Clostridium difficile and inflammatory bowel disease

Gut Microbiota and Metabolic Specificity in Ulcerative Colitis and Crohn's Disease

Background: Inflammatory bowel disease (IBD) represents multifactorial chronic inflammatory conditions in the gastrointestinal tract and includes Crohn's disease (CD) and ulcerative colitis (UC). Despite similarities in pathobiology and disease symptoms, UC and CD represent distinct diseases and exhibit diverse therapeutic responses. While studies have now confirmed that IBD is associated with dramatic changes in the gut microbiota, specific changes in the gut microbiome and associated metabolic effects on the host due to CD and UC are less well-understood. Methods: To address this knowledge gap, we performed an extensive unbiased meta-analysis of the gut microbiome data from five different IBD patient cohorts from five different countries using QIIME2, DIAMOND, and STAMP bioinformatics platforms. In-silico profiling of the metabolic pathways and community metabolic modeling were carried out to identify disease-specific association of the metabolic fluxes and signaling pathways. Results: Our results demonstrated a highly conserved gut microbiota community between healthy individuals and IBD patients at higher phylogenetic levels. However, at or below the order level in the taxonomic rank, we found significant disease-specific alterations. Similarly, we identified differential enrichment of the metabolic pathways in CD and UC, which included enriched pathways related to amino acid and glycan biosynthesis and metabolism, in addition to other metabolic pathways. Conclusions: In conclusion, this study highlights the prospects of harnessing the gut microbiota to improve understanding of the etiology of CD and UC and to develop novel prognostic, and therapeutic approaches.

Long-Duration Oral Vancomycin to Treat Clostridioides difficile in Patients With Inflammatory Bowel Disease Is Associated With a Low Rate of Recurrence

OBJECTIVES

Patients with inflammatory bowel disease (IBD) are susceptible to Clostridioides difficile infections (CDIs), suffering from greater morbidity and mortality than the general population. Previous studies have proven the efficacy of oral vancomycin therapy in CDI, but there are no definitive guidelines to treat patients with IBD. We assessed the relationship between the length of vancomycin therapy and rates of CDI recurrence and reinfection in patients with IBD.

METHODS

We compared rates of CDI recurrence and reinfection in Crohn's disease and ulcerative colitis (UC) patients receiving long-duration (LD) and short-duration (SD) oral vancomycin therapy, defined as 21-42 days and 10-14 days, respectively. Recurrence and reinfection were defined as positive C. difficile toxin assay by polymerase chain reaction within 8 weeks of the end of antibiotic therapy and after 8 weeks of the end of antibiotic therapy, respectively. The Fisher exact test was used to test for significance, and multivariate logistic regression models were constructed to control for other covariables.

RESULTS

One hundred thirty-four patients with IBD (57 ulcerative colitis and 77 Crohn's disease) met inclusion criteria. LD vancomycin had a 1.8% incidence of CDI recurrence, compared with 11.7% in the SD vancomycin group (odds ratio = 0.13, P = 0.043). CDI reinfection rates and time to reinfection were not significantly different (LD 14.0% vs SD 16.9%, P = NS). Multivariate logistic regression models showed that treatment with LD vancomycin had lower odds for recurrence than SD vancomycin (odds ratio = 0.03, P = 0.021).

DISCUSSION

LD vancomycin is associated with lower rates of CDI recurrence compared with SD vancomycin therapy. These results will help guide clinical decisions and the development of a prospective trial.

Clostridium difficile Infection at Diagnosis and during the Disease Course of Pediatric Inflammatory Bowel Disease

PURPOSE

Clostridium difficile colonization and infection are commonly associated with poor outcomes in patients with pediatric inflammatory bowel disease (PIBD). We aimed to investigate the prevalence of C. difficile colonization and infection at the time of diagnosis and to evaluate risk factors associated with the development of C. difficile infection during the course of PIBD treatment.

METHODS

We retrospectively enrolled a total of 59 children who were newly diagnosed with PIBD at the tertiary medical center. All patients underwent C. difficile toxin assays and cultures initially and at every follow-up during the disease course. Kaplan-Meier survival analysis and Cox regression test were used for statistical analysis.

RESULTS

Initial cultures for C. difficile were positive in 13 (22.0%) of 59 PIBD patients, whereas initial toxin assays were positive in 3 patients (5.1%). During treatment, C. difficile cultures converted to positive in 28 (47.5%) in addition to 13 patients who were initially culture-positive, and C. difficile toxins converted to positive in 13 (22.0%) in addition to 3 originally toxin-positive patients. Antibiotic usage alone was significantly associated with the development of C. difficile colonization (p=0.011), and the length of hospitalization was associated with the development of C. difficile infection (p=0.032).

CONCLUSION

C. difficile colonization and infection occur frequently during the disease course of PIBD. Antibiotic usage and longer hospital stay were significant risks factors for the conversion of C. difficile status in PIBD patients undergoing treatment.

Case-Control Study of Inflammatory Bowel Disease Patients with and without Clostridium difficile Infection and Poor Outcomes in Patients Coinfected with C. difficile and Cytomegalovirus

BACKGROUND AND AIMS

Clostridium difficile infection (CDI) incidence and risk factors in patients with inflammatory bowel disease (IBD) have been extensively studied. However, data describing CDI in Chinese patients with IBD are limited. We investigated the cumulative incidence, risk factors, and outcomes of CDI in Chinese IBD patients.

METHODS

We conducted a retrospective, case-control study of patients hospitalized with IBD and CDI at Peking Union Medical College Hospital from January 2010 to December 2015. CDI was diagnosed based on the presence of active symptoms and positive enzyme immunoassay-based stool test results for C. difficile toxin A or B (CDAB). Controls were selected from CDAB-negative patients with IBD and matched by age, gender, phenotypes of IBD and the same time period of CDAB testing at a 1:2 or 1:3 ratio.

RESULTS

We identified 60 (7.41%) cases of CDI among 810 patients with IBD, and 137 control cases were selected. Univariate analysis revealed that IBD patients with CDI had higher rates of concurrent corticosteroid use, proton pump inhibitor, antibiotic use, recent hospitalization, parenteral nutrition support, and cytomegalovirus (CMV) coinfection (P < 0.05). Multivariate analysis revealed that concurrent corticosteroid use (odds ratio [OR] = 6.803, 95% confidence interval [CI] = 2.901-15.954, P < 0.001) and hospitalization within 1 month (OR = 3.028, 95% CI = 1.225-7.480, P = 0.016) were associated with CDI. CMV and C. difficile coinfection (hazard ratio [HR] = 4.185, 95% CI = 1.492-11.736, P = 0.007) as well as disease severity (HR 2.070, 95% CI = 1.006-4.261, P = 0.048) were independently associated with colectomy following CDI.

