Clostridium difficile infection: an update on epidemiology, risk factors, and therapeutic options

Clostridioides difficile Infection in Hospitalized Patients-A Retrospective Epidemiological Study

Clostridioides difficile infection (CDI) is the main source of healthcare and antibiotic-associated diarrhea in hospital context and long-term care units, showing significant morbidity and mortality. This study aimed to analyze the epidemiological context, describing the severity and outcomes of this event in patients admitted to our hospital, thus confirming the changing global epidemiological trends in comparison with other cohorts. We conducted a single-center, observational, and retrospective study at the Hospital do Espírito Santo (HESE), Évora, in Portugal, analyzing the incidence of CDI in patients meeting eligibility criteria from January to December 2018. During this period, an annual incidence rate of 20.7 cases per 10,000 patients was documented. The studied population average age was 76.4 ± 12.9 years, 83.3% over 65. Most episodes were healthcare-acquired, all occurring in patients presenting multiple risk factors, with recent antibiotic consumption being the most common. Regarding severity, 23.3% of cases were classified as severe episodes. Recurrences affected 16.7% of participants, predominantly female patients over 80 years old, all of whom were healthcare-acquired. Mortality rate was disproportionately high among the older population. Our investigation documented an overall incidence rate of over 10.4-fold the number of cases identified in the year 2000 at the same hospital, more recently and drastically, in community-associated episodes.

Yield of Emergency Department Stool Culture Tests Among Children With Acute Gastroenteritis in Israel

Previous studies have attempted to predict a positive stool culture in pediatric patients with acute gastroenteritis (AGE), but most of them are either from developing countries or are outdated. In all, 276 patients with AGE and 560 control patients were analyzed for differences in clinical factors including the presence of fever, highest recorded temperature, bloody diarrhea, number of bowel movements in 24 hours prior to presentation, and the presence of seizures, as well as laboratory parameters including leukocyte count and C-reactive protein (CRP). Positive stool sample rate was 13.7%. The most common bacterial pathogen was Campylobacter jejuni. Bacterial AGE was significantly associated with fever >37.9°C, bloody diarrhea, higher stool passing frequency, seizures, and CRP levels. For pediatric patients who present to the emergency department with AGE and present without bloody diarrhea, fever, frequent stool passing, or seizures, a stool culture test is of poor yield and may not be necessary.

Cytotoxic synergism of Clostridioides difficile toxin B with proinflammatory cytokines in subjects with inflammatory bowel diseases

Clostridioides difficile (C. difficile) is progressively colonizing humans and animals living with humans. During this process, hypervirulent strains and mutated toxin A and B of C. difficile (TcdA and TcdB) are originating and developing. While in healthy subjects colonization by C. difficile becomes a risk after the use of antibiotics that alter the microbiome, other categories of people are more susceptible to infection and at risk of relapse, such as those with inflammatory bowel disease (IBD). Recent in vitro studies suggest that this increased susceptibility could be due to the strong cytotoxic synergism between TcdB and proinflammatory cytokines the tumor necrosis factor-alpha and interferon-gamma (CKs). Therefore, in subjects with IBD the presence of an inflammatory state in the colon could be the driver that increases the susceptibility to C. difficile infection and its progression and relapses. TcdB is internalized in the cell via three receptors: chondroitin sulphate proteoglycan 4; poliovirus receptor-like 3; and Wnt receptor frizzled family. Chondroitin sulphate proteoglycan 4 and Wnt receptor frizzled family are involved in cell death by apoptosis or necrosis depending on the concentration of TcdB and cell types, while poliovirus receptor-like 3 induces only necrosis. It is possible that cytokines could also induce a greater expression of receptors for TcdB that are more involved in necrosis than in apoptosis. Therefore, in subjects with IBD there are the conditions: (1) For greater susceptibility to C. difficile infection, such as the inflammatory state, and abnormalities of the microbiome and of the immune system; (2) for the enhancement of the cytotoxic activity of TcdB +Cks; and (3) for a greater expression of TcdB receptors stimulated by cytokines that induce cell death by necrosis rather than apoptosis. The only therapeutic approach currently possible in IBD patients is monitoring of C. difficile colonization for interventions aimed at reducing tumor necrosis factor-alpha and interferon-gamma levels when the infection begins. The future perspective is to generate bacteriophages against C. difficile for targeted therapy.

Application and development of fecal microbiota transplantation in the treatment of gastrointestinal and metabolic diseases: A review

Fecal microbiota transplantation (FMT) restores a balanced intestinal flora, which helps to cure recurrent Clostridium difficile infections (RCDI). FMT has also been used to treat other gastrointestinal diseases, including inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), and chronic constipation, as well as a variety of non-GI disorders. The purpose of this review is to discuss gut microbiota and FMT treatment of GI and non-GI diseases. An imbalanced gut microbiota is known to predispose one to Clostridium difficile infections (CDI), IBD, and IBS. However, the complex role of the gut microbiota in maintaining health is a newer concept that is being increasingly studied. The microbiome plays a major role in cellular immunity and metabolism and has been implicated in the pathogenesis of non-GI autoimmune diseases, chronic fatigue syndrome, obesity, and even some neuropsychiatric disorders. Many recent studies have reported that viral gastroenteritis can affect intestinal epithelial cells, and SARS-CoV-2 virus has been identified in the stool of infected patients. FMT is a highly effective cure for RCDI, but a better understanding of the gut microbiota in maintaining health and controlled studies of FMT in a variety of conditions are needed before FMT can be accepted and used clinically.

Cefadroxil-Induced Clostridium difficile Infection Following Total Knee Arthroplasty

Perioperative infection prophylaxis is a fundamental element of total knee arthroplasty (TKA). There has been a recent trend toward the use of extended postoperative oral antibiotics in high-risk patients. We describe a case report of a patient who underwent a primary TKA and subsequently developed Clostridium difficile colitis after an extended course of postoperative prophylactic oral cefadroxil. Following the C. difficile infection, the patient eventually developed bacteremia and a multidrug-resistant Escherichia coli prosthetic joint infection which required multiple debridements. Extended use of postoperative prophylactic oral cefadroxil may increase the risk of C. difficile-associated diarrhea. Additionally, our case suggests that C. difficile infection may subsequently increase the risk of bacteremia which could lead to prosthetic joint infection. More evidence is required to further define this risk.

The Cutting Edge of Gastroenteritis: Advances in Understanding of Enteric Infection

ABSTRACT

In recent years, multiple advances have been made in the care, diagnosis, and mechanistic understanding of acute gastroenteritis (AGE). In this review, we discuss the current state of the art of diagnosis and management, as well as how changes in practice can improve care and decrease costs. We will discuss present study demonstrating the effect of AGE on the microbiome and how that may be linked to secondary effects or long-term changes. We will explore the use of novel technologies to further our capacity to understand how gastrointestinal infections occur and promulgate. Finally, will discuss advances in our understanding of how gastrointestinal infections capacitate other changes such as post-viral motility or other post viral intestinal dysfunction.

Longitudinal Data Discontinuity in Electronic Health Records and Consequences for Medication Effectiveness Studies

Electronic health record (EHR) discontinuity (i.e., receiving care outside of the study EHR system), can lead to information bias in EHR-based real-world evidence (RWE) studies. An algorithm has been previously developed to identify patients with high EHR-continuity. We sought to assess whether applying this algorithm to patient selection for inclusion can reduce bias caused by data-discontinuity in four RWE examples. Among Medicare beneficiaries aged >=65 years from 2007 to 2014, we established 4 cohorts assessing drug effects on short-term or long-term outcomes, respectively. We linked claims data with two US EHR systems and calculated %bias of the multivariable-adjusted effect estimates based on only EHR vs. linked EHR-claims data because the linked data capture medical information recorded outside of the study EHR. Our study cohort included 77,288 patients in system 1 and 60,309 in system 2. We found the subcohort in the lowest quartile of EHR-continuity captured 72-81% of the short-term and only 21-31% of the long-term outcome events, leading to %bias of 6-99% for the short-term and 62-112% for the long-term outcome examples. This trend appeared to be more pronounced in the example using a nonuser comparison rather than an active comparison. We did not find significant treatment effect heterogeneity by EHR-continuity for most subgroups across empirical examples. In EHR-based RWE studies, investigators may consider excluding patients with low algorithm-predicted EHR-continuity as the EHR data capture relatively few of their actual outcomes, and treatment effect estimates in these patients may be unreliable.

