Colonic malakoplakia in a pediatric renal transplant recipient case report

Malakoplakia is a rare, chronic granulomatous disease that mainly affects the genitourinary system of immunocompromised adults. It is caused by a bactericidal deficit in macrophages and, therefore, the treatment includes antimicrobials that reach high concentrations in macrophages. To our knowledge, we present the first case of malakoplakia in a pediatric solid organ transplant recipient. Our patient is a 15-year-old male renal transplant recipient who presented with recurrent diarrhea. Blood, urine, and gastrointestinal pathogen panel testing were positive for enteroaggregative Escherichia coli. A colonoscopy revealed diffuse malakoplakia. He had a complete resolution of symptoms with trimethoprim-sulfamethoxazole therapy. Unfortunately, his malakoplakia recurred after 9 months prompting the transition of therapy to oral gentamicin with subsequent remission. Malakoplakia should be considered in the differential of solid organ transplant recipients with recurrent gastrointestinal infections.

NOD2 Polymorphisms May Direct a Crohn Disease Phenotype in Patients With Very Early-Onset Inflammatory Bowel Disease

NOD2/CARD15 was the first susceptibility gene recognized for adult-onset Crohn's (or Crohn) disease (CD). Recessive inheritance of NOD2 polymorphisms has been implicated as a mechanistic driver of pediatric-onset CD. In patients with very early-onset inflammatory bowel disease (VEO-IBD), however, the clinical relevance of NOD2 polymorphisms has not been fully established. Ten VEO-IBD patients with NOD2 polymorphisms ( NOD2 +) were compared to 16 VEO-IBD patients without genetic variants in NOD2 or any other VEO-IBD susceptibility genes ( NOD2 -). The majority of NOD2 + patients exhibited a CD-like phenotype (90%), linear growth impairment (90%), and arthropathy (60%), all of which were significantly more common than in the NOD2 - group ( P = 0.037, P = 0.004, P = 0.026, respectively). We propose that the presence of NOD2 polymorphisms in patients with VEO-IBD might confer a CD-like phenotype, linear growth impairment, and arthropathy. These findings should be validated in larger cohorts and may guide precision medicine for patients with VEO-IBD in the future.

Exome Sequencing Implicates DGKZ , ESRRA , and GXYLT1 for Modulating Granuloma Formation in Crohn Disease

Non-caseating granulomas may indicate a more aggressive phenotype of Crohn disease (CD). Genetic associations of granulomatous CD (GCD) may help elucidate disease pathogenesis. Whole-exome sequencing was performed on peripheral blood-derived DNA from 17 pediatric patients with GCD and 19 with non-GCD (NGCD), and from an independent validation cohort of 44 GCD and 19 NGCD cases. PLINK (a tool set for whole-genome association and population-based linkage analyses) analysis was used to identify single nucleotide polymorphisms (SNPs) differentiating between groups, and subgroup allele frequencies were also compared to a public genomic database (gnomAD). The Combined Annotation Dependent Depletion scoring tool was used to predict deleteriousness of SNPs. Human leukocyte antigen (HLA) haplotype findings were compared to a control group (n = 8496). PLINK-based analysis between GCD and NGCD groups did not find consistently significant hits. gnomAD control comparisons, however, showed consistent subgroup associations with DGKZ , ESRRA , and GXYLT1 , genes that have been implicated in mammalian granulomatous inflammation. Our findings may guide future research and precision medicine.

Donor-recipient specificity and age-dependency in fecal microbiota therapy and probiotic resolution of gastrointestinal symptoms

Fecal microbiota transplantation (FMT) has proven to be an effective treatment for recurrent Clostridioides difficile infection (rCDI) in both adult and pediatric patients. However, as microbiome development is a critical factor in children, it remains unclear whether adult fecal donors can provide age-appropriate functional restoration in pediatric patients. To address this issue, we conducted an integrated systems approach and found that concordant donor strain engraftment, along with metabolite restoration, are associated with FMT outcomes in both adult and pediatric rCDI patients. Although functional restoration after FMT is not strain-specific, specialized metabolic functions are retained in pediatric patients when adult fecal donors are used. Furthermore, we demonstrated broad utility of high-resolution variant-calling by linking probiotic-strain engraftment with improved gastrointestinal symptoms in adults with irritable bowel syndrome and in children with autism spectrum disorder. Our findings emphasize the importance of strain-level identification when assessing the efficacy of probiotics and microbiota-based therapeutics.

Food for Thought: Remission of Perianal Pediatric Crohn's Disease on Specific Carbohydrate Diet Monotherapy

There is growing interest among patients about the specific carbohydrate diet (SCD) as a treatment for Crohn's disease. In the meantime, deep remission in patients using SCD as their sole treatment has not been documented. We report a case with perianal and ileocolonic Crohn's disease in whom SCD monotherapy successfully induced and maintained not only clinical, but also endoscopic, radiographic and histologic (ie, deep mucosal remission) remission as well.

Esophageal Lesion Reveals an Aortic Pseudoaneurysm in the Setting of Actinomyces odontolyticus Bacteremia

A toddler presented with hematemesis a few weeks after ingesting a penny. Workup revealed an esophageal lesion communicating with an aortic pseudoaneurysm in the setting of Actinomyces odontolyticus bacteremia. A. odontolytica is an oropharyngeal bacteria known to cause fistulas when introduced into tissue planes. (Level of Difficulty: Intermediate.).

Fecal Microbiota Transplantation for Clostridioides difficile Infection in Immunocompromised Pediatric Patients

OBJECTIVES

We sought to evaluate the safety and effectiveness of fecal microbiota transplantation (FMT) for recurrent Clostridioides difficile infection (CDI) in pediatric immunocompromised (IC) patients.

METHODS

This is a multicenter retrospective cohort study of pediatric participants who underwent FMT between March 2013 and April 2020 with 12-week follow-up. Pediatric patients were included if they met the definition of IC and were treated with FMT for an indication of recurrent CDI. We excluded patients over 18 years of age, those with incomplete records, insufficient follow-up, or not meeting study definition of IC. We also excluded those treated for Clostridioides difficile recurrence without meeting the study definition and those with inflammatory bowel disease without another immunocompromising condition.

RESULTS

Of 59 pediatric patients identified at 9 centers, there were 42 who met inclusion and no exclusion criteria. Included patients had a median age of 6.7 years. Etiology of IC included: solid organ transplantation (18, 43%), malignancy (12, 28%), primary immunodeficiency (10, 24%), or other chronic conditions (2, 5%). Success rate was 79% after first FMT and 86% after 1 or more FMT. There were no statistically significant differences in patient characteristics or procedural components when patients with a failed FMT were compared to those with a successful FMT. There were 15 total serious adverse events (SAEs) in 13 out of 42 (31%) patients that occurred during the follow-up period; 4 (9.5%) of which were likely treatment-related. There were no deaths or infections with multidrug resistant organisms during follow-up and all patients with a SAE fully recovered.