CONCLUSIONS

IBD patients with concurrent corticosteroid use and recent hospitalization are at a higher risk of CDI. CMV and C. difficile coinfection is associated with poorer outcomes.

Increased Rate of Venous Thromboembolism in Hospitalized Inflammatory Bowel Disease Patients with Clostridium Difficile Infection

BACKGROUND

Risk of venous thromboembolism (VTE) in patients with inflammatory bowel disease (IBD) is well established; however, there is paucity of data on the potential added risk of VTE in patients with IBD with Clostridium difficile infection (CDI). We sought to study the difference in VTE rates in hospitalized patients with IBD with CDI compared to those without CDI.

METHODS

We queried Nationwide Inpatient Sample from year 2011 to identify patients ≥18 years of age with a discharge diagnosis of IBD (i.e., Crohn's disease and ulcerative colitis) based on ICD-9-CM codes 555.xx and 556.xx, respectively. Patients were further divided into 2 groups: those with and without CDI. To adjust and control for potential baseline differences between groups, 1:1 propensity matching was performed. Multivariate regression analysis was used to evaluate the difference in VTE rates in 2 groups.

RESULTS

Of 312,147 patients with the discharge diagnosis of IBD, 12,560 (4%) had CDI. VTE was present 6% in group with CDI versus 3% in group without CDI (P < 0.001). On performing multivariate analysis after propensity-score matching, CDI was significantly associated with VTE (adjusted odds ratio 1.7, 95% confidence interval 1.4-2.2, P < 0.001). On subgroup analysis, Crohn's disease with CDI had a higher association with VTE compared with Crohn's disease only. Similarly, ulcerative colitis with CDI had a higher association with VTE compared with ulcerative colitis only.

CONCLUSIONS

Rate of VTE was higher in hospitalized patients with IBD with CDI compared with those without CDI, necessitating extra vigilance in this patient population.

A comprehensive review and update on Crohn's disease

The term inflammatory bowel disease (IBD) refers principally to two major categories of chronic relapsing inflammatory intestinal disorders: Crohn's disease (CD) and ulcerative colitis (UC). In the United States, it is currently estimated that about 1.5 million people suffer from IBD, causing considerable suffering, mortality and economic loss every year. Yet the cause of IBD is unknown, and until we understand more, prevention or cure will not be possible. There is a lot of variation in the incidence and prevalence of CD based on geographic region, environment, immigrant population, and ethnic groups. The annual incidence of CD in North America is reported to be 3.1-20.2 per 100,000 with a prevalence of 201 per 100,000 population. Based on the epidemiological, genetic and immunological data, CD is considered to be a heterogeneous disorder with multifactorial etiology in which genetics and environment interact to manifest the disease. Several genes have been studied so for with respect to CD, but thus far the strong and replicated associations have been identified with NOD2, IL23R and ATG16L1 genes. The risk factors implicated with CD include smoking, low fiber- high carbohydrate diet, altered microbiome and medications such as non-steroidal anti-inflammatory drugs. CD is typically characterized by transmural inflammation of the intestine and could affect any part of the gastrointestinal tract from mouth to perianal area. In terms of distribution of the disease 25% of the patients have colitis only, 25% is ileitis only and 50% have ileocolitis. The Montreal classification is based on the age at diagnosis (<16, 17-40, > 40), disease location (Ileal, colonic, Ileocolonic) and the disease behavior (nonstricturing/nonpenetrating, stricturing, penetrating). The key features for diagnosing CD comprises a combination of radiographic, endoscopic and pathological findings demonstrating focal, asymmetric, transmural or granulomatous features. Abdominal Computed tomography (CT) enterography is the most preferred first-line radiologic study used in the assessment of small bowel CD. The diagnostic accuracy of magnetic resonance enterography/enteroclysis is similar to that of CT scans and also prevents exposure to ionizing radiation. Endoscopic scores are considered to be the gold standard tool to measure the activity of CD and they are used more commonly in the clinical trials to measure the efficacy of various drugs on inducing and maintaining mucosal healing. The most common scoring systems used to measure clinical disease activity include Crohn's Disease Activity Index (CDAI), HBI- Harvey-Bradshaw index (HBI), short inflammatory bowel disease questionnaire (SIBDQ) and Lehmann score. Management of Crohn's disease has been seen as an evolving challenge owing to its widely heterogeneous manifestations, overlapping characteristics with other inflammatory disorders, often elusive extraintestinal manifestations and uncertain etiology. Therapeutic interventions are tailored to address symptomatic response and subsequent tolerance of the intervention. Chronology of treatment should favor treatment dose acute disease or "induction therapy", followed by maintenance of adequate response or remission, i.e. "maintenance therapy". The medications which are highly effective in inducing remission include steroids and Tumor Necrosis Factor (TNF) inhibitors. Medications used to maintain remission include 5-aminosalicyclic acid products, immunomodulators (Azathioprine, 6-mercaptopurine, methotrexate) and TNF inhibitors (infliximab, adalimumab, certolizumab and golimumab). Surgical interventions like bowel resection, stricturoplasty or drainage of abscess is required in up to two thirds of CD patients during their lifetime. The most common indications for surgical resection are medically refractory disease, perforation, persisting or recurrent obstruction, abscess not amenable to percutaneous drainage, intractable hemorrhage, dysplasia or cancer. Endoscopic recurrence in postoperative CD patients, as defined by Rutgeers score i2-i4 occur in 30-90% of the patients at the neoterminal ileum within 12 months of surgery and almost universally by 5 years. Treating CD requires a comprehensive care team including the patient, primary care provider, and gastroenterologist. In summary CD is a chronic inflammatory condition with a remitting and relapsing course primarily affecting relatively younger population with significant socioeconomic effects.

