Clinical impact of Clostridium difficile colonization

Single-Centre Retrospective Audit of Clostridium difficile Infections Post Ileostomy Reversal

Background Clostridium difficile (C. difficile) infection can have serious implications on patient outcomes, especially post ileostomy reversal. The symptoms can range from asymptomatic/mild to severe, with significant morbidity or mortality. Thus far, no study has been published to determine the role and impact of preoperative C. difficile testing prior to ileostomy reversal. The aim of this audit was to identify risk factors for the development of post-ileostomy reversal C. difficile infection and provide further improvements and direction for future research. Methods All patients undergoing ileostomy reversal at the General Surgery Department at Sir Charles Gairdner Hospital, a tertiary centre in Perth, Western Australia, were retrospectively identified between January 2019 and June 2021. Demographics and key data points, such as specific types of antibiotic usage, were extracted from patient notes and analysed using IBM SPSS Statistics for Windows, version 27 (released 2020; IBM Corp., Armonk, New York, United States). Results Sixty-nine patients were identified in the audit period, with 8.70% of patients testing positive for C. difficile infection post ileostomy reversal. At the index ileostomy formation operation, postoperative use of quinolone antibiotics was statistically associated with an increased risk of developing C. difficile on ileostomy reversal (odds ratio (OR) = 15.25, confidence interval (CI) 95%, p = 0.035). Intraoperative nitroimidazole use was statistically associated with a reduced risk of C. difficile infection on ileostomy reversal (OR = 0.16, CI 95%, p = 0.045). Patients who had diverticulitis as their underlying disease pathology were 10 times more likely to develop C. difficile infection post ileostomy reversal, although this finding was not statistically significant in our study. Conclusion Several risk factors were identified, such as the use of quinolone antibiotics or having underlying diverticulitis as causes for ileostomy formation. The results from this audit provides further direction in designing further research studies into the role and impact of C. difficile testing and treatment in the perioperative period around ileostomy reversal.

Animal and In Vitro Models as Powerful Tools to Decipher the Effects of Enteric Pathogens on the Human Gut Microbiota

Examining the interplay between intestinal pathogens and the gut microbiota is crucial to fully comprehend the pathogenic role of enteropathogens and their broader impact on human health. Valid alternatives to human studies have been introduced in laboratory practice to evaluate the effects of infectious agents on the gut microbiota, thereby exploring their translational implications in intestinal functionality and overall health. Different animal species are currently used as valuable models for intestinal infections. In addition, considering the recent advances in bioengineering, futuristic in vitro models resembling the intestinal environment are also available for this purpose. In this review, the impact of the main human enteropathogens (i.e., Clostridioides difficile, Campylobacter jejuni, diarrheagenic Escherichia coli, non-typhoidal Salmonella enterica, Shigella flexneri and Shigella sonnei, Vibrio cholerae, and Bacillus cereus) on intestinal microbial communities is summarized, with specific emphasis on results derived from investigations employing animal and in vitro models.

Prevention and treatment of C. difficile in cancer patients

PURPOSE OF REVIEW

We provide an update on the recent literature on Clostridioides difficile infection (CDI) in cancer patients.

RECENT FINDINGS

Distinguishing between colonization and infection remains challenging in cancer patients. Many patients with negative toxin analysis are still treated for CDI, and some meet criteria for severe cases. The incidence of CDI is high in cancer patients, especially those with haematological malignancies. Disruption of the gut microbiome due to antibiotic consumption, chemotherapy and radiotherapy is the primary factor contributing to CDI development. The severity of CDI in cancer patients is often unclear due to the absence of well-defined severity criteria. Certain microbiome species predominance and specific ribotypes have been associated with worse outcomes. Whole genome sequencing could be helpful for differentiating recurrence from reinfection and exploring potential nosocomial transmission. While certain new drugs such as fidaxomicin or bezlotoxumab show promise, the optimal treatment and prevention strategies for CDI in cancer patients remain uncertain. Faecal microbiota transplantation (FMT) holds potential for reducing CDI recurrence rates.

SUMMARY

Further studies are needed to provide robust recommendations for diagnosis, grading severity, and therapeutic management of CDI in cancer patients. Recurrences are particularly concerning due to subsequent exposition to CDI risk factors.

Depletion of butyrate-producing microbes of the Firmicutes predicts nonresponse to FMT therapy in patients with recurrent Clostridium difficile infection

