Clostridium difficile and inflammatory bowel disease

The incidence and outcomes from Clostridium difficile infection in hospitalized adults with inflammatory bowel disease

OBJECTIVES

Clostridium difficile infection (CDI) may worsen outcomes in patients with inflammatory bowel disease (IBD), but large database-driven studies have conflicting results. The study objective is to analyze clinical features and outcomes in patients with CDI and IBD using the National Hospital Discharge Survey (NHDS) database from 2005 to 2009.

MATERIALS AND METHODS

NHDS collects the clinical information on patients dismissed from non-Federal short-stay United States hospitals. CDI and IBD patients were identified using ICD-9 codes. Demographics, diagnoses, procedures, length of stay (LOS) and dismissal information were abstracted.

RESULTS

Of an estimated 162 million hospitalizations; 5.62 × 10⁵ were for IBD (0.35%); 53.2% were female. CDI developed in 3.7% of hospitalized IBD patients as compared to 0.78% of all adults (OR, 3.9; 95% CI, 3.3-4.6; p < .0001). African-Americans with IBD had a higher likelihood of CDI compared to Caucasians with IBD (OR, 1.67; 95% CI, 1.59-1.75; p < .0001). After adjusting for age, sex and comorbidities, IBD patients with CDI had a longer LOS (mean difference 1 day, p < .0001), higher all-cause, in-hospital mortality (adjusted OR, 4.5; 95% CI, 4.2-4.9; p < .0001), and a higher risk of dismissal to a care facility (adjusted OR, 2.3; 95% CI, 2.2-2.4; p < .0001).

CONCLUSIONS

CDI in IBD patients prolonged hospitalization and increased in-hospital mortality and likelihood of dismissal to a care-facility as compared to IBD patients without CDI. CDI was more common among African-American IBD patients compared to IBD patients of other races.

Clostridium difficile in Inflammatory Bowel Disease: A Retrospective Study

Aim

To investigate the epidemiology and risk factors of Clostridium difficile infections (CDI) in patients with inflammatory bowel disease (IBD).

Methods

This is a retrospective study of patients diagnosed with IBD. 1006 charts were screened and 654 patients met the inclusion criteria. Patients were divided into 2 cohorts based on the presence of prior diagnosis of CDI. Statistical analysis with Pearson's chi-squared and two-sample t-test was performed.

Results

The incidence of CDI among IBD patients was 6.7%. There was equal prevalence of CDI among Crohn's disease (CD) (n = 21, 49%) and ulcerative colitis (UC) (n = 22, 51%). IBD patients acquired CDI at a mean age of 42.7 years, with 56% of infections acquired in the community and only 28% associated with healthcare. Only 30% of IBD patients with CDI had prior antibiotic use, and 16% had prior steroid use. IBD patients were significantly more likely to require biologic therapy (57% versus 37%, p < 0.01) and have extraintestinal manifestations of IBD (43% versus 28%, p < 0.02).

Conclusions

IBD patients are more susceptible to CDI at a younger age and often lack traditional risk factors. IBD patients with at least one CDI were more likely to require biologic therapy and had greater rates of extraintestinal manifestations.

Enteric Infection in Relapse of Inflammatory Bowel Disease: The Utility of Stool Microbial PCR Testing

BACKGROUND

The similar presentations in relapse of inflammatory bowel disease (IBD) and enteric infection pose substantial barriers to diagnosis and treatment. The objective of this study was to investigate the incidence, etiology, predictors, and treatment of enteric infection in patients with IBD.

METHODS

We reviewed the records of 214 patients with IBD who underwent 295 gastrointestinal pathogen panel and Clostridium difficile infection (CDI) polymerase chain reaction (PCR) stool tests during an exacerbation of symptoms. We collected baseline characteristics, PCR outcomes, and medication exposures. We tested for associations via the Chi-square test and the t-test. Logistic regression analysis was used to identify predictors of enteric infection.

RESULTS

Of 295 PCR tests ordered during an exacerbation of symptoms, 38 (12.9%) were positive for CDI and 41 (13.8%) were positive for 14 other pathogens, with E. coli species as the most common. A previous history of CDI or colonic involvement of IBD predicted CDI, whereas a previous colectomy predicted negative testing for CDI. The majority with CDI (24, 63.2%) received oral vancomycin and 15 (37.5%) with other enteric pathogens were treated for their infection. Patients with CDI had a longer median length of hospital stay (8.5 versus 4 days, P = 0.041). Patients who tested negative for enteric infections were more likely to have IBD medications added or up-titrated (P = 0.027).

CONCLUSIONS

Enteric infection was detected in 79 (26.8%) symptomatic patients with IBD , with CDI the most frequent followed by E. coli. Negative stool PCR testing was associated with changes in IBD management. Broad enteric PCR testing should be considered during relapse of IBD.

Optimisation of Intestinal Fibrosis and Survival in the Mouse S. Typhimurium Model for Anti-fibrotic Drug Discovery and Preclinical Applications

BACKGROUND AND AIMS

Intestinal fibrosis is a frequent complication in Crohn's disease [CD]. The mouse Salmonella typhimurium model, due to its simplicity, reproducibility, manipulability, and penetrance, is an established fibrosis model for drug discovery and preclinical trials. However, the severity of fibrosis and mortality are host- and bacterial strain-dependent, thus limiting the original model. We re-evaluated the S. typhimurium model to optimise fibrosis and survival, using commercially available mouse strains.

METHODS

Fibrotic and inflammatory markers were evaluated across S. typhimurium ΔaroA:C57bl/6 studies performed in our laboratory. A model optimisation study was performed using three commercially available mouse strains [CBA/J, DBA/J, and 129S1/SvImJ] infected with either SL1344 or ΔaroA S. typhimurium. Fibrotic penetrance was determined by histopathology, gene expression, and αSMA protein expression. Fibrosis severity, penetrance, and survival were analysed across subsequent CBA studies.

RESULTS

Fibrosis severity and survival are both host- and bacterial strain-dependent. Marked tissue fibrosis and 100% survival occurred in the CBA/J strain infected with SL1344. Subsequent experiments demonstrated that CBA/J mice develop extensive intestinal fibrosis, characterised by transmural tissue fibrosis, a Th1/Th17 cytokine response, and induction of pro-fibrotic genes and extracellular matrix proteins. A meta-analysis of subsequent SL1344:CBA/J studies demonstrated that intestinal fibrosis is consistent and highly penetrant across histological, protein, and gene expression markers. As proof-of-concept, we tested the utility of the SL1344:CBA/J fibrosis model to evaluate efficacy of CCG-203971, a novel anti-fibrotic drug.

CONCLUSION

The S. typhimurium SL1344:CBA/J model is an optimised model for the study of intestinal fibrosis.

