Microbial Shifts and Shorter Time to Bowel Resection Surgery Associated with C. difficile in Pediatric Crohn's Disease

Clinical Features of Crohn's Disease Stratified by Age at Diagnosis According to Montreal Classification

Aim

The differences of clinical characteristics stratified by age at diagnosis especially according to Montreal classification were rarely studied in China. This study aimed to evaluate and compare the clinical features in various groups of CD patients stratified by age at diagnosis.

Methods

A cross-sectional study of CD patients was conducted through a stratified sampling according to Montreal classification. Patients were divided into three groups by age at diagnosis: group A1 (<17 years old), group A2 (17 to 40 years old), and group A3 (>40 years old). The clinical characteristics, laboratory tests, radiographic, and endoscopic features were analyzed by statistics.

Results

We enrolled 259 CD patients for the study. There was male predominance under 40 years old. Compared to group A1, more female patients were presented in group A3. There were more patients had perianal fistulas in group A1 compared to group A2 and group A3. Compared with group A1, patients in group A2 were associated with lower total protein (TP) levels. The mean TP and platelet count (PC) levels in group A3 were lower than group A1. Patients in group A1 had a lower rate of stricturing (B2) disease behavior than group A2 and group A3, and patients in group A3 who had a B2 disease behavior were higher than group A2. Those differences could guide early treatment or inventions for CD patients who might progress to a more complex disease behavior.

Conclusion

CD patients stratified by age at diagnosis according to Montreal classification had different clinical symptoms, laboratory test results as well as disease locations and behaviors.

Gut microbiome and mycobiome in inflammatory bowel disease patients with Clostridioides difficile infection

Background

Clostridium difficile infection (CDI) is common in patients with inflammatory bowel disease (IBD) and has been reported as a risk factor for poor outcome. However, gut microbiome and mycobiome of IBD patients with CDI have been barely investigated. This study aimed to assess the gut microbiome and mycobiome in IBD patients with CDI.

Methods

We collected fecal samples from patients with active IBD and concomitant CDI (IBD-CDI group, n=25), patients with active IBD and no CDI (IBD-only group, n=51), and healthy subjects (HC, n=40). Patients' characteristics including demographic data, disease severity, and medication history were collected. Metagenomic sequencing, taxonomic and functional analysis were carried out in the samples.

Results

We found that the bacterial alpha diversity of the IBD-CDI group was decreased. The bacterial and fungal beta diversity variations between IBD patients and HC were significant, regardless of CDI status. But the IBD-CDI group did not significantly cluster separately from the IBD-only group. Several bacterial taxa, including Enterococcus faecium, Ruminococcus gnavus, and Clostridium innocuum were overrepresented in the IBD-CDI group. Furthermore, IBD patients with CDI were distinguished by several fungal taxa, including overrepresentation of Saccharomyces cerevisiae. We also identified functional differences in IBD patients with CDI include enrichment of peptidoglycan biosynthesis. The network analysis indicated specific interactions between microbial markers in IBD-CDI patients.

Conclusion

IBD patients with CDI had pronounced microbial dysbiosis. Gut micro-ecological changes in IBD patients with CDI might provide insight into the pathological process and potential strategies for diagnosis and treatment in this subset of patients.

Hospitalization With Clostridioides difficile in Pediatric Inflammatory Bowel Disease: a Population-Based Study

OBJECTIVES

Several studies have demonstrated higher rates of Clostridioides difficile infection (CDI) in adults with inflammatory bowel disease (IBD). We conducted a population-based study comparing the risk of hospitalization with CDI in children with and without IBD.

METHODS

Using health administrative data and validated algorithms, we identified all children (<16 years) diagnosed with IBD in 5 Canadian provinces, then age and sex matched to 5 children without IBD. Province-specific 5-year incidence rates of hospitalization with CDI were pooled and generalized linear mixed-effects models were used to estimate the crude incidence rate ratio (IRR) comparing (1) children with and without IBD and (2) children with Crohn disease and ulcerative colitis. Hazard ratios (HR) from Cox proportional hazards models adjusting for age, sex, rural/urban household, and income were pooled using fixed-effects models.

