Clinical Practice Guidelines for Clostridium difficile Infection in Adults and Children: 2017 Update by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA)

Time-Series Analysis of Health Care-Associated Infections in a New Hospital With All Private Rooms

IMPORTANCE

Health care-associated infections are often caused by multidrug-resistant organisms and substantially factor into hospital costs and avoidable iatrogenic harm. Although it is recommended that new facilities be built with single-room, low-acuity beds, this process is costly and evidence of reductions in health care-associated infections is weak.

OBJECTIVE

To examine whether single-patient rooms are associated with decreased rates of common multidrug-resistant organism transmissions and health care-associated infections.

DESIGN, SETTING, AND PARTICIPANTS

A time-series analysis comparing institution-level rates of new multidrug-resistant organism colonization and health care-associated infections before (January 1, 2013-March 31, 2015) and after (April 1, 2015-March 31, 2018) the move to the hospital with 100% single-patient rooms. In the largest hospital move in Canadian history, inpatients in an older, tertiary care, 417-bed hospital in Montréal, Canada, that consisted of mainly mixed 3- and 4-person ward-type rooms were moved to a new 350-bed facility with all private rooms.

EXPOSURES

A synchronized move of all patients on April 26, 2015, to a new hospital with 100% single-patient rooms equipped with individual toilets and showers and easy access to sinks for hand washing.

MAIN OUTCOMES AND MEASURES

Rates of nosocomial vancomycin-resistant Enterococcus (VRE) and methicillin-resistant Staphylococcus aureus (MRSA) colonization, VRE and MRSA infection, and Clostridioides difficile (formerly known as Clostridium difficile) infection (CDI) per 10 000 patient-days.

RESULTS

Compared with the 27 months before, during the 36 months after the hospital move, an immediate and sustained reduction in nosocomial VRE colonization (from 766 to 209 colonizations; incidence rate ratio [IRR], 0.25; 95% CI, 0.19-0.34) and MRSA colonization (from 129 to 112 colonizations; IRR, 0.57; 95% CI, 0.33-0.96) was noted, as well as VRE infection (from 55 to 14 infections; IRR, 0.30, 95% CI, 0.12-0.75). Rates of CDI (from 236 to 223 infections; IRR, 0.95; 95% CI, 0.51-1.76) and MRSA infection (from 27 to 37 infections; IRR, 0.89, 95% CI, 0.34-2.29) did not decrease.

CONCLUSION AND RELEVANCE

The move to a new hospital with exclusively single-patient rooms appeared to be associated with a sustained decrease in the rates of new MRSA and VRE colonization and VRE infection; however, the move was not associated with a reduction in CDI or MRSA infection. These findings may have important implications for the role of hospital construction in facilitating infection control.

Dual Reporting of Clostridioides difficile PCR and Predicted Toxin Result Based on PCR Cycle Threshold Reduces Treatment of Toxin-Negative Patients without Increases in Adverse Outcomes

Nucleic acid amplification tests are commonly used to diagnose Clostridioides difficile infection (CDI). Two-step testing with a toxin enzyme immunoassay is recommended to discriminate between infection and colonization but requires additional resources. Prior studies showed that PCR cycle threshold (CT ) can predict toxin positivity with high negative predictive value. Starting in October 2016, the predicted toxin result (CT-toxin) based on a validated cutoff was routinely reported at our facility. To evaluate the clinical efficacy of this reporting, all adult patients with positive GeneXpert PCR results from October 2016 through October 2017 underwent a chart review to measure the recurrence of or conversion to a CT-toxin+ result and 30-day all-cause mortality. There were 482 positive PCR tests in 430 unique patients, 282 CT-toxin+ and 200 CT-toxin- Patient characteristics were similar at testing, though CT-toxin+ patients had higher white blood cell (WBC) counts (12.5 × 103 versus 9.3 × 103 cells/μl; P = 0.001). All cases (n = 21) of fulminant CDI had a CT-toxin+ result. Index CT-toxin+ patients were significantly more likely to have a CT-toxin+ result within 90 days than CT-toxin- patients (17.4% [n = 49] versus 8.0% [n = 16], respectively; P = 0.003). Thirty-day all-cause mortality was higher in CT-toxin- patients (11.1% versus 6.8%; P = 0.1), though no deaths in CT-toxin- patients were directly attributable to CDI. Of the 200 CT-toxin- patients, 51.5% (n = 103) were treated for CDI. The rates of conversion to a CT-toxin+ result (8.8% versus 7.2%; P = 0.8) and all-cause mortality (8.8% versus 13.4%; P = 0.3) were similar between treated and untreated CT-toxin- patients, respectively. CT -based toxin prediction may identify patients at higher risk for CDI-related complications and reduce treatment among CT-toxin- patients.