CONCLUSIONS

The success rate of FMT for recurrent CDI in this pediatric IC cohort is high and mirrors data for IC adults and immunocompetent children. FMT-related SAEs do occur (9.5%) and highlight the need for careful consideration of risk and benefit.

A Single-Center Study of Long-Term Effectiveness of Vedolizumab in Anti-TNF Refractory Pediatric Inflammatory Bowel Disease

Vedolizumab is an anti-α4β7 integrin antibody that has been used successfully in the treatment of adult-onset inflammatory bowel diseases (IBDs: Crohn disease [CD] and ulcerative colitis [UC]). Its off-label use in the pediatric IBD (PIBD) population is increasing, but knowledge on durability beyond 6 months of treatment is limited.

Methods

A real-life, single-center, retrospective study of PIBD patients treated with vedolizumab was performed. Data on demographics, prior and concomitant treatments, and disease activity were obtained at 14 weeks, 26 weeks, 1 year, and 2 years of therapy. Primary outcome was corticosteroid- and other biologic-free remission (based on pediatric ulcerative colitis activity index [PUCAI]).

Results

Thirty-nine patients were studied. By 1 year, 65% of CD and 68% of UC patients continued on vedolizumab therapy. Corticosteroid- and other biologic-free remission was 29% in CD and 16% in UC. By 2 years, 36% of CD and 47% of UC patients continued therapy. Corticosteroid- and other biologic-free remission was 21% in CD and 40% in UC. By 2 years, 80% of CD and 100% of UC patients were on intensified treatment regimen compared to the manufacturer guidance. Nine patients (23%) required surgical intervention within 26 months of starting vedolizumab indicating the severity of IBD in this cohort.

Conclusions

Vedolizumab is a useful therapeutic modality in PIBD patients refractory to anti-TNF therapy, although with declining effectiveness by 2 years. Intensified treatment regimens are associated with long-term durability. Larger prospective trials in children are warranted.

Increased number of children in households may protect against inflammatory bowel disease

BACKGROUND

The increasing incidence of inflammatory bowel disease (IBD: Crohn's disease and ulcerative colitis) around the world has coincided with a wide array of environmental and epidemiologic changes. The relationship between IBD incidence and household or family size decline, however, has not been examined before. Our background epidemiological analyses suggested an inverse association between household size and IBD incidence. We aimed to examine this further in a murine model.

METHODS

We designed a unique two-generation cohousing model of family size and IBD susceptibility in C57BL/6J mice. Serial fecal microbiomes during cohousing were examined by high-throughput 16S rRNA sequencing. After cohousing for 10 days, mice were exposed to dextran sulfate sodium (DSS) to induce acute colitis. Body weight as a significant correlate of colitis severity was measured.

RESULTS

Mice in a large household arrangement demonstrated less weight loss than mice in the small household arrangement in the DSS model. Age- and housing-dependent microbiome shifts were found.

CONCLUSIONS

Larger households may be protective against intestinal inflammation through intergenerational microbiome modulation. Our observations may set the foundation for age-dependent, microbiome-directed future prevention against IBD.

IMPACT

Epidemiological analyses in this study suggested that IBD incidence may inversely correlate with household size (an indicator of family size/children per family), which has not been examined before. A uniquely designed two-generation cohousing model of family size and IBD susceptibility in mice supported our epidemiologic observations. Microbiome changes in our cohousing model may set the foundation for age-dependent, microbiome-directed prevention against IBD.

Disturbed Pediatric Gut Microbiome Maturation in the Developmental Origins of Subsequent Chronic Disease

The microbiome is known to play an important role in the development and maintenance of human health. During early childhood the gut microbiome undergoes a rapid evolution, making this developmental window most susceptible to microbial manipulation and, therefore, most vulnerable to environmental stimuli. Such stimuli may induce persistent alterations (or dysbiosis) in microbiome and/or host physiology, thereby resulting in susceptibility to subsequent disease development. This phenomenon is frequently described as "the microbial developmental origins of disease." In this topic of the month, we call attention to the microbial developmental origins of disease by examining the potential for childhood antibiotic exposures and appendectomy (ie, inducers of dysbiosis) to influence the pathogenesis of certain multifactorial, common diseases (eg, celiac disease, inflammatory bowel disease, obesity), especially those with increasing incidence worldwide. We conclude that fully appreciating the critical components in the microbial developmental origins of common chronic disorders is a major task ahead of pediatric gastroenterologists in the 21st century. Such information will be key in working to prevent numerous common and emerging disorders.

Mucosal microbiome is predictive of pediatric Crohn's disease across geographic regions in North America

Background: Patients with Crohn's disease (CD) have an altered intestinal microbiome, which may facilitate novel diagnostic testing. However, accuracy of microbiome classification models across geographic regions may be limited. Therefore, we sought to examine geographic variation in the microbiome of patients with CD from North America and test the performance of a machine learning classification model across geographic regions. Methods: The RISK cohort included 447 pediatric patients with CD and 221 non-inflammatory bowel disease controls from across North America. Terminal ileum, rectal and fecal samples were obtained prior to treatment for microbiome analysis. We divided study sites into 3 geographic regions to examine regional microbiome differences. We trained and tested the performance of a machine learning classification model across these regions. Results: No differences were seen in the mucosal microbiome of patients with CD across regions or in either the fecal or mucosal microbiomes of controls. Machine learning classification algorithms for patients with CD performed well across regions (area under the receiver operating characteristic curve [AUROC] range of 0.85-0.91) with the best results from terminal ileum. Conclusions: This study demonstrated the feasibility of microbiome based diagnostic testing in pediatric patients with CD within North America, independently from regional influences.

Clostridioides difficile Infection in Hospitalized Pediatric Patients: Comparisons of Epidemiology, Testing, and Treatment from 2013 to 2019

OBJECTIVES

To compare the incidence, epidemiology, testing patterns, treatment, and outcomes of Clostridioides difficile infection (CDI) among hospitalized pediatric patients from 2013 to 2019.

STUDY DESIGN

The Pediatric Health Information System database was queried for patient admissions (age 0-17 years) with International Classification of Diseases, 9th and 10th edition, codes for diagnoses of CDI with a billing code for a CDI-related antibiotic treatment.

RESULTS

We identified 17 142 pediatric patients, representing 23 052 admissions, with CDI. The adjusted annual CDI incidence decreased over the study period from 7.09 cases per 10 000 patient-days (95% CI, 6.15-8.18) in 2013 to 4.89 cases per 10 000 patient-days (95% CI, 4.03-5.93) in 2019 (P < .001). C difficile-specific testing also decreased during the study period (P < .001). Chronic gastrointestinal conditions (36%) and malignancy (32%) were the most common comorbidities in CDI encounters. Oral metronidazole use decreased during the study period (P < .01) and oral vancomycin use increased (P < .001).