Invisible steps for a global endemy: molecular strategies adopted by Clostridioides difficile

Clostridioides difficile infection (CDI) is on the rise worldwide and is associated with an increase in deaths and socio-health burden. C. difficile has become ubiquitous in anthropized environments because of the extreme resistance of its spores. Based on the epidemiological data and knowledge of molecular pathogenesis of C. difficile, it is possible to predict its progressive colonization of the human population for the following reasons: first, its global spread is unstoppable; second, the toxins (Tcds) produced by C. difficile, TcdA and TcdB, mainly cause cell death by apoptosis, but the surviving cells acquire a senescence state that favours persistence of C. difficile in the intestine; third, proinflammatory cytokines, tumour necrosis factor-α and interferon-γ, induced during CDI, enhance the cytotoxicity of Tcds and can increase the survival of senescent cells; fourth, Tcds block mobility and induce apoptosis in immune cells recruited at the infection site; and finally, after remission from primary infection or relapse, C. difficile causes functional abnormalities in the enteric glial cell (EGC) network that can result in irritable bowel syndrome, characterized by a latent inflammatory response that contributes to C. difficile survival and enhances the cytotoxic activity of low doses of TcdB, thus favouring further relapses. Since a 'global endemy' of C. difficile seems inevitable, it is necessary to develop an effective vaccine against Tcds for at-risk individuals, and to perform a prophylaxis/selective therapy with bacteriophages highly specific for C. difficile. We must be aware that CDI will become a global health problem in the forthcoming years, and we must be prepared to face this menace.

Clostridium difficile Infection in the Plastic Surgery Population: Lessons from the ACS NSQIP Database

Clostridium difficile-associated infections (CDI) have a significant impact on morbidity and mortality of hospitalized medical and surgical patients. There is a paucity of data regarding the incidence, impact, and modifiable risk factors in the plastic surgery population.

METHODS

The ACS NSQIP database was retrospectively queried for all cases performed by plastic surgeons during 2016. All plastic surgery cases, combined cases, demographics, and baseline clinical characteristics were extracted from the database. The study population was divided into 2 groups based on the development of CDI. Independent variables for development of CDI were identified.

RESULTS

During the study period, a total of 29,256 patients underwent a procedure by plastic surgery, with the most commonly performed procedures involving the breast (58%) and trunk (14%). Only 44 patients developed post-operative CDI (0.1%). Factors independently associated with development of CDI were wound classification at the end of the surgery, COPD, procedures involving the trunk, and surgery for reconstruction of pressure ulcers. Outpatient surgery was associated with decreased odds of developing CDI [AOR (95% CI):0.2 (0.1, 0.4), adj P < 0.001]. Staying overnight did not increase the odds of developing CDI; however, staying for >1 day in the hospital was associated with an increased risk of CDI development [AOR (95% CI): 1.03 (1.01, 1.13), adj P = 0.001]. Combined cases, ASA, body mass index, diabetes, and active smoking were not associated with CDI.

CONCLUSIONS

CDI are rare in the plastic surgery population and are most associated with trunk/decubitus ulcer reconstructions, inpatient hospital stay, and contaminated wounds. The patients that usually fit in these categories have acutely or chronically infected wounds, which are often treated with systemic antibiotics. For patient with decubitus ulcers and other trunk reconstruction, the guidelines for pre and post-operative systemic antibiotic usage is not well defined. For patients who have had trunk reconstruction, development of evidence-based antibiotic stewardship guidelines may help these patients by limiting antibiotic usage and thereby reducing the incidence of CDI.

Low prevalence of Clostridium difficile colonization in patients in long-term care facilities in Graz, Austria: A point-prevalence study

BACKGROUND

We aimed to determine the prevalence of asymptomatic colonization by C. difficile in stool of residents in four long-term care facilities (LTCFs) in Graz, Austria and to identify factors associated with colonization.

METHODS

We conducted a point-prevalence study in March 2018. Stool samples were examined by GDH enzyme immunoassay and when positive a toxin A/B-enzyme immunoassay was carried out. Additionally, all samples were tested by toxin A and B PCR and were plated manually as well as in automated fashion onto selective C. difficile agar.

RESULTS

In 4/144 (2.8%) residents the GDH assay was positive. Each resident was colonized by a different C. difficile ribotype. C. difficile was not detected in any of the environmental samples. Significantly more colonized residents (60%) had stayed at a hospital in the 3 months previous to the study compared to 10% of non-colonized patients (p=0.01).

CONCLUSIONS

The prevalence of colonization by toxigenic C. difficile was 2.8% in patients in LTCFs in Graz, Austria.

Risk of complications and mortality following recurrent and non-recurrent Clostridioides difficile infection: a retrospective observational database study in England

BACKGROUND

Clostridioides difficile infection (CDI) increases the risk of complications and mortality. We assessed the magnitude of these outcomes in a large cohort of English patients with initial and recurrent CDI.

AIM

To compare the risk of complications and all-cause mortality, within 12 months, among hospitalized patients ≥18 years old with hospital-associated- (HA-) CDI and recurrent CDI.

METHODS

Patients with HA-CDI during 2002-2013 were identified using inpatient hospital data linked to primary care and death data. Each HA-CDI case was frequency matched to two hospitalized patients without CDI on age group, sex, calendar year of admission, admission method and number of hospital care episodes. A second CDI episode starting on days 13-56 was defined as recurrence. Risks of mortality and complications at 12 months were analysed using Cox proportional hazard models.

FINDINGS

We included 6862 patients with HA-CDI and 13,724 without CDI. Median age was 81.0 years (IQR 71.0-87.0). Patients with HA-CDI had more comorbidities than those without CDI, and significantly higher risks of mortality (adjusted hazard ratio (95% confidence interval) 1.77 (1.67-1.87)) and complications (1.66 (1.46-1.88)) within 12 months from hospital admission. Of those with HA-CDI, 1140 (16.6%) experienced CDI recurrence. Patients with recurrent versus non-recurrent CDI also had significantly increased risk of mortality (1.32 (1.20-1.45)) and complications (1.37 (1.01-1.84)) in the 12 months from the initial CDI.

CONCLUSIONS

HA-CDI (versus no CDI) and recurrent CDI are both associated with significantly higher risks of complications or death within 12 months of the initial CDI episode.

Clostridium difficile infection: Is there a change in the underlying factors? Inflammatory bowel disease and Clostridium difficile

BACKGROUND / AIMS

Clostridium difficile is a Gram-positive, strict anaerobe, spore-forming bacterium. It can cause self-limiting mild diarrhea, severe diarrhea, pseudomembranous colitis, and fatal fulminant colitis. We aimed to investigate the changes in epidemiology and incidence of C. difficile infection in our hospital database.

PATIENTS AND METHODS

Episodes of C. difficile toxin were identified in hospital database, and data such as age, sex, community versus hospital acquisition, intensive care follow-up, current or previous treatments with antibiotics within the past 3 months, medication with proton pump inhibitors, or immunosuppressive therapies were collected.

RESULTS

Toxin-positive 78 individuals constituted the patient group. In univariate analyses, independent risk factors for toxin positivity were community versus hospital acquisition [odds ratio (OR), 5.49; 95% confidence interval (CI), 2.52-11.95; P = 0.0001], presence of inflammatory bowel diseases (IBDs) (OR, 21.5; 95% CI, 8.65-53.44; P = 0.0001), proton pump inhibitors' use (OR, 4.53; 95% CI, 1.97-10.43; P = 0.0001), immunosuppressive drug use (OR, 4.1; 95% CI, 2.01-8.3; P = 0.0001), and use of quinolone group of antibiotics (OR, 5.95; 95% CI, 1.92-18.46; P = 0.001). Antibiotic use was a protective risk factor (OR, 0.09; 95% CI, 0.01-0.78; P = 0.01) and presence of IBDs was an independent risk factor (OR, 6.8; 95% CI, 1.5-30.08; P = 0.01) in community-acquired group (OR, 0.09; 95% CI, 0.01-0.78; P = 0.01).

