Host Immune Response to Clostridium difficile Infection in Inflammatory Bowel Disease Patients

Diagnosis and Management of Clostridioides difficile in Inflammatory Bowel Disease

Patients with inflammatory bowel disease (IBD) have an increased risk of Clostridioides difficile infection (CDI), which can lead to worse IBD outcomes. The diagnosis of CDI in patients with IBD is complicated by higher C. difficile colonization rates and shared clinical symptoms of intestinal inflammation. Traditional risk factors for CDI, such as antibiotic exposure, may be lacking in patients with IBD because of underlying intestinal microbiota dysbiosis. Although CDI disproportionately affects people with IBD, patients with IBD are typically excluded from CDI clinical trials creating a knowledge gap in the diagnosis and management of these 2 diseases. This narrative review aims to provide a comprehensive overview of the diagnosis, treatment, and prevention of CDI in patients with IBD. Distinguishing CDI from C. difficile colonization in the setting of an IBD exacerbation is important to avoid treatment delays. When CDI is diagnosed, extended courses of anti- C. difficile antibiotics may lead to better CDI outcomes. Regardless of a diagnosis of CDI, the presence of C. difficile in a patient with IBD should prompt a disease assessment of the underlying IBD. Microbiota-based therapies and bezlotoxumab seem to be effective in preventing CDI recurrence in patients with IBD. Patients with IBD should be considered at high risk of CDI recurrence and evaluated for a preventative strategy when diagnosed with CDI. Ultimately, the comanagement of CDI in a patient with IBD requires a nuanced, patient-specific approach to distinguish CDI from C. difficile colonization, prevent CDI recurrence, and manage the underlying IBD.

Walk before you run: Feasibility challenges and lessons learned from the PROCLAIM study, a multicenter randomized controlled trial of misoprostol for prevention of recurrent Clostridioides difficile during COVID-19

We analyzed our challenging experience with a randomized controlled trial of misoprostol for prevention of recurrent C. difficile. Despite careful prescreening and thoughtful protocol modifications to facilitate enrollment, we closed the study early after enrolling just 7 participants over 3 years. We share lessons learned, noting the importance of feasibility studies, inclusion of biomarker outcomes, and dissemination of such findings to inform future research design and implementation successes.

Prevalence of Clostridioides difficile Infection After Ileal Pouch-anal Anastomosis in Patients With Chronic Antibiotic-dependent Pouchitis and Crohn's-like Disease of the Pouch

BACKGROUND

Recurrent or chronic antibiotic therapy is a therapeutic hallmark of chronic antibiotic-dependent pouchitis (CADP) or Crohn's-like disease of the pouch. Antibiotics alter the gut microbiome, which may increase the risk of Clostridioides difficile infection (CDI). The aim of this study was to determine the prevalence of CDI in patients with CADP and Crohn's-like disease of the pouch.

METHODS

We conducted a retrospective cohort study of patients with CADP or Crohn's-like disease of the pouch at a tertiary academic medical center. The primary outcome was prevalence of CDI. Secondary outcomes included antibiotic therapy at the time of CDI diagnosis, treatment regimens for CDI, and subsequent outcomes.

RESULTS

Overall, 18 of 198 (9.1%) included patients developed CDI. Treatment with antibiotics at the time of CDI diagnosis occurred in 7 of 18 (39%) patients. Preoperative history of CDI was significantly associated with increased risk of developing CDI following ileal pouch anal anastomosis (IPAA) compared with those with no prior history of CDI (12 of 18 [67%] vs 11 of 180 [6%]; P < .001). In 16 of 18 (89%) patients, CDI treatment was initiated with predominantly oral vancomycin (72%) or metronidazole (17%).

CONCLUSION

Although chronic inflammatory conditions of the pouch arise postoperatively, the prevalence of CDI in this population appears to be similar compared with the general population of patients with inflammatory bowel disease prior to and post IPAA. Preoperative CDI appears to be the greatest risk for postoperative CDI and may require extra vigilance in the assessment of CDI after IPAA.

Humoral Immune Response to Clostridioides difficile Toxins A and B in Hospitalized Immunocompromised Patients With C difficile Infection

Background

The humoral immune response to Clostridioides difficile toxins in C difficile infection (CDI) is incompletely characterized in immunocompromised hosts (ICHs).