The Impact of the Duration of Antibiotic Therapy in Patients With Community-Onset Pneumonia on Readmission Rates: A Retrospective Cohort Study

BACKGROUND

Recent publications have confirmed that 70% of hospitalized adults with uncomplicated community-acquired pneumonia and health-care-associated pneumonia are prescribed a duration therapy that exceeds current guideline recommendations.

OBJECTIVE

The primary objective is to evaluate the relationship between antibiotic duration and all-cause 30-day readmission rates. Secondary outcomes include pneumonia-specific 30-day readmission rate and identification of risk factors for readmission.

METHODS

Patients aged ≥18 years with a primary diagnosis of pneumonia from January 1, 2016, to December 31, 2016, were included in this single-center, retrospective cohort study. Patients were categorized by antibiotic therapy duration of ≤7 days (n = 139) or >7 days (n = 286), and outcomes were analyzed in both bivariate and multivariate models. A multivariate logistic regression was used to assess the relationship between all-cause 30-day readmission and antibiotic days.

RESULTS

Baseline characteristics were not significantly different between the 2 groups. All-cause 30-day readmission rates were 15.8% and 15.5% for patients who received ≤7 days versus >7 days of antibiotics, respectively (P = .95). Pneumonia-specific 30-day readmission occurred in 3.6% of patients who received antibiotics for ≤7 days compared to 3.5% of patients who received antibiotics for >7 days (P = .95). Multivariate logistic regression showed no statistically significant association between readmission rate and antibiotic duration of >7 days. Statistically significant risk factors for readmission identified by logistic regression include ≥3 hospital admissions within the previous year, a hematocrit <30% at discharge, a history of chronic obstructive pulmonary disorder (COPD), and weight.

CONCLUSION

The use of prolonged antibiotic therapy for the treatment of community-onset pneumonia was not associated with a decrease in all-cause or pneumonia-specific 30-day readmission rates.

Repurposing Geographic Information Systems for Routine Hospital Infection Control

This chapter discusses the potential role of geographic information systems (GIS) for infection control within the hospital system. The chapter provides a brief overview of the role of GIS in public health and reviews current work applying these methods to the hospital setting. Finally, it outlines the potential opportunities and challenges for adapting GIS for use in the hospital setting for infection prevention. A targeted literature review is used to illustrate current use of GIS in the hospital setting. The discussion of complexity was compiled using the nonadoption, abandonment, scale-up, spread, and sustainability (NASSS) framework. Challenges and opportunities were then extracted from this exercise by the authors. There are multiple challenges to implementation of a Hospital GIS for infection prevention, mainly involving the domains of technology, organization, and adaptation. Use of a transdisciplinary approach can address many of these challenges. More research, specifically prospective, reproducible clinical trials, needs to be done to better assess the potential impact and effectiveness of a Hospital GIS in real-world settings. This chapter highlights a powerful but rarely used tool for infection prevention within the hospital. Given the importance of reducing hospital-acquired infection rates, it is vital to identify relevant methods from other fields that could be translated into the field of hospital epidemiology.