Approximately 10% of individuals diagnosed with Clostridium difficile infection (CDI) show the resistance to fecal microbiota transplantation (FMT), with the underlying mechanisms remaining elusive. Deciphering the intricate microbiome profile within this particular subset of FMT-refractory patients via clinical FMT investigations assumes paramount importance, as it holds the key to designing targeted therapeutic interventions tailored for CDI, particularly recurrent CDI (rCDI). A cohort of twenty-three patients afflicted with rCDI, exhibiting congruent clinical baselines, was meticulously selected for FMT. Rigorous screening of thousands of healthy individuals identified ten FMT donors who met stringent health standards, while a total of 171 stool samples were collected to serve as healthy controls. To assess the influence of microbiome dynamics on FMT efficacy, fecal samples were collected from four donors over a continuous period of twenty-five weeks. After FMT treatment, seven individuals exhibited an inadequate response to FMT. These non-remission patients displayed a significant reduction in α-diversity indexes. Meanwhile, prior to FMT, the abundance of key butyrate-producing Firmicutes bacteria, including Christensenellaceae_R_7_group, Ruminococcaceae_unclassified, Coprococcus_2, Fusicatenibacter, Oscillospira, and Roseburia, were depleted in non-remission patients. Moreover, Burkholderiales_unclassified, Coprococcus_2, and Oscillospira failed to colonize non-remission patients both pre- and post-treatment. Conversely, patients with a favorable FMT response exhibited a higher relative abundance of Veillonella prior to treatment, whereas its depletion was commonly observed in non-remission individuals. Genera interactions in lower effectiveness FMT donors were more similar to those in non-remission patients, and Burkholderiales_unclassified, Coprococcus_2, and Oscillospira were frequently depleted in these lower effectiveness donors. Older patients were not conducive to the colonization of Veillonella, consistent with their poor prognosis after FMT. FMT non-remission rCDI patients exhibited distinct characteristics that hindered the colonization of beneficial butyrate-producing Firmicutes microbes. These findings hold promise in advancing the precision of FMT therapy for rCDI patients.

Post-Discharge Clostridioides difficile Infection after Arthroplasties in Poland, Infection Prevention and Control as the Key Element of Prevention of C. difficile Infections

Clostridioides difficile is still one of the most common causes of hospital-acquired infectious diarrhea (CDI), and the incidence of CDI is one of the indicators that allows conclusions to be derived on the correctness of antibiotic administration. The objective of this observational study was the analysis of post-discharge CDI incidence in patients undergoing hip or knee arthroplasty, in order to specify optimum conditions for the surgical procedures and outpatient postoperative care. One-year observational study. Public Polish hospitals. Retrospective records for 83,525 surgery patients having undergone hip or knee arthroplasty were extracted from the Polish National Health Fund databases. CDI and/or antibiotic prescriptions in the 30 day post-surgery period were expressed per 1000 surgeries with antibiotic prescription on discharge or in ambulatory care, respectively. The CDI incidence rate was 34.4 per 10,000 patients, and 7.7 cases per 100,000 post-surgery patient-days. Patients who were prescribed at least one antibiotic were diagnosed with CDI more often than patients who had no antibiotic treatment (55.0/1000 patients vs. 1.8/1000 patients). In the multifactorial analysis, the following factors were significant: being at least 65 years of age, trauma as the cause of surgery, length of stay over 7 days, HAIs other than CDI and taking beta-lactams and/or quinolones but not macrolides in the post-discharge period. Postoperative antibiotic prescription in patients undergoing joint replacement surgery is the main risk factor for CDI. These observations indicate the necessity of improvement of infection control programs as the key factor for CDI prevention.

Risk Factors Associated With Clostridium difficile-Associated Diarrhea

Introduction: Recent years have been alarming due to the sudden, dramatic rise in the incidence of Clostridium difficile infection (CDI). Identifying and addressing the risk factors associated with CDI will help in reducing the incidence of infection and associated complications.

Methods: This case-control study was conducted in a tertiary care hospital in Pakistan from June 2020 to March 2021, in which 200 patients diagnosed with Clostridium difficile-associated diarrhea (CDAD) were enrolled in the study. CDAD was diagnosed based on clinical symptoms and stool enzyme immunoassay. Another 200 participants without a diagnosis of CDAD were enrolled from the outpatient department as a control group. Participants were enrolled after seeking informed consent.

Results: In patients older than 65, risk of CDI was higher compared to participants lower than 65 years old (15.5% vs. 8.0%; p value: 0.02). Hospitalization (25.5% vs. 6.0%; p value < 0.0001), the use of proton pump inhibitors in last 30 days (23.0% vs. 10.5%; p value: 0.001) , and use of antibiotics in the last 30 days (36.0% vs. 10.5%; p value < 0.0001) were significantly higher in participants with CDI.

Conclusion: Hospitalization, the usage of proton pump inhibitors, and antibiotics in the last 30 days were significantly associated with CDI. A higher incidence of CDI was associated with risk factors like increased body mass index, diabetes, chronic kidney disease, and malignancy.

Clostridioides difficile infection in liver cirrhosis patients: A population-based study in United States

BACKGROUND

Clostridioides (formerly Clostridium) difficile infection (CDI) is an increasingly frequent cause of morbidity and mortality in hospitalized patients. Multiple risk factors are documented in the literature that includes, but are not limited to, antibiotics use, advanced age, and gastric acid suppression. Several epidemiological studies have reported an increased incidence of CDI in advanced liver disease patients. Some have also demonstrated a higher prevalence of nosocomial infections in cirrhotic patients.

AIM

To use a large nationwide database, we sought to determine CDI’s risk among liver cirrhosis patients in the United States.

METHODS

We queried a commercial database (Explorys Inc^TM, Cleveland, OH, United States), and obtained an aggregate of electronic health record data from 26 major integrated United States healthcare systems comprising 360 hospitals in the United States from 2018 to 2021. Diagnoses were organized into the Systematized Nomenclature of Medicine Clinical Terms (SNOMED–CT) hierarchy. Statistical analysis for the multivariable model was performed using Statistical Package for Social Sciences (SPSS version 25, IBM Corp^TM). For all analyses, a two-sided P value of < 0.05 was considered statistically significant.