Methods

We conducted a prospective study of hospitalized adults with CDI, with and without immunosuppression (hematologic malignancy, active solid tumor, solid organ or stem cell transplant, inflammatory bowel disease, autoimmune disease, congenital or acquired immunodeficiency, asplenia, chronic receipt of high-dose steroids, or receipt of immunosuppressing medications within 12 months). Serum and stool antibody concentrations of immunoglobulin (Ig)M, IgG, and IgA to C difficile toxins A and B at treatment days 0, 3, and 10–14 were compared.

Results

Ninety-eight subjects (47 ICH; 51 non-ICH) were enrolled. Baseline serum antitoxin A and B antibody levels were similar. At day 3, ICHs demonstrated lower serum levels of antitoxin A IgG, antitoxin A IgA, and antitoxin B IgA (all P < .05). At day 10–14, lower antitoxin A IgG concentrations were observed in ICHs (ICH, 21 enzyme-linked immunosorbent assay [ELISA] units; interquartile range [IQR], 16.4–44.6) compared with non-ICH subjects (49.0 ELISA units; IQR, 21.5–103; P = .045). In stool, we observed lower concentrations of antitoxin B IgA antibodies at baseline and at day 3 for ICH subjects, with a notable difference in concentrations of antitoxin B IgA at day 3 (ICH, 6.7 ELISA units [IQR, 1.9–13.9] compared with non-ICH, 18.1 ELISA units [IQR, 4.9–31.7]; P = .003).

Conclusions

The ICHs with CDI demonstrated lower levels of C difficile antitoxin antibodies in serum and stool during early CDI therapy compared with non-ICHs. These data provide insight into the humoral response to CDI in ICHs.

Host Immune Markers Distinguish Clostridioides difficile Infection From Asymptomatic Carriage and Non-C. difficile Diarrhea

BACKGROUND

Recent data indicate that Clostridioides difficile toxin concentrations in stool do not differentiate between C. difficile infection (CDI) and asymptomatic carriage. Thus, we lack a method to distinguish a symptomatic patient with CDI from a colonized patient with diarrhea from another cause. To address this, we evaluated markers of innate and adaptive immunity in adult inpatients with CDI (diagnosed per US guidelines), asymptomatic carriage, or non-CDI diarrhea.

METHODS

CDI-NAAT patients had clinically significant diarrhea and positive nucleic acid amplification testing (NAAT) and received CDI treatment. Carrier-NAAT patients had positive stool NAAT but no diarrhea. NAAT-negative patients (with and without diarrhea) were also enrolled. A panel of cytokines and anti-toxin A and B immunoglobulin (Ig) were measured in serum; calprotectin and anti-toxin B Ig A/G were measured in stool. NAAT-positive stool samples were tested by an ultrasensitive toxin assay (clinical cutoff, 20 pg/mL).

RESULTS

Median values for interleukin (IL)-4, IL-6, IL-8, IL-10, IL-15, granulocyte colony-stimulating factor (GCSF), MCP-1, tumor necrosis factor α (TNF-α), and IgG anti-toxin A in blood and IgA/G anti-toxin B in stool were significantly higher in CDI patients compared with all other groups (P < .05). Concentration distributions for IL-6, GCSF, TNF-α, and IgG anti-toxin A in blood, as well as IgA and IgG anti-toxin B in stool, separated CDI patients from all other groups.

CONCLUSIONS

Specific markers of innate and adaptive immunity distinguish CDI from all other groups, suggesting potential clinical utility for identifying which NAAT- and toxin-positive patients with diarrhea truly have CDI.

Natural Clostridioides difficile Toxin Immunization in Colonized Infants

BACKGROUND

Clostridioides (Clostridium) difficile colonization is common among infants. Serological sequelae of infant C. difficile colonization are poorly understood.

METHODS

In this prospective cohort study of healthy infants, stools serially collected between ages 1-2 and 9-12 months were tested for non-toxigenic and toxigenic C. difficile (TCD). Cultured isolates underwent whole-genome sequencing. Serum collected at 9-12 months underwent measurement of IgA, IgG, and IgM against TCD toxins A and B and neutralizing antibody (NAb) titers against toxin B. For comparison, antitoxin IgG and NAb were measured in cord blood from 50 mothers unrelated to study infants.

RESULTS

Among 32 infants, 16 (50%) were colonized with TCD; 12 were first colonized >1 month before serology measurements. A variety of sequence types were identified, and there was evidence of putative in-home (enrolled siblings) and outpatient clinic transmission. Infants first colonized with TCD >1 month prior had significantly greater serum antitoxin IgA and IgG against toxins A (P = .02 for both) and B (P = .009 and .008, respectively) compared with non-TCD-colonized infants, and greater IgG compared with unrelated cord blood (P = .005). Five of 12 (42%) colonized infants had detectable NAb titers compared with zero non-TCD-colonized infants (P = .02). Breastfeeding was not associated with differences in serological measurements.