Performance Evaluation of the Luminex Aries C. difficile Assay in Comparison to Two Other Molecular Assays within a Multihospital Health Care Center

Clostridioides difficile infection (CDI) remain a serious issue in the United States. Fast and accurate diagnosis of CDI is paramount to achieve immediate infection control initiation, triaging, and isolation, as well as appropriate antibiotic treatment. However, both, over- and underdiagnosis can lead to adverse patient outcomes, such as unnecessary administration of antibiotics or unwanted spread of spores in any hospital setting, respectively.

Clostridioides difficile infection (CDI) remain a serious issue in the United States. Fast and accurate diagnosis of CDI is paramount to achieve immediate infection control initiation, triaging, and isolation, as well as appropriate antibiotic treatment. However, both, over- and underdiagnosis can lead to adverse patient outcomes, such as unnecessary administration of antibiotics or unwanted spread of spores in any hospital setting, respectively. In this prospective study, we evaluated the FDA-cleared Aries C. difficile assay and compared its performance and workflow characteristics to those of the BD Max Cdiff and Xpert C. difficile/Epi assays. Out of 302 samples tested, 55 (18.2%) samples were positive, and 234 (77.5%) samples were negative for C. difficile by all three testing methods. Comparison results showed a positive and negative percent agreement (PPA and NPA, respectively) between the Aries and Xpert assays of 95.2% (59/62) and 99.2% (238/240), respectively. The PPA and NPA between the Aries and BD Max assays were 91.8% (56/61) and 96.6% (230/238), respectively. Invalid result rates were determined to be 2.6% for the BD Max assay, 1.0% for the Aries assay, and 0% for the Xpert assay. Hands-on time (HoT) and total turnaround time (TAT) varied considerably depending on the sample number and instrument throughput. The HoT ranged from 1.2 to 3.5 min per sample, and the TAT was 1 to 2.3 h. Overall, the results demonstrated that the Aries assay is a rapid and sensitive method for the diagnosis of CDI in clinical laboratories.

Ultrasensitive Detection of Clostridioides difficile Toxins in Stool by Use of Single-Molecule Counting Technology: Comparison with Detection of Free Toxin by Cell Culture Cytotoxicity Neutralization Assay

Laboratory tests for Clostridioides difficile infection (CDI) rely on the detection of free toxin or molecular detection of toxin genes. The Singulex Clarity C. diff toxins A/B assay is a rapid, automated, and ultrasensitive assay that detects C. difficile toxins A and B in stool. We compared CDI assays across two prospective multicenter studies to set a cutoff for the Clarity assay and to independently validate the performance compared with that of a cell culture cytotoxicity neutralization assay (CCCNA). The cutoff was set by two sites testing fresh samples from 897 subjects with suspected CDI and then validated at four sites testing fresh samples from 1,005 subjects with suspected CDI. CCCNA testing was performed at a centralized laboratory. Samples with discrepant results between the Clarity assay and CCCNA were retested with CCCNA when the Clarity result agreed with that of at least one comparator method; toxin enzyme immunoassays (EIA), glutamate dehydrogenase (GDH) detection, and PCR were performed on all samples. The cutoff for the Clarity assay was set at 12.0 pg/ml. Compared to results with CCCNA, the Clarity assay initially had 85.2% positive agreement and 92.4% negative agreement. However, when samples with discrepant results between the Clarity assay and CCCNA in the validation study were retested by CCCNA, 13/17 (76.5%) Clarity-negative but CCCNA-positive samples (Clarity⁺/CCCNA^-) became CCCNA^-, and 5/26 (19.2%) Clarity⁺/CCCNA^- samples became CCCNA⁺, resulting in a 96.3% positive agreement and 93.0% negative agreement between Clarity and CCCNA results. The toxin EIA had 59.8% positive agreement with CCCNA. The Clarity assay was the most sensitive free-toxin immunoassay, capable of providing CDI diagnosis in a single-step solution. A different CCCNA result was reported for 42% of retested samples, increasing the positive agreement between Clarity and CCCNA from 85.2% to 96.3% and indicating the challenges of comparing free-toxin results to CCCNA results as a reference standard.