CONCLUSIONS

Our study demonstrates a decrease in CDI incidence in hospitalized pediatric patients, a notable change from prior studies, although this may have been influenced by altered testing patterns. We found a high incidence of CDI in patients with cancer and gastrointestinal conditions: groups that warrant targeted evaluation of CDI prevention and treatment.

Racial and Ethnic Variation in Presentation, Diagnosis, Treatment, and Outcome of Pediatric Crohn Disease: A Single Center Study

OBJECTIVES

Disparities in health care for racial/ethnic minority children in the United States who are burdened by pediatric Crohn's disease (PCD) are not well understood.

METHODS

A retrospective review of the Texas Children's Hospital ImproveCareNow database from 2007 to 2015 was performed. CD patients with a minimum of 2-year follow-up were included if the onset of symptoms attributable to inflammatory bowel disease was clearly documented. We primarily aimed to identify race and ethnicity associations in diagnostic delay, presentation, treatment, and 2-year outcomes. We also examined early versus late diagnosis (ie, over 6 months from disease onset) associations with these variables unrelated to race/ethnicity.

RESULTS

One hundred and sixty-six PCD patients [57.8% non-Hispanic White (NH-White), 18.1% African American (AA), and 15.7% Hispanic] met selection criteria. Time to diagnosis was shorter in Hispanic patients ( P < 0.01) and they were older at diagnosis than NH-White patients ( P = 0.0164). AA patients (33%, P < 0.01) and Hispanic patients (35%, P < 0.05) had lower rates of granuloma detection than NH-White patients (63%). AA patients had lower rates of steroid-free remission (SFR) at 2 years than NH-White patients ( P < 0.05). Higher ESR and lower hemoglobin levels were associated with early diagnosis ( P < 0.01). Early diagnosis was associated with higher rates of surgery within 2 years of diagnosis ( P < 0.05). Diagnostic fecal calprotectin levels inversely associated with SFR at 2 years ( P < 0.05). Early use of biologics positively, and early use of corticosteroids negatively correlated with 2-year SFR ( P < 0.05).

CONCLUSIONS

Race and ethnicity may influence the diagnosis, treatment, and outcomes of PCD. This recognition presents a nidus toward establishing equity in PCD care.

Infliximab Can Be Effective in Pediatric Patients with Ulcerative Colitis and Primary Failure of Adalimumab

OBJECTIVE

The FDA approved adalimumab, an anti-tumor necrosis factor alpha agent, for the treatment of moderate to severe pediatric ulcerative colitis (UC) in February 2021. There are no real-world publications, however, on adalimumab as the first-line biologic in pediatric UC, a form of chronic inflammatory bowel disease (IBD).

METHODS

A retrospective review was conducted to characterize the clinical courses of nine patients with moderate to severe pediatric UC who received adalimumab as their first biologic and had documented drug monitoring trough levels.

RESULTS

Seven of the nine patients, or 78%, were switched from adalimumab to another therapy due to continued symptoms or steroid-dependence at an average of 5 months from initiation. Six of these seven patients, or 86%, had adalimumab drug trough levels in the consensus therapeutic range. Three patients were successfully switched to infliximab.

CONCLUSIONS

Both the Crohn's disease-based dosing and the new FDA-approved pediatric UC dosing of adalimumab were ineffective in inducing remission in the majority of patients in our case series. This study indicates that further real-world observations are needed to optimize and position adalimumab in the treatment paradigm of moderate to severe pediatric UC.

Efficacy and Outcomes of Faecal Microbiota Transplantation for Recurrent Clostridioides difficile Infection in Children with Inflammatory Bowel Disease

BACKGROUND

Children with inflammatory bowel disease [IBD] are disproportionally affected by recurrent Clostridioides difficile infection [rCDI]. Although faecal microbiota transplantation [FMT] has been used with good efficacy in adults with IBD, little is known about outcomes associated with FMT in paediatric IBD.

METHODS

We performed a retrospective review of FMT at 20 paediatric centres in the USA from March 2012 to March 2020. Children with and without IBD were compared with determined differences in the efficacy of FMT for rCDI. In addition, children with IBD with and without a successful outcome were compared with determined predictors of success. Safety data and IBD-specific outcomes were obtained.

RESULTS

A total of 396 paediatric patients, including 148 with IBD, were included. Children with IBD were no less likely to have a successful first FMT then the non-IBD affected cohort [76% vs 81%, p = 0.17]. Among children with IBD, patients were more likely to have a successful FMT if they received FMT with fresh stool [p = 0.03], were without diarrhoea prior to FMT [p = 0.03], or had a shorter time from rCDI diagnosis until FMT [p = 0.04]. Children with a failed FMT were more likely to have clinically active IBD post-FMT [p = 0.002] and 19 [13%] patients had an IBD-related hospitalisation in the 3-month follow-up.

CONCLUSIONS

Based on the findings from this large US multicentre cohort, the efficacy of FMT for the treatment of rCDI did not differ in children with IBD. Failed FMT among children with IBD was possibly related to the presence of clinically active IBD.

Sirolimus (Rapamycin) Induced Mucosal Healing in Anti-Tumor Necrosis Factor Refractory Pediatric Ulcerative Colitis

Sirolimus (rapamycin) has been sparsely reported in the treatment of pediatric ulcerative colitis (PUC). Mucosal healing has not been examined in responders to the drug. We describe a case of infliximab refractory PUC where rapamycin induced sustained clinical remission along with mucosal healing. We conclude that rapamycin should be positioned into the expanding treatment repertoire of PUC.

Methylation quantitative trait loci are largely consistent across disease states in Crohn’s disease

Recently, we identified 1,189 CpG sites whose DNA methylation level in blood associated with Crohn’s disease. Here, we examined associations between DNA methylation and genetic variants to identify methylation quantitative trait loci across disease states in (1) 402 blood samples from 164 newly diagnosed pediatric Crohn’s disease patients taken at 2 time points (diagnosis and follow-up), and 74 non-inflammatory bowel disease controls, (2) 780 blood samples from a non-Crohn’s disease adult population, and (3) 40 ileal biopsies (17 Crohn’s disease cases and 23 non-inflammatory bowel disease controls) from group (1). Genome-wide DNAm profiling and genotyping were performed using the Illumina MethylationEPIC and Illumina Multi-Ethnic arrays. SNP-CpG associations were identified via linear models adjusted for age, sex, disease status, disease subtype, estimated cell proportions, and genotype-based principal components. In total, we observed 535,448 SNP-CpG associations between 287,881 SNPs and 12,843 CpG sites (P &lt; 8.21 × 10−14). Associations were highly consistent across different ages, races, disease states, and tissue types, suggesting that the majority of these methylation quantitative trait loci participate in common gene regulation. However, genes near CpGs associated with inflammatory bowel disease SNPs were enriched for 18 KEGG pathways relevant to inflammatory bowel disease-linked immune function and inflammatory responses. We observed suggestive evidence for a small number of tissue-specific associations and disease-specific associations in ileum, though larger studies will be needed to confirm these results. Our study concludes that the vast majority of blood-derived methylation quantitative trait loci are common across individuals, though a subset may be involved in processes related to Crohn’s disease. Independent cohort studies will be required to validate these findings.