RESULTS

There were a total of 19387760 patients in the database who were above 20 years of age between the years 2018-2021. Of those, 133400 were diagnosed with liver cirrhosis. The prevalence of CDI amongst the liver cirrhosis population was 134.93 per 100.000 vs 19.06 per 100.000 in non-cirrhotic patients (P < 0.0001). The multivariate analysis model uncovered that cirrhotic patients were more likely to develop CDI (OR: 1.857; 95%CI: 1.665-2.113, P < 0.0001) compared to those without any prior history of liver cirrhosis.

CONCLUSION

In this large database study, we uncovered that cirrhotic patients have a significantly higher CDI prevalence than those without cirrhosis. Liver cirrhosis may be an independent risk factor for CDI. Further prospective studies are needed to clarify this possible risk association that may lead to the implementation of screening methods in this high-risk population.

SARS-CoV-2 identified by transmission electron microscopy in lymphoproliferative and ischaemic intestinal lesions of COVID-19 patients with acute abdominal pain: two case reports

Background

SARS-CoV-2 may produce intestinal symptoms that are generally mild, with a small percentage of patients developing more severe symptoms. The involvement of SARS-CoV-2 in the physiopathology of bowel damage is poorly known. Transmission electron microscopy (TEM) is a useful tool that provides an understanding of SARS-CoV-2 invasiveness, replication and dissemination in body cells but information outside the respiratory tract is very limited. We report two cases of severe intestinal complications (intestinal lymphoma and ischaemic colitis) in which the presence of SARS-CoV-2 in intestinal tissue was confirmed by TEM. These are the first two cases reported in the literature of persistence of SARS-CoV-2 demonstrated by TEM in intestinal tissue after COVID 19 recovery and SARS-CoV-2 nasopharyngeal clearance.

Case presentation

During the first pandemic peak (1st March–30th April 2020) 932 patients were admitted in Hospital Universitari Mútua Terrassa due to COVID-19, 41 (4.4%) required cross-sectional imaging techniques to assess severe abdominal pain and six of them (0.64%) required surgical resection. SARS-CoV-2 in bowel tissue was demonstrated by TEM in two of these patients. The first case presented as an ileocaecal inflammatory mass which turned to be a B-cell lymphoma. Viral particles were found in the cytoplasm of endothelial cells of damaged mucosa. In situ hybridization was negative in tumour cells, thus ruling out an oncogenic role for the virus. SARS-CoV-2 remained in intestinal tissue 6 months after nasopharyngeal clearance, suggesting latent infection. The second patient had a severe ischaemic colitis with perforation and SARS-CoV-2 was also identified in endothelial cells.

Conclusions

Severe intestinal complications associated with COVID-19 are uncommon. SARS-CoV-2 was identified by TEM in two cases, suggesting a causal role in bowel damage.

Drug use evaluation of cefepime at Khartoum North Teaching Hospital in Sudan

BACKGROUND

Cefepime is essentially used for life-threatening infections. Although overutilisation of antibiotics is strongly discouraged around the world, they are still overused in developing countries including Sudan.

OBJECTIVES

This study aims to evaluate the rational use of cefepime at Khartoum North Teaching Hospital-Sudan.

METHODS

A retrospective cross-sectional, hospital-based study was conducted in the internal medicine ward at Khartoum North Teaching Hospital from August/2018 to April/2019. The study covered medical records of adult patients receiving cefepime during the study period. Patient's data were analysed using simple descriptive statistics (frequency and percentage) and inferential statistics (logistic regression) to describe the relationship between dependent and independent variables. P ≤ .05 was considered statistically significant.

RESULTS

Out of 90 patients, only 16.7% of patients were tested for antibiotic sensitivity. Cefepime was prescribed to 50% and 23.3% of patients for the treatment of UTIs/post-dialysis and sepsis, respectively. Although the majority of patients (72.2%) received cefepime with appropriate indication, only 21.1% and 15.6% received the drug with appropriate dose and duration, respectively. Cefepime had been prescribed appropriately in a correct dose, duration, and indications for only 7.8% of patients. The vast majority of patients tested for kidney functions had elevated creatinine levels (96.1%); however, cefepime dose had been adjusted for only 4.1% of them.

CONCLUSION

This study highlighted the irrational use of cefepime regarding inappropriate dose, duration, and inadequate antibiotic sensitivity tests. A lack of attention to dosage adjustment in patients with renal impairment had been observed. Positive clinical outcome was significantly associated with antibiotic sensitivity test.