Increased Clinical Specificity with Ultrasensitive Detection of Clostridioides difficile Toxins: Reduction of Overdiagnosis Compared to Nucleic Acid Amplification Tests

Clostridioides difficile infection (CDI) is one of the most common health care-associated infections, resulting in significant morbidity, mortality, and economic burden. Diagnosis of CDI relies on the assessment of clinical presentation and laboratory tests. We evaluated the clinical performance of ultrasensitive single-molecule counting technology for detection of C. difficile toxins A and B. Stool specimens from 298 patients with suspected CDI were tested with the nucleic acid amplification test (NAAT; BD MAX Cdiff assay or Xpert C. difficile assay) and Singulex Clarity C. diff toxins A/B assay. Specimens with discordant results were tested with the cell cytotoxicity neutralization assay (CCNA), and the results were correlated with disease severity and outcome. There were 64 NAAT-positive and 234 NAAT-negative samples. Of the 32 NAAT⁺/Clarity^- and 4 NAAT^-/Clarity⁺ samples, there were 26 CCNA^- and 4 CCNA^- samples, respectively. CDI relapse was more common in NAAT⁺/toxin⁺ patients than in NAAT⁺/toxin^- and NAAT^-/toxin^- patients. The clinical specificity of Clarity and NAAT was 97.4% and 89.0%, respectively, and overdiagnosis was more than three times more common in NAAT⁺/toxin^- than in NAAT⁺/toxin⁺ patients. The Clarity assay was superior to NAATs for the diagnosis of CDI, by reducing overdiagnosis and thereby increasing clinical specificity, and the presence of toxins was associated with negative patient outcomes.

Chemical Space Exploration around Thieno[3,2-d]pyrimidin-4(3H)-one Scaffold Led to a Novel Class of Highly Active Clostridium difficile Inhibitors

Clostridium difficile infection (CDI) is the leading cause of healthcare-associated infection in the United States. Therefore, development of novel treatments for CDI is a high priority. Toward this goal, we began in vitro screening of a structurally diverse in-house library of 67 compounds against two pathogenic C. difficile strains (ATCC BAA 1870 and ATCC 43255), which yielded a hit compound, 2-methyl-8-nitroquinazolin-4(3H)-one (2) with moderate potency (MIC = 312/156 μM). Optimization of 2 gave lead compound 6a (2-methyl-7-nitrothieno[3,2-d]pyrimidin-4(3H)-one) with improved potency (MIC = 19/38 μM), selectivity over normal gut microflora, CC₅₀s > 606 μM against mammalian cell lines, and acceptable stability in simulated gastric and intestinal fluid. Further optimization of 6a at C2-, N3-, C4-, and C7-positions resulted in a library of >50 compounds with MICs ranging from 3 to 800 μM against clinical isolates of C. difficile. Compound 8f (MIC = 3/6 μM) was identified as a promising lead for further optimization.

Fecal microbiota transplant for C. difficile infection: Just say yes

The burden of Clostridium difficile associated diarrhea is a worrying clinical issue worldwide, mainly as regarding the high incidence of recurrences after standard antibiotic therapy and the risk for more severe clinical manifestations. For this reason, new and more effective therapies are needed for the treatment of recurrent episodes. Fecal microbiota transplantation seems to be a valid tool considering the mechanism of action and the growing number of studies that demonstrate its clinical efficacy.

Oncologic Emergencies: The Fever With Too Few Neutrophils

BACKGROUND

Cancer is associated with a variety of complications, including neutropenic fever, which can result in severe morbidity and mortality. This oncologic emergency requires ED management.

OBJECTIVE

This narrative review provides focused updates for emergency clinicians regarding neutropenic fever.