Fecal Microbiota Transplantation Commonly Failed in Children With Co-Morbidities

OBJECTIVES

Fecal microbiota transplantation (FMT) is arguably the most effective treatment for recurrent Clostridioides difficile infection (rCDI). Clinical reports on pediatric FMT have not systematically evaluated microbiome restoration in patients with co-morbidities. Here, we determined whether FMT recipient age and underlying co-morbidity influenced clinical outcomes and microbiome restoration when treated from shared fecal donor sources.

METHODS

Eighteen rCDI patients participating in a single-center, open-label prospective cohort study received fecal preparation from a self-designated (single case) or two universal donors. Twelve age-matched healthy children and four pediatric ulcerative colitis (UC) cases from an independent serial FMT trial, but with a shared fecal donor were examined as controls for microbiome restoration using 16S rRNA gene sequencing of longitudinal fecal specimens.

RESULTS

FMT was significantly more effective in rCDI recipients without underlying chronic co-morbidities where fecal microbiome composition in post-transplant responders was restored to levels of healthy children. Microbiome reconstitution was not associated with symptomatic resolution in some rCDI patients who had co-morbidities. Significant elevation in Bacteroidaceae, Bifidobacteriaceae, Lachnospiraceae, Ruminococcaceae, and Erysipelotrichaceae was consistently observed in pediatric rCDI responders, while Enterobacteriaceae decreased, correlating with augmented complex carbohydrate degradation capacity.

CONCLUSION

Recipient background disease was a significant risk factor influencing FMT outcomes. Special attention should be taken when considering FMT for pediatric rCDI patients with underlying co-morbidities.

National Trends in Hospitalization, Surgical Resection, and Comorbidities in Pediatric Inflammatory Bowel Disease in the United States, 2002-2015

BACKGROUND AND OBJECTIVE

Therapeutic options for pediatric inflammatory bowel disease (PIBD) have dramatically changed over the last 20 years. However, the impact of modern medical management on PIBD outcomes remains unclear. We aimed to fill this gap in the literature by using a large, validated, national database, to study the change in hospitalization rates, surgical rates, and postoperative complications in PIBD over the last decade.

METHODS

The National Inpatient Sample (NIS) Database and ICD-9-CM codes were utilized to identify inpatient admissions with a primary or secondary diagnosis of pediatric Crohn's disease (CD) or ulcerative colitis (UC) from 2002-2015. Trends in hospitalizations, comorbidities (including malnutrition and weight loss), surgical procedures, and postoperative complications were examined using joinpoint regression analysis, a statistical modeling approach to evaluate the extent to which the rate of a condition changes over time.

RESULTS

There were 119,282 admissions for PIBD during the study period. The annual incidence of hospitalization increased significantly over time for both CD (average annual percent change [AAPC] 6.0%) and UC (AAPC 7.2%). The rate of intestinal resection decreased in CD patients (AAPC -6.4%) while postoperative complications remained unchanged. However, comorbidities increased significantly in CD patients (AAPC 6.8%). For pediatric UC patients, postoperative complications (AAPC 6.7%), and comorbidities (AAPC 10.2%) increased significantly over time while intestinal resection rates remained stable. Intestinal resection rate in pediatric CD has decreased over time, but not in pediatric UC.

CONCLUSION AND GLOBAL HEALTH IMPLICATIONS

Annual incidence of hospitalization and comorbidities continue to increase in PIBD. Intestinal resection rate in pediatric CD has decreased over time, but not in pediatric UC. Our findings emphasize the critical need for prevention and novel therapeutic options for this vulnerable patient population.

Pediatric Fecal Microbiota Transplantation in Recurrent Clostridioides Difficile

With the rising rates of Clostridioides (Clostridium) difficile infection (CDI) in children, recognizing the limitations of CDI-directed antibiotic therapy, especially in recurrent CDI (rCDI), is important. Fecal microbiota transplantation (FMT), which directly targets the underlying gut dysbiosis present in rCDI, is an important treatment option to consider in rCDI. This article will summarize indications, procedures, effectiveness, and the safety of FMT for rCDI in pediatric patients. [Pediatr Ann. 2021;50(12):e515-e521.].

Maternal Lactobacillus reuteri supplementation shifts the intestinal microbiome in mice and provides protection from experimental colitis in female offspring

The purpose of our experiment was to explore how stochastic (inter‐individual variation) gut microbiome composition may link to inflammatory bowel disease (IBD) susceptibility and guide the development of a perinatal preventative probiotic. Dextran sodium sulfate (DSS) was introduced to C57BL/BJ mice to induce acute colitis as a model of IBD. Potentially protective bacteria were identified using a discovery‐validation cohort approach toward stochastic DSS susceptibility. Lactobacilli (two different cocktails of L. reuteri and L. johnsonii strains) or control media were supplemented by mouth to dams prior to delivery and during lactation (i.e., perinatal probiotic). The pups were evaluated for DSS susceptibility at young adulthood. Fecal Lactobacillus was increased in the DSS‐resistant mice in both the discovery and validation cohorts. Maternal supplementation of female offspring with an L. reuteri cocktail (strains 6798‐1, 6798‐jm, and 6798‐cm) induced progressive microbiome separation and protection against colitis by young adulthood. Maternal supplementation of L. reuteri could confer protection against DSS colitis in young adult female mice. This work is the first to exploit stochastic mammalian microbiome variation to guide microbial therapeutic identification. Our findings underscore neonatal microbiome plasticity and set the stage for the potential development of perinatally deliverable protective probiotics against human IBD.

SULT1A1 and SULT1A2 Associated Extensive Prolapse-Type Inflammatory Polyposis in Crohn's Colitis

Mucosal prolapse syndrome most commonly involves the rectum and presents as solitary rectal ulcer syndrome and proctitis cystica profunda. Symptoms and endoscopic appearances are nonspecific. Histologically, mucosal prolapse is characterized by fibromuscular obliteration of the lamina propria, and displacement of crypts into submucosa and muscularis mucosae. Mucosal prolapse presenting as polyposis is rare and has only been reported involving the rectosigmoid colon. In this report, we describe a case of mucosal prolapse syndrome presenting as diffuse polyposis and colitis cystica profunda involving the hepatic, splenic flexures and descending colon in a teenage boy suffering from refractory fibrostenosing Crohn's disease. This patient was found to have possibly deleterious homozygous single nucleotide polymorphisms in both SULT1A1 and SULT1A2 genes within a unique polygenic variation of altered cell adhesion.