Clostridium difficile Enterocolitis and Reactive Arthritis: A Case Report and Review of the Literature

Reactive arthritis is a rare complication of Clostridium difficile enterocolitis, especially in children. We review the 6 pediatric cases published in the English and non-English literature and discuss their clinical presentation, outcome, treatment, and pathophysiology. We also report the seventh case of Clostridium difficile reactive arthritis in a 6-year-old boy who was treated with amoxicillin-clavulanate for 10 days because of an upper respiratory infection. After the antibiotic course, the child developed at the same time diarrhea with positive stool culture for Clostridium difficile and an asymmetric polyarthritis. Nonsteroidal anti-inflammatory drugs and metronidazole completely resolved the pain, joint swelling, and diarrhea. After twelve months of follow-up there has been no recurrence. This report confirms the self-limiting course of Clostridium difficile reactive arthritis. Clostridium difficile testing in children with gastrointestinal symptoms and acute onset of joint pain should be always considered.

Inflammatory Bowel Disease: Historical Perspective, Epidemiology, and Risk Factors

Inflammatory bowel disease (IBD) describes a group of closely related yet heterogeneous predominantly intestinal disease processes that are a result of an uncontrolled immune mediated inflammatory response. It is estimated that approximately one and a half million persons in North America have IBD. Pathogenesis of IBD involves an uncontrolled immune mediated inflammatory response in genetically predisposed individuals to a still unknown environmental trigger that interacts with the intestinal flora. There continues to be an enormous amount of information emanating from epidemiological studies providing expanded insight into the occurrence, distribution, determinants, and mechanisms of inflammatory bowel disease.

The impact of Clostridum difficile on surgical rate among ulcerative colitis patients: A systemic review and meta-analysis

There is growing recognition of the impact of Clostridum difficile infection (CDI) on patients with inflammatory bowel disease. Clostridium difficile infection causes greater morbidity and mortality. This study aimed to evaluate the impact of C. difficile on surgical risk among ulcerative colitis (UC) patients. We searched the following databases: MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, ACP Journal Club, DARE, CMR, and HTA. Studies were included if fulfilled the following criteria: (1) Cohort or case-control studies, which involved a comparison group that lacked CDI, (2) Patients were given a primary diagnosis of UC, (3) Comorbidity of CDI was evaluated by enzyme immunoassay of stool for C. difficile toxin A and B or C. difficile stool culture, (4) Studies evaluated surgical rate, and (5) Studies reported an estimate of odds ratio, accompanied by a corresponding measure of uncertainty. Five studies with 2380 patients fulfilled the inclusion criteria. Overall, meta-analysis showed that UC with CDI patients had a significant higher surgical rate than patients with UC alone. (OR=1.76, 95% CI=1.36-2.28). C. difficile infection increased the surgical rate in UC patients. However, results should be interpreted with caution, given the limitations of this stud.

Epidemiology and risk factors for IBD

IBD, comprising Crohn's disease and ulcerative colitis, is a chronic immunologically mediated disease at the intersection of complex interactions between genetics, environment and gut microbiota. Established high-prevalence populations of IBD in North America and Europe experienced the steepest increase in incidence towards the second half of the twentieth century. Furthermore, populations previously considered 'low risk' (such as in Japan and India) are witnessing an increase in incidence. Potentially relevant environmental influences span the spectrum of life from mode of childbirth and early-life exposures (including breastfeeding and antibiotic exposure in infancy) to exposures later on in adulthood (including smoking, major life stressors, diet and lifestyle). Data support an association between smoking and Crohn's disease whereas smoking cessation, but not current smoking, is associated with an increased risk of ulcerative colitis. Dietary fibre (particularly fruits and vegetables), saturated fats, depression and impaired sleep, and low vitamin D levels have all been associated with incident IBD. Interventional studies assessing the effects of modifying these risk factors on natural history and patient outcomes are an important unmet need. In this Review, the changing epidemiology of IBD, mechanisms behind various environmental associations and interventional studies to modify risk factors and disease course are discussed.

Environmental risk factors for inflammatory bowel diseases: a review

Inflammatory bowel diseases comprising Crohn's disease (CD) and ulcerative colitis (UC) are chronic immunologically mediated diseases. The key mechanism underlying the pathogenesis of these diseases is a dysregulated immune response to commensal flora in a genetically susceptible host. Thus intestinal microbial dysbiosis, host genetics, and the external environment all play an important role in the development of incident disease and in determining subsequent disease behavior and outcomes. There are several well-defined or putative environmental risk factors including cigarette smoking, appendectomy, diet, stress and depression, vitamin D as well as hormonal influence. The effect of some of the risk factors appears to differ between CD and UC suggesting that despite shared genetic and immunologic mechanisms, distinct pathways of pathogenesis exist. There is a growing body of literature identifying risk factors for incident disease. There is less rigorous literature defining triggers of relapse, and few controlled clinical trials examining if modification of such risk factors results in an improvement in patient outcomes. This is an area of considerable patient, physician, and scientific interest, and there is an important unmet need for rigorous studies of the external environment in disease pathogenesis and subsequent course.

Vitamin D deficiency is associated with community-acquired clostridium difficile infection: a case-control study

Background

Clostridium difficile infection (CDI) is increasingly recognized as an important community acquired pathogen causing disease (CA-CDI). Vitamin D [25(OH)D] has immune modulatory effects and plays an important role in intestinal immunity. The role of vitamin D in CA-CDI has not been examined previously.

Methods

This was a single referral center case–control study. Cases comprised of all patients with CA-CDI who had a serum 25(OH)D measured within 12 months prior to infection. Controls were drawn from patients who had 25(OH)D checked and matched based on age, gender, race and health status. Serum 25(OH)D was stratified as < 15 ng/mL, 15-30 ng/mL or > 30 ng/mL. Regression models adjusting for potential confounders were used to define independent association between vitamin D and CA-CDI.

Results

We identified 58 matched case–control pairs (66% women; 85% Caucasian). The mean age was 62 years. The mean serum 25(OH)D level was significantly lower in CA-CDI cases compared to controls (28.5 ng/mL vs. 33.8 ng/mL, p = 0.046). Cases had higher rate of antibiotic exposure and more comorbidity. Serum 25(OH)D < 15 ng/mL was associated with an increased risk of CA-CDI on univariate (Odds ratio (OR) 5.10, 95% confidence interval (CI) 1.51 – 17.24) and multivariate analysis (OR 3.84, 95% CI 1.10 – 13.42). Vitamin D levels between 15-30 ng/mL did not modify disease risk.

Conclusions

Low serum 25(OH)D < 15 ng/mL was associated with increased risk of CA-CDI. This suggests vitamin D may have a role in determining susceptibility to CA-CDI.