Overexpression of the Endosomal Anion/Proton Exchanger ClC-5 Increases Cell Susceptibility toward Clostridium difficile Toxins TcdA and TcdB

Virulent C. difficile toxins TcdA and TcdB invade host intestinal epithelia by endocytosis and use the acidic environment of intracellular vesicles for further processing and activation. We investigated the role of ClC-5, a chloride/proton exchanger expressed in the endosomes of gastrointestinal epithelial cells, in the activation and processing of C. difficile toxins. Enhanced intoxication by TcdA and TcdB was observed in cells expressing ClC-5 but not ClC-4, another chloride/proton exchanger with similar function but different localization. In accordance with the established physiological function of ClC-5, its expression lowered the endosomal pH in HEK293T cells by approximately 0.6 units and enhanced approximately 5-fold the internalization of TcdA. In colon HT29 cells, 34% of internalized TcdA localized to ClC-5-containing vesicles defined by colocalization with Rab5, Rab4a, and Rab7 as early and early-to-late of endosomes but not as Rab11-containing recycling endosomes. Impairing the cellular uptake of TcdA by deleting the toxin CROPs domain did not abolish the effects of ClC-5. In addition, the transport-incompetent mutant ClC-5 E268Q similarly enhanced both endosomal acidification and intoxication by TcdA but facilitated the internalization of the toxin to a lower extent. These data suggest that ClC-5 enhances the cytotoxic action of C. difficile toxins by accelerating the acidification and maturation of vesicles of the early and early-to-late endosomal system. The dispensable role of electrogenic ion transport suggests that the voltage-dependent nonlinear capacitances of mammalian CLC transporters serve important physiological functions. Our data shed light on the intersection between the endocytotic cascade of host epithelial cells and the internalization pathway of the large virulence C. difficile toxins. Identifying ClC-5 as a potential specific host ion transporter hijacked by toxins produced by pathogenic bacteria widens the horizon of possibilities for novel therapies of life-threatening gastrointestinal infections.

Management of Clostridium difficile Infection in Inflammatory Bowel Disease: Expert Review from the Clinical Practice Updates Committee of the AGA Institute

The purpose of this expert review is to synthesize the existing evidence on the management of Clostridium difficile infection in patients with underlying inflammatory bowel disease. The evidence reviewed in this article is a summation of relevant scientific publications, expert opinion statements, and current practice guidelines. This review is a summary of expert opinion in the field without a formal systematic review of evidence. Best Practice Advice 1: Clinicians should test patients who present with a flare of underlying inflammatory bowel disease for Clostridium difficile infection. Best Practice Advice 2: Clinicians should screen for recurrent C difficile infection if diarrhea or other symptoms of colitis persist or return after antibiotic treatment for C difficile infection. Best Practice Advice 3: Clinicians should consider treating C difficile infection in inflammatory bowel disease patients with vancomycin instead of metronidazole. Best Practice Advice 4: Clinicians strongly should consider hospitalization for close monitoring and aggressive management for inflammatory bowel disease patients with C difficile infection who have profuse diarrhea, severe abdominal pain, a markedly increased peripheral blood leukocyte count, or other evidence of sepsis. Best Practice Advice 5: Clinicians may postpone escalation of steroids and other immunosuppression agents during acute C difficile infection until therapy for C difficile infection has been initiated. However, the decision to withhold or continue immunosuppression in inflammatory bowel disease patients with C difficile infection should be individualized because there is insufficient existing robust literature on which to develop firm recommendations. Best Practice Advice 6: Clinicians should offer a referral for fecal microbiota transplantation to inflammatory bowel disease patients with recurrent C difficile infection.

Therapeutic modulation of gut microbiota in inflammatory bowel disease: More questions to be answered

Patients with inflammatory bowel disease (IBD) exhibit impaired control of the microbiome in the gut, and 'dysbiosis' is commonly observed. Western diet is a risk factor for the development of IBD, but it may have different effects on gut microbiota between IBD and non-IBD individuals. Exclusive enteral nutrition (EEN) can induce remission in pediatric Crohn's disease with a decrease in gut microbial diversity. Although there are some theoretical benefits, actual treatment effects of prebiotics and probiotics in IBD vary. High-quality studies have shown that VSL#3 (a high-potency probiotic medical food containing eight different strains) exhibits benefits in treating ulcerative colitis, and gut microbial diversity is reduced after treated with VSL#3 in animal models. The effect of fecal microbiome transplantation on IBD is controversial. Increasing microbial diversity compared with impaired handling of bacteria presents a dilemma. Antibiotics are the strongest factors in the reduction of microbiome ecological diversity. Some antibiotics may help to induce remission of the disease. Microbiome alteration has been suggested to be an intrinsic property of IBD and a potential predictor in diagnosis and prognosis. However, the effects of therapeutic modulations are variable; thus, more questions remain to be answered.

The Use and Efficacy of Fecal Microbiota Transplantation for Refractory Clostridium difficile in Patients with Inflammatory Bowel Disease

Clostridium difficile (CD) is an anaerobic, spore-forming bacillus that is responsible for a spectrum of gastrointestinal illness ranging from asymptomatic carriage to toxic megacolon and death. The prevalence of CD infection is increasing in both hospitalized and community-based inflammatory bowel disease populations. Standard antibiotic therapy fails to cure or prevent recurrence in more than 50% of patients, thus increasing the need for alternative therapies. Recently, fecal microbiota transplantation has received renewed attention as a therapy for refractory or recurrent CD infection. A high success rate combined with a favorable safety profile makes this therapy an attractive option for patients who have failed standard antibiotic therapy. Increasingly, this therapy is used in patients with CD infection and inflammatory bowel disease, as the combination of active inflammation and toxin-producing CD provides a challenging mix for clinicians.

Expression of Treg/Th17 cells as well as related cytokines in patients with inflammatory bowel disease

OBJECTIVE

To investigate the expressions of peripheral regulatory T cells (Treg) and T helper cells (Th17) as well as related cytokines in peripheral blood of patients with inflammatory bowel disease (IBD).

METHODS

One hundred four cases of IBD patients admitted in our hospital were selected for this study. One hundred cases of people receiving healthy physical examination were included in the control group in the corresponding period. The levels of CD4⁺CD25⁺Treg and Th17 subsets were analyzed in peripheral blood of two groups using flow cytometry. The expressions of IL-10, TGF-β1, IL-17 and IL-23 mRNA and protein were detected using real-time fluorescence quantitative PCR and ELISA.

RESULTS

Compared with the control group, the proportion of Treg in peripheral blood was decreased significantly in observation group (P<0.05), the proportion of Th17 cells was increased significantly (P<0.05), and Treg/Th17 was decreased significantly (P<0.05). Compared with the control group, the expressions of IL-10 and TGF-β1 mRNA and protein in peripheral blood of patients were significantly down-regulated in observation group, while the expressions of Th17 cytokines IL-17 and IL-23 mRNA and protein were significantly increased (P<0.05).