CONCLUSION

In recent studies, C. difficile infections were demonstrated to be more frequent in younger individuals who did not have a history of hospitalization but had an underlying disease such as IBD. In our study, we showed the change in the epidemiological data with prominence of underlying diseases such as IBDs.

Risk factors for Clostridioides difficile infection and colonization among patients admitted to an intensive care unit in Shanghai, China

Background

Clostridioides difficile is considered the main pathogen responsible for hospital-acquired infections. This prospective study determined the prevalence, molecular epidemiological characteristics, and risk factors for C. difficile infection (CDI) and C. difficile colonization (CDC) among patients in the intensive care unit (ICU) of a large-scale tertiary hospital in China, with the aim of providing strategies for efficient CDI and CDC prevention and control.

Methods

Stool samples were collected and anaerobically cultured for C. difficile detection. The identified isolates were examined for toxin genes and subjected to multilocus sequence typing. Patients were classified into CDI, CDC, and control groups, and their medical records were analyzed to determine the risk factors for CDI and CDC.

Results

Of the 800 patients included in the study, 33 (4.12%) and 25 (3.12%) were identified to have CDI and CDC, respectively. Associations with CDI were found for fever (OR = 13.993), metabolic disorder (OR = 7.972), and treatment with fluoroquinolone (OR = 42.696) or combined antibiotics (OR = 2.856). CDC patients were characterized by prolonged hospital stay (OR = 1.137), increased number of comorbidities (OR = 36.509), respiratory diseases (OR = 0.043), and treatment with vancomycin (OR = 18.168). Notably, treatment with metronidazole was found to be a protective factor in both groups (CDI: OR = 0.042; CDC: OR = 0.013). Eighteen sequence types (STs) were identified. In the CDI group, the isolated strains were predominantly toxin A and toxin B positive (A + B+) and the epidemic clone was genotype ST2. In the CDC group, the dominant strains were A + B+ and the epidemic clone was ST81.

Conclusions

The prevalences of CDC and CDI in our ICU were relatively high, suggesting the importance of routine screening for acquisition of C. difficile. Future prevention and treatment strategies for CDC and CDI should consider hospital stay, enteral nutrition, underlying comorbidities, and use of combined antibiotics. Moreover, metronidazole may be a protective factor for both CDI and CDC, and could be used empirically.

Drivers of Clostridioides difficile hypervirulent ribotype 027 spore germination, vegetative cell growth and toxin production in vitro

OBJECTIVES

Clostridioides difficile infection (CDI) is a considerable healthcare and economic burden worldwide. Faecal microbial transplant remains the most effective treatment for CDI, but is not at the present time the recommended standard of care. We hereby investigate which factors derived from a healthy gut microbiome might constitute the colonization resistance barrier (CRB) in the gut, inhibiting CDI.

METHODS

CRB drivers pH, short chain fatty acid (SCFA), and oxidation-reduction potential (ORP) were investigated in vitro using C. difficile NAP1/BI/027. Readouts for inhibitory mechanisms included germination, growth, toxin production and virulence gene expression. pH ranges (3-7.6), SCFA concentrations (25-200 mM) and ORP (-300 to 200 mV) were manipulated in brain heart infusion broth cultures under anaerobic conditions to assess the inhibitory action of these mechanisms.

RESULTS

A pH < 5.3 completely inhibited C. difficile growth to optical density (OD) 0.019 vs. 1.19 for control pH 7.5. Toxin production was reduced to 25 units vs. 3125 units for pH 7.6 (1 in 5 dilutions). Virulence gene expression reduced by 150-fold compared with pH 7.6 (p < 0.05). Germination and proliferation of spores below pH 6.13 yielded an average OD of 0.006 vs. 0.99 for control. SCFA were potent regulators of toxin production at 25 mM and above (p < 0.05). Acetate significantly inhibited toxin production to 25 units independent of OD (0.8733) vs. control (OD 0.6 and toxin titre 3125) (p < 0.05). ORP did not impact C. difficile growth.

CONCLUSIONS

This study highlights the critical role that pH has in the CRB, regulating CDI in vitro and that SCFA can regulate C. difficile function independent of pH.

The good bugs: the use of probiotics in pediatrics

PURPOSE OF REVIEW

There is growing evidence encouraging the use of probiotics in many conditions in children. However, given the wide number of probiotics available and contradictory data in the literature, the health-care provider is often faced with uncertainness about whether or not to use probiotics and which one(s) to choose. We here review current hypotheses regarding the efficacy and safety of probiotics and evaluate the available data on the use of probiotics in most common diseases in children. Considering that probiotics have strain-specific effects, we will focus on individual probiotic strains rather than on probiotics in general.

RECENT FINDINGS

Strain-specific efficacy was clearly demonstrated with Lactobacillus rhamnosus GG and Saccharomyces boulardii I-745 in the treatment of acute infectious diarrhea, Lactobacillus reuteri DSM 17938 in infantile colics, Lactobacillus rhamnosus GG, and VSL#3 in irritable bowel syndrome. In addition, encouraging results are seen for use of probiotics in necrotizing enterocolitis, food allergy, and nonalcoholic fatty liver disease. However, the data available for constipation are to be considered somewhat equivocal.

SUMMARY

The clinical relevance of these findings indicates that healthcare providers need to take strain-specificity and disease specificity of probiotics into consideration when recommending probiotic for their patients.

Syrian Hamster as an Animal Model for the Study on Infectious Diseases

Infectious diseases still remain one of the biggest challenges for human health. In order to gain a better understanding of the pathogenesis of infectious diseases and develop effective diagnostic tools, therapeutic agents, and preventive vaccines, a suitable animal model which can represent the characteristics of infectious is required. The Syrian hamster immune responses to infectious pathogens are similar to humans and as such, this model is advantageous for studying pathogenesis of infection including post-bacterial, viral and parasitic pathogens, along with assessing the efficacy and interactions of medications and vaccines for those pathogens. This review summarizes the current status of Syrian hamster models and their use for understanding the underlying mechanisms of pathogen infection, in addition to their use as a drug discovery platform and provides a strong rationale for the selection of Syrian hamster as animal models in biomedical research. The challenges of using Syrian hamster as an alternative animal model for the research of infectious diseases are also addressed.

Trends in Incidence and Outcomes of Clostridium difficile Colitis in Hospitalized Patients of Febrile Neutropenia: A Nationwide Analysis

INTRODUCTION

Clostridium difficile infection (CDI) has been attracting attention lately as the most common hospital acquired infection. Patients with neutropenia because of malignancy seem to be at an increased risk for developing CDI. There is currently limited data that assesses the national burden and outcomes of CDI in Febrile Neutropenia (FN).

METHODS

We analyzed the National Inpatient Sample (NIS) database for all subjects with discharge diagnosis of FN with or without CDI (ICD-9 codes 288.00, 288.03,780.60, and 008.45) as primary or secondary diagnosis during the period from 2008 to 2014. All analyses were performed with SAS, version 9.4 (SAS Institute).

RESULTS

From 2008 to 2014 there were total 19422 discharges of FN patients with CDI. There was a rising incidence of CDI in patients with FN from 4.11% (in 2008) to 5.83% (in 2014). The In-hospital mortality showed a decreasing trend from 7.79% (in 2008) to 5.32% (in 2014), likely because of improvements in diagnostics and treatment. The overall mortality (6.37% vs. 4.61%), length of stay >5 days (76.45% vs. 50.98%), hospital charges >50,000 dollars (64.43% vs. 40.29%), colectomy and colostomy (0.35% vs. 0.15%), and discharge to skilled nursing facility (10.47% vs. 6.43%) was significantly more in FN patients with CDI versus without CDI over 7 years (2008 to 2014). Age above 65 years, Hispanic race, hematological malignancies, urban hospital settings, and sepsis were significant predictors of mortality in febrile neutropenia patients with CDI.