Colonisation Factor CD0873, an Attractive Oral Vaccine Candidate against Clostridioides difficile

Clostridioides difficile is the main cause of health-care-associated infectious diarrhoea. Toxins, TcdA and TcdB, secreted by this bacterium damage colonic epithelial cells and in severe cases this culminates in pseudomembranous colitis, toxic megacolon and death. Vaccines in human trials have focused exclusively on the parenteral administration of toxin-based formulations. These vaccines promote toxin-neutralising serum antibodies but fail to confer protection from infection in the gut. An effective route to immunise against gut pathogens and stimulate a protective mucosal antibody response (secretory immunoglobulin A, IgA) at the infection site is the oral route. Additionally, oral immunisation generates systemic antibodies (IgG). Using this route, two different antigens were tested in the hamster model: The colonisation factor CD0873 and a TcdB fragment. Animals immunised with CD0873 generated a significantly higher titre of sIgA in intestinal fluid and IgG in serum compared to naive animals, which significantly inhibited the adherence of C. difficile to Caco-2 cells. Following challenge with a hypervirulent isolate, the CD0873-immunised group showed a mean increase of 80% in time to experimental endpoint compared to naïve animals. Survival and body condition correlated with bacterial clearance and reduced pathology in the cecum. Our findings advocate CD0873 as a promising oral vaccine candidate against C. difficile.

The impact of intensive staff education on rate of Clostridium difficile-associated disease in hospitalized geriatric patients

BACKGROUND

Toxin-producing Clostridium difficile is the most common cause of nosocomial diarrhea in geriatric units.

AIM

The purpose of study was to check the impact of intensive staff education on rate of Clostridium difficile-associated disease in hospitalized geriatric patients.

METHODS

The sampling frame was all patients suffering from diarrhea checked for Clostridium difficile toxin during the years 2017-2018. Clostridium difficile-positive patients were compared to a similar number of Clostridium difficile toxin-negative patients. The data were compared to our previous study, followed by medical staff's educational program for Clostridium difficile control and prevention.

RESULTS

Among 217 patients with diarrhea, 60 (27.6%) were positive for Clostridium difficile toxin. The study group tended to be of older age (p = 0.06), and showed higher rate of functional impairment (p < 0.001) and mortality (p < 0.001) than Clostridium difficile toxin negative patients. The rate of Clostridium difficile toxin-positive patients did not significantly differ between the previous and current studies (20.0% and 27.6%, respectively).

CONCLUSIONS AND DISCUSSION

In spite of findings, that patients tended to be older, with high rate of mortality, the rate of Clostridium difficile did not change from the previous study.

Decreased Expression of the High Mobility Group Box 1 (HMGB1) Gene in Peripheral Blood in Patients with Mild or Moderate Clostridioides difficile Infection

Cytokines are mediators of inflammation induced in the course of Clostridioides difficile infection (CDI). High Mobility Group Box 1 (HMGB1) is a cytokine playing an important role in the pathogenesis of numerous inflammatory and autoimmune diseases. The aim of the study was to assess the HMGB1 gene expression in the course of CDI. We have performed a prospective case-control study- including 55 adult patients, among them 27 with CDI, who were hospitalized from October 2018 to February 2020 and 28 healthy volunteers. We assessed: a complete blood count with differential leukocyte count, blood creatinine, albumin, and C-reactive protein (CRP) levels. Then, the expression of the HMGB1 gene was evaluated using quantitative Real-Time PCR. Patients with CDI were found to have a significant increase in white blood cells (WBC), neutrophil count, and CRP levels, they also exhibited decreased levels of albumin compared with controls. The HMGB1 gene expression was significantly lower among patients with CDI compared with the control group and significantly, inversely correlated with CRP level in blood. In conclusion, we have observed a decreased expression of the HMGB1 gene in peripheral blood of patients with mild or moderate CDI, which hypothetically could reflect their diminished capability to fight the pathogen.

Effects of proton pump inhibitor use on risk of Clostridium difficile infection: a hospital cohort study

BACKGROUND

Although there are several studies on the association between use of proton pump inhibitors (PPIs) and increased Clostridium difficile infection (CDI) risk, detailed studies analyzing the effects of PPI use on CDI risk are lacking. The present study investigated the association of the dose, duration, and types of PPIs with CDI risk.

METHODS

A single-center, cohort study was conducted on patients admitted to a hospital. The exposed cohort comprised patients who were prescribed PPIs at least once during the study period, and a control cohort was prepared by randomly assigning an index date to patients who did not use PPIs ensuring the same distribution of index dates as in the exposed cohort and matching sex, age, hospitalization period, and date of admission.

RESULTS

PPI use increased the risk of CDI by 1.8-fold [95% confidence interval (CI) 1.5-2.2]. CDI risk increased by 1.8-fold with esomeprazole (95% CI 1.4-2.2) and 2.0-fold with pantoprazole (95% CI 1.5-2.8). Patients who used a high dose had a higher risk than those who used a medium dose [adjusted hazard ratio (HR) 2.0 vs 1.3]. The risk of CDI increased 4.2-fold when the PPI exposure period was 6 days or shorter than 6 days.

CONCLUSIONS

Our study showed that PPI use was associated with an increased risk of developing CDI and the risk of CDI was dose dependent. Therefore, PPIs should only be used at proper doses and only for the necessary indications to avoid CDI risk.