CONCLUSION

The proportion of Th17 and increased cytokine level suggested the inflammatory level was higher in IBD patients. The down regulations of Treg and cytokine suggested that the immunosuppression function was down-regulated in IBD patients, and the disproportionality might be one of the mechanisms of IBD.

Review article: acute severe ulcerative colitis - evidence-based consensus statements

BACKGROUND

Acute severe ulcerative colitis (ASUC) is a potentially life-threatening complication of ulcerative colitis.

AIM

To develop consensus statements based on a systematic review of the literature of the management of ASUC to improve patient outcome.

METHODS

Following a literature review, the Delphi method was used to develop the consensus statements. A steering committee, based in Australia, generated the statements of interest. Three rounds of anonymous voting were carried out to achieve the final results. Acceptance of statements was pre-determined by ≥80% votes in 'complete agreement' or 'agreement with minor reservation'.

RESULTS

Key recommendations include that patients with ASUC should be: hospitalised, undergo unprepared flexible sigmoidoscopy to assess severity and to exclude cytomegalovirus colitis, and be provided with venous thromboembolism prophylaxis and intravenous hydrocortisone 100 mg three or four times daily with close monitoring by a multidisciplinary team. Rescue therapy such as infliximab or ciclosporin should be started if insufficient response by day 3, and colectomy considered if no response to 7 days of rescue therapy or earlier if deterioration. With such an approach, it is expected that colectomy rate during admission will be below 30% and mortality less than 1% in specialist centres.

CONCLUSION

These evidenced-based consensus statements on acute severe ulcerative colitis, developed by a multidisciplinary group, provide up-to-date best practice recommendations that improve and harmonise management as well as provide auditable quality assessments.

Peri-transplant clostridium difficile infections in patients undergoing allogeneic hematopoietic progenitor cell transplant

Clostridium difficile infections (CDI) remain the leading cause of infectious diarrhea among hospitalized patients in this country. Patients with hematologic malignancies, especially those who undergo hematopoietic progenitor cell transplants are particularly at risk for developing CDI. One hundred and forty seven consecutive allogeneic hematopoietic progenitor cell transplants were analyzed for peri-transplant Clostridium difficile infections (PT-CDI). Sixteen patients (11%) developed PT-CDI (Median time = 7 days after transplant). The probability for developing PT-CDI during the peri-transplant period was 12.3%. History of CDI was strongly associated with the development of PT-CDI (P = 0.008) (OR = 5.48) (P = 0.017). These patients also developed PT-CDI much earlier than in those without a history (median 1 day vs. 8 days, P = 0.03). The probability for developing PT-CDI for those with a history was 39%. There was a trend toward significance (P = 0.065) between matched related donor grafts and the development of PT-CDI (OR = 0.245) (P = 0.08). Age, sex, diagnosis, transplant preparative regimens, Graft-versus-host disease (GVHD) prophylaxis, grade 3/4 acute GVHD, or use of antimicrobials within 8 weeks of transplant were not associated with PT-CDI. Non-CDI-related deaths occurred in one patient in the PT-CDI group and nine in the group without PT-CDI. In the remaining 139 patients, the length of hospital stay for those with PT-CDI was significantly longer than those without (mean 27 days vs. 22 days; P = 0.02).

Clostridium difficile Infection: A Rarity in Patients Receiving Chronic Antibiotic Treatment for Crohn's Disease

BACKGROUND

Prolonged antibiotic use is limited by several adverse effects, one of which is Clostridium difficile infection (CDI). The aim of this study was to determine the incidence of CDI in patients receiving chronic antibiotic treatment for Crohn's disease (CD).

METHODS

We conducted a retrospective review of 100 patients with CD for which ≥6 months of outpatient antibiotic therapy was prescribed. Data were collected regarding demographics, CD phenotype, treatment history, and CDI. The incidence of CDI in our patient population was calculated and compared with historical controls.

RESULTS

100 patients were studied-60% of men, mean age 23.9 years at CD diagnosis. Eighty-two percent had disease involving the ileum, and 33% had disease involving the colon. The mean duration of antibiotic therapy was 39.6 months (range, 6-217 months). The most commonly prescribed classes of antibiotics were fluoroquinolones (84%), penicillins (57%), and cephalosporins (32%). Forty-nine percent of patients were treated with concomitant thiopurines, 45% with budesonide, and 41% with biologics. The overall incidence of CDI was 2%. This incidence of CDI was lower than previously reported for non-CD patients receiving chronic antibiotics for continuous-flow left ventricular assist device infections (12.5%) and orthopedic prosthesis infections (22.2%).

CONCLUSIONS

The incidence of CDI is rare in patients receiving chronic antibiotic treatment for CD, and it seems significantly lower than for non-CD populations reported in the literature.

Faecal microbiota transplantation-A clinical view

Faecal microbiota transplantation has gained increasing attention over the last decade as various phenotypes could be transferred from a donor to a recipient in different animal models. Clinically, however, the sole indication with evidence from a randomized placebo controlled trial is refractory Clostridium difficile infection. Despite revealing successful clinical outcomes, questions concerning regulatory affairs, the identification of the best donor, the optimal mixture of the transplant as well as the preferred route of administration remain to be clarified even for this indication. Initiated by the idea that alterations in the composition of the intestinal microbiota are associated with intestinal inflammation in inflammatory bowel disease, several studies investigated whether faecal microbiota transplantation would be an equally suitable approach for these devastating disorders. Indeed, the available data indicate changes in the microbiota composition following faecal microbial transplantation depending on the degree of intestinal inflammation. Furthermore, first data even provide evidence that the transplantation of an "optimized" microbiota induces clinical remission in ulcerative colitis. However, despite these intriguing results it needs to be considered that not only "a cure of inflammation", but also risk factors and phenotypes including obesity can be transferred via faecal microbiota transplantation. Thus, a deeper understanding of the impact of a distinct microbiota composition is required before "designing" the optimal faecal microbiota transplant.

Fulminant Clostridium difficile enteritis causing abdominal compartment syndrome

INTRODUCTION

Clostridium difficile infection of the small bowel, or C. difficile enteritis (CDE), is an uncommon condition. Cases reported previously have been described in patients with inflammatory bowel disease (IBD), compromised immune systems, or a history of colectomy or small bowel surgery.

CASE DESCRIPTION

We present a case of fulminant CDE causing abdominal compartment syndrome following a routine outpatient inguinal hernia repair. This patient developed multiple organ failure dysfunction syndrome requiring surgical abdominal decompression and a small bowel resection. This case highlights the challenges in the diagnosis of CDE, particularly in patients with intact colons and unusual presentations.