Clostridium difficile infection in the postcolectomy patient

Clostridium difficile infection (CDI) after total colectomy has been increasingly recognized over the past decade. C. difficile enteritis (CDE) is a rare occurrence, whereas C. difficile pouchitis (CDP) has been reported in approximately 10% of symptomatic patients seen at a referral center for pouch dysfunction. Similar to colonic CDI in the general population, antibiotic use and comorbid diseases may be risk factors for CDE. In contrast, the postoperative use of antibiotics does not seem to be associated with CDP, whereas male gender, recent hospitalization, and presurgery antibiotic use were shown to be risk factors for CDP. C. difficile is capable of colonizing all intestinal sites, including the ileal pouch. Similarities with the colon at physiological and cellular levels may contribute to the susceptibility of the ileal pouch to CDI. Postcolectomy CDI likely represents a disease spectrum from asymptomatic colonization to severe symptomatic infection. CDI should be considered in ostomy patients with fever and increased ileostomy output and in ileal pouch patients with a change in "normal" symptom pattern or chronic antibiotic-refractory pouchitis. Sensitive and specific methods for detection of CDI are available, and endoscopy is useful in evaluating the patient with suspected CDE or CDP, although pseudomembranes are typically absent. Vancomycin is used as the first-line therapy for CDP and may be warranted for patients with inflammatory bowel disease with CDE. Fecal microbiota transplantation has found its use in the management of severe or antibiotic refractory CDP, but this approach requires evaluation for the management of refractory CDE.

Risk factors for the development of Clostridium difficile infection in hospitalized children

PURPOSE OF REVIEW

This article defines the risk factors for Clostridium difficile infection (CDI) in hospitalized children in light of recent studies demonstrating a change in the epidemiology of these infections in both adults and children.

RECENT FINDINGS

Antibiotic exposure within the past 4-12 weeks was noted in a majority of published cases of pediatric CDI, and that remains a key risk factor for infection. Past and/or prolonged hospitalization increase a child's risk for CDI as they increase potential contact with C. difficile spores. Of all CDI, hospital-acquired infection remains more common. Many comorbid conditions have been linked with CDI, with the strongest association existing in children with cancer and inflammatory bowel disease. Severe infections occur infrequently in pediatric patients. Markers established in adults for severe CDI resulting in colectomy or transfer to ICU have not been shown to correlate in pediatric patients.

SUMMARY

Recent antibiotic exposure and hospitalization remain key risk factors for CDI in the hospitalized pediatric patient. Patients with comorbid conditions such as malignancy and inflammatory bowel disease are at higher risk for CDI. Resistant infections and severe outcomes are not common in the pediatric population.

Case Records of the Massachusetts General Hospital. Case 25-2014. A 37-year-old man with ulcerative colitis and bloody diarrhea

A 37-year-old man with ulcerative colitis was admitted to the hospital because of abdominal cramping, diarrhea, hematochezia, fever to a peak temperature of 38.8 °C, and drenching night sweats. Several weeks earlier, he had performed home fecal transplantation.

Emergence of fecal microbiota transplantation as an approach to repair disrupted microbial gut ecology

In the recent years fecal microbiota transplantation (FMT) has emerged as an effective therapeutic option for patients with refractory Clostridium difficile infection that is not responding to antibiotic therapy. It results in implantation of donor microbiota into recipients and restoration of normal distal gut microbial community structure. We anticipate that this form of therapy represents merely the first entry into a new class of therapeutics. There is great interest in application of FMT or defined microbial consortia to treatment of many diseases associated with dysbiosis. However, many challenges remain in development as our understanding of microbial ecology within the human body and microbiota-host interactions remain limited. Future advances in this field will be critically depending on detailed mechanistic understanding.

First case report of de novo ulcerative colitis developing after orthotopic liver transplantation successfully treated by granulocyte and monocyte apheresis

BACKGROUND

Immunosuppressants such as tacrolimus and cyclosporine are prescribed long-term after orthotopic liver transplantation (OLT) to prevent allograft rejection. Although these immunosuppressants are known to effectively control ulcerative colitis (UC), some post-OLT patients develop exacerbation of preexisting UC or de novo UC. Although aminosalicylates and corticosteroid courses are usually effective to treat such UC, several patients have developed uncontrollable disease and required colectomies.

CASE REPORT

We have reported a patient who developed de novo UC after OLT to treat liver cirrhosis and hepatocellular carcinoma associated with hepatitis B virus (HBV) infection. Existence of the HBV infection made us avoid to increase the corticosteroid dose or to use other immunosuppressants such as azathioprine or infliximab.

CONCLUSIONS

In this patient, granulocyte and monocyte apheresis was highly effective in terms of inducing remission of de novo UC. No adverse event was noted.

Clostridium difficile infection in patients with ileal pouches

Clostridium difficile (C. difficile) infection (CDI) following total proctocolectomy and ileal pouch-anal anastomosis has been increasingly recognized over the past 5 years. CDI of the ileal pouch has been recognized in ∼10% of symptomatic patients seen at a tertiary referral center for pouch dysfunction. In contrast to colonic CDI in the general population or in patients with inflammatory bowel disease, postoperative antibiotic exposure and the use of immunosuppressive agents or proton pump inhibitors do not appear to be associated with CDI of the pouch. Male gender, recent hospitalization, and presurgery antibiotic use were shown to be risk factors for ileal pouch CDI. The ileal pouch may be susceptible to CDI owing to similarities with the colon at physiological and structural levels. Postcolectomy CDI likely represents a spectrum of disease processes, varying from asymptomatic colonization to severe symptomatic infection. CDI should be considered in any patient with an ileal pouch presenting with a change in "normal" symptom pattern or treatment-refractory disease. Sensitive and specific methods for the detection of CDI are available, and pouchoscopy is a valuable tool in the evaluation of the patient with symptomatic CDI of the pouch. At a referral center for pouch dysfunction, vancomycin is used as the first-line therapy for ileal pouch CDI. Fecal microbiota transplantation may find use in the management of severe or antibiotic refractory CDI-related pouchitis.

Higher plasma vitamin D is associated with reduced risk of Clostridium difficile infection in patients with inflammatory bowel diseases

BACKGROUND

Patients with inflammatory bowel diseases (IBD) have an increased risk of clostridium difficile infection (CDI). Cathelicidins are anti-microbial peptides that attenuate colitis and inhibit the effect of clostridial toxins. Plasma calcifediol [25(OH)D] stimulates production of cathelicidins.

AIM

To examine the association between plasma 25(OH)D and CDI in patients with IBD.