Clostridium difficile infection: review

Clostridium difficile (C. difficile) is a Gram-positive, spore-forming, anaerobic bacillus, which is widely distributed in the intestinal tract of humans and animals and in the environment. In the last decade, the frequency and severity of C. difficile infection has been increasing worldwide to become one of the most common hospital-acquired infections. Transmission of this pathogen occurs by the fecal-oral route and the most important risk factors include antibiotic therapy, old age, and hospital or nursing home stay. The clinical picture is diverse and ranges from asymptomatic carrier status, through various degrees of diarrhea, to the most severe, life threatening colitis resulting with death. Diagnosis is based on direct detection of C. difficile toxins in feces, most commonly with the use of EIA assay, but no single test is suitable as a stand-alone test confirming CDI. Antibiotics of choice are vancomycin, fidaxomicin, and metronidazole, though metronidazole is considered as inferior. The goal of this review is to update physicians on current scientific knowledge of C. difficile infection, focusing also on fecal microbiota transplantation which is a promising therapy.

Retrospective analysis of Clostridium difficile infection in patients with ulcerative colitis in a tertiary hospital in China

BACKGROUND

Many reports have documented the increasing impact of Clostridium difficile infection (CDI) in patients with ulcerative colitis (UC). We conducted a retrospective study to determine the incidence, clinical characteristics, risk factors and prognosis of CDI in patients with UC.

METHODS

We studied patients with UC, hospitalized between January 2010 and December 2015 in a tertiary hospital in China. Stool samples were tested for C. difficile toxins A and B (CDAB) by enzyme immunoassays in UC patients with disease flare. CDI in UC patients was diagnosed by clinical symptoms and positive CDAB test, and each case was matched with CDAB-negative patients in a 1:2 ratio. Univariate and binary logistic regression analyses were used to measure the differences between patients with and without CDI.

RESULTS

Thirty-four (8.92%) of 381 patients with UC were CDAB positive. Antibiotic exposure within 3 months prior to the study (P = 0.004), hospitalization within 1 month prior to the study (P = 0.025), systemic use of steroids (P = 0.002) and active cytomegalovirus (CMV) infection (P = 0.001) were higher in CDI than non-CDI patients. Binary logistic regression analysis revealed that CMV infection was associated with CDI (odds ratio = 13.502, 95% confidence interval 1.307-139.512, P = 0.029). UC patients with C. difficile and CMV co-infection had more severe colonoscopic features.

CONCLUSIONS

Recent use of antibiotics, prior hospitalization and systemic use of steroids increased the risk of CDI. CMV infection was an independent risk factor of CDI in patients with UC.

New Insights into Clostridium difficile (CD) Infection in Latin America: Novel Description of Toxigenic Profiles of Diarrhea-Associated to CD in Bogotá, Colombia

Clostridium difficile (CD) produces antibiotic associated diarrhea and leads to a broad range of diseases. The source of CD infection (CDI) acquisition and toxigenic profile are factors determining the impact of CD. This study aimed at detecting healthcare facility onset- (HCFO) and community-onset (CO) CDI and describing their toxigenic profiles in Bogotá, Colombia. A total of 217 fecal samples from patients suffering diarrhea were simultaneously submitted to two CDI detection strategies: (i) in vitro culture using selective chromogenic medium (SCM; chromID, bioMérieux), followed verification by colony screening (VCS), and (ii) molecular detection targeting constitutive genes, using two conventional PCR tests (conv.PCR) (conv.16S y conv.gdh) and a quantitative test (qPCR.16s). The CD toxigenic profile identified by any molecular test was described using 6 tests independently for describing PaLoc and CdtLoc organization. High overall CDI frequencies were found by both SCM (52.1%) and conv.PCR (45.6% for conv.16S and 42.4% for conv.gdh), compared to reductions of up to half the frequency by VCS (27.2%) or qPCR.16S (22.6%). Infection frequencies were higher for SCM and conv.16S regarding HCFO but greater for CO concerning conv.gdh, such differences being statistically significant. Heterogeneous toxigenic profiles were found, including amplification with lok1/3 primers simultaneously with other PaLoc markers (tcdA, tcdB or tcdC). These findings correspond the first report regarding the differential detection of CDI using in vitro culture and molecular detection tests in Colombia, the circulation of CD having heterogeneous toxigenic profiles and molecular arrays which could affect the impact of CDI epidemiology.

Clostridium difficile colonization in preoperative colorectal cancer patients

The entire process of Clostridium difficile colonization to infection develops in large intestine. However, the real colonization pattern of C. difficile in preoperative colorectal cancer patients has not been studied. In this study, 33 C. difficile strains (16.1%) were isolated from stool samples of 205 preoperative colorectal cancer patients. C. difficile colonization rates in lymph node metastasis patients (22.3%) were significantly higher than lymph node negative patients (10.8%) (OR=2.314, 95%CI=1.023-5.235, P =0.025). Meanwhile, patients positive for stool occult blood had lower C. difficile colonization rates than negative patients (11.5% vs. 24.0%, OR=0.300, 95%CI=0.131-0.685, P =0.019). A total of 16 sequence types were revealed by multilocus sequence typing. Minimum spanning tree and time-space cluster analysis indicated that all C. difficile isolates were epidemiologically unrelated. Antibiotic susceptibility testing showed all isolates were susceptible to vancomycin and metronidazole. The results suggested that the prevalence of C. difficile colonization is high in preoperative colorectal cancer patients, and the colonization is not acquired in the hospital. Since lymph node metastasis colorectal cancer patients inevitably require adjuvant chemotherapy and C. difficile infection may halt the ongoing treatment, the call for sustained monitoring of C. difficile in those patients is apparently urgent.