DISCUSSION

A high index of suspicion is required, as early recognition of CDE is essential in reducing morbidity and mortality. This case report is followed by a review of the current literature on CDE, with a focus on the complexities inherent in the identification of this problem and the decision-making process for surgical intervention.

Surgical and medical treatment in patients with acute severe ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory disease of the mucosa of the colorectum. The treatment of UC depends on the severity of symptoms and the extent of the disease. Acute severe colitis (ASC) occurs in 12-25% of patients with UC. Patients with ASC must be managed by a multidisciplinary team. Medically or surgically aggressive treatment is carried out with the final aim of reducing mortality. Intravenous administration of corticosteroids is the mainstay of the therapy. Medical rescue therapy based on cyclosporine or infliximab should be considered if there is no response to corticosteroids for 3 days. If there has been no response to medical rescue therapy after 4-7 days, the patient must undergo colectomy in emergency surgery. Prolonged observation is counterproductive, as over time it increases the risk of toxic megacolon and perforation, with a very high mortality rate. The best potential treatment is subtotal colectomy with ileostomy and preservation of the rectum. Emergency surgery in UC should not be seen as a last chance, but can be considered as a life-saving procedure. Colectomies in emergency setting are characterized by high morbidity rates but the mortality is low.

Infections and Chronic Inflammatory Bowel Disease

In the more recent years since the introduction of anti-TNF therapy, the treatment strategy in chronic inflammatory bowel disease has developed more towards an early intensive, often double immunosuppression. While this leads to an improved therapeutic success, this intensified therapy also increases the risk for side effects and especially for infectious complications. The early detection of this complication in the immunocompromised patient is often more difficult due to the potential broad spectrum of infectious agents, the often atypical presentation in conjunction with the immunosuppression as well as often similar symptoms regarding intestinal infectious complications common for a flare of the underlying disease. In the first part, this overview will discuss the broad spectrum of potential infectious complications, using pulmonary infections as an example and presenting an algorithm for detection and therapy. In the second part, common intestinal infectious complications will be discussed from diagnosis to therapy.

Clostridium difficile infection in Chilean patients submitted to hematopoietic stem cell transplantation

Introduction

Patients submitted to hematopoietic stem cell transplantation have an increased risk of Clostridium difficile infection and multiple risk factors have been identified. Published reports have indicated an incidence from 9% to 30% of transplant patients however to date there is no information about infection in these patients in Chile.

Methods

A retrospective analysis was performed of patients who developed C. difficile infection after hematopoietic stem cell transplantations from 2000 to 2013. Statistical analysis used the Statistical Package for the Social Sciences software.

Results

Two hundred and fifty patients were studied (mean age: 39 years; range: 17–69), with 147 (59%) receiving allogeneic transplants and 103 (41%) receiving autologous transplants. One hundred and ninety-two (77%) patients had diarrhea, with 25 (10%) cases of C. difficile infection being confirmed. Twenty infected patients had undergone allogeneic transplants, of which ten had acute lymphoblastic leukemia, three had acute myeloid leukemia and seven had other diseases (myelodysplastic syndrome, chronic myeloid leukemia, severe aplastic anemia). In the autologous transplant group, five patients had C. difficile infection; two had multiple myeloma, one had amyloidosis, one had acute myeloid leukemia and one had germinal carcinoma. The overall incidence of C. difficile infection was 4% within the first week, 6.4% in the first month and 10% in one year, with no difference in overall survival between infected and non-infected groups (72.0% vs. 67.6%, respectively; p-value = 0.56). Patients infected after allogeneic transplants had a slower time to neutrophil engraftment compared to non-infected patients (17.5 vs. 14.9 days, respectively; p-value = 0.008). In the autologous transplant group there was no significant difference in the neutrophil engraftment time between infected and non-infected patients (12.5 days vs. 11.8 days, respectively; p-value = 0.71). In the allogeneic transplant group, the median time to acute graft-versus-host disease was similar between the two groups (p-value = 0.08), as was the incidence of grades 1–4 acute graft-versus-host disease (40% vs. 48%; p-value >0.05).

Conclusion

The incidence of C. difficile infection after hematopoietic stem cell transplantation was low, with a significant number of cases occurring shortly after transplantation. Allogeneic transplants had a three-time higher risk of infection compared to autologous transplants, but this was not associated with increased mortality, decreased overall survival or higher risk of acute graft-versus-host disease.

Association of tcdA+/tcdB+ Clostridium difficile Genotype with Emergence of Multidrug-Resistant Strains Conferring Metronidazole Resistant Phenotype

Background:

Reduced susceptibility of Clostridium difficile to antibiotics is problematic in clinical settings. There is new evidence indicating the cotransfer of toxin-encoding genes and conjugative transposons encoding resistance to antibiotics among different C. difficile strains. To analyze this association, in the current study, we evaluated the frequency of toxigenic C. difficile among the strains with different multidrug-resistant (MDR) profiles in Iran.

Methods:

Antimicrobial susceptibility patterns and minimal inhibitory concentrations (MIC) of the isolates were determined against metronidazole, imipenem, ceftazidime, amikacin, and ciprofloxacin by agar dilution method. The association of the resistance profiles and toxigenicity of the strains were studied by PCR targeting tcdA and tcdB genes.

Results:

Among 86 characterized strains, the highest and lowest resistance rates were related to ciprofloxacin (97%) and metronidazole (5%), respectively. The frequency of resistance to other antibiotics was as follow: imipenem (48%), ceftazidime (76%), and amikacin (76.5%). Among the resistant strains, double drug resistance and MDR phenotypes were detected in the frequencies of 10.4% and 66.2%, respectively. All of the metronidazole-resistant strains belonged to tcdA ⁺/tcdB ⁺ genotype with triple or quintuple drug resistance phenotypes. MIC₅₀ and MIC₉₀ for this antibiotic was equally ≤ 8 μg/ml.

Conclusion:

These results proposed the association of tcdA ⁺/tcdB ⁺ genotype of C. difficile and the emergence of resistance strains to broad-spectrum antibiotics and metronidazole.

Clostridium difficile infection among hospitalized HIV-infected individuals: epidemiology and risk factors: results from a case-control study (2002-2013)

Background

HIV infection is a risk factor for Clostridium difficile infection (CDI) yet the immune deficiency predisposing to CDI is not well understood, despite an increasing incidence of CDI among such individuals. We aimed to estimate the incidence and to evaluate the risk factors of CDI among an HIV cohort in Italy.