CONCLUSIONS

TCD colonization is associated with a humoral immune response against toxins A and B, with evidence of toxin B neutralization in vitro. The extent and duration of protection against CDI later in life afforded by natural C. difficile immunization events require further investigation.

Lemon Exosome-like Nanoparticles-Manipulated Probiotics Protect Mice from C. d iff Infection

Clostridioides difficile (C. diff) is the leading cause of antibiotic-associated colitis. Here, we report that lemon exosome-like nanoparticles (LELNs) manipulated probiotics to inhibit C. diff infection (CDI). LELN-manipulated Lactobacillus rhamnosus GG (LGG) and Streptococcus thermophilus ST-21 (STH) (LELN-LS) decrease CDI mortality via an LELN-mediated increase in bile resistance and gut survivability. LELN-LS treatment increases the AhR ligands indole-3-lactic acid (I3LA) and indole-3-carboxaldehyde (I3Ald), leading to induction of IL-22, and increases lactic acid leading to a decrease of C. diff fecal shedding by inhibiting C. diff growth and indole biosynthesis. A synergistic effect between STH and LGG was identified. The STH metabolites inhibit gluconeogenesis of LGG and allow fructose-1,6-bisphosphate (FBP) to accumulate in LGG; accumulated FBP then activates lactate dehydrogenase of LGG (LGG-LDH) and enhances production of lactic acid and the AhR ligand. Our findings provide a new strategy for CDI prevention and treatment with a new type of prebiotics.

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LELNs-manipulated probiotics protect mice from C. diff infection

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LELNs manipulation modulates gut metabolomics composition

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Cross talk between LGG and STH enhances production of lactic acid and AhR ligands

Humoral response to Clostridium difficile in inflammatory bowel disease, including correlation with immunomodulatory treatment

Background and Aim

An abnormal immune response to intestinal bacteria has been observed in Crohn's disease (CD). Clostridium difficile infection incidence and severity are increased in CD, but reports on the humoral response have provided conflicting results. We aimed to shed light on the possible role of C. difficile in CD pathogenesis by paying attention to the influence of immunomodulatory treatment on the humoral response.

Methods

A total of 71 consecutive outpatients with CD, 67 with ulcerative colitis (UC), and 121 healthy controls were analyzed for serum IgA and IgG to C. difficile toxins A and B.

Results

IgA levels were similar in all study groups. IgG to toxin A was increased similarly in CD and UC (P = 0.02 for both). In contrast, IgG to toxin B was elevated only in CD patients not receiving disease-modifying anti-inflammatory bowel disease drugs (DMAID) (n = 16) (P = 0.0001), while the CD medication subgroup (n = 47) had a level similar to healthy controls. The UC results were not influenced by DMAID treatment.

Conclusion

Our findings add support to the idea of a disturbed interaction between intestinal cells and the microbiota being part of the CD disease mechanism. An abnormal immune response to C. difficile toxin B may be a critical component of this interaction.

Low Frequency of Opportunistic Infections in Patients Receiving Vedolizumab in Clinical Trials and Post-Marketing Setting

Background

Vedolizumab (ENTYVIO) is a humanized α4β7 integrin antagonist approved for the treatment of inflammatory bowel disease, which selectively blocks gut-specific lymphocyte trafficking. We evaluated the risk of opportunistic infections of interest in patients treated with vedolizumab.

Methods

We determined the frequency of opportunistic infections and tuberculosis in patients receiving vedolizumab in phase 3 clinical trials and post-marketing settings. We also evaluated adverse events reported in the post-marketing setting in patients with a history of or concurrent hepatitis B/C virus infection.

Results

The incidence of opportunistic infections in patients receiving vedolizumab was 0.7 (GEMINI 1 and 2 clinical trials) and 1.0 (long-term safety study) per 100 patient-years, with 217 events reported in approximately 114,071 patient-years of exposure (post-marketing setting). Most opportunistic infections were nonserious and the majority of patients continued treatment with vedolizumab. Clostridium difficile was the most commonly reported infection, with an incidence rate of 0.5 per 100 patient-years (clinical trials). Tuberculosis was reported at 0.1 per 100 patient-years (clinical trials), with 7 events in the post-marketing setting. No tuberculosis-related deaths were reported in either setting. No cases of progressive multifocal leukoencephalopathy were reported. In 29 patients with a history of or concurrent hepatitis B/C infection in the post-marketing setting, no viral reactivation was observed.