DISCUSSION

Despite the significant decrease in mortality, the incidence of CDI is rising in hospitalized FN patients with underlying hematological malignancies. Risk factor modification, with the best possible empiric antibiotic regimen is imperative for reducing mortality and health care costs in this cohort.

The Impact of Bariatric Surgery on Short Term Risk of Clostridium Difficile Admissions

BACKGROUND AND AIMS

Clostridium difficile infection (CDI) is major health care concern with reports linking it to obesity. Our aim was to investigate the little known impact of the two most common bariatric surgeries, Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG), on risk of CDI admissions.

METHODS

This is a retrospective cohort study using the 2013 Nationwide Readmission Database. We examined inpatient CDI rates within 120 days after RYGB (n = 40,059) and VSG (n = 45,394). In a time to event analysis we also evaluated inpatient CDI rates up to 11 months post-surgery. We chose morbidly obese patients that underwent non-emergent ventral hernia repair (VHR) as additional surgical controls (n = 9673).

RESULT

CDI rates were higher after RYGB than VSG in the first 30 days (odds ratio [OR] = 2.10; 95% confidence interval [CI], 1.05-4.20) with a similar but nonsignificant trend within 31-120 days. CDI rates were also higher after RYGB compared to VHR controls within 31-120 days after surgery (OR = 3.22, 95%CI: 1.31, 7.88, p = 0.01). In a time to event analysis with up to 11 months follow up, RYGB led to higher CDI compared to VSG (hazard ratio [HR] = 1.87; 95% CI, 1.12-3.13) with a trend towards higher CDI compared to VHR (HR = 1.95; 95% CI, 0.94-4.06). Similar CDI rates occurred after VSG vs VHR.

CONCLUSIONS

RYGB may increase the risk of CDI hospitalization when compared to VSG and VHR controls. This data suggest VSG may be a better bariatric choice when post-surgical CDI risk is a concern.

Clostridium Difficile infections in patients with AML or MDS undergoing allogeneic hematopoietic stem cell transplantation identify high risk for adverse outcome

Clostridium difficile (CD) infection is the main cause of nosocomial enterocolitis in western countries and in patients undergoing allogeneic hematopoietic stem cell transplantation (alloHCT). Recipients of alloHCT are at high risk for CD infection but large studies in this population are rare and conflicting results have been reported. We analyzed 727 patients with AML or MDS undergoing alloHCT in our center from 2004 to 2015. Ninety-six patients (13%) had CD infection and 103 patients (14%) were identified as asymptomatic carriers by screening at admission and once a week during aplasia. Patients with CD infection had a shorter median overall survival of 8 months (95% CI, 6-36 months) compared with 25 months (95% CI, 17-35 months) for patients without CD infection, (HR 1.4, p = 0.04). CD positive patients were less likely to develop acute graft-versus-host disease (aGvHD; HR 0.6, p = 0.004) compared with CD-negative patients, but did not show differences in gastrointestinal aGvHD (HR 0.9, p = 0.5). Symptomatic patients developed gastrointestinal aGvHD (HR 2.5, p = 0.02) more often compared with asymptomatic CD positive patients. This analysis demonstrates a high prevalence for CD infection in patients undergoing alloHCT. A significant lower overall survival for patients with CD infection could be demonstrated.

Proteotyping of Clostridioides difficile as Alternate Typing Method to Ribotyping Is Able to Distinguish the Ribotypes RT027 and RT176 From Other Ribotypes

Clostridioides difficile, a Gram-positive spore-forming bacterium, is the leading cause of nosocomial diarrhea worldwide and therefore a substantial burden to the healthcare system. During the past decade, hypervirulent PCR-ribotypes (RT) e.g., RT027 or RT176 emerged rapidly all over the world, associated with both, increased severity and mortality rates. It is thus of great importance to identify epidemic strains such as RT027 and RT176 as fast as possible. While commonly used diagnostic methods, e.g., multilocus sequence typing (MLST) or PCR-ribotyping, are time-consuming, proteotyping offers a fast, inexpensive, and reliable alternative solution. In this study, we established a MALDI-TOF-based typing scheme for C. difficile. A total of 109 ribotyped strains representative for five MLST clades were analyzed by MALDI-TOF. MLST, based on whole genome sequences, and PCR-ribotyping were used as reference methods. Isoforms of MS-detectable biomarkers, typically ribosomal proteins, were related with the deduced amino acid sequences and added to the C. difficile proteotyping scheme. In total, we were able to associate nine biomarkers with their encoding genes and include them in our proteotyping scheme. The discriminatory capacity of the C. difficile proteotyping scheme was mainly based on isoforms of L28-M (2 main isoforms), L35-M (4 main isoforms), and S20-M (2 main isoforms) giving rise to at least 16 proteotyping-derived types. In our test population, five of these 16 proteotyping-derived types were detected. These five proteotyping-derived types did not correspond exactly to the included five MLST-based C. difficile clades, nevertheless the subtyping depth of both methods was equivalent. Most importantly, proteotyping-derived clade B contained only isolates of the hypervirulent RT027 and RT176. Proteotyping is a stable and easy-to-perform intraspecies typing method and a promising alternative to currently used molecular techniques. It is possible to distinguish the group of RT027 and RT176 isolates from non-RT027/non-RT176 isolates using proteotyping, providing a valuable diagnostic tool.

Virulence of new variant strains of Clostridium difficile producing only toxin A or binary toxin in the hamster model

Pathogenesis of Clostridium difficile has been linked to production of toxins, including the large toxins A and B as well as the binary toxin CDT. Until recently, toxin A was only found in combination in clinical strains with the toxin B, unlike toxin B or CDT, which were found alone in toxigenic variants. New toxigenic variants of C. difficile detected in our laboratory from patients with diarrhoea or severe colitis, including a variant producing only toxin A, were tested for virulence in the hamster model, which displays the clinical features of C. difficile disease. Hamsters infected with a strain producing only toxin B induced similar clinical signs, time to death from infection and histologic damage compared to the hypervirulent strain 027. No mortality or clinical signs of infection but caecal histologic damage was found with the variant producing only toxin A. The C. difficile variant strain producing only CDT was able to kill one hamster out of seven; nevertheless, the surviving animals had few alteration of the caecum.

Differential effects of Clostridium difficile toxins on ion secretion and cell integrity in human intestinal cells

BACKGROUND

Toxin A (TcdA), toxin B (TcdB), and binary toxin (CDT) produced by Clostridium difficile (CD) are thought to play a key role in inducing diarrhea. The aim of this study was to investigate the individual and combined roles of CD toxins in inducing enterotoxic and cytotoxic effect.

METHODS

Ion secretion and epithelial damage were evaluated in the Ussing chambers as measure of enterotoxic or cytotoxic effect, respectively, in human-derived intestinal cells.

RESULTS

When added to the mucosal side of Caco-2 cells, TcdB, but not TcdA, induced ion secretion and its effects increased in the presence of TcdA. CDT also induced ion secretion when added to either the mucosal or serosal compartment. Serosal addition of TcdB induced epithelial damage consistent with its cytotoxic effect. However, mucosal addition of TcdB had similar effects, but only in the presence of TcdA. CDT induced epithelial damage when added to the serosal side of cell monolayers, and this was associated with a late onset but prolonged effect. All data were replicated using human colon biopsies.

CONCLUSIONS

These data indicate that CD, through the combined and direct activity of its three toxins, induces integrated and synergic enterotoxic and cytotoxic effects on the intestinal epithelium.