Methods

We conducted a retrospective case-control (1:2) study. Clinical records of HIV inpatients admitted to the National Institute for Infectious Disease “L. Spallanzani”, Rome, were reviewed (2002-2013). Cases: HIV inpatients with HO-HCFA CDI, and controls: HIV inpatients without CDI, were matched by gender and age. Logistic regression was used to identify risk factors associated with CDI.

Results

We found 79 CDI episodes (5.1 per 1000 HIV hospital admissions, 3.4 per 10000 HIV patient-days). The mean age of cases was 46 years. At univariate analysis factors associated with CDI included: antimycobacterial drug exposure, treatment for Pneumocystis pneumonia, acid suppressant exposure, previous hospitalization, antibiotic exposure, low CD4 cell count, high Charlson score, low creatinine, low albumin and low gammaglobulin level. Using multivariate analysis, lower gammaglobulin level and low serum albumin at admission were independently associated with CDI among HIV-infected patients.

Conclusions

Low gammaglobulin and low albumin levels at admission are associated with an increased risk of developing CDI. A deficiency in humoral immunity appears to play a major role in the development of CDI. The potential protective role of albumin warrants further investigation.

Identification of toxemia in patients with Clostridium difficile infection

Toxemia can develop in Clostridium difficile-infected animals, and correlates with severe and fulminant disease outcomes. Circumstantial evidence suggests that toxemia may occur in patients with C. difficile infection (CDI), but positive diagnosis is extremely rare. We analyzed the potential for C. difficile toxemia in patients, determined its characteristics, and assessed challenges. C. difficile toxins in serum from patients were tested using an ultrasensitive cell-based assay and further confirmed by Rac1 glucosylation assay. The factors that hinder a diagnosis of toxemia were assessed, including investigation of toxin stability, the level of toxins-specific neutralizing antibodies in sera and its effect on diagnosis limits. CDI patients develop detectable toxemia in some cases (2.3%). Toxins were relatively stable in stored sera. Neutralizing anti-toxin antibodies were present during infection and positively correlated with the diagnosis limits. Thus, the masking effect of toxin-specific neutralizing antibodies is the major obstacle in diagnosing C. difficile toxemia using cell-based bioassays.

Fecal microbiota transplantation (FMT) for Clostridium difficile infection: focus on immunocompromised patients

Clostridium difficile infection (CDI) is an emerging problem worldwide associated with significant morbidity, mortality, recurrence rates and healthcare costs. Immunosuppressed patients, including HIV-seropositive individuals, solid organ transplant recipients, patients with malignancies, hematopoietic stem cell transplant recipients, and patients with inflammatory bowel disease are increasingly recognized as being at higher risk of developing CDI where it may be associated with significant complications, recurrence, and mortality. Fecal microbiota transplantation (FMT) has proven to be an effective and safe procedure for the treatment of recurrent or refractory CDI in immunocompetent patients by restoring the gut microbiota and resistance to further recurrences. During the last two years the first data on FMT in immunocompromised patients began to appear in the medical literature. Herein we summarize the use of FMT for the treatment of CDI with a focus on immunocompromised patients.

[Characterization, influence and manipulation of the gastrointestinal microbiota in health and disease]

The gastrointestinal tract harbors trillions of microorganisms that are indispensable for health. The gastrointestinal microbiota can be studied using culture and molecular methods. The applications of massive sequencing are constantly increasing, due to their high yield, increasingly accessible costs, and the availability of free software for data analysis. The present article provides a detailed review of a large number of studies on the gastrointestinal microbiota and its influence on human health; particular emphasis is placed on the evidence suggesting a relationship between the gastrointestinal microbial ecosystem and diverse physiological and immune/inflammatory processes. Discussion of the articles analyzed combines a medical approach and current concepts of microbial molecular ecology. The present revision aims to be useful to those interested in the gastrointestinal microbiota and its possible alteration to maintain, re-establish and enhance health in the human host.

Testing for Clostridium difficile in patients newly diagnosed with inflammatory bowel disease in a community setting

BACKGROUND

The incidence of Clostridium difficile infection (CDI) in inflammatory bowel disease (IBD) is increasing, and CDI has a negative impact on IBD outcomes with both increased morbidity and mortality. Data are lacking regarding the rate of appropriate testing for CDI at the time of diagnosis.

METHODS

We sought to determine the rate of CDI testing and CDI positivity at diagnosis of IBD using data collected through the Ocean State Crohn's and Colitis Area Registry (OSCCAR), a prospective cohort of patients with newly diagnosed IBD. CDI testing and CDI positivity were determined by reviewing the medical records of patients enrolled into the registry and diagnosed with IBD between January 2008 and July 2011.

RESULTS

Of 320 enrolled patients, 227 (70.9%) reported diarrhea, and CDI testing was performed for 113 (49.8%) of the 227 patients. CDI testing was not recorded as being performed for the remaining 114 patients who reported having diarrhea. An additional 24 patients were tested for CDI but did not report having diarrhea. Seven (5.1%) of the 137 patients tested for CDI were positive.

CONCLUSIONS

Testing for CDI is significantly lower than expected at diagnosis of IBD. Although the prevalence of CDI among tested patients is approximately 5%, a low testing rate suggests a significant quality issue in the diagnosis of IBD, with the potential for delayed diagnosis of CDI.

Clostridium difficile infection aggravates colitis in interleukin 10-deficient mice

AIM: To investigate the effect of Clostridium difficile (C. difficile) infection in an interleukin 10-deficient (IL-10^-/-) mouse model of inflammatory bowel disease.

METHODS: Bone marrow-derived dendritic cells isolated from wild type (WT) and IL-10^-/-mice were stimulated for 4 h with C. difficile toxin A (200 μg/mL), and gene expression of interferon (IFN)-γ, IL-12 and IL-23 was determined by real-time reverse transcription polymerase chain reaction. WT and IL-10^-/- mice (n = 20 each) were exposed to an antibiotic cocktail for three days and then were injected with clindamycin (i.p.). Mice (n = 10 WT, 10 IL-10^-/-) were then challenged with oral administration of C. difficile (1 × 10⁵ colony forming units of strain VPI 10463). Animals were monitored daily for 7 d for signs of colitis. Colonic tissue samples were evaluated for cytokine gene expression and histopathologic analysis.

RESULTS: C. difficile toxin A treatment induced IFN-γ gene expression to a level that was significantly higher in BDMCs from IL-10^-/- compared to those from WT mice (P < 0.05). However, expression of IL-12 and IL-23 was not different among the groups. Following C. difficile administration, mice developed diarrhea and lost weight within 2-3 d. Weight loss was significantly greater in IL-10^-/- compared to WT mice (P < 0.05). C. difficile infection induced histopathologic features typical of colitis in both IL-10^-/- and WT mice. The histopathologic severity score was significantly higher in the IL-10^-/- than in WT mice (mean ± standard error; 5.50 ± 0.53 vs 2.44 ± 0.46; P < 0.05). This was accompanied by a significantly greater increase in IFN-γ gene expression in colonic tissues from IL-10^-/- than from WT mice challenged with C. difficile (P < 0.05).