RESULTS

The incidence rate of CDI identified during hospitalization was 49.06 [95% confidence interval (CI), 39.40-61.08] per 10,000 person-years (PY) in 3593 children with IBD compared to 0.39 (95% CI, 0.13-1.21) per 10,000 PY in 16,284 children without IBD (crude IRR, 133.4, 95% CI, 42.1-422.7; adjusted HR, 68.2, 95% CI, 24.4-190.4). CDI was identified less often in children with Crohn disease than ulcerative colitis (crude IRR, 0.51, 95% CI, 0.32-0.82; adjusted HR, 0.69, 95% CI, 0.46-1.05).

CONCLUSIONS

Children with IBD have a markedly higher incidence of CDI identified during a hospitalization relative to children without IBD. Consequently, symptomatic children with IBD who are hospitalized should be screened for CDI.

Antibiotic exposure prevents acquisition of beneficial metabolic functions in the preterm infant gut microbiome

BACKGROUND

Aberrations in the preterm microbiome following antibiotic therapy have been reported in previous studies. The objective of this study was to probe potential underlying mechanisms between this observation and susceptibility to adverse prematurity-related outcomes.

RESULTS

Metagenomic shotgun sequencing was performed on 133 stool and 253 skin samples collected at 1 and 3 weeks of age from 68 infants born at <36 weeks postmenstrual age and birth weight <2000 g. After accounting for gestational age and maternal antibiotics, the distribution of organisms in all samples and the corresponding metabolic pathway abundance were compared between infants exposed to postnatal antibiotics and antibiotics-naïve infants. In antibiotic-naïve infants, gestational and postnatal age imparted similar trajectories on maturation of the microbial community and associated metabolic functional capacity, with postnatal age exerting greater contribution. Antibiotic exposure was associated with reversal in maturation trajectory from the first week to the third week of age (p< 0.001). Butyrate-producing genera, including Clostridium and Blautia, were significantly more abundant in antibiotic-naïve neonates at 3 weeks postnatal age. Correspondingly, metabolic pathways required for short-chain fatty acid synthesis were significantly increased in antibiotic-naïve infants, but not in antibiotic-exposed neonates, at 3 weeks after birth.

CONCLUSIONS

Early brief antibiotic exposure markedly disrupts developmental trajectory of the neonatal microbiome and its corresponding functional capacity. Our findings may provide a mechanistic explanation for the known associations between antibiotic use and adverse outcomes in preterm infants. Video Abstract.

Risk factors for Clostridioides difficile infection in children and adolescents with inflammatory bowel disease: a systematic review and meta-analysis

BACKGROUND

Risk factors and consequences associated with Clostridioides difficile infection (CDI) in children and adolescents with inflammatory bowel disease (IBD) are still uncertain. We conduct a systematic review and meta-analysis to assess risk factors and outcomes associated with CDI in children and adolescents with IBD.

METHODS

PubMed, EMBASE and Cochrane Library databases were searched from inception to 24th February, 2021. Studies investigating risk factors, bowel surgery rate in pediatric IBD patients with and without CDI were included. Random-effects model was used for calculating summary estimates. Newcastle-Ottawa scale (NOS) was used for quality assessment.

RESULTS

Fourteen studies, comprising 17,114 patients, were included. There was a significant association between 5-aminosalicylic acid (5-ASA) use and CDI [odds ratio (OR) = 1.95, 95% confidence interval (CI) 1.26-3.03], with minimal heterogeneity (I² = 0.00%). Increased risk of active disease (OR = 4.66, 95% CI 2.16-10.07) were associated with CDI in those studies performed in high quality score (NOS > 6) and significantly higher CDI rates in studies conducted outside USA (OR = 2.94, 95% CI 1.57-5.58). The bowel surgery rate in IBD with CDI was 3.8-57.1%, compared to that in IBD without CDI (0-21.3%). All studies were of moderate to high quality.

CONCLUSIONS

5-ASA use and active disease might be risk factors associated with CDI in children and adolescents with IBD. Bowel surgery rates associated with CDI in IBD patients varied greatly. Large-scale clinical studies on CDI in children and adolescents with IBD are still needed to verify risk factors and outcomes.