METHODS

From a multi-institutional IBD cohort, we identified patients with at least one measured plasma 25(OH)D. Our primary outcome was development of CDI. Multivariate logistic regression models adjusting for potential confounders were used to identify independent effect of plasma 25(OH)D on risk of CDI.

RESULTS

We studied 3188 IBD patients of whom 35 patients developed CDI. Patients with CDI-IBD were older and had greater co-morbidity. The mean plasma 25(OH)D level was significantly lower in patients who developed CDI (20.4 ng/mL) compared to non-CDI-IBD patients (27.1 ng/mL) (P = 0.002). On multivariate analysis, each 1 ng/mL increase in plasma 25(OH)D was associated with a 4% reduction in risk of CDI (OR 0.96, 95% CI 0.93-0.99, P = 0.046). Compared to individuals with vitamin D >20 ng/mL, patients with levels <20 ng/mL were more likely to develop CDI (OR 2.27, 95% CI 1.16-4.44). The mean plasma 25(OH)D in patients with CDI who subsequently died was significantly lower (12.8 ± 8.1 ng/mL) compared to those who were alive at the end of follow-up (24.3 ± 13.2 ng/mL) (P = 0.01).

CONCLUSIONS

Higher plasma calcifediol [25(OH)D] is associated with reduced risk of C. difficile infection in patients with IBD. Further studies of therapeutic supplementation of vitamin D in patients with inflammatory bowel disease and C. difficile infection may be warranted.

Reset of a critically disturbed microbial ecosystem: faecal transplant in recurrent Clostridium difficile infection

Recurrent Clostridium difficile infection (CDI) can be effectively treated by infusion of a healthy donor faeces suspension. However, it is unclear what factors determine treatment efficacy. By using a phylogenetic microarray platform, we assessed composition, diversity and dynamics of faecal microbiota before, after and during follow-up of the transplantation from a healthy donor to different patients, to elucidate the mechanism of action of faecal infusion. Global composition and network analysis of the microbiota was performed in faecal samples from nine patients with recurrent CDI. Analyses were performed before and after duodenal donor faeces infusion, and during a follow-up of 10 weeks. The microbiota data were compared with that of the healthy donors. All patients successfully recovered. Their intestinal microbiota changed from a low-diversity diseased state, dominated by Proteobacteria and Bacilli, to a more diverse ecosystem resembling that of healthy donors, dominated by Bacteroidetes and Clostridium groups, including butyrate-producing bacteria. We identified specific multi-species networks and signature microbial groups that were either depleted or restored as a result of the treatment. The changes persisted over time. Comprehensive and deep analyses of the microbiota of patients before and after treatment exposed a therapeutic reset from a diseased state towards a healthy profile. The identification of microbial groups that constitute a niche for C. difficile overgrowth, as well as those driving the reinstallation of a healthy intestinal microbiota, could contribute to the development of biomarkers predicting recurrence and treatment outcome, identifying an optimal microbiota composition that could lead to targeted treatment strategies.

Treatment of relapsing Clostridium difficile infection using fecal microbiota transplantation

BACKGROUND

Clostridium difficile infection (CDI) has become a global concern over the last decade. In the United States, CDI escalated in incidence from 1996 to 2005 from 31 to 64/100,000. In 2010, there were 500,000 cases of CDI with an estimated mortality up to 20,000 cases a year. The significance of this problem is evident from the hospital costs of over 3 billion dollars annually. Fecal microbiota transplant (FMT) was first described in 1958 and since then about 500 cases have been published in literature in various small series and case reports. This procedure has been reported mainly from centers outside of the United States and acceptance of the practice has been difficult. Recently the US Food and Drug Administration (FDA) labeled FMT as a biological drug; as a result, guidelines will soon be required to help establish it as a mainstream treatment. More US experience needs to be reported to popularize this procedure here and form guidelines.

METHOD

We did a retrospective review of our series of patients with relapsing CDI who were treated with FMT over a 3-year period. We present our experience with FMT at a community hospital as a retrospective review and describe our procedure.

RESULTS

There were a total of 12 patients who underwent FMT for relapsing C. difficile. Only one patient failed to respond and required a second FMT. There were no complications associated with the transplant and all patients had resolution of symptoms within 48 hours of FMT.

CONCLUSION

FMT is a cheap, easily available, effective therapy for recurrent CDI; it can be safely performed in a community hospital setting with similar results.

Surgical Management of Clostridium difficile Colitis

Clostridium difficile infection (CDI) will progress to fulminant disease in 3 to 5% of cases. With the emergence of hypervirulent, multidrug-resistant strains, the incidence and severity of disease are continuing to rise. Prompt identification, early resuscitation, and treatment are critical in preventing morbidity and mortality in this increasingly common condition. Discontinuation of antibiotics and treatment with oral vancomycin and intravenous or oral metronidazole are first-line treatments, but complicated cases may require surgery. Subtotal colectomy with ileostomy remains the standard of care when toxic megacolon, perforation, or an acute surgical abdomen is present, but mortality rates are high. Recognition of risk factors for fulminant CDI and earlier surgical intervention may decrease mortality from this highly lethal disease.

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.

Moving fecal microbiota transplantation into the mainstream

In recent years, fecal microbiota transplantation (aka fecal transplantation, fecal bacteriotherapy, FMT) has become increasing utilized to treat recurrent and refractory Clostridium difficile infection (CDI). Almost 600,000 cases of CDI occur each year in the United States. Of these, an estimated 15,000 patients have a recurrence. The management of recurrent disease has been challenging for patients and clinicians. Increasingly, FMT has been recognized as an effective option for these patients. This article explores why FMT has reemerged as a practical therapeutic modality. In the process, the logistics by which the procedure is performed and the factors that may affect quality, safety, and patient outcomes will be described.

Health care burden of Clostridium difficile infection in hospitalized children with inflammatory bowel disease

BACKGROUND

Children with inflammatory bowel disease (IBD), similar to adults, are at increased risk of acquiring a Clostridium difficile infection (CDI). Our objective was to characterize the health care burden associated with CDI in hospitalized pediatric patients with IBD.

METHODS

We extracted and analyzed cases with a discharge diagnosis of IBD or CDI from the U.S. Healthcare Cost and Utilization Project Kids' Inpatient Database.