CONCLUSION: These results indicate that colitis is more severe after C. difficile infection in IL-10^-/-mice, and that IFN-γ expression is involved in this process.

Role of the intestinal microbiota and fecal transplantation in inflammatory bowel diseases

Ulcerative colitis and Crohn's disease are the two major types of inflammatory bowel disease (IBD). Despite intensive study, it is still challenging because the precise etiology and pathogenesis remains unclear. Studies have shown that IBD is associated with changes in the composition of intestinal microbiota, as either a cause or a consequence of abnormal host immune response in genetic susceptible population. Two specific microorganisms (Mycobacterium avium subsp. paratuberculosis and Escherichia coli) get more widely studied, but till now no single microorganism has been identified as the only pathogen. Genetic susceptibility data also suggest impaired handling of bacteria as well as an improper immune response to potential pathogens. The microbiota provides new therapeutic methods, and fecal microbiota transplantation may restore the balance of intestinal flora to supplement or optimize the current therapies.

Management of acute severe ulcerative colitis

The management strategy of acute severe ulcerative colitis has evolved over the past decade from being entirely restricted to twin choices of intravenous steroids or colectomy to include colon rescue therapies like cyclosporin as well as infliximab. However it still remains a medical emergency requiring hospitalization and requires care from a multidisciplinary team comprising of a gastroenterologist and a colorectal surgeon. The frame shift in management has been the emphasis on time bound decision making with an attempt to curtail the mortality rate to below 1%. Intravenous corticosteroids are the mainstay of therapy. Response to steroids should be assessed at day 3 of admission and partial/non-responders should be considered for alternative medical therapy/surgery. Medical rescue therapies include intravenous cyclosporin and infliximab. Cyclosporin is administered in a dose of 2 mg/kg per day and infliximab is administered as a single dose intravenous infusion of 5 mg/kg. Approximately 75% patients have short term and 50% patients have long term response to cyclosporin. Long term response to cyclosporin is improved in patients who are thiopurine naïve and are started on thiopurines on day 7. Infliximab also has a response rate of approximately 70% in short term and 50% in long term. Both cyclosporin and infliximab are equally efficacious medical rescue therapies as demonstrated in a recent randomized control trial. Patients not responding to infliximab or cyclosporin should be considered for colectomy.

Serum bacterial toxins are related to the progression of inflammatory bowel disease

OBJECTIVES

Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is an autoimmune disease. Disorder of intestinal microbes is thought to play a critical role in the pathogenesis of IBD. Detection of bacterial toxins could become a new approach to judge the situation of this disease.

MATERIALS AND METHODS

Serum samples were collected from 142 IBD patients and 40 healthy donors as well as 15 CD patients with anti-tumor necrosis factor (TNF) monoclonal antibody (infliximab [IFX]). Enzyme-linked immunosorbent assay kits for Clostridium difficile, Escherichia coli O157, salmonella, and Staphylococcus aureus were used to analyze these bacterial toxins in sera.

RESULTS

The positive rates of bacterial toxins from C. difficile, E. coli O157, salmonella, and S. aureus in the IBD patients were found in low incidences and associated with disease duration, colonic involvement, and treatment with prednisone and immunomodulators. The active CD and UC patients had significant higher positive rates of these bacterial toxins than those in remission or healthy controls. Blockage of TNF with IFX in CD patients resulted in significant decreases of the levels of toxins of C. difficile, E. coli O157, salmonella, and S. aureus in sera.

CONCLUSIONS

Some bacterial toxins are present in the sera of active IBD patients, and patients with long disease duration, colonic involvement, or treatment with prednisone and immunomodulators are more susceptible to bacterial infection. Inhibition of inflammation with IFX would reduce the bacterial toxins via improvement of intestinal inflammation. Detecting bacteria-derived toxins in sera can be used to predict the progression of IBD.

Clostridium difficile infection in patients with inflammatory bowel disease

Clostridium difficile is a bacterium widely distributed in the human environment. In the last decade the incidence and severity of Clostridium difficile infection has grown, particularly in Europe and North America, making it one of the more common nosocomial infections. A group particularly susceptible to Clostridium difficile infection are patients with inflammatory bowel disease, especially those with involvement of the colon. This paper presents relevant data on Clostridium difficile infections in inflammatory bowel disease patients, including epidemiology, pathogenesis, diagnosis and treatment.

Role of the microbiota in immunity and inflammation

The microbiota plays a fundamental role on the induction, training, and function of the host immune system. In return, the immune system has largely evolved as a means to maintain the symbiotic relationship of the host with these highly diverse and evolving microbes. When operating optimally, this immune system-microbiota alliance allows the induction of protective responses to pathogens and the maintenance of regulatory pathways involved in the maintenance of tolerance to innocuous antigens. However, in high-income countries, overuse of antibiotics, changes in diet, and elimination of constitutive partners, such as nematodes, may have selected for a microbiota that lack the resilience and diversity required to establish balanced immune responses. This phenomenon is proposed to account for some of the dramatic rise in autoimmune and inflammatory disorders in parts of the world where our symbiotic relationship with the microbiota has been the most affected.

Case-control study of factors that trigger inflammatory bowel disease flares

AIM: To explore the association between inflammatory bowel diseases (IBD) flares and potential triggers.

METHODS: Patients evaluated for an acute flare of IBD by a gastroenterologist at the Dallas VA Medical Center were invited to participate, as were a control group of patients with IBD in remission. Patients were systematically queried about nonsteroidal anti-inflammatory drug use, antibiotic use, stressful life events, cigarette smoking, medication adherence, infections, and travel in the preceding 3 mo. Disease activity scores were calculated for each patient at the time of enrollment and each patient’s chart was reviewed. Multivariate regression analysis was performed.

RESULTS: A total of 134 patients with IBD (63 with Crohn’s disease, 70 with ulcerative colitis, and 1 with indeterminate colitis) were enrolled; 66 patients had flares of their IBD and 68 were controls with IBD in remission (for Crohn’s patients, average Crohn’s disease activity index was 350 for flares vs 69 in the controls; for UC patients, Mayo score was 7.6 for flares vs 1 for controls in those with full Mayo available and 5.4p for flares vs 0.1p for controls in those with partial Mayo score). Only medication non-adherence was significantly more frequent in the flare group than in the control group (48.5% vs 29.4%, P = 0.03) and remained significant on multivariate analysis (OR = 2.86, 95%CI: 1.33-6.18). On multivariate regression analysis, immunomodulator use was found to be associated with significantly lower rates of flare (OR = 0.40, 95%CI: 0.19-0.86).