Gleaning Insights from Fecal Microbiota Transplantation and Probiotic Studies for the Rational Design of Combination Microbial Therapies

Beneficial microorganisms hold promise for the treatment of numerous gastrointestinal diseases. The transfer of whole microbiota via fecal transplantation has already been shown to ameliorate the severity of diseases such as Clostridium difficile infection, inflammatory bowel disease, and others. However, the exact mechanisms of fecal microbiota transplant efficacy and the particular strains conferring this benefit are still unclear. Rationally designed combinations of microbial preparations may enable more efficient and effective treatment approaches tailored to particular diseases. Here we use an infectious disease, C. difficile infection, and an inflammatory disorder, the inflammatory bowel disease ulcerative colitis, as examples to facilitate the discussion of how microbial therapy might be rationally designed for specific gastrointestinal diseases. Fecal microbiota transplantation has already shown some efficacy in the treatment of both these disorders; detailed comparisons of studies evaluating commensal and probiotic organisms in the context of these disparate gastrointestinal diseases may shed light on potential protective mechanisms and elucidate how future microbial therapies can be tailored to particular diseases.

Antimicrobial susceptibility of Clostridium difficile isolates from ICU colonized patients revealed alert to ST-37 (RT 017) isolates

Seventy Clostridium difficile isolates from ICU colonized patients were tested for antimicrobial susceptibility and screened for resistance determinants. We found that multilocus sequence type 37 (ribotype 017) toxin A-negative/B-positive isolates were more likely resistant to moxifloxacin than toxin A-positive/B-positive isolates (41.7% versus 9.3%) with major variations in both GyrA (Thr82Ile) and GyrB (Ser366Ala), suggesting that the use of quinolone should be more strictly regulated.

Asymptomatic Carriers Contribute to Nosocomial Clostridium difficile Infection: A Cohort Study of 4508 Patients

BACKGROUND & AIMS

Nosocomial infections with Clostridium difficile present a considerable problem despite numerous attempts by health care workers to reduce risk of transmission. Asymptomatic carriers of C difficile can spread their infection to other patients. We investigated the effects of asymptomatic carriers on nosocomial C difficile infections.

METHODS

We performed a population-based prospective cohort study at 2 university hospitals in Denmark, screening all patients for toxigenic C difficile in the intestine upon admittance, from October 1, 2012, to January 31, 2013. Screening results were blinded to patients, staff, and researchers. Patients were followed during their hospital stay by daily registration of wards and patient rooms. The primary outcomes were rate of C difficile infection in exposed and unexposed patients and factors associated with transmission.

RESULTS

C difficile infection was detected in 2.6% of patients not exposed to carriers and in 4.6% of patients exposed to asymptomatic carriers at the ward level (odds ratio for infection if exposed to carrier, 1.79; 95% confidence interval, 1.16-2.76). Amount of exposure correlated with risk of C difficile infection, from 2.2% in the lowest quartile to 4.2% in the highest quartile of exposed patients (P = .026). Combining the load of exposure to carriers and length of stay seemed to have an additive effect on the risk of contracting C difficile.

CONCLUSIONS

In a population-based prospective cohort study in Denmark, we found that asymptomatic carriers of toxigenic C difficile in hospitals increase risk of infection in other patients.

Current knowledge on the laboratory diagnosis of Clostridium difficile infection

Clostridium difficile (C. difficile) is a spore-forming, toxin-producing, gram-positive anaerobic bacterium that is the principal etiologic agent of antibiotic-associated diarrhea. Infection with C. difficile (CDI) is characterized by diarrhea in clinical syndromes that vary from self-limited to mild or severe. Since its initial recognition as the causative agent of pseudomembranous colitis, C. difficile has spread around the world. CDI is one of the most common healthcare-associated infections and a significant cause of morbidity and mortality among older adult hospitalized patients. Due to extensive antibiotic usage, the number of CDIs has increased. Diagnosis of CDI is often difficult and has a substantial impact on the management of patients with the disease, mainly with regards to antibiotic management. The diagnosis of CDI is primarily based on the clinical signs and symptoms and is only confirmed by laboratory testing. Despite the high burden of CDI and the increasing interest in the disease, episodes of CDI are often misdiagnosed. The reasons for misdiagnosis are the lack of clinical suspicion or the use of inappropriate tests. The proper diagnosis of CDI reduces transmission, prevents inadequate or unnecessary treatments, and assures best antibiotic treatment. We review the options for the laboratory diagnosis of CDI within the settings of the most accepted guidelines for CDI diagnosis, treatment, and prevention of CDI.

Effect of Metronidazole in Infants with Bowel Habit Change: Irrelative to the Clostridium difficile Colonization

PURPOSE

Clinical symptoms associated with Clostridium difficile infection (CDI) can vary widely. Carrier state without apparent symptoms is relatively common during infancy. The objective of this study was to determine the association of C. difficile colonization with bowel habit change and the effect of C. difficile colonization treatment on restoration of normal bowel habit.