DISCUSSION

Neutropenic fever is defined by fever with oral temperature >38.3°C or temperature >38.0°C for 1 hour with an absolute neutrophil count (ANC) < 1000 cells/microL. Patients who have received chemotherapy within 6 weeks of presentation are at high risk for neutropenia. While most patients with neutropenic fever do not have an identifiable bacterial source of fever, clinicians should treat patients for bacterial infection. Rapid assessment and management are vital to improving outcomes in patients with suspected or confirmed neutropenic fever. History and examination should focus on the most common sites of infection: the gastrointestinal tract, blood, skin, lung, and urinary tract. However, physical examination and laboratory or imaging assessment may not display classic signs of infection. Blood cultures should be obtained, and broad-spectrum antibiotics are recommended. Oncology consultation is an integral component in the care of these patients. Several risk scores can assist in stratifying patients who may be appropriate for discharge home and follow-up.

CONCLUSIONS

Neutropenic fever is an oncologic emergency. Rapid diagnosis and care of patients with neutropenic fever can improve outcomes, along with oncology consultation.

Metronidazole therapy as initial treatment of Clostridium difficile infection in patients with chronic kidney disease in Korea

The risk of metronidazole treatment failure in Clostridium difficile infection (CDI) patients with chronic kidney disease (CKD) or end-stage renal disease in Korea has not been established. We evaluated 481 patients who had been admitted to two secondary hospitals with a diagnosis of, and treatment for, CDI during 2010–2016. CDI patients were divided into three groups according to CKD status: non-CKD (n = 363), CKD (n = 55) and those requiring dialysis (n = 63). Logistic regression analyses were performed to examine the association of CKD status with treatment failure. CDI patients receiving dialysis tended to have increased odds of metronidazole and overall treatment failure compared to non-CKD patients; adjusted odds ratios and 95% confidence intervals were 2.09 (1.03–4.21) and 2.18 (1.11–4.32) for metronidazole and overall treatment failure, respectively. However, CKD patients did not have increased odds of metronidazole or overall treatment failure compared to non-CKD patients, even where severe CDI was more prevalent in CKD patients. The incidence of symptomatic ileus or toxic megacolon did not differ among groups. Our results suggest that initial metronidazole therapy may be considered in CDI patients with non-dialysis CKD, but should not be considered in CDI patients undergoing dialysis.

Clostridium difficile Infection and Colorectal Surgery: Is There Any Risk?

Background and objectives: Clostridium difficile infection (CDI) is an important healthcare-associated infection, with important consequences both from a medical and financial point of view, but its correlation with anastomotic leaks after colorectal surgeries is scarcely reported in the literature. Materials and Methods: We conducted a retrospective study looking for patients who underwent open or laparoscopic surgery for colorectal cancers between January 2012 and December 2017, excluding emergency surgeries for complicated colorectal tumors. We also examined patient history for risk factors for CDI such as age, sex, comorbidities, and clinical findings at admission or during hospital stay as well as tumor characteristics. Results: A total of 360 patients were included in the study, out of which 320 underwent surgeries that included anastomoses. There were 19 cases of anastomotic leaks, out of which 13 patients were diagnosed with CDI, with a statistic significance for association between CDI and anastomotic leakage (p < 0.0001). Most patients who developed both CDI and anastomotic leaks had left-sided resections or a type of rectal resection, while none of the patients with right-sided resections had this association, but with no statistical significance possibly due to the limited number of cases. Conclusions: CDI is a relevant risk factor and should be taken into consideration when trying to prevent anastomotic leaks in patients undergoing gastrointestinal surgery for colon or rectal cancer. Thorough assessment of risk factors at admission should be mandatory in order to adequately prepare the patient and plan an optimal course of treatment. Further studies are needed to confirm our findings and a multidisciplinary approach, with a team which should always include the surgeon, is mandatory when it comes to CDI prevention.