CONCLUSION: In a study of potential triggers for IBD flares, medication non-adherence was significantly associated with flares. These findings are incentive to improve medication adherence.

Enterotoxigenic Clostridium perfringens infection and pediatric patients with inflammatory bowel disease

BACKGROUND AND AIMS

Clostridium difficile is the major cause of antibiotic-associated diarrhea and is the most well known bacterial pathogen associated with inflammatory bowel disease (IBD). Enterotoxigenic Clostridium perfringens has also been detected in up to 15% of antibiotic-associated diarrhea cases, and it has not been found in healthy people. The aim of this study was to investigate the prevalence of C. perfringens infection in pediatric patients with IBD.

METHODS

This was a prospective, controlled study evaluating pediatric IBD patients in the Department of Pediatric Gastroenterology and Nutrition in Warsaw, Poland. All of the patients were diagnosed according to the Porto criteria. There were two control groups: (1) non-IBD patients that were suspected for bacterial diarrhea and (2) healthy children. Stool samples were collected on the day of admission. C. perfringens infection diagnosis was based on a positive stool enzyme immunoassay (C. perfringens enterotoxin test kit TechLab).

RESULTS

91 fecal specimens from patients with IBD were collected. The average patient age was 11.7 years in IBD group, 7.4 years in non-IBD patients with diarrhea, and 7.4 years in healthy children. The prevalence of C. perfringens infection was 9% (8/91; CI 95% 4.6-16.4). There were more Crohn's patients (6/8) in the C. perfringens positive group. There was no C. perfringens infection in the two control groups.

CONCLUSION

Our pilot data add evidence to the hypothesis that Clostridia other than C. difficile may play a significant role in the clinical course of IBD. However, further studies are needed to confirm this.

Community-acquired Clostridium difficile infection: an increasing public health threat

There has been a startling shift in the epidemiology of Clostridium difficile infection over the last decade worldwide, and it is now increasingly recognized as a cause of diarrhea in the community. Classically considered a hospital-acquired infection, it has now emerged in populations previously considered to be low-risk and lacking the traditional risk factors for C. difficile infection, such as increased age, hospitalization, and antibiotic exposure. Recent studies have demonstrated great genetic diversity for C. difficile, pointing toward diverse sources and a fluid genome. Environmental sources like food, water, and animals may play an important role in these infections, apart from the role symptomatic patients and asymptomatic carriers play in spore dispersal. Prospective strain typing using highly discriminatory techniques is a possible way to explore the suspected diverse sources of C. difficile infection in the community. Patients with community-acquired C. difficile infection do not necessarily have a good outcome and clinicians should be aware of factors that predict worse outcomes in order to prevent them. This article summarizes the emerging epidemiology, risk factors, and outcomes for community-acquired C. difficile infection.

Clostridium difficile enteritis: a new role for an old foe

BACKGROUND

Small bowel involvement of Clostridium difficile is increasingly encountered. Data on many management aspects are lacking.

AIM

To synthesis existing reports and assess the frequency, pathophysiology, outcomes, risk factors, diagnosis and management of C. difficle enteritis.

METHODS

A systematic review of the literature was conducted to evaluate evidence regarding frequency, pathophysiology, risk factors, optimal diagnosis, management and outcomes for C. difficle enteritis. Three major databases (PubMed, MEDLINE and the Cochrane Library) were searched. The review included original articles reporting C. difficle enteritis from January 1950 to December 2012.

RESULTS

C. difficle enteritis is rare but increasingly encountered. Presentation is variable and distinct predisposing factors include emergency surgery, white race and increased age. Diagnosis generally involves a sensitive but often non specific screening test for C. difficile antigens. Oral metronidazole represents first line therapy and surgery may be required for complications. Outcomes are inconsistent but may be improving.

CONCLUSIONS

A high index of clinical suspicion, early diagnosis and treatment are vital. Further prospective studies are needed to determine the significance of asymptomatic small bowel C. difficile infections.

Histologic findings and clinical characteristics in acutely symptomatic ulcerative colitis patients with superimposed Clostridium difficile infection

OBJECTIVES

To examine biopsy specimens for histologic features suggestive of Clostridium difficile infection in patients with ulcerative colitis (UC).

METHODS

Nine patients with UC had colonic biopsy specimens taken during a symptomatic flare that coincided with positive C difficile (C difficile+) tests. Twenty-eight controls were biopsied during a UC flare but tested negative for C difficile. We reviewed the slides for evidence of pseudomembranes, ischemic-like changes, degree of colitis, and lamina propria hemorrhage.

RESULTS

In C difficile+ patients, 4 (44.4%) of 9 had microscopic pseudomembranes compared with 11% in controls (P < .05). Other histologic/clinical features were not predictive.

CONCLUSIONS

Although the presence of microscopic pseudomembranes suggests C difficile infection in patients with UC, sensitivity and specificity are poor; biopsy findings do not reliably detect this infection in patients with UC.

Clostridium difficile and inflammatory bowel disease: Role in pathogenesis and implications in treatment

Clostridium difficile (C. difficile) is the leading cause of antibiotic associated colitis and nosocomial diarrhea. Patients with inflammatory bowel disease (IBD) are at increased risk of developing C. difficile infection (CDI), have worse outcomes of CDI-including higher rates of colectomy and death, and experience higher rates of recurrence. However, it is still not clear whether C. difficile is a cause of IBD or a consequence of the inflammatory state in the intestinal environment. The burden of CDI has increased dramatically over the past decade, with severe outbreaks described in many countries, which have been attributed to a new and more virulent strain. A parallel rise in the incidence of CDI has been noted in patients with IBD. IBD patients with CDI tend be younger, have less prior antibiotic exposure, and most cases of CDI in these patients represent outpatient acquired infections. The clinical presentation of CDI in these patients can be unique-including diversion colitis, enteritis and pouchitis, and typical findings on colonoscopy are often absent. Due to the high prevalence of CDI in patients hospitalized with an IBD exacerbation, and the prognostic implications of CDI in these patients, it is recommended to test all IBD patients hospitalized with a disease flare for C. difficile. Treatment includes general measures such as supportive care and infection control measures. Antibiotic therapy with either oral metronidazole, vancomycin, or the novel antibiotic-fidaxomicin, should be initiated as soon as possible. Fecal macrobiota transplantation constitutes another optional treatment for severe/recurrent CDI. The aim of this paper is to review recent data on CDI in IBD: role in pathogenesis, diagnostic methods, optional treatments, and outcomes of these patients.