RESULTS

In our primary analysis, we evaluated pediatric cases with a principal diagnosis of IBD or CDI. For the year 2009, we identified 12,610 weighted cases with IBD of which 3.5% had CDI. In children with IBD, CDI was independently associated with lengthier hospital stays (8.0 versus 6.0 days; adjusted regression coefficient, 2.1 days; 95% confidence interval [CI], 1.4-2.8), higher charges ($45,126 versus $34,703; adjusted regression coefficient, $11,506; 95% CI, 6192-16,820), and greater need for parenteral nutrition (15.9% versus 12.1%; adjusted odds ratio, 1.5; 95% CI, 1.1-2.0) and blood transfusion (17.7% versus 9.8%; adjusted odds ratio, 1.8; 95% CI, 1.4-2.4). There were no deaths. We made similar observations in a subanalysis of cases with principal or secondary diagnoses of IBD or CDI. The incidence of CDI in patients with IBD increased between 2000 and 2009 from 21.7 to 28.0 cases per 1000 IBD cases per year (P < 0.001). There was a significant increase in CDI complicating ulcerative colitis (28.1 versus 42.2, P < 0.001) but not for Crohn's disease (18.3 versus 20.3).

CONCLUSIONS

CDI represents a significant health care burden in hospitalized children with IBD.

Guidelines for diagnosis, treatment, and prevention of Clostridium difficile infections

Clostridium difficile infection (CDI) is a leading cause of hospital-associated gastrointestinal illness and places a high burden on our health-care system. Patients with CDI typically have extended lengths-of-stay in hospitals, and CDI is a frequent cause of large hospital outbreaks of disease. This guideline provides recommendations for the diagnosis and management of patients with CDI as well as for the prevention and control of outbreaks while supplementing previously published guidelines. New molecular diagnostic stool tests will likely replace current enzyme immunoassay tests. We suggest treatment of patients be stratified depending on whether they have mild-to-moderate, severe, or complicated disease. Therapy with metronidazole remains the choice for mild-to-moderate disease but may not be adequate for patients with severe or complicated disease. We propose a classification of disease severity to guide therapy that is useful for clinicians. We review current treatment options for patients with recurrent CDI and recommendations for the control and prevention of outbreaks of CDI.

Risk factors and outcome of PCR-detected Clostridium difficile infection in ileal pouch patients

BACKGROUND

The clinical implication of Clostridium difficile infection (CDI) in patients with ileal pouch-anal anastomosis (IPAA) for underlying inflammatory bowel disease (IBD) has not been well studied. This study was designed to investigate the cumulative incidence, risk factors, and outcome of CDI in patients with ileal pouches.

METHODS

Consecutive IPAA patients (n = 196) from the subspecialty Pouchitis Clinic with an increase of at least three stools per day more from the postoperative baseline for more than 4 weeks were enrolled from October 2010 to December 2011. CDI was diagnosed based on the presence of symptoms and positive polymerase chain reaction (PCR)-based stool test for C. difficile toxin B. Risk factors for CDI were assessed with univariate and multivariate analyses. All patients with CDI (n = 21) were treated with oral vancomycin (500 - 1000 mg/day) for 2-4 weeks. The treatment outcome of these patients was documented.

RESULTS

Twenty-one patients (10.7%) were diagnosed with CDI. On univariate analysis, patients with CDI had more stool frequency (P = 0.014) and significant current weight loss (P = 0.003) than patients with no CDI. In logistic regression analysis, there was a trend that recent hospitalization (odds ratio [OR] = 4.00, 95% confidence interval [CI], 0.95-16.84) might be associated with CDI. Of the 14 CDI patients with follow-up data, eight (57.1%) had either recurrent (n = 5) or refractory (n = 3) CDI after oral vancomycin therapy.

CONCLUSIONS

A high index of suspicion for CDI in pouch patients should be given to those with recent hospitalization or constitutional symptoms, such as weight loss. Recurrent or refractory CDI is common, even with standard oral vancomycin therapy.

Fecal microbiota transplantation in relapsing Clostridium difficile infection

Clostridium difficile infection rates are Climbing in frequency and severity, and the spectrum of susceptible patients is expanding beyond the traditional scope of hospitalized patients receiving antibiotics. Fecal microbiota transplantation is becoming increasingly accepted as an effective and safe intervention in patients with recurrent disease, likely due to the restoration of a disrupted microbiome. Cure rates of > 90% are being consistently reported from multiple centers. Transplantation can be provided through a variety of methodologies, either to the lower proximal, lower distal, or upper gastrointestinal tract. This review summarizes reported results, factors in donor selection, appropriate patient criteria, and the various preparations and mechanisms of fecal microbiota transplant delivery available to clinicians and patients.

Detecting and treating Clostridium difficile infections in patients with inflammatory bowel disease

The prevalence of CDI in patients with IBD has increased over the last decade. The excess morbidity and mortality associated with CDI appears to be greater in patients with IBD than in those without preexisting bowel disease. The risk factors for CDI in IBD and non-IBD populations appear similar; unique IBD-related risk factors are use of maintenance immunosuppression and extent and severity of prior colitis. Nevertheless, a significant proportion of CDI-IBD patients may have the disease without traditional risk factors (ie, antibiotic use, recent hospitalization). The absence of such risk factors must not preclude considering CDI in the differential diagnosis of IBD patients presenting with a disease flare. Vancomycin and metronidazole appear to have similar efficacy with vancomycin being the preferred agent for severe disease. Early surgical consultation is key for improving outcomes of patients with severe disease. Several gaps in research exist; prospective multicenter cohorts of CDI-IBD are essential to improve our understanding of the impact of CDI on IBD patients and define appropriate therapeutic regimens to improve patient outcomes.

Prospective observational study on antibiotic-associated bloody diarrhea: report of 21 cases with a long-term follow-up from Turkey

OBJECTIVE

Antibiotic-associated hemorrhagic colitis is a distinct form of antibiotic-associated bloody diarrhea (AABD) in which Clostridium difficile is absent. Although the cause is not exactly known, reports have suggested the role of Klebsiella oxytoca and/or C. difficile.

MATERIALS AND METHODS

Between 2001 and 2006, stool samples of 21 consecutive patients with AABD were cultured for common enteric pathogens and K. oxytoca, and were tested for the presence of parasites and C. difficile toxin A+B within the first 24 h of their initial admission and a colonoscopy was performed when available. The patients were followed up prospectively by telephone interviews.