Dual role of the colonization factor CD2831 in Clostridium difficile pathogenesis

Clostridium difficile is a Gram-positive, anaerobic bacterium and the leading cause of antibiotic-associated diarrhea and pseudomembranous colitis. C. difficile modulates its transition from a motile to a sessile lifestyle through a mechanism of riboswitches regulated by cyclic diguanosine monophosphate (c-di-GMP). Previously described as a sortase substrate positively regulated by c-di-GMP, CD2831 was predicted to be a collagen-binding protein and thus potentially involved in sessility. By overexpressing CD2831 in C. difficile and heterologously expressing it on the surface of Lactococcus lactis, here we further demonstrated that CD2831 is a collagen-binding protein, able to bind to immobilized collagen types I, III and V as well as native collagen produced by human fibroblasts. We also observed that the overexpression of CD2831 raises the ability to form biofilm on abiotic surface in both C. difficile and L. lactis. Notably, we showed that CD2831 binds to the collagen-like domain of the human complement component C1q, suggesting a role in preventing complement cascade activation via the classical pathway. This functional characterization places CD2831 in the Microbial Surface Components Recognizing Adhesive Matrix Molecule (MSCRAMMs) family, a class of virulence factors with a dual role in adhesion to collagen-rich tissues and in host immune evasion by binding to human complement components.

Epithelium-specific MyD88 signaling, but not DCs or macrophages, control acute intestinal infection with Clostridium difficile

Infection with Clostridium difficile is one of the major causes of health care acquired diarrhea and colitis. Signaling though MyD88 downstream of TLRs is critical for initiating the early protective host response in mouse models of C. difficile infection (CDI). In the intestine, MyD88 is expressed in various tissues and cell types, such as the intestinal epithelium and mononuclear phagocytes (MNP), including DC or macrophages. Using a genetic gain-of-function system, we demonstrate here that restricting functional MyD88 signaling to the intestinal epithelium, but also to MNPs is sufficient to protect mice during acute CDI by upregulation of the intestinal barrier function and recruitment of neutrophils. Nevertheless, we also show that mice depleted for CD11c-expressing MNPs in the intestine display no major defects in mounting an effective inflammatory response, indicating that the absence of these cells is irrelevant for inducing host protection during acute infection. Together, our results highlight the importance of epithelial-specific MyD88 signaling and demonstrate that although functional MyD88 signaling in DC and macrophages alone is sufficient to correct the phenotype of MyD88-deficiency, these cells do not seem to be essential for host protection in MyD88-sufficient animals during acute infection with C. difficile.

Faecal microbiota transplantation for Clostridium difficile infection using a lyophilized inoculum from non-related donors: A case series involving 19 patients

Faecal microbiota transplantation (FMT) has been reported to be effective in treating relapsing of refractory Clostridium difficile infections, although some practical barriers are limiting its widespread use. In this study, our objective was to evaluate the rate of resolution of diarrhea following administration of lyophilized and resolved FMT via a nasogastric (NG) tube. We recruited 19 patients suffered from laboratory-confirmed C. difficile infection. Each of them was treated by lyophilized and resolved inoculum through a NG tube. One participant succumbed following the procedure due to unrelated diseases. Out of 18 cases, 15 patients reportedly experienced a resolution of the symptoms. One patient was treated with another course of antibiotics, and two of the non-responders were successfully retreated with another course of FMT utilizing a lyophilized inoculum. Notably, no significant adverse activities were observed. In accordance to our clinical experiences, a patient will likely benefit from FMT treatment including lyophilized inoculum.

2019 update of the WSES guidelines for management of Clostridioides (Clostridium) difficile infection in surgical patients

In the last three decades, Clostridium difficile infection (CDI) has increased in incidence and severity in many countries worldwide. The increase in CDI incidence has been particularly apparent among surgical patients. Therefore, prevention of CDI and optimization of management in the surgical patient are paramount. An international multidisciplinary panel of experts from the World Society of Emergency Surgery (WSES) updated its guidelines for management of CDI in surgical patients according to the most recent available literature. The update includes recent changes introduced in the management of this infection.

The role of a sequencing-based clinical intestinal screening test in patients at high-risk for Clostridium difficile and other pathogens: a case report

BACKGROUND

Hospitalization and antibiotic treatment can put patients at high risk for Clostridium difficile infection, where a disturbance of the gut microbiome allows for Clostridium difficile proliferation and associated symptoms, including mild, moderate, or severe diarrhea. Clostridium difficile infection is challenging to treat, often recurrent, and leads to almost 30,000 annual deaths in the USA alone. Here we present a case where SmartGut™, an at-home, self-administered sequencing-based clinical intestinal screening test, was used to identify the presence of Clostridium difficile in a patient with worsening diarrhea. Identification of this pathogen and subsequent treatment led to a significant improvement in symptoms.

CASE PRESENTATION

The patient is a 29-year-old white woman with a history of severe irritable bowel syndrome with diarrhea, hemorrhoidectomy, and anal sphincterotomy complicated by a perianal fistula and perirectal abscesses that required extended courses of broad-spectrum antibiotics. In June 2016, she developed intermittent Clostridium difficile infections, which required continued antibiotic use. Months later she used an at-home, self-administered, intestinal microbial test, the first of which was negative for the presence of Clostridium difficile, but it detected the relative abundance of microbes associated with irritable bowel syndrome outside the healthy reference ranges. In the subsequent 2 months after the negative Clostridium difficile result, her gastrointestinal symptoms worsened dramatically. A second microbiome test resulted in a positive Clostridium difficile finding and continued abnormal microbial parameters, which led the treating physician to refer her to a gastroenterologist. Additional testing confirmed the presence of Clostridium difficile with a toxin-positive strain. She received treatment immediately and her gastrointestinal symptoms improved significantly over the next week.

CONCLUSIONS

This case report suggests that more frequent DNA testing for Clostridium difficile infections may be indicated in patients that are at high-risk for Clostridium difficile infection, especially for patients with irritable bowel syndrome, and those who undergo gastrointestinal surgery and/or an extended antibiotic treatment. This report also shows that such testing could be effectively performed using at-home, self-administered sequencing-based clinical intestinal microbial screening tests. Further research is needed to investigate whether the observations reported here extrapolate to a larger cohort of patients.

[Clostridium difficile-associated deaths from 2013-2016 in Munich and Nuremberg : Reporting behavior and patient characteristics]

BACKGROUND

A number of risk factors for C. difficile infection (CDI) are described in the literature, in particular an antibiotic therapy 4-6 weeks before disease, an age of >65 years, immunosuppression and living in a long-term care facility. Increasing incidence rates have been reported for Germany. CDI is the fourth most common nosocomial infection with 6.4%.

AIM

Due to the amendment of the Infection Protection Act of 01.05.2016, the proportion of all deaths that are C. difficile-associated deaths should be investigated to determine the extent to which the obligation to report is fulfilled in the case of a severe CDI. The epidemiological situation in Munich and Nuremberg should also be investigated and the characteristics of the deceased should be analyzed.

MATERIAL AND METHODS

A review of all death certificates for the period from 1 January 2013 to 30 June 2016 was carried out according to defined inclusion criteria for clostridia infection. All data were anonymized, standardized and statistically evaluated.

RESULTS

Almost every hundredth death is associated with C. difficile. Medical and outbreak reports are very poor and do not reflect the real situation. The age of the deceased and increased factors for the acquisition of a CDI correspond to the literature. The collected data from both cities show a good congruence.

CONCLUSION

For the first time, data from the health authorities can be submitted on the proportion of all deaths that are C. difficile-associated deaths, reporting behavior and patient characteristics in cases of severe CDI. This is a serious disease, especially for older people with regard to the existence of risk factors, and its frequency and effects are significantly underestimated.