METHODS

Between 2006 and 2014, infants at 1 to 12 months of age with diarrhea for more than 2 weeks who did not improve with conservative care were recruited from Gachon University Gil Medical Center. Infants who were followed up for at least 7 days were included. The presence or absence of C. difficile colonization, effect of metronidazole, and other medical records were reviewed. To determine the association between CDI and bowel habit change, logistic regression analysis was used.

RESULTS

Of a total of 126 infants, 74 (58.7%) were male patients. Of the 126 patients, 27 (21.4%) had C. difficile colonization. Significant (p<0.05) risk factors for C. difficile colonization included artificial milk feeding (odds ratio [OR], 4.310; 95% confidence interval [CI], 1.564-11.878), prior rotavirus vaccination (OR, 4.322; 95% CI, 1.018-18.349), and antibiotic use (OR, 4.798; 95% CI, 1.430-16.101). There was improvement in bowel habit after metronidazole therapy (OR, 0.34; 95% CI, 0.15-0.79; p<0.05), regardless of the presence or absence of C. difficile colonization.

CONCLUSION

There was no significant correlation between bowel habit change and C. difficile colonization during infancy. However, metronidazole can be used as an optional method to manage functional gastrointestinal disorders.

Asymptomatic and yet C. difficile-toxin positive? Prevalence and risk factors of carriers of toxigenic Clostridium difficile among geriatric in-patients

Background

Clostridium difficile infections (CDI) are the most frequent cause of diarrhoea in hospitals. Geriatric patients are more often affected by the condition, by a relapse and complications. Therefore, a crucial question is how often colonization with toxigenic Clostridium difficile strains occurs in elderly patients without diarrhoea and whether there is a “risk pattern” of colonized patients that can be defined by geriatric assessment. Furthermore, the probability for those asymptomatic carriers to develop a symptomatic infection over time has not been sufficiently explored.

Methods

We performed a cohort study design to assess the association of clinical variables with Clostridium difficile colonization. The first stool sample of 262 consecutive asymptomatic patients admitted to a geriatric unit was tested for toxigenic Clostridium difficile using PCR (GeneXpert, Cepheid). A comprehensive geriatric assessment (CGA) including Barthel Index, Mini Mental State Examination (MMSE) and hand grip-strength was performed. In addition, Charlson Comorbidity Index, body mass index, number and length of previous hospital stays, previous treatment with antibiotics, institutionalization, primary diagnoses and medication were recorded and evaluated as possible risk factors of colonization by means of binary logistic regression. Secondly, we explored the association of C. difficile colonization with subsequent development of CDI during hospital stay.

Results

At admission, 43 (16.4%) patients tested positive for toxin B by PCR. Seven (16.3%) of these colonized patients developed clinical CDI during hospital stay, compared to one out of 219 patients with negative or invalid PCR testing (Odds ratio 12,3; Fisher’s exact test: p = 0.000). Overall, 7 out of 8 (87.5%) CDI patients had been colonized at admission. Risk factors of colonization with C. difficile were a history of CDI, previous antibiotic treatment and hospital stays. The parameters of the CGA were not significantly associated with colonization.

Conclusion

Colonization with toxigenic Clostridium difficile strains occurs frequently in asymptomatic patients admitted to a geriatric unit. Previous CDI, antibiotic exposure and hospital stay, but not clinical variables such as CGA, are the main factors associated with asymptomatic Clostridium difficile carriage. Colonization is a crucial risk factor for subsequent development of symptomatic CDI.

Colonization of toxigenic Clostridium difficile among ICU patients: a prospective study

BACKGROUND

A prospective study was performed to investigate the prevalence of colonization among ICU patients and to examine whether asymptomatic carriers were the source of subsequent C. difficile infection (CDI) and acquisition of toxigenic C. difficile.

METHODS

Rectal swabs were collected from adult patients on admission to and at discharge from a 50-bed medical ICU of a major referral hospital in western China, from August to November 2014. Stools were collected from patients who developed ICU-onset diarrhea. Both swabs and stools were screened for tcdB (toxin B gene) by PCR. Samples positive to tcdB were cultured for C. difficile and isolates recovered were screened for tcdB and the binary toxin genes by PCR. Strain typing was performed using multilocus sequence typing and isolates belonging to the same sequence type (ST) were further typed using multiple-locus variable number tandem repeat analysis (MLVA).

RESULTS

During the 4-month period, rectal swabs were collected from 360 (90.9 %) out of 396 patients who were admitted to the ICU. Among the 360 patients, 314 had stayed in the ICU more than 3 days, of which 213 (73.6 %) had a rectal swab collected within the 3 days prior to discharge from ICU. The prevalence of toxigenic C. difficile colonization was 1.7 % (6 cases) and 4.3 % (10 cases) on admission and discharge, respectively. Only four (1.1 %) out of 360 patients had CDI, corresponding to 10.7 cases per 10,000 ICU days. None of the four cases had toxigenic C. difficile either on admission or at discharge. Toxigenic C. difficile isolates were recovered from all swabs and stool samples positive for tcdB by PCR and belonged to 7 STs (ST2, 3, 6, 37, 54, 103 and 129). None of the isolates belonging to the same ST had identical MLVA patterns. Binary toxin genes were detected in one ST103 isolate that caused colonization.