Conclusions

Clinical trials and post-marketing data showed that the rate of serious opportunistic infections in patients receiving vedolizumab was low and most patients could continue vedolizumab treatment. The frequency of tuberculosis infection was also low and no hepatitis B/C viral reactivation was reported.

Risk Factors for Clostridium difficile Isolation in Inflammatory Bowel Disease: A Prospective Study

INTRODUCTION

Clostridium difficile is the most commonly isolated stool pathogen in inflammatory bowel disease (IBD). Traditional risk factors for C. difficile may not exist in patients with IBD, and no prior studies have assessed the risk factors for the isolation of C. difficile in both symptomatic and asymptomatic IBD outpatients.

METHODS

We prospectively recruited consecutive IBD patients presenting to our outpatient clinic between April 2015 and February 2016. We excluded patients with a diverting ostomy or ileoanal pouch. Demographics, healthcare exposures, medical therapies and disease activity were recorded from medical charts or surveys. A rectal swab was performed from which toxigenic culture and PCR analysis for the presence of toxin and fluorescent PCR ribotyping were performed. The primary outcome of interest was isolation of toxigenic C. difficile.

RESULTS

A total of 190 patients were enrolled in this prospective study including 137 (72%) with Crohn's disease and 53 (28%) with ulcerative colitis. At the time of enrollment, 69 (36%) had clinically active disease. Sixteen (8.4%) patients had toxigenic C. difficile isolated on rectal swab at enrollment and four (2.1%) patients had non-toxigenic C. difficile cultured. Mixed infection with more than one toxigenic isolate was present in 5/16 (31.3%) individuals. Patients with CD with a toxin positive isolate were more likely to have a history of CDI in the past 12 months (40 vs. 11.02%, p = 0.027) and an emergency department visit in the past 12 weeks (50 vs. 20.63%, p = 0.048). In UC, individuals with isolation of C. difficile were more likely to be hospitalized within the past 12 months (66.6 vs. 8.51%, p = 0.003). C. difficile isolation at the time of presentation was not associated with a subsequent disease relapse over a 6-month period in CD (p = 0.557) or UC (p = 0.131).

CONCLUSION

Healthcare exposures remain a significant risk factor for C. difficile isolation in the IBD population; however, this was not associated with relapse of disease. Further studies assessing the clinical significance of C. difficile isolation is warranted in IBD.

Management of inflammatory bowel disease with Clostridium difficile infection

AIM

To address the management of Clostridium difficile (C. difficile) infection (CDI) in the setting of suspected inflammatory bowel disease (IBD)-flare.

METHODS

A systematic search of the Ovid MEDLINE and EMBASE databases by independent reviewers identified 70 articles including a total of 932141 IBD patients or IBD-related hospitalizations.

RESULTS

In those with IBD, CDI is associated with increased morbidity, including subsequent escalation in IBD medical therapy, urgent colectomy and increased hospitalization, as well as excess mortality. Vancomycin-containing regimens are effective first-line therapies for CDI in IBD inpatients. No prospective data exists with regards to the safety or efficacy of initiating or maintaining corticosteroid, immunomodulator, or biologic therapy to treat IBD in the setting of CDI. Corticosteroid use is a risk factor for the development of CDI, while immunomodulators and biologics are not.

CONCLUSION

Strong recommendations regarding when to initiate IBD specific therapy in those with CDI are precluded by a lack of evidence. However, based on expert opinion and observational data, initiation or resumption of immunosuppressive therapy after 48-72 h of targeted antibiotic treatment for CDI may be considered.

Clostridium difficile colitis: A clinical review

BACKGROUND

Clostridium difficile colitis is an important cause of morbidity and mortality in the surgical patient. In recent years, Clostridium difficile infections have shown marked increases in frequency, severity, and resistance to standard treatment. With urgent operative interventions and novel endoscopic approaches, pseudomembranous colitis is being seen more commonly in surgical practices.

DATA SOURCES

In this paper, we will review a number of papers from the literature. We will discuss the epidemiology, evaluation and treatment of Clostridium difficile infection. Fulminant colitis may require emergency operation. For the surgical endoscopist, fecal microbiota transplantation restores the gastrointestinal flora, and has been shown to be effective in more than 80% of patients.

CONCLUSION

Clostridium difficile infection is a major cause of healthcare-related diarrhea leading to increased morbidity and mortality in surgical patients. Increases in failure rates and resistance to current treatments are clinical and economic challenges in the healthcare situation.