IFIH1 loss-of-function variants contribute to very early-onset inflammatory bowel disease

Genetic defects of innate immunity impairing intestinal bacterial sensing are linked to the development of Inflammatory Bowel Disease (IBD). Although much evidence supports a role of the intestinal virome in gut homeostasis, most studies focus on intestinal viral composition rather than on host intestinal viral sensitivity. To demonstrate the association between the development of Very Early Onset IBD (VEOIBD) and variants in the IFIH1 gene which encodes MDA5, a key cytosolic sensor for viral nucleic acids. Whole exome sequencing (WES) was performed in two independent cohorts of children with VEOIBD enrolled in Italy (n = 18) and USA (n = 24). Luciferase reporter assays were employed to assess MDA5 activity. An enrichment analysis was performed on IFIH1 comparing 42 VEOIBD probands with 1527 unrelated individuals without gastrointestinal or immunological issues. We identified rare, likely loss-of-function (LoF), IFIH1 variants in eight patients with VEOIBD from a combined cohort of 42 children. One subject, carrying a homozygous truncating variant resulting in complete LoF, experienced neonatal-onset, pan-gastrointestinal, IBD-like enteropathy plus multiple infectious episodes. The remaining seven subjects, affected by VEOIBD without immunodeficiency, were carriers of one LoF variant in IFIH1. Among these, two patients also carried a second hypomorphic variant, with partial function apparent when MDA5 was weakly stimulated. Furthermore, IFIH1 variants were significantly enriched in children with VEOIBD as compared to controls (p = 0.007). Complete and partial MDA5 deficiency is associated with VEOIBD with variable penetrance and expressivity, suggesting a role for impaired intestinal viral sensing in IBD pathogenesis.

Natural unblinding of BCG vaccination trials

There is significant public and clinical interest in the potential for Bacillus Calmette-Guérin (BCG) vaccination to protect against type 2 Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) induced COVID-19. This question could be best answered by blinded and placebo controlled clinical trials. However, a skin reaction occurs within days at the site of BCG injection, making it rather challenging to blind this vaccination. Here, we examined registered clinical trials in ClinicalTrials.gov on BCG against COVID-19 by October 9th 2020, and found that 94.7% of such trials were listed as placebo controlled (all with normal saline as placebo), and single to quadruple blinded. The mode of overcoming the natural unblinding by the BCG induced skin reaction was not clarified on the website in either of the trials. We conclude that detailed description of the strategy towards overcoming the BCG vaccination induced skin reaction associated unblinding hurdle will be important for the interpretation of the theoretically blinded COVID-19 directed clinical trials.

Whole-genome sequencing of African Americans implicates differential genetic architecture in inflammatory bowel disease

Whether or not populations diverge with respect to the genetic contribution to risk of specific complex diseases is relevant to understanding the evolution of susceptibility and origins of health disparities. Here, we describe a large-scale whole-genome sequencing study of inflammatory bowel disease encompassing 1,774 affected individuals and 1,644 healthy control Americans with African ancestry (African Americans). Although no new loci for inflammatory bowel disease are discovered at genome-wide significance levels, we identify numerous instances of differential effect sizes in combination with divergent allele frequencies. For example, the major effect at PTGER4 fine maps to a single credible interval of 22 SNPs corresponding to one of four independent associations at the locus in European ancestry individuals but with an elevated odds ratio for Crohn disease in African Americans. A rare variant aggregate analysis implicates Ca²⁺-binding neuro-immunomodulator CALB2 in ulcerative colitis. Highly significant overall overlap of common variant risk for inflammatory bowel disease susceptibility between individuals with African and European ancestries was observed, with 41 of 241 previously known lead variants replicated and overall correlations in effect sizes of 0.68 for combined inflammatory bowel disease. Nevertheless, subtle differences influence the performance of polygenic risk scores, and we show that ancestry-appropriate weights significantly improve polygenic prediction in the highest percentiles of risk. The median amount of variance explained per locus remains the same in African and European cohorts, providing evidence for compensation of effect sizes as allele frequencies diverge, as expected under a highly polygenic model of disease.

Association of Baseline Luminal Narrowing With Ileal Microbial Shifts and Gene Expression Programs and Subsequent Transmural Healing in Pediatric Crohn Disease

BACKGROUND

Transmural healing (TH) is associated with better long-term outcomes in Crohn disease (CD), whereas pretreatment ileal gene signatures encoding myeloid inflammatory responses and extracellular matrix production are associated with stricturing. We aimed to develop a predictive model for ileal TH and to identify ileal genes and microbes associated with baseline luminal narrowing (LN), a precursor to strictures.

MATERIALS AND METHODS

Baseline small bowel imaging obtained in the RISK pediatric CD cohort study was graded for LN. Ileal gene expression was determined by RNASeq, and the ileal microbial community composition was characterized using 16S rRNA amplicon sequencing. Clinical, demographic, radiologic, and genomic variables were tested for association with baseline LN and future TH.

RESULTS

After controlling for ileal location, baseline ileal LN (odds ratio [OR], 0.3; 95% confidence interval [CI], 0.1-0.8), increasing serum albumin (OR, 4; 95% CI, 1.3-12.3), and anti-Saccharomyces cerevisiae antibodies IgG serology (OR, 0.97; 95% CI, 0.95-1) were associated with subsequent TH. A multivariable regression model including these factors had excellent discriminant power for TH (area under the curve, 0.86; positive predictive value, 80%; negative predictive value, 87%). Patients with baseline LN exhibited increased Enterobacteriaceae and inflammatory and extracellular matrix gene signatures, coupled with reduced levels of butyrate-producing commensals and a respiratory electron transport gene signature. Taxa including Lachnospiraceae and the genus Roseburia were associated with increased respiratory and decreased inflammatory gene signatures, and Aggregatibacter and Blautia bacteria were associated with reduced extracellular matrix gene expression.

CONCLUSIONS

Pediatric patients with CD with LN at diagnosis are less likely to achieve TH. The association between specific microbiota, wound healing gene programs, and LN may suggest future therapeutic targets.

The Gut Microbiome and the Triple Environmental Hit Concept of Inflammatory Bowel Disease Pathogenesis

The incidence of chronic inflammatory bowel diseases (IBDs), such as Crohn's disease (CD) and ulcerative colitis (UC) have significantly increased in recent decades implicating environmental effects. The developmental origin of disease concept provides a theoretical framework by which the complex interplay between environmental factors and host cells, particularly during vulnerable time periods, ultimately cause disease, such as IBD. Epigenetics has been proposed as the underlying mechanism within this concept, turning environmental triggers into stable changes of cellular function. Adding further to the complexity of IBD is the gut microbiome, which is equally responsive to the environment, and can impact host cell function, where recent findings underscore the stochastic and individualized nature of such effects. We review the microbiome literature through a novel triple environmental hit concept (priming, modulation, and trigger) of IBD pathogenesis. We propose that there are at least 3 distinct stages during an individual's lifespan where random/stochastic events driven by environmental influences are necessary for ultimately developing IBD. By this means, we speculate that microbiome-directed therapeutics carry potential for individualized prevention and dynamic treatment of IBD.