CONCLUSION

The prevalence of colonization with toxigenic C. difficile among patients on admission to ICU was low in our setting. ICU-acquired toxigenic C. difficile were not linked to those detected on admission. Active screening for toxigenic C. difficile may not be a resource-efficient measure in settings with a low prevalence of colonization.

Optimizing the diagnostic testing of Clostridium difficile infection

INTRODUCTION

Clostridium difficile infection (CDI) is the leading cause of hospital-acquired diarrhea and is associated with a considerable health and cost burden. However, there is still not a clear consensus on the best laboratory diagnosis approach and a wide variation of testing methods and strategies can be encountered.

AREAS COVERED

We aim to review the most practical aspects of CDI diagnosis providing our own view on how to optimize CDI diagnosis. Expert commentary: Laboratory diagnosis in search of C. difficile toxins should be applied to all fecal diarrheic samples reaching the microbiology laboratory in patients > 2 years old, with or without classic risk factors for CDI. Detection of toxins either directly in the fecal sample or in the bacteria isolated in culture confirm CDI in the proper clinical setting. Nuclear Acid Assay techniques (NAAT) allow to speed up the process with epidemiological and therapeutic consequences.

Zoonotic potential of the Clostridium difficile RT078 family in Taiwan

Clostridium difficile is the major cause of nosocomial diarrhea. We have previously demonstrated that in southern Taiwan, severe C. difficile-associated diarrhea (CDAD) cases were due to the C. difficile RT 126 strain infection, indicating the arrival of an epidemic C. difficile clone in southern Taiwan. RT126 has a close genetic relationship with RT078. However, the RT078 family is the predominant strain of C. difficile in animals worldwide, particularly in swine. In this study, we surveyed C. difficile strains isolated from swine at several farms in Taiwan from August 2011 to March 2015. We found that all swine strains, namely RT078 (32.5%, 37 of 114), RT126 (28.9%, 33 of 114) and RT127 (37.7%, 43 of 114), belonged to the toxigenic RT078 family. All strains had high gyrA mutation rate (57.9%, 66/114), which was linked to quinolone resistance. Notably, Rep-PCR revealed that 3 RT078 animal strains had the same fingerprint as human RT078 clinical isolates; their phylogenic relationship was closely related to the whole gene sequences of tcdB, thus suggesting zoonotic potential for C. difficile infection in Taiwan.

Coexisting cytomegalovirus infection in immunocompetent patients with Clostridium difficile colitis

Cytomegalovirus (CMV) colitis usually occurs in immunocompromised patients with human immunodeficiency virus infection, organ transplantation, and malignancy receiving chemotherapy or ulcerative colitis receiving immunosuppressive agents. However, CMV colitis is increasingly recognized in immunocompetent hosts. Notably, CMV colitis coexisting with Clostridium difficile infection (CDI) in apparently healthy individuals has been published in recent years, which could result in high morbidity and mortality. CMV colitis is a rare but possible differential diagnosis in immunocompetent patients with abdominal pain, watery, or especially bloody diarrhea, which could be refractory to standard treatment for CDI. As a characteristic of CDI, however, pseudomembranous colitis may be only caused by CMV infection. Real-time CMV-polymerase chain reaction (PCR) for blood and stool samples may be a useful and noninvasive diagnostic strategy to identify CMV infection when treatment of CDI eventually fails to show significant benefits. Quantitative CMV-PCR in mucosal biopsies may increase the diagnostic yield of traditional histopathology. CMV colitis is potentially life-threatening if severe complications occur, such as sepsis secondary to colitis, massive colorectal bleeding, toxic megacolon, and colonic perforation, so that may necessitate pre-emptive antiviral treatment for those who are positive for CMV-PCR in blood and/or stool samples while pending histological diagnosis.

Effective Sequestration of Clostridium difficile Protein Toxins by Calcium Aluminosilicate

Clostridium difficile is a leading cause of antibiotic-associated diarrhea and the etiologic agent responsible for C. difficile infection. Toxin A (TcdA) and toxin B (TcdB) are nearly indispensable virulence factors for Clostridium difficile pathogenesis. Given the toxin-centric mechanism by which C. difficile pathogenesis occurs, the selective sequestration with neutralization of TcdA and TcdB by nonantibiotic agents represents a novel mode of action to prevent or treat C. difficile-associated disease. In this preclinical study, we used quantitative enzyme immunoassays to determine the extent by which a novel drug, calcium aluminosilicate uniform particle size nonswelling M-1 (CAS UPSN M-1), is capable of sequestering TcdA and TcdB in vitro. The following major findings were derived from the present study. First, we show that CAS UPSN M-1 efficiently sequestered both TcdA and TcdB to undetectable levels. Second, we show that CAS UPSN M-1's affinity for TcdA is greater than its affinity for TcdB. Last, we show that CAS UPSN M-1 exhibited limited binding affinity for nontarget proteins. Taken together, these results suggest that ingestion of calcium aluminosilicate might protect gastrointestinal tissues from antibiotic- or chemotherapy-induced C. difficile infection by neutralizing the cytotoxic and proinflammatory effects of luminal TcdA and TcdB.