Decreased secondary faecal bile acids in children with ulcerative colitis and Clostridioides difficile infection

BACKGROUND

Patients with ulcerative colitis (UC) have an increased risk of Clostridioides difficile infection (CDI). There is a well-documented relationship between bile acids and CDI.

AIMS

To evaluate faecal bile acid profiles and gut microbial changes associated with CDI in children with UC.

METHODS

This study was conducted at Children's Hospital Los Angeles. Faecal bile acids and gut microbial genes related to bile acid metabolism were measured in 29 healthy children, 23 children with mild to moderate UC without prior CDI (UC group), 16 children with mild to moderate UC with prior CDI (UC+CDI group) and 10 children without UC with prior CDI (CDI group).

RESULTS

Secondary faecal bile acids, especially lithocholic acid (3.296 vs 10.793, P ≤ 0.001) and ursodeoxycholic acid (7.414 vs 10.617, P ≤ 0.0001), were significantly lower in children with UC+CDI when compared to UC alone. Secondary faecal bile acids can predict disease status between these groups with 84.6% accuracy. Additionally, gut microbial genes coding for bile salt hydrolase, 7α-hydroxysteroid dehydrogenase and 7α/β-dehydroxylation were all diminished in children with UC+CDI compared to children with UC alone.

CONCLUSIONS

Bile acids can distinguish between children with UC based on their prior CDI status. Bile acid profile changes can be explained by gut microbial genes encoding for bile salt hydrolase, 7α-hydroxysteroid dehydrogenase and 7α/β-dehydroxylation. Bile acid profiles may be helpful as biomarkers to identify UC children who have had CDI and may serve as future therapeutic targets.

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.

Updating changes in human gut microbial communities associated with Clostridioides difficile infection

Clostridioides difficile is the causative agent of antibiotic-associated diarrhea, a worldwide public health problem. Different factors can promote the progression of C. difficile infection (CDI), mainly altered intestinal microbiota composition. Microbial species belonging to different domains (i.e., bacteria, archaea, eukaryotes, and even viruses) are synergistically and antagonistically associated with CDI. This review was aimed at updating changes regarding CDI-related human microbiota composition using recent data and an integral approach that included the different microorganism domains. The three domains of life contribute to intestinal microbiota homeostasis at different levels in which relationships among microorganisms could explain the wide range of clinical manifestations. A holistic understanding of intestinal ecosystem functioning will facilitate identifying new predictive factors for infection and developing better treatment and new diagnostic tools, thereby reducing this disease's morbidity and mortality.

MICROBIOTA INSIGHTS IN CLOSTRIDIUM DIFFICILE INFECTION AND INFLAMMATORY BOWEL DISEASE

Inflammatory bowel disease (IBD) is characterized by chronic intestinal inflammation that includes Crohn´s disease (CD) and ulcerative colitis (UC). Although the etiology is still unknown, some specific factors have been directly related to IBD, including genetic factors, abnormal intestinal immunity, and/or gut microbiota modifications. Recent findings highlight the primary role of the gut microbiota closely associated with a persistent inappropriate inflammatory response. This gut environment of dysbiosis in a susceptible IBD host can increasingly worsen and lead to colonization and infection with some opportunistic pathogens, especially Clostridium difficile. C. difficile is an intestinal pathogen considered the main cause of antibiotic-associated diarrhea and colitis and an important complication of IBD, which can trigger or worsen an IBD flare. Recent findings have highlighted the loss of bacterial cooperation in the gut ecosystem, as well as the pronounced intestinal dysbiosis, in patients suffering from IBD and concomitant C. difficile infection (CDI). The results of intestinal microbiota studies are still limited and often difficult to compare because of the variety of disease conditions. However, these data provide important clues regarding the main modifications and interrelations in the complicated gut ecosystem to better understand both diseases and to take advantage of the development of new therapeutic strategies. In this review, we analyze in depth the gut microbiota changes associated with both forms of IBD and CDI and their similarity with the dysbiosis that occurs in CDI. We also discuss the metabolic pathways that favor the proliferation or decrease in several important taxa directly related to the disease.