BCG epidemiology supports its protection against COVID-19? A word of caution

The COVID-19 pandemic, caused by type 2 Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2), puts all of us to the test. Epidemiologic observations could critically aid the development of protective measures to combat this devastating viral outbreak. Recent observations, linked nation based universal Bacillus Calmette-Guerin (BCG) vaccination to potential protection against morbidity and mortality from SARS-CoV-2, and received much attention in public media. We wished to validate the findings by examining the country based association between COVID-19 mortality per million population, or daily rates of COVID-19 case fatality (i.e. Death Per Case/Days of the endemic [dpc/d]) and the presence of universal BCG vaccination before 1980, or the year of the establishment of universal BCG vaccination. These associations were examined in multiple regression modeling based on publicly available databases on both April 3rd and May 15th of 2020. COVID-19 deaths per million negatively associated with universal BCG vaccination in a country before 1980 based on May 15th data, but this was not true for COVID-19 dpc/d on either of days of inquiry. We also demonstrate possible arbitrary selection bias in such analyses. Consequently, caution should be exercised amidst the publication surge on COVID-19, due to political/economical-, arbitrary selection-, and fear/anxiety related biases, which may obscure scientific rigor. We argue that global COVID-19 epidemiologic data is unreliable and therefore should be critically scrutinized before using it as a nidus for subsequent hypothesis driven scientific discovery.

Progression to colectomy in the era of biologics: A single center experience with pediatric ulcerative colitis

BACKGROUND/PURPOSE

Clinical outcomes in pediatric ulcerative colitis (UC) in the era of biologic agents are poorly defined. We aimed to describe risk factors for colectomy in pediatric UC in the era of infliximab therapy.

METHODS

We reviewed 217 pediatric patients at Texas Children's Hospital with newly diagnosed UC between 2003 and 2015; 117 had a minimum of 5 years of follow-up. Extent of disease at diagnosis, medication exposure, the presence of extraintestinal manifestations (EIMs), and need for surgery were noted.

RESULTS

Average length of follow up was 5.02 ± 2.27 years. Forty-two percent presented with pancolitis. Infliximab was used in 39%, immunomodulators in 65%, and steroids in 89% of patients. EIMs occurred in 24.9% of patients. The cumulative rate of colectomy was 12.9% at 5 years. Children presenting as E2 (Paris Classification) and children prescribed oral steroid monotherapy at diagnosis progressed to surgery faster than any other group. Of the children who received infliximab, females and children less than 5 years old were less likely to respond to therapy.

CONCLUSIONS

The natural course of pediatric UC remains aggressive despite the addition of infliximab to the standard of care and suggests a need for early aggressive clinical intervention.

LEVEL-OF-EVIDENCE RATING

Level IV.

Mucosal Inflammatory and Wound Healing Gene Programs Reveal Targets for Stricturing Behavior in Pediatric Crohn's Disease

BACKGROUND AND AIMS

Ileal strictures are the major indication for resective surgery in Crohn's disease (CD). We aimed to define ileal gene programs present at diagnosis linked with future stricturing behavior during five year follow-up, and to identify potential small molecules to reverse these gene signatures.

METHODS

Antimicrobial serologies and pre-treatment ileal gene expression were assessed in a representative subset of 249 CD patients within the RISK multicenter pediatric CD inception cohort study, including 113 that are unique to this report. These data were used to define genes associated with stricturing behavior and for model testing to predict stricturing behavior. A bioinformatics approach to define small molecules which may reverse the stricturing gene signature was applied.

RESULTS

19 of the 249 patients developed isolated B2 stricturing behavior during follow-up, while 218 remained B1 inflammatory. Using deeper RNA sequencing than in our prior report, we have now defined an inflammatory gene signature including an oncostatin M co-expression signature, tightly associated with extra-cellular matrix (ECM) gene expression in those who developed stricturing complications. We further computationally prioritize small molecules targeting macrophage and fibroblast activation and angiogenesis which may reverse the stricturing gene signature. A model containing ASCA and CBir1 serologies and a refined eight ECM gene set was significantly associated with stricturing development by year five after diagnosis (AUC (95th CI) = 0.82 (0.7-0.94)).

CONCLUSION

An ileal gene program for macrophage and fibroblast activation is linked to stricturing complications in treatment naïve pediatric CD, and may inform novel small molecule therapeutic approaches.

Parental Education May Differentially Impact Pediatric Inflammatory Bowel Disease Phenotype Risk

BACKGROUND

The incidence of pediatric inflammatory bowel diseases (PIBDs: Crohn's disease [CD], ulcerative colitis [UC]) is on the rise around the world. Yet, the critical risk factors for this rising incidence are not well understood. Demographic characteristics of PIBD may improve our understanding of their developmental origins and aid in prevention.

METHODS

Four hundred eighty-eight consecutive PIBD patients diagnosed at Texas Children's Hospital from 13 counties around Houston were studied. An annual incidence map was created by ZIP code of residence at diagnosis by using ArcGIS and the American Community Survey from the US Census Bureau. Correlation between demographic variables and PIBD incidence was examined. A model to explain incidence from different health factors was created in R.

RESULTS

Hispanic children were more likely to be diagnosed with UC (P < 0.01) and unclassified IBD (IBD-U) (P < 0.03) compared with other races/ethnicities. A significant positive correlation (r = 0.35, P < 0.0001) between median household income and PIBD incidence was observed (UC: r = 0.23, P < 0.0001; CD: r = 0.22, P = 0.0004). ZIP codes with majority college-educated adults had a higher incidence of PIBD than ZIP codes with majority high school-educated adults (P < 0.0001). Pediatric cases with CD were more common in ZIP codes where the majority of adults were college educated (P < 0.0001). Pediatric cases with UC, however, were more common in ZIP codes where the majority of adults were high school educated (P = 0.0036).

CONCLUSIONS

Hispanic children more commonly present with UC and IBD-U in southern USA. Household income and/or adult education-related environmental/dietary differences may be important in the developmental origins of PIBD in large metro areas, such as Houston.