Intrinsic Class D β-Lactamases of Clostridium difficile

Clostridium difficile is the causative agent of the deadly C. difficile infection. Resistance of the pathogen to β-lactam antibiotics plays a major role in the development of the disease, but the mechanism of resistance is currently unknown. We discovered that C. difficile encodes class D β-lactamases, i.e., CDDs, which are intrinsic to this species. We studied two CDD enzymes, CDD-1 and CDD-2, and showed that they display broad-spectrum, high catalytic efficiency against various β-lactam antibiotics, including penicillins and expanded-spectrum cephalosporins. We demonstrated that the cdd genes are poorly expressed under the control of their own promoters and contribute only partially to the observed resistance to β-lactams. However, when the cdd1 gene was expressed under the control of efficient promoters in the antibiotic-sensitive Clostridium cochlearium strain, it produced high-level resistance to β-lactams. Taken together, the results determined in this work demonstrate the existence in C. difficile of intrinsic class D β-lactamases which constitute a reservoir of highly potent enzymes capable of conferring broad-spectrum, clinically relevant levels of resistance to β-lactam antibiotics. This discovery is a significant contribution to elucidation of the mechanism(s) of resistance of the clinically important pathogen C. difficile to β-lactam antibiotics.IMPORTANCEC. difficile is a spore-forming anaerobic bacterium which causes infection of the large intestine with high mortality rates. The C. difficile infection is difficult to prevent and treat, as the pathogen is resistant to many antimicrobial agents. Prolonged use of β-lactam antibiotics for treatment of various infectious diseases triggers the infection, as these drugs suppress the abundance of protective gut bacteria, allowing the resistant C. difficile bacteria to multiply. While resistance of C. difficile to β-lactam antibiotics plays the major role in the development of the disease, the mechanism of resistance is unknown. The significance of our research is in the discovery in C. difficile of β-lactamases, enzymes that destroy β-lactam antibiotics. These findings ultimately can help to combat deadly C. difficile infections.

Protective Effect of Pediococcus pentosaceus LI05 Against Clostridium difficile Infection in a Mouse Model

Clostridium difficile infection (CDI) is a major cause of infectious diarrhea among hospitalized patients. Probiotics could be instrumental in restoring the intestinal dysbiosis caused by CDI. Here, we examined the protective effect of Pediococcus pentosaceus LI05 in a mouse CDI model. C57BL/6 mice were administrated P. pentosaceus LI05 (LI05 group) or sterile anaerobic PBS (CDI group) everyday for 14 days. Mice were exposed to antibiotics cocktail for 5 days; then challenged with C. difficile strain VPI10463. Mice were monitored daily for survival and weight loss. Colonic tissue and serum samples were assessed for intestinal histopathology, intestinal barrier function and systemic inflammation. The oral administration of P. pentosaceus LI05 improved the survival rate and alleviated the histopathological impact of C. difficile. Compared to the CDI group, the levels of inflammatory mediators in the colon as well as inflammatory cytokines and chemokines in serum were substantially attenuated in the LI05 group. P. pentosaceus LI05 alleviated the CDI-induced of disruption of ZO-1, occludin and claudin-1. Additionally, fecal microbiome analysis showed an enrichment in the abundance of the Porphyromonadaceae and Rikenellaceae, while, the relative abundance of Enterobacteriaceae were decreased. Our results demonstrated that the preventive effect of P. pentosaceus LI05 against CDI was mediated via improving tight junction proteins and down-regulating the inflammatory response. Therefore, P. pentosaceus LI05 could be a promising probiotic in CDI.

Clostridium difficile-related hospitalizations and risk factors for in-hospital mortality in Spain between 2001 and 2015

AIMS

To examine trends in the incidence, characteristics and in-hospital outcomes of Clostridium difficile infection (CDI) hospitalizations from 2001 to 2015, to compare clinical variables among patients according to the diagnosis position (primary or secondary) of CDI, and to identify factors associated with in-hospital mortality (IHM).

METHODS

A retrospective study was performed using the Spanish National Hospital Discharge Database, 2001-2015. The study population included patients who had CDI as the primary or secondary diagnosis in their discharge report. Annual hospitalization rates were calculated and trends were assessed using Poisson regression models and Jointpoint analysis. Multi-variate logistic regression models were performed to identify variables associated with IHM.

FINDINGS

In total, 49,347 hospital discharges were identified (52.31% females, 33.69% with CDI as the primary diagnosis). The rate of hospitalization increased from 3.9 cases per 100,000 inhabitants in 2001-2003 to 12.97 cases per 100,000 inhabitants in 2013-2015. Severity of CDI and mean cost per patient increased from 6.36% and 3750.11€ to 11.19% and 4340.91€, respectively, while IHM decreased from 12.66% to 10.66%. Age, Charlson Comorbidity Index, severity, length of hospital stay and mean cost were significantly higher in patients with a primary diagnosis of CDI. Irrespective of the CDI diagnosis position, IHM was associated with male sex, older age, comorbidities, readmission and severity of CDI. Primary diagnosis of CDI was associated with lower IHM (odds ratio 0.60; 95% confidence interval 0.56-0.65).

CONCLUSION

CDI-related hospitalization rates are increasing, leading to a high cost burden, although IHM has decreased in recent years. Factors associated with IHM should be considered in strategies for the prevention and management of CDI.

Prolonged Mechanical Ventilation Assistance Interacts Synergistically with Carbapenem for Clostridium difficile Infection in Critically Ill Patients

Objectives: Interactions between mechanical ventilation (MV) and carbapenem interventions were investigated for the risk of Clostridium difficile infection (CDI) in critically ill patients undergoing concurrent carbapenem therapy. Methods: Taiwan’s National Intensive Care Unit Database (NICUD) was used in this analytical, observational, and retrospective study. We analyzed 267,871 intubated patients in subgroups based on the duration of MV support: 7–14 days (n = 97,525), 15–21 days (n = 52,068), 22–28 days (n = 35,264), and 29–60 days (n = 70,021). The primary outcome was CDI. Results: Age (>75 years old), prolonged MV assistance (>21 days), carbapenem therapy (>15 days), and high comorbidity scores were identified as independent risk factors for developing CDI. CDI risk increased with longer MV support. The highest rate of CDI was in the MV 29–60 days subgroup (adjusted hazard ratio (AHR) = 2.85; 95% confidence interval (CI) = 1.46–5.58; p < 0.02). Moreover, higher CDI rates correlated with the interaction between MV and carbapenem interventions; these CDI risks were increased in the MV 15–21 days (AHR = 2.58; 95% CI = 1.12–5.91) and MV 29–60 days (AHR = 4.63; 95% CI = 1.14–10.03) subgroups than in the non-MV and non-carbapenem subgroups. Conclusions: Both MV support and carbapenem interventions significantly increase the risk that critically ill patients will develop CDI. Moreover, prolonged MV support and carbapenem therapy synergistically induce CDI. These findings provide new insights into the role of MV support in the development of CDI.

Outcomes of Clostridium difficile-suspected diarrhea in a French university hospital

Clostridium difficile infection (CDI) produces a variety of clinical presentations ranging from mild diarrhea to severe infection with fulminant colitis, septic shock, and death. CDI puts a heavy burden on healthcare systems due to increased morbidity and mortality, and higher costs. We evaluated the clinical impact of CDI in terms of complications and mortality in a French university hospital compared with patients with diarrhea unrelated to CDI. A 3-year prospective, observational, cohort study was conducted in a French university hospital. Inpatients aged 18 years or older with CDI-suspected diarrhea were eligible to participate in the study and were followed for up to 60 days after CDI testing. Among the 945 patients with diarrhea included, 233 had confirmed CDI. Overall, 106 patients (11.2%) developed at least one of the following complications: colectomy, colitis, ileitis/rectitis, ileus, intestinal perforation, megacolon, multiorgan failure, pancolitis, peritonitis, pseudomembranous colitis, renal failure, and sepsis/septic shock. The complication rate was significantly higher in patients with diarrhea related to C. difficile than in non-CDI patients (26.6% vs 6.2%, P < 0.001). At day 60, 137 (14.5%) patients had died, with 37 deaths among the CDI group (15.9%). Death was attributable to CDI in 15 patients (6.4%). Complications are more frequent among CDI cases than in patients with diarrhea not related to C. difficile. Assessment of CDI is necessary to ensure allocation of sufficient resources to CDI prevention.