RESULTS

The occurrence of symptoms ranged between 6 h and 14 days following the first dose of the antibiotic responsible and the duration of the AABD ranged between 6 h and 21 days. The antibiotic responsible was oral ampicillin/sulbactam in 18 (85%) cases. C. difficile toxin A+B production by enzyme-linked immunosorbent assay and K. oxytoca growth in stool cultures were detected in six (29%) and 11 (51%) of 21 patients, respectively. Endoscopic morphology and histology in a limited number of patients revealed no more than a nonspecific inflammation and acute colitis, respectively.

CONCLUSION

This study confirms that antibiotic-associated hemorrhagic colitis, as a distinct entity in relation to K. oxytoca, is seen in half of the patients with AABD. Most of the cases are seen within a week following the antibiotic use. Almost all of the patients did not develop any flares during the long-term antibiotic-free follow-up. In some of the patients with AABD, there was coexistence of K. oxytoca with C. difficile toxin A+B.

Clostridium difficile infection in newly diagnosed pediatric patients with inflammatory bowel disease: prevalence and risk factors

BACKGROUND

Epidemiological and microbiological data suggest that Clostridium difficile infection (CDI) plays a substantial role in the clinical initiation of inflammatory bowel disease (IBD). The aim of the present study was to investigate the prevalence and risk factors of CDI in newly diagnosed pediatric patients with IBD.

METHODS

The current investigation was a retrospective study. All patients newly diagnosed with IBD in the pediatric gastroenterology clinic in Warsaw between 2007 and 2010 were included in the present study. The patients were diagnosed according to Porto criteria and microbiology evaluation screening tests for CDI were conducted. Risk factors including prior hospitalization, use of antibiotics within 2 months of CDI detection, colonic involvement, and the duration of symptoms were evaluated. CDI diagnosis was based on a positive stool enzyme immunoassay.

RESULTS

In the present study, 134 patients were evaluated (54 patients with Crohn's disease, and 80 with ulcerative colitis; 87% of the patients had colonic disease). The average age of the patients was 12.3 years, and the prevalence of CDI was 47% (95% confidence interval [CI], 38%-56%). Significant differences in the prevalence of CDI between patients with Crohn's disease and ulcerative colitis (P = 0.72; odds ratio [OR] = 1.187, 95% CI, 0.56-2.52) were not observed. The risk of CDI was associated with an increase in the age of the patient and the severity of the disease.

CONCLUSIONS

The prevalence of CDI in newly diagnosed IBD patients was high and was independent of the type of disease.

Predictors of severe outcomes associated with Clostridium difficile infection in patients with inflammatory bowel disease

BACKGROUND

The increasing incidence of Clostridium difficile (C. difficile) infection (CDI) among patients with inflammatory bowel disease is well recognised. However, most studies have focused on demonstrating that CDI is associated with adverse outcomes in IBD patients. Few have attempted to identify predictors of severe outcomes associated with CDI among IBD patients.

AIM

To identify clinical and laboratory factors that predict severe outcomes associated with CDI in IBD patients.

METHODS

From a multi-institution EMR database, we identified all hospitalised patients with at least one diagnosis code for C. difficile from among those with a diagnosis of Crohn's disease or ulcerative colitis. Our primary outcome was time to total colectomy or death with follow-up censored at 180 days after CDI. Cox proportional hazards models were used to identify predictors of the primary outcome from among demographic, disease-related, laboratory and medication variables.

RESULTS

A total of 294 patients with CDI-IBD were included in our study. Of these, 58 patients (20%) met our primary outcome (45 deaths, 13 colectomy) at a median of 31 days. On multivariate analysis, serum albumin <3 g/dL (HR 5.75, 95% CI 1.34-24.56), haemoglobin below 9 g/dL (HR 5.29, 95% CI 1.58-17.69) and creatinine above 1.5 mg/dL (HR 1.98, 95% CI 1.04-3.79) were independent predictors of our primary outcome. Examining laboratory parameters as continuous variables or shortening our primary outcome to include events within 90 days yielded similar results.

CONCLUSION

Serum albumin below 3 g/dL, haemoglobin below 9 g/dL and serum creatinine above 1.5 mg/dL were independent predictors of severe outcomes in hospitalised IBD patients with Clostridium difficile infection.

Clinical approach to severe Clostridium difficile infection: update for the hospital practitioner

The rising incidence of Clostridium difficile (C. difficile) infection or CDI is now a problem of pandemic proportions. The NAP1 hypervirulent strain of C. difficile is responsible for a majority of recent epidemics and the widespread use of fluoroquinolone antibiotics may have facilitated the selective proliferation of this strain. The NAP1 strain also is more likely to cause severe and fulminant colitis characterized by marked leukocytosis, renal failure, hemodynamic instability, and toxic megacolon. No single test suffices to diagnose severe CDI, instead; the clinician must rely on a combination of clinical acumen, laboratory testing, and radiologic and endoscopic modalities. Although oral vancomycin and metronidazole are considered standard therapies in the medical management of CDI, recently it has been demonstrated that vancomycin is the more effective antibiotic in cases of severe disease. Moreover, early surgical consultation is necessary in patients who do not respond to medical therapy or who demonstrate rising white blood cell counts or hemodynamic instability indicative of fulminant colitis. Subtotal colectomy with end ileostomy is the procedure of choice for fulminant colitis. When applied to select patients in a judicious and timely fashion, surgery can be a life-saving intervention. In addition to these therapeutic approaches, several investigational treatments including novel antibiotics, fecal bacteriotherapy and immunotherapy have shown promise in the care of patients with severe CDI.

Temporal trends in disease outcomes related to Clostridium difficile infection in patients with inflammatory bowel disease

BACKGROUND

Clostridium difficile has emerged as an important pathogen in patients with inflammatory bowel disease (IBD) and is associated with increased morbidity and mortality. No studies have examined the temporal change in severity of C. difficile infection (CDI) complicating IBD.

METHODS

Using data from the Nationwide Inpatient Sample, we identified all IBD-related hospitalizations during the years 1998, 2004, and 2007 and examined hospitalizations with a coexisting diagnosis of C. difficile. We compared the absolute outcomes of in-hospital mortality and colectomy in the C. difficile-IBD cohort during these timepoints, and also examined these outcomes relative to non-C. difficile IBD controls during each corresponding year.