Durable Clinical and Biochemical but Not Endoscopic Remission in Pediatric Crohn's Disease on Specific Carbohydrate Diet Monotherapy

The specific carbohydrate diet (SCD) is an exclusion diet that has gained increasing public attention as a treatment option for inflammatory bowel diseases (IBDs: Crohn's Disease (CD) and Ulcerative Colitis (UC)). Studies have demonstrated SCD leads to clinical and biochemical remission. Additional observations had controversial results when mucosal healing, or endoscopic remission was assessed in pediatric CD patients on partial SCD therapy, or SCD as adjunct treatment. There is currently a lack of mucosa-based assessments for pediatric IBD patients on SCD monotherapy. We report three pediatric CD patients who achieved clinical remission on SCD monotherapy, but failed to demonstrate complete mucosal healing with a minimum of one year follow up. This case report highlights that SCD monotherapy in male pediatric CD patients can sustain durable clinical and biochemical remission, but not full mucosal healing.

Efficacy of Fecal Microbiota Transplantation for Clostridium difficile Infection in Children

BACKGROUND & AIMS

Fecal microbiota transplantation (FMT) is commonly used to treat Clostridium difficile infection (CDI). CDI is an increasing cause of diarrheal illness in pediatric patients, but the effects of FMT have not been well studied in children. We performed a multi-center retrospective cohort study of pediatric and young adult patients to evaluate the efficacy, safety, and factors associated with a successful FMT for the treatment of CDI.

METHODS

We performed a retrospective study of 372 patients, 11 months to 23 years old, who underwent FMT at 18 pediatric centers, from February 1, 2004, to February 28, 2017; 2-month outcome data were available from 335 patients. Successful FMT was defined as no recurrence of CDI in the 2 months following FMT. We performed stepwise logistic regression to identify factors associated with successful FMT.

RESULTS

Of 335 patients who underwent FMT and were followed for 2 months or more, 271 (81%) had a successful outcome following a single FMT and 86.6% had a successful outcome following a first or repeated FMT. Patients who received FMT with fresh donor stool (odds ratio [OR], 2.66; 95% CI, 1.39-5.08), underwent FMT via colonoscopy (OR, 2.41; 95% CI, 1.26-4.61), did not have a feeding tube (OR, 2.08; 95% CI, 1.05-4.11), or had 1 less episode of CDI before FMT (OR, 1.20; 95% CI, 1.04-1.39) had increased odds for successful FMT. Seventeen patients (4.7%) had a severe adverse event during the 3-month follow-up period, including 10 hospitalizations.

CONCLUSIONS

Based on the findings from a large multi-center retrospective cohort, FMT is effective and safe for the treatment of CDI in children and young adults. Further studies are required to optimize the timing and method of FMT for pediatric patients-factors associated with success differ from those of adult patients.

Diagnostic delay and colectomy risk in pediatric ulcerative colitis

BACKGROUND/PURPOSE

Diagnostic delay or time to diagnosis, and its relationship with colectomy risk has been studied in adult Inflammatory Bowel Disease (IBD), but rarely in pediatric IBD (PIBD), especially pediatric ulcerative colitis (P-UC), which often has a more severe course than adult UC. This study compared the relationship between diagnostic delay and colectomy in P-UC.

METHODS

The medical records of P-UC patients, ages <18 years, diagnosed at Texas Children's Hospital from 2012 to 2018 were examined. We identified 106 P-UC patients, where the onset of symptoms of IBD (i.e. fever, diarrhea, blood in stool, weight loss, abdominal pain) could be clearly identified.

RESULTS

Twenty (20 = 18.9%) patients progressed to colectomy, and 86 did not. There was no significant difference in diagnostic delay between the patients undergoing colectomy with UC (C-UC) and those with no colectomy (NC-UC) (p = 0.2192). The median (C-UC = 7.1 weeks; NC-UC = 11.9 weeks) and mean (C-UC = 16.5 weeks±4.7; NC-UC = 20.1 ± 2.6) diagnostic delay actually tended to be shorter in C-UC compared to NC-UC. Fecal calprotectin levels were significantly higher (p = 0.0228) in C-UC than NC-UC patients at diagnosis.

CONCLUSIONS

Shorter time to diagnosis may reflect disease severity at the time of disease onset and also a more aggressive subsequent course of P-UC. The significantly higher level of fecal calprotectin in the C-UC patients at diagnosis provided biologic/biochemical support for our conclusion.

LEVELS OF EVIDENCE

Prognosis study, Level III evidence.

Fecal microbiota transplantation in a toddler after heart transplant was a safe and effective treatment for recurrent Clostridiodes difficile infection: A case report

Pediatric recipients of SOT have a significantly increased risk of Clostridiodes (formerly Clostridium) difficile infection (CDI), which is associated with adverse outcomes after SOT. Alterations to the intestinal microbiota community structure increase the risk of CDI. FMT is a safe and effective treatment for recurrent CDI in immunocompetent children and adults. While there are increasing data that FMT in immunosuppressed patients is safe and effective without increased risk of infection, data regarding safety and efficacy of FMT in children after SOT are limited. To our knowledge, we report the youngest immunocompromised patient to undergo FMT and the third overall case of FMT in a child after HTx. Our patient presented with five episodes of rCDI in 6 months, and 16S rRNA genetic analysis revealed significant loss of overall microbiota community structure and diversity prior to FMT compared with a donor and a healthy, age-matched control. After FMT, marked and prolonged (at least 16 months) shifts in the recipient microbiota community structure and diversity were evident, approaching that of donor and healthy, age-matched control. FMT was well tolerated, restored microbial diversity without any graft or transplant complications, and prevented further rCDI episodes after more than 4 years of follow-up.

Proceedings of the 2017 ASPEN Research Workshop-Gastric Bypass: Role of the Gut

The goal of the National Institutes of Health-funded American Society for Parenteral and Enteral Nutrition 2017 research workshop (RW) "Gastric Bypass: Role of the Gut" was to focus on the exciting research evaluating gut-derived signals in modulating outcomes after bariatric surgery. Although gastric bypass surgery has undoubted positive effects, the mechanistic basis of improved outcomes cannot be solely explained by caloric restriction. Emerging data suggest that bile acid metabolic pathways, luminal contents, energy balance, gut mucosal integrity, as well as the gut microbiota are significantly modulated after bariatric surgery and may be responsible for the variable outcomes, each of which was rigorously evaluated. The RW served as a timely and novel academic meeting that brought together clinicians and researchers across the scientific spectrum, fostering a unique venue for interdisciplinary collaboration among investigators. It promoted engaging discussion and evolution of new research hypotheses and ideas, driving the development of novel ameliorative, therapeutic, and nonsurgical interventions targeting obesity and its comorbidities. Importantly, a critical evaluation of the current knowledge regarding gut-modulated signaling after bariatric surgery, potential pitfalls, and lacunae were thoroughly addressed.