Diarreia causada por Clostridium difficile: recentes avanços

A infecção causada por Clostridium difficile (C. difficile), um dos agentes causadores de diarréia aguda e recorrente, tem como principal fator de risco o uso de antimicrobianos. Recentemente, houve um aumento da incidência e da mortalidade desta afecção. Clinicamente, a mesma pode manifestar-se desde um quadro de diarreia aquosa leve até a forma grave de colite pseudomembranosa. O objetivo deste artigo é apontar as mudanças epidemiológicas da infecção pelo C. difficile, além de rever fatores de risco, manifestações clínicas, métodos diagnósticos, tratamento e prevenção desta infecção. O aumento na gravidade da infecção causada pelo C. difficile é relacionado a uma nova cepa hipervirulenta, BI/NAPI/Ribotipo 027, que apresenta maior capacidade de produção de toxinas.  Essa nova cepa, mais virulenta, ainda não foi detectada no Brasil, porém como já foi identificada em outros países da América, alerta para a preocupante capacidade de disseminação universal. Essa revisão é baseada em artigos publicados nos últimos 10 anos, utilizando como base de dados o PubMed e o Scielo (Scientific Eletronic Library Online), com as palavras-chave: Epidemiologia, diarreia, Clostridium difficile e cepa hipervirulenta.

HMW-profiling using MALDI-TOF MS: A screening method for outbreaks of Clostridioides difficile

Clostridioides difficile (CD), previously known as Clostridium difficile, is an anaerobic Gram-positive rod-shaped bacterium that causes mild to severe diarrhea mainly in hospitalized patients. The bacteria are easily spread between patients and can persist in hospital wards due to its ability to form spores. An outbreak of CD causes great sufferings for patients and is in many aspects very expensive for the health care organization. Continuously monitoring circulating CD isolates in the hospital as well as being able to detect possible spread between patients at an early phase would be of great benefit. Recently a new method was published by Rizzardi et al. (2015) where CD can be typed to a High Molecular Weight (HMW)-profile using Matrix-Assisted Laser Desorption Ionization -Time of Flight Mass Spectrometry (MALDI-TOF MS). We analyzed 1000 isolates of toxin-positive CD with this method and compared the frequency of profiles within different hospitals as well as between two counties in the south-east part of Sweden. During the study period we could detect three outbreaks of CD in three different hospitals. One was an outbreak of CD with ribotype 027, resulting in severe consequences. The method was easily implemented at the clinical microbiology routine diagnostic laboratory and in collaboration with the hospitals Infection Control Units it is a very useful and cost-effective tool to detect outbreaks of CD at an early stage.

Secular trends in the epidemiology of Clostridium difficile infection (CDI) at a tertiary care hospital in Barcelona, 2006-2015: A prospective observational study

OBJECTIVE

Describe secular trends in the epidemiology and outcome of Clostridium difficile infection (CDI) at a tertiary hospital.

METHODS

All consecutive primary CDI episodes in adults (January 2006-December 2015) were included. CDI was diagnosed on the presence of diarrhoea and a positive stool test for C. difficile toxin A and/or B. To define trends, a time-series analysis was performed using yearly data on demographics, clinical characteristics, management, antimicrobial treatment, and outcome of CDI. Patients were followed-up for three months after the diagnosis.

RESULTS

There were 724 CDI episodes. Over the period from 2006 to 2015, the incidence rose from 0.18 episodes/1000 admissions to 0.26 episodes (relative rate [RR] 1.43; 95%CI, 1.02-2.00; P = 0.035). Median Charlson comorbidity index increased from 2 (IQR 1-3) to 4 (IQR 2-4) (RR 1.65; 95%CI, 1.12-2.41; P = 0.005). Overall, 80.4% of patients received proton pump inhibitors (PPIs) prior to CDI, and the percentage of PPI discontinuations rose from 2.3% to 20.4% (RR 8.80; 95%CI 1.20-64.36; P = 0.006). Management of non-Clostridium antibiotics also changed: antibiotic withdrawals or switches increased from 4.2% to 29.2% (RR 7.00; 95%CI 1.68-29.15, P = 0.001). Regarding CDI treatment, the percentage of patients treated with metronidazole decreased (88.9% vs 52.6%) (RR 0.59 (0.48-0.73), P < 0.001), whereas the percentage receiving vancomycin increased (1.9% vs 32.6%) (RR 17.62 (2.47-125.49), P < 0.001). The percentages of cures, deaths, and first recurrences did not significantly change over the 10-year period.

CONCLUSIONS

Changes in CDI management were associated with a stable prognosis (percentage of cures and first recurrences), even though affected patients had a greater number of comorbidities over time.

Clostridium difficile - From Colonization to Infection

Clostridium difficile is the most frequent cause of nosocomial antibiotic-associated diarrhea. The incidence of C. difficile infection (CDI) has been rising worldwide with subsequent increases in morbidity, mortality, and health care costs. Asymptomatic colonization with C. difficile is common and a high prevalence has been found in specific cohorts, e.g., hospitalized patients, adults in nursing homes and in infants. However, the risk of infection with C. difficile differs significantly between these cohorts. While CDI is a clear indication for therapy, colonization with C. difficile is not believed to be a direct precursor for CDI and therefore does not require treatment. Antibiotic therapy causes alterations of the intestinal microbial composition, enabling C. difficile colonization and consecutive toxin production leading to disruption of the colonic epithelial cells. Clinical symptoms of CDI range from mild diarrhea to potentially life-threatening conditions like pseudomembranous colitis or toxic megacolon. While antibiotics are still the treatment of choice for CDI, new therapies have emerged in recent years such as antibodies against C. difficile toxin B and fecal microbial transfer (FMT). This specific therapy for CDI underscores the role of the indigenous bacterial composition in the prevention of the disease in healthy individuals and its role in the pathogenesis after alteration by antibiotic treatment. In addition to the pathogenesis of CDI, this review focuses on the colonization of C. difficile in the human gut and factors promoting CDI.

Antibiotic treatment of acute gastroenteritis in children

Antibiotic therapy is not necessary for acute diarrhea in children, as rehydration is the key treatment and symptoms resolve generally without specific therapy. Searching for the etiology of gastroenteritis is not usually needed; however, it may be necessary if antimicrobial treatment is considered. The latter is left to the physician evaluation in the absence of clear indications. Antimicrobial treatment should be considered in severely sick children, in those who have chronic conditions or specific risk factors or in specific settings. Traveler’s diarrhea, prolonged diarrhea, and antibiotic-associated diarrhea may also require antibiotic therapy. Depending on the severity of symptoms or based on risk of spreading, empiric therapy may be started while awaiting the results of microbiological investigations. The choice of antibiotic depends on suspected agents, host conditions, and local epidemiology. In most cases, empiric therapy should be started while awaiting such results. Empiric therapy may be started with oral co-trimoxazole or metronidazole, but in severe cases parenteral treatment with ceftriaxone or ciprofloxacin might be considered.

Clostridium difficile - From Colonization to Infection

Clostridium difficile is the most frequent cause of nosocomial antibiotic-associated diarrhea. The incidence of C. difficile infection (CDI) has been rising worldwide with subsequent increases in morbidity, mortality, and health care costs. Asymptomatic colonization with C. difficile is common and a high prevalence has been found in specific cohorts, e.g., hospitalized patients, adults in nursing homes and in infants. However, the risk of infection with C. difficile differs significantly between these cohorts. While CDI is a clear indication for therapy, colonization with C. difficile is not believed to be a direct precursor for CDI and therefore does not require treatment. Antibiotic therapy causes alterations of the intestinal microbial composition, enabling C. difficile colonization and consecutive toxin production leading to disruption of the colonic epithelial cells. Clinical symptoms of CDI range from mild diarrhea to potentially life-threatening conditions like pseudomembranous colitis or toxic megacolon. While antibiotics are still the treatment of choice for CDI, new therapies have emerged in recent years such as antibodies against C. difficile toxin B and fecal microbial transfer (FMT). This specific therapy for CDI underscores the role of the indigenous bacterial composition in the prevention of the disease in healthy individuals and its role in the pathogenesis after alteration by antibiotic treatment. In addition to the pathogenesis of CDI, this review focuses on the colonization of C. difficile in the human gut and factors promoting CDI.

[Efficacy of real-time PCR for detecting Clostridium difficile infection: comparison with enzyme-linked fluorescent spectroscopy-based approaches]

OBJECTIVE

To evaluate the diagnostic efficacy of real?time polymerase chain reaction (q?PCR) for Clostridium difficile infection (CDI) in comparison with routine culture and enzyme?linked fluorescent spectroscopy?based aprroaches.