RESULTS

During 1998, 2004, and 2007, approximately 1.4%, 2.3%, and 2.9% of all IBD hospitalizations nationwide were complicated by CDI (P < 0.001). The absolute mortality in the C. difficile-IBD cohort increased from 5.9%-7.2% (P = 0.052) with a nonsignificant increase in colectomy rate from 3.8%-4.5% between 1998 and 2007. Compared to non-C. difficile IBD controls, there was an increase in the relative mortality risk associated with C. difficile from 1998 (odds ratio [OR] 2.38, 95% confidence interval [CI]: 1.52-3.72) to 2007 (OR 3.38, 95% CI: 2.66-4.29) (P = 0.15) with a significant increase in total colectomy odds from 1998 (OR 1.39, 95% CI: 0.81-2.37) to 2007 (OR 2.51, 95% CI: 1.90-3.34) (P = 0.03).

CONCLUSION

There has been a temporal increase nationwide in CDI complicating IBD hospitalizations. The excess morbidity associated with C. difficile infection in hospitalized IBD patients has increased between 1998 and 2007.

Systematic review: Clostridium difficile and inflammatory bowel disease

BACKGROUND

There is increasing concern about the apparently rising incidence and worsening outcome of Clostridium difficile infection (CDI) associated with inflammatory bowel disease (IBD). We have systematically reviewed the literature to evaluate the incidence, risk factors, endoscopic features, treatment and outcome of CDI complicating IBD.

AIM

To systematically review: clostridium difficile & inflammatory bowel disease.

METHODS

Structured searches of Pubmed up to September 2010 for original, cross-sectional, cohort and case-controlled studies were undertaken.

RESULTS

Of 407 studies, 42 met the inclusion criteria: their heterogeneity precluded formal meta-analysis. CDI is commoner in active IBD, particularly ulcerative colitis, than in controls. Certainty about a temporal trend to its increasing incidence in IBD is compromised by possible detection bias and miscoding. Risk factors include immunosuppressants and antibiotics, the latter less commonly than in controls. Endoscopy rarely shows pseudomembranes and is unhelpful for diagnosing CDI in IBD. There are no controlled therapeutic trials of CDI in IBD. In large studies, outcome of CDI in hospitalised IBD patients appears worse than in controls.

CONCLUSIONS

The complication of IBD by Clostridium difficile infection has received increasing attention in the past decade, but whether its incidence is really increasing or its outcome worsening remains unproven. Therapeutic trials of Clostridium difficile infection in IBD are lacking and are needed urgently.

Microbial induction of immunity, inflammation, and cancer

The human microbiota presents a highly active metabolic that influences the state of health of our gastrointestinal tracts as well as our susceptibility to disease. Although much of our initial microbiota is adopted from our mothers, its final composition and diversity is determined by environmental factors. Westernization has significantly altered our microbial function. Extensive experimental and clinical evidence indicates that the westernized diet, rich in animal products and low in complex carbohydrates, plus the overuse of antibiotics and underuse of breastfeeding, leads to a heightened inflammatory potential of the microbiota. Chronic inflammation leads to the expression of certain diseases in genetically predisposed individuals. Antibiotics and a “clean” environment, termed the “hygiene hypothesis,” has been linked to the rise in allergy and inflammatory bowel disease, due to impaired beneficial bacterial exposure and education of the gut immune system, which comprises the largest immune organ within the body. The elevated risk of colon cancer is associated with the suppression of microbial fermentation and butyrate production, as butyrate provides fuel for the mucosa and is anti-inflammatory and anti-proliferative. This article will summarize the work to date highlighting the complicated and dynamic relationship between the gut microbiota and immunity, inflammation and carcinogenesis.

Clostridium difficile infection: epidemiology, risk factors and management

The epidemiology of Clostridium difficile infection (CDI) has changed over the past decade. There has been a dramatic worldwide increase in its incidence, and new CDI populations are emerging, such as those with community-acquired infection and no previous exposure to antibiotics, children, pregnant women and patients with IBD. Diagnosis of CDI requires identification of C. difficile toxin A or B in diarrheal stool. The accuracy of current diagnostic tests remains inadequate and the optimal diagnostic testing algorithm has not been defined. The first-line agents for CDI treatment are metronidazole and vancomycin, with the latter being the preferred agent in patients with severe disease as it has significantly superior efficacy. The incidence of metronidazole treatment failures has increased, emphasizing the need to find alternative treatment options. Disease recurrence continues to occur in 20-40% of patients and its treatment remains challenging. In patients with CDI who develop fulminant colitis, early surgical consultation is essential. Intravenous immunoglobulin and tigecycline have been used in patients with severe refractory disease but delaying surgery may be associated with worse outcomes. Infection control measures are key to prevent horizontal transmission of infection. Ongoing research into effective treatment protocols and prevention is essential.

Therapeutic transplantation of the distal gut microbiota

Although it is generally accepted that the distal gut microbiota are relatively stable in healthy adult individuals, a collapse of the microbial community structure resulting from antibiotic therapy or pathogen presence can lead to gut dysfunction. However, recent findings demonstrate that it is possible to engraft new microbiota from a donor source, resulting in the restoration of gut functionality and improvement in health. This builds upon decades of case reports and series in which fecal transfers were used to successfully treat refractory and recurrent Clostridium difficile infection. As fecal transplantation becomes part of mainstream medicine, it will likely provide a unique opportunity to study the interactions of humans with their attendant microbiota and allow greater insights into their synergistic functionality.

Impact of Clostridium difficile on inflammatory bowel disease

Clostridium difficile infection (CDI) has been increasing in incidence among those with underlying inflammatory bowel disease (IBD) and is associated with substantial morbidity, the need for surgery and even mortality. The similar clinical presentation between CDI and a flare of underlying IBD makes prompt diagnosis essential to prevent deterioration which would accompany an escalation of immunosuppression in the absence of appropriate antibiotic therapy. Classical risk factors (antibiotic or healthcare exposure) or clinical findings (pseudomembranes) may not be found in many IBD patients with CDI and should not be considered essential for entertaining the diagnosis. Enzyme immunoassays detecting both toxins A and B remain the most widely used test for diagnosis and have acceptable sensitivity, but may require testing of multiple samples in select situations. Both vancomycin and metronidazole appear to be effective and treatment with oral vancomycin is preferred in those with severe disease, including those who require hospitalization. Appropriate infection control measures are essential to restrict patient-to-patient spread within healthcare environments and to prevent recurrences. Several novel therapies are currently under study, including new antibiotic agents and monoclonal antibodies targeted against the toxins. There is a need to broaden these studies to the IBD population. There is also the need to prospectively examine whether CDI has long-term disease-modifying consequences in those with underlying IBD.