysis. DISCUSSION: Propensity score matching did not reveal substantial differences in efficacy or safety between ADA and IFX. The anti-S. cerevisiae antibody negativity and antineutrophil cytoplasmic antibody positivity combination is a strong predictor of treatment escalation.

Predictive value of tissue calprotectin for disease recurrence after ileocecal resection in pediatric Crohn's disease.

AIM: Detection of possible predictive factors of endoscopic recurrence after ileocecal resection in Crohn's disease could be very beneficial for the individual adjustment of postoperative therapy. The aim of this study was to verify, whether immunohistochemical detection of calprotectin in resection margins is useful in diagnostics of endoscopic recurrence. METHODS: In this study we included pediatric patients with Crohn's disease who underwent ileocecal resection, regardless of pre-operative or post-operative therapy (n=48). We collected laboratory, clinical, surgical, endoscopic and histopathological data at the time of surgery and at 6 months after surgery. The immunohistochemical staining of calprotectin antigen was performed on all paraffin blocks from the resection margins. RESULTS: Out of 48 patients 52% had endoscopic recurrence in the anastomosis (defined by Rutgeerts score) within 6 months after surgery. The number of cells positive for calprotectin in the proximal resection margin was negatively associated with recurrence (P=0.008), as was the elevated level of total calprotectin (from both resection margins). There was no correlation of calprotectin in distal resection margin and endoscopic recurrence. Fecal calprotectin over 100 ug/g (P=0.0005) and high CRP (P<0.001) at 6 months after ileocecal resection and peritonitis (P=0.048) were associated with endoscopic recurrence. CONCLUSION: Approximately half of the patients developed endoscopic recurrence within 6 months after ileocecal resection. The predictive value of tissue calprotectin is questionable, as it is negatively associated with endoscopic recurrence. There are other potentially useful predictors, such as CRP and fecal calprotectin at 6 months after resection and the presence of peritonitis.

Is It Useful to Monitor Thiopurine Metabolites in Pediatric Patients with Crohn's Disease on Combination Therapy? A Multicenter Prospective Observational Study.

BACKGROUND: The additional value of azathioprine concomitant treatment on infliximab pharmacokinetics in children is not well described yet. AIMS: In the present study, we aimed to describe the relationship between thiopurine metabolite levels, infliximab trough levels, anti-IFX antibody formation, and clinical and laboratory markers of disease activity in pediatric patients with Crohn's disease, and to assess non-adherence. METHODS: Data were collected prospectively during repeated visits from pediatric patients followed for Crohn's disease in two Czech pediatric inflammatory bowel disease centers between January 2016 and June 2017. Thiopurine metabolites (6-thioguanine and 6-methylmercaptopurine) were measured by high-performance liquid chromatography. Infliximab trough levels and anti-IFX antibody serum levels were measured routinely by ELISA. The risk of loss of response to infliximab therapy was also assessed. RESULTS: A significant association between infliximab serum levels and 6-thioguanine erythrocyte levels was observed when tested as categorical variables (63 patients, 321 observations). To predict infliximab levels > 5 µg/mL, we propose a 6-thioguanine cutoff of 278 pmol/8 × 108 erythrocytes (sensitivity, 0.799; specificity, 0.347). A higher loss-of-response-to-infliximab rate (tested in a subgroup of 51 patients) was observed in patients with undetectable 6-thioguanine levels than in those with detectable levels (p = 0.026). Non-adherence to azathioprine therapy was suspected in 20% of patients. CONCLUSION: Thiopurine metabolite monitoring in pediatric patients with Crohn's disease is useful when optimizing combination therapy. Pediatric patients with undetectable 6-thioguanine levels are more likely to lose response to infliximab therapy. When targeting optimal infliximab levels, the 6-thioguanine cutoff levels in children appear to be higher than in adults.

Vaccinations and Immunization Status in Pediatric Inflammatory Bowel Disease: A Multicenter Study From the Pediatric IBD Porto Group of the ESPGHAN.

BACKGROUND: Vaccine-preventable diseases and opportunistic infections in pediatric inflammatory bowel disease (IBD) are increasingly recognized issues. The aims of this study were to evaluate vaccinations, immunization status, and consequent therapeutic management in children with IBD and to analyze the differences among patients diagnosed before (Group 1) and after June 2012 (Group 2). METHODS: This was a multicenter, retrospective cohort investigation. Between July 2016 and July 2017, 430 children with IBD were enrolled in 13 centers. Diagnosis, therapeutic history, vaccinations, and immunization status screening at diagnosis and at immunosuppressant (IM)/biologic initiation and reasons for incomplete immunization were retrieved. RESULTS: Vaccination rates at diagnosis were unsatisfactory for measles, mumps, and rubella (89.3%), Haemophilus influenzae (81.9%), meningococcus C (23.5%), chickenpox (18.4%), pneumococcus (18.6%), papillomavirus (5.9%), and rotavirus (1.9%). Complete immunization was recorded in 38/430 (8.8%) children, but specific vaccines were recommended in 79/430 patients (18.6%), without differences between the 2 groups. At IM start, 22% of children were tested for Epstein-Barr virus (EBV) status, with 96.2% of EBV-naïve patients starting azathioprine, without differences between Groups 1 and 2. Screening for latent tuberculosis (TB) before start of biologics was performed in 175/190 (92.1%), with up to 9 different screening strategies and numerous inconsistencies. CONCLUSIONS: We demonstrated a poor immunization status at diagnosis in children with IBD, which was not followed by proper vaccination catch-up. EBV status before IM initiation and latent TB before biologics were not adequately assessed. Thus, the overall impact of the current guidelines seems unsatisfactory.

Limited clinical significance of tissue calprotectin levels in bowel mucosa for the prediction of complicated course of the disease in children with ulcerative colitis.

BACKGROUND: Fecal calprotectin (F-CPT) represents one of the most widely used biomarkers for intestinal inflammation. However, the levels may be false negative or false positive in some situations. AIMS: To evaluate the usefulness of immunohistochemical (IHC) detection of tissue calprotectin (T-CPT) in bowel mucosa in children with ulcerative colitis (UC). We focused at correlation of T-CPT with levels of F-CPT and endoscopic and microscopic disease activity at the time of diagnosis and tested whether T-CPT could serve as predictor of complicated course of the disease. METHODS: Forty-nine children with newly diagnosed UC between 6/2010-1/2018 entered the study. Endoscopic activity was objectified using the Ulcerative Colitis Endoscopic Index of Severity (UCEIS), clinical activity by Pediatric Ulcerative Colitis Activity Index (PUCAI) and microscopic activity by Geboes and Nancy score. The IHC staining for CPT antigen was performed on bioptic samples from 6 bowel segments and the number of CPT + cells were counted per 1HPF. During the minimal follow-up of 12 months we searched for presence of complications. As outcome for Cox regression model we used composite endpoints: A) Acute Severe Colitis, colectomy, anti-TNF treatment; B) systemic corticotherapy; C) systemic 5-aminosalicylic acid therapy. RESULTS: Neither levels of T-CPT nor values of UCEIS, Geboes or Nancy score predicted the given complications. We found F-CPT levels (HR 2.42 and 2.52) and PUCAI > 40 points (HR 2.98) as predictors of time to endpoints B and C. Good correlation was found between T-CPT levels and Geboes score (k = 0.65) and Nancy score (k = 0.62) and modest with F-CPT (k = 0.44), UCEIS (k = 0.38) and PUCAI (k = 0.42). CONCLUSIONS: T-CPT correlated well with microscopic scores. F-CPT and PUCAI appear to be better predictors of unfavorable outcome in patients with UC.