METHODS

Stool samples were collected from suspected CDI cases in General Hospital of Guangzhou Military Command of PLA between May and December in 2016. All the samples were examined with 3 methods, namely enzyme?linked fluorescent spectroscopy for detecting Clostridium difficile toxin A/B (CDAB), detection of glutamate dehydrogenase (GDH), and q?PCR for amplification of Clostridium difficile?specific gene tpi and toxin gene (tcdA/tcdB), with the results of fecal culture as the reference for evaluating the diagnostic efficacy of the 3 methods.

RESULTS

Of the total of 70 fecal samples, 13 (18.57%) were found to be positive for Clostridium difficile, including toxin?producing strains in 6 (8.57%) samples. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic coincidence rate of q?PCR for tpi were 92.31%, 91.23%, 70.59%, 98.11% and 91.43%, respectively, which were significantly higher than those of GDH test (84.62%, 84.21%, 55.00%, 96.00%, and 84.29%, respectively; Χ²=24.881, P<0.001). The sensitivity of q?PCR for tcdA/cdB was significantly higher than that of enzyme?linked fluorescent spectroscopy for CDAB in detecting CDI (66.67% vs 33.33%; Χ²=35.918, P<0.001).

CONCLUSION

Both CDAB detection and q?PCR have a high specificity in detecting CDI, but GDH detection has a good sensitivity, and all these 3 methods have a high negative predictive value. Compared with other detection methods, amplification of tpi and tcdA/tcdB using q?PCR allows more rapid, sensitive and specific detection of CDI.

Prevalence of Clostridium difficile infection and colonization in a tertiary hospital and elderly community of North-Eastern Peninsular Malaysia

Little is known about Clostridium difficile infection (CDI) in Asia. The aims of our study were to explore (i) the prevalence, risk factors and molecular epidemiology of CDI and colonization in a tertiary academic hospital in North-Eastern Peninsular Malaysia; (ii) the rate of carriage of C. difficile among the elderly in the region; (iii) the awareness level of this infection among the hospital staffs and students. For stool samples collected from hospital inpatients with diarrhea (n = 76) and healthy community members (n = 138), C. difficile antigen and toxins were tested by enzyme immunoassay. Stool samples were subsequently analyzed by culture and molecular detection of toxin genes, and PCR ribotyping of isolates. To examine awareness among hospital staff and students, participants were asked to complete a self-administered questionnaire. For the hospital and community studies, the prevalence of non-toxigenic C. difficile colonization was 16% and 2%, respectively. The prevalence of CDI among hospital inpatients with diarrhea was 13%. Out of 22 C. difficile strains from hospital inpatients, the toxigenic ribotypes 043 and 017 were most common (both 14%). In univariate analysis, C. difficile colonization in hospital inpatients was significantly associated with greater duration of hospitalization and use of penicillin (both P < 0·05). Absence of these factors was a possible reason for low colonization in the community. Only 3% of 154 respondents answered all questions correctly in the awareness survey. C. difficile colonization is prevalent in a Malaysian hospital setting but not in the elderly community with little or no contact with hospitals. Awareness of CDI is alarmingly poor.

Point-prevalence survey of healthcare facility-onset healthcare-associated Clostridium difficile infection in Greek hospitals outside the intensive care unit: The C. DEFINE study

BACKGROUND

The correlation of Clostridium difficile infection (CDI) with in-hospital morbidity is important in hospital settings where broad-spectrum antimicrobial agents are routinely used, such as in Greece. The C. DEFINE study aimed to assess point-prevalence of CDI in Greece during two study periods in 2013.

METHODS

There were two study periods consisting of a single day in March and another in October 2013. Stool samples from all patients hospitalized outside the ICU aged ≥18 years old with diarrhea on each day in 21 and 25 hospitals, respectively, were tested for CDI. Samples were tested for the presence of glutamate dehydrogenase antigen (GDH) and toxins A/B of C. difficile; samples positive for GDH and negative for toxins were further tested by culture and PCR for the presence of toxin genes. An analysis was performed to identify potential risk factors for CDI among patients with diarrhea.

RESULTS

5,536 and 6,523 patients were screened during the first and second study periods, respectively. The respective point-prevalence of CDI in all patients was 5.6 and 3.9 per 10,000 patient bed-days whereas the proportion of CDI among patients with diarrhea was 17% and 14.3%. Logistic regression analysis revealed that solid tumor malignancy [odds ratio (OR) 2.69, 95% confidence interval (CI): 1.18-6.15, p = 0.019] and antimicrobial administration (OR 3.61, 95% CI: 1.03-12.76, p = 0.045) were independent risk factors for CDI development. Charlson's Comorbidity Index (CCI) >6 was also found as a risk factor of marginal statistical significance (OR 2.24, 95% CI: 0.98-5.10). Median time to CDI from hospital admission was shorter with the presence of solid tumor malignancy (3 vs 5 days; p = 0.002) and of CCI >6 (4 vs 6 days, p = 0.009).

CONCLUSIONS

The point-prevalence of CDI in Greek hospitals was consistent among cases of diarrhea over a 6-month period. Major risk factors were antimicrobial use, solid tumor malignancy and a CCI score >6.

Clostridium difficile flagella induce a pro-inflammatory response in intestinal epithelium of mice in cooperation with toxins

Clostridium difficile is the most important enteropathogen involved in gut nosocomial post-antibiotic infections. The emergence of hypervirulent strains has contributed to increased mortality and morbidity of CDI. The C. difficile toxins contribute directly to CDI-associated lesions of the gut, but other bacterial factors are needed for the bacteria to adhere and colonize the intestinal epithelium. The C. difficile flagella, which confer motility and chemotaxis for successful intestinal colonization, could play an additional role in bacterial pathogenesis by contributing to the inflammatory response of the host and mucosal injury. Indeed, by activating the TLR5, flagella can elicit activation of the MAPK and NF-κB cascades of cell signaling, leading to the secretion of pro-inflammatory cytokines. In the current study, we demonstrate, by using an animal model of CDI, a synergic effect of flagella and toxins in eliciting an inflammatory mucosal response. In this model, the absence of flagella dramatically decreases the degree of mucosal inflammation in mice and the sole presence of toxins without flagella was not enough to elicit epithelial lesions. These results highlight the important role of C. difficile flagella in eliciting mucosal lesions as long as the toxins exert their action on the epithelium.

Recurrent Clostridium difficile Infection in Children: Patient Risk Factors and Markers of Intestinal Inflammation

BACKGROUND

The management of Clostridium difficile infection (CDI) in children is complicated by recurrence rates of 20%-30%. The identification of risk factors associated with recurrent disease might allow early recognition of those children at highest risk.

METHODS

Pediatric patients with CDI were identified through clinical laboratory records at 2 tertiary-care children's hospitals from March 2013 through May 2014. Subjects were enrolled and followed for 60 days to assess for recurrent CDI (rCDI). Blood samples were obtained at enrollment to evaluate host interleukin (IL)-8 polymorphisms and anti-toxin A antibody levels; stool samples were obtained for inflammatory markers (lactoferrin, calprotectin, IL-8) and C. difficile ribotype 027 strain status. Thirty days post enrollment, another serum sample was obtained to compare antibody responses.

RESULTS

Of the 28 pediatric patients enrolled, 27 completed follow-up and 8 (30%) experienced rCDI. At enrollment, children with malignancy had significantly lower stool calprotectin, lactoferrin and IL-8 than those without malignancy. There was a trend toward increased stool inflammatory markers in those who later developed rCDI. The IL-8 A/A genotype was not associated with recurrent disease. No patients were found to have ribotype 027 or an antibody increase to toxin A.

CONCLUSIONS

The rate of rCDI in our pediatric cohort was 30%. Children with rCDI had a trend toward higher fecal inflammatory markers with the initial infection, and these values were lower in children with malignancy. Fecal lactoferrin, calprotectin and IL-8 should be further studied to determine their value in predicting the risk of rCDI in children.