Carbohydrate Monotony as Protection and Treatment for Inflammatory Bowel Disease

The nutritional developmental origins of inflammatory bowel disease[s] (IBDs: Crohn's disease or Crohn disease [CD] and ulcerative colitis [UC]) and their diet-based treatments continue to receive increasing attention. There is growing evidence for the success of nutrition-based treatments, such as exclusive enteral nutrition [EEN] and the specific carbohydrate diet [SCD], in both paediatric and adult patients. Beyond these two dietary interventions, symptomatic benefit in IBD has also been shown from a gluten-free diet [GFD] and paleolithic diet [PALEO], among others. These nutritional therapies may point to critical factors in not only the pathology, but also the pathogenesis of the disease group. It is difficult, however, to discern a common element within the large number of diet-based causation theories [e.g. emulsifiers, processed foods, refrigeration, increased total fat intake, low fibre intake, carbohydrate dominant food, etc.] and the varied dietary treatments of IBD. This Viewpoint article highlights that carbohydrate variation links diet-based causation theories, and that carbohydrate monotony or persistence is the commonly shared characteristic of diet-based IBD therapy. Further research directed towards carbohydrate monotony may critically advance the prevention and treatment of these highly morbid conditions.

Weight loss is a sufficient and economical single outcome measure of murine dextran sulfate sodium colitis

Inflammatory bowel diseases (IBD: Crohn's disease and ulcerative colitis) are becoming common around the world without a cure. Animal models of colitis have become instrumental in IBD research. The dextran sulfate sodium (DSS) induced murine colitis model is likely the most utilized due to its simplicity and reproducibility with over 4000 publications on PubMed, where weight loss is the most commonly used and reliable positive correlate. We predicted at current state of art, that the DSS colitis model can be optimized by using weight loss as a single cost‐saving outcome measure. Twenty recent and consecutive publications using the DSS model in PubMed were selected for review. Guarded cost estimations for additional outcome measures of colitis beyond weight loss were performed. In all manuscripts (100%), weight loss corroborated the conclusions. Average excess cost for examining additional measures of colitis was approximately $6700 per publication. Two studies (10.5%) were estimated to have spent over $20,000 in excess. Additional measures of colitis either supported the final conclusions found with weight loss, or lead to indeterminate results. Potential annual savings from following our guidance were calculated to be over $60,000 for and IBD lab. We conclude that weight loss is a sufficient, objective, and economical outcome measure of DSS‐induced colitis in mice.

Variation in Care in the Management of Children With Crohn's Disease: Data From a Multicenter Inception Cohort Study

BACKGROUND

Variation in care is common in medical practice. Reducing variation in care is shown to improve quality and increase favorable outcomes in chronic diseases. We sought to identify factors associated with variation in care in children with newly diagnosed Crohn's disease (CD).

METHODS

Prospectively collected data from a 28-site multicenter inception CD cohort were analyzed for variations in diagnostic modalities, treatment, and follow-up monitoring practices, along with complicated disease outcomes over 3 years in 1046 children. Generalized linear mixed effects models were used to investigate the intercenter variations in each outcome variable.

RESULTS

The mean age at diagnosis was 12 years, and 25.9% were nonwhite. The number of participants ranged from 5 to 112 per site. No variation existed in the initial diagnostic approach. When medication exposure was analyzed, steroid exposure varied from 28.6% to 96.9% (P < 0.01) within 90 days, but variation was not significant over a 3-year period (P = 0.13). Early anti-tumor necrosis factor (anti-TNF) exposure (within 90 days) varied from 2.1% to 65.7% (P < 0.01), but variation was not significant over a 3-year period (P > 0.99). Use of immunomodulators (IMs) varied among centers both within 90 days (P < 0.01) and during 3 years of follow-up (P < 0.01). A significant variation was seen at the geographic level with follow-up small bowel imaging and colonoscopy surveillance after initial therapy.

CONCLUSIONS

Intercenter variation in care was seen with the initial use of steroids and anti-TNF, but there was no difference in total 3-year exposure to these drugs. Variation in the initiation and long-term use of IMs was significant among sites, but further research with objective measures is needed to explain this variation of care. Small bowel imaging or repeat colonoscopy in CD patients was not uniformly performed across sites. As our data show the widespread existence of variation in care and disease monitoring at geographic levels among pediatric CD patients, future implementation of various practice strategies may help reduce the variation in care.

Blood-Derived DNA Methylation Signatures of Crohn's Disease and Severity of Intestinal Inflammation

BACKGROUND & AIMS

Crohn's disease is a relapsing and remitting inflammatory disorder with a variable clinical course. Although most patients present with an inflammatory phenotype (B1), approximately 20% of patients rapidly progress to complicated disease, which includes stricturing (B2), within 5 years. We analyzed DNA methylation patterns in blood samples of pediatric patients with Crohn's disease at diagnosis and later time points to identify changes that associate with and might contribute to disease development and progression.

METHODS

We obtained blood samples from 164 pediatric patients (1-17 years old) with Crohn's disease (B1 or B2) who participated in a North American study and were followed for 5 years. Participants without intestinal inflammation or symptoms served as controls (n = 74). DNA methylation patterns were analyzed in samples collected at time of diagnosis and 1-3 years later at approximately 850,000 sites. We used genetic association and the concept of Mendelian randomization to identify changes in DNA methylation patterns that might contribute to the development of or result from Crohn's disease.

RESULTS

We identified 1189 5'-cytosine-phosphate-guanosine-3' (CpG) sites that were differentially methylated between patients with Crohn's disease (at diagnosis) and controls. Methylation changes at these sites correlated with plasma levels of C-reactive protein. A comparison of methylation profiles of DNA collected at diagnosis of Crohn's disease vs during the follow-up period showed that, during treatment, alterations identified in methylation profiles at the time of diagnosis of Crohn's disease more closely resembled patterns observed in controls, irrespective of disease progression to B2. We identified methylation changes at 3 CpG sites that might contribute to the development of Crohn's disease. Most CpG methylation changes associated with Crohn's disease disappeared with treatment of inflammation and might be a result of Crohn's disease.

CONCLUSIONS

Methylation patterns observed in blood samples from patients with Crohn's disease accompany acute inflammation; with treatment, these change to resemble methylation patterns observed in patients without intestinal inflammation. These findings indicate that Crohn's disease-associated patterns of DNA methylation observed in blood samples are a result of the inflammatory features of the disease and are less likely to contribute to disease development or progression.

Fecal microbiota transplantation: great potential with many challenges

In January of 2019, Samuel P. Costello and colleagues published a wonderfully executed, double blind placebo-controlled trial on fecal microbiota transplantation (FMT) versus autologous stool as placebo in mild to moderately active adult ulcerative colitis [UC: one type of inflammatory bowel disease (IBD)] patients. This review-commentary examines the current state of knowledge on human gut microbiome (live microbiota + their products and surrounding environment, i.e., fecal matter) and microbial therapeutics from a gastrointestinal (GI) clinician's standpoint. The varied forms of dysbiosis as the target of FMT, recipient donor and placebo considerations are also discussed in respect to randomized control trials in IBD [and the lack thereof in Crohn's disease (CD)] with this unconventional treatment modality.