Overview of Clostridium difficile infection: implications for China

The incidence and severity of Clostridium difficile infection (CDI) have dramatically increased in the Western world in recent years. In contrast, CDI is rarely reported in China, possibly due to under-diagnosis. This article briefly summarizes CDI incidence, management and preventive strategies. The authors intend to raise awareness of this disease among Chinese physicians and health workers, in order to minimize the medical and economic burden of a potential epidemic in the future.

Advances in inflammatory bowel disease pathogenesis: linking host genetics and the microbiome

Studies of the genetics underlying inflammatory bowel diseases have increased our understanding of the pathways involved in both ulcerative colitis and Crohn's disease and focused attention on the role of the microbiome in these diseases. Full understanding of pathogenesis will require a comprehensive grasp of the delicate homeostasis between gut bacteria and the human host. In this review, we present current evidence of microbiome-gene interactions in the context of other known risk factors and mechanisms, and describe the next steps necessary to pair genetic variant and microbiome sequencing data from patient cohorts. We discuss the concept of dysbiosis, proposing that the functional composition of the gut microbiome may provide a more consistent definition of dysbiosis and may more readily provide evidence of genome-microbiome interactions in future exploratory studies.

The antimicrobial peptide cathelicidin modulates Clostridium difficile-associated colitis and toxin A-mediated enteritis in mice

BACKGROUND

Clostridium difficile mediates intestinal inflammation by releasing toxin A (TxA), a potent enterotoxin. Cathelicidins (Camp as gene name, LL-37 peptide in humans and mCRAMP peptide in mice) are antibacterial peptides that also posses anti-inflammatory properties.

OBJECTIVES

To determine the role of cathelicidins in models of Clostridium difficile infection and TxA-mediated ileal inflammation and cultured human primary monocytes.

DESIGN

Wild-type (WT) and mCRAMP-deficient (Camp(-/-)) mice were treated with an antibiotic mixture and infected orally with C difficile. Some mice were intracolonically given mCRAMP daily for 3 days. Ileal loops were also prepared in WT mice and treated with either saline or TxA and incubated for 4 h, while some TxA-treated loops were injected with mCRAMP.

RESULTS

Intracolonic mCRAMP administration to C difficile-infected WT mice showed significantly reduced colonic histology damage, apoptosis, tissue myeloperoxidase (MPO) and tumour necrosis factor (TNF)α levels. Ileal mCRAMP treatment also significantly reduced histology damage, tissue apoptosis, MPO and TNFα levels in TxA-exposed ileal loops. WT and Camp(-/-) mice exhibited similar intestinal responses in both models, implying that C difficile/TxA-induced endogenous cathelicidin may be insufficient to modulate C difficile/TxA-mediated intestinal inflammation. Both LL-37 and mCRAMP also significantly reduced TxA-induced TNFα secretion via inhibition of NF-κB phosphorylation. Endogenous cathelicidin failed to control C difficile and/or toxin A-mediated inflammation and even intestinal cathelicidin expression was increased in humans and mice.

CONCLUSION

Exogenous cathelicidin modulates C difficile colitis by inhibiting TxA-associated intestinal inflammation. Cathelicidin administration may be a new anti-inflammatory treatment for C difficile toxin-associated disease.

Clostridium difficile infection and inflammatory bowel disease

The prevalence of Clostridium difficile infection (CDI) in inflammatory bowel disease (IBD) has become a focus of increased attention, as the C. difficile epidemic continues to grow. Although first documented more than 20 years ago, only in recent years has the relationship between these 2 entities been better clarified, and recent epidemiologic studies have shown that IBD patients are at increased susceptibility for CDI compared with the general population. Despite this increased attention, much still remains unknown, and the overlapping clinical presentations of CDI and IBD pose barriers to diagnosis and standardized treatment. Moreover, given the relationship between mortality and severity of CDI in IBD patients, early recognition of those who are at increased risk for infection is of paramount importance to improve patient outcome.

Genetic risk factors for Clostridium difficile infection in ulcerative colitis

BACKGROUND

Patients with inflammatory bowel disease (IBD) are at higher risk for Clostridium difficile infection (CDI). Disruption of gut microbiome and interaction with the intestinal immune system are essential mechanisms for pathogenesis of both CDI and IBD. Whether genetic polymorphisms associated with susceptibility to IBD are also associated with risk of CDI is unknown.

AIMS

To use a well-characterised and genotyped cohort of patients with UC to (i) identify clinical risk factors for CDI; (ii) examine if any of the IBD genetic risk loci were associated with CDI; and (iii) to compare the performance of predictive models using clinical and genetic risk factors in determining risk of CDI.

METHODS

We used a prospective registry of patients from a tertiary referral hospital. Medical record review was performed to identify all ulcerative colitis (UC) patients within the registry with a history of CDI. All patients were genotyped on the Immunochip. We examined the association between the 163 risk loci for IBD and risk of CDI using a dominant genetic model. Model performance was examined using receiver operating characteristics curves.

RESULTS

The study included 319 patients of whom 29 developed CDI (9%). Female gender and pancolitis were associated with increased risk, while use of anti-TNF was protective against CDI. Six genetic polymorphisms including those at TNFRSF14 [Odds ratio (OR) 6.0, P-value 0.01] were associated with increased risk while 2 loci were inversely associated. On multivariate analysis, none of the clinical parameters retained significance after adjusting for genetics. Presence of at least one high-risk locus was associated with an increase in risk for CDI (20% vs. 1%) (P = 6 × 10⁻⁹). Compared to 11% for a clinical model, the genetic loci explained 28% of the variance in CDI risk and had a greater AUROC.

CONCLUSION

Host genetics may influence susceptibility to Clostridium difficile infection in patients with ulcerative colitis.

Treatment of an initial infection with clostridium difficile in patients with inflammatory bowel disease

: Although the incidence of Clostridium difficile-associated diarrhea in the general population has increased dramatically over the past decade, an even greater rate of infection exists in patients with inflammatory bowel disease. Susceptibility in this population is likely inherent to the pathophysiology and treatment of these diseases. C. difficile infection can cause serious complications and death. Consequently, early diagnosis and initiation of effective antibacterial therapy is imperative. This article evaluates treatment recommendations for an initial episode of C. difficile infection in patients with inflammatory bowel disease based on the current guidelines and a Cochrane systematic review.

Clostridium difficile infection in patients with inflammatory bowel disease: An update

Inflammatory bowel disease (IBD) has many etiological factors, among which microbial factors have attracted more and more attention recently. Studies have demonstrated that the incidence of Clostridium difficile infection (CDI) in both adult and children IBD patients has been rising in recent years. Many drugs such as antibiotics, immunosuppressive agents, and acid-suppressing agents may increase the incidence of CDI. Identifying CDI and selecting effective antibiotics are keys to successful treatment, and immunological and ecological treatments are also useful choices. In this article, we will review the progress in research of CDI in IBD patients.