Recent developments in the management of recurrent Clostridioides difficile infection

Clostridioides (formerly Clostridium) difficile is responsible for a substantial burden of nosocomial infection. Recurrent C. difficile infection (rCDI) remains a concern due to its high morbidity, mortality, and cost. Despite the updated 2017 IDSA C. difficile treatment guidelines, there remains a lack of well-studied preventive control measures and treatment modalities for rCDI. There are ongoing efforts to develop novel therapies, such as new antibiotics with a lesser impact on gut microbiota and more targeted therapies, such as bacteriotherapy. This mini review highlights key rCDI management updates, preventive measures and ongoing research on novel treatment strategies including bacteriotherapy.

Framework for rational donor selection in fecal microbiota transplant clinical trials

Early clinical successes are driving enthusiasm for fecal microbiota transplantation (FMT), the transfer of healthy gut bacteria through whole stool, as emerging research is linking the microbiome to many different diseases. However, preliminary trials have yielded mixed results and suggest that heterogeneity in donor stool may play a role in patient response. Thus, clinical trials may fail because an ineffective donor was chosen rather than because FMT is not appropriate for the indication. Here, we describe a conceptual framework to guide rational donor selection to increase the likelihood that FMT clinical trials will succeed. We argue that the mechanism by which the microbiome is hypothesized to be associated with a given indication should inform how healthy donors are selected for FMT trials, categorizing these mechanisms into four disease models and presenting associated donor selection strategies. We next walk through examples based on previously published FMT trials and ongoing investigations to illustrate how donor selection might occur in practice. Finally, we show that typical FMT trials are not powered to discover individual taxa mediating patient responses, suggesting that clinicians should develop targeted hypotheses for retrospective analyses and design their clinical trials accordingly. Moving forward, developing and applying novel clinical trial design methodologies like rational donor selection will be necessary to ensure that FMT successfully translates into clinical impact.

An in-room observation study of hand hygiene and contact precaution compliance for Clostridioides difficile patients

Using an innovative, covert, in-room observer method to evaluate infection control practices for patients with Clostridioides difficile infection, we found no difference between physician and nursing hand hygiene compliance and contact precaution usage. There was also no diurnal variation in hand hygiene practices, but decreased contact precaution usage at night. Conversely, hospital-wide data from overt observations collected over the same time period showed significantly higher hand hygiene compliance among nurses than physicians.

Fecal microbiota transplantation in children: current concepts

PURPOSE OF REVIEW

Administration of fecal material into the gastrointestinal tract, termed fecal microbiota transplantation (FMT), is increasingly recognized as an effective treatment option for recurrent Clostridium difficile infection (RCDI). The impact of FMT on host microbial communities and subsequent disease states has also been explored in recent years for conditions as varied as inflammatory bowel disease especially ulcerative colitis, metabolic diseases, such as diabetes, graft-versus-host disease in hematopoietic stem cell transplant recipients, and autism and autism spectrum disorders. The purpose of this article is to review the evidence for FMT as a treatment option in various pediatric illnesses.

RECENT FINDINGS

The rate of C. difficile infection is rising among children, and is associated with significant morbidity and disease, with recurrence in up to 20% of pediatric patients. Several randomized controlled trials evaluating the utility of FMT in RCDI in comparison to vancomycin have been published and demonstrate high rates of efficacy between 70 and 100%. In addition, the safety of FMT in the treatment of RCDI has been well described in the adult population, with several pediatric case series demonstrating similar rates of tolerability and adverse events. FMT in ulcerative colitis appears promising, especially with multiple infusions administered via the lower gastrointestinal tract. However, there are several limitations, including the lack of uniformity of protocols used, source of FMT, route of administration and the lack of standardization of concomitant therapies. The data on usage of FMT for other indications are preliminary and limited.

SUMMARY

FMT is recognized as an effective treatment option for RCDI and is increasing sought by parents. Although limited, pediatric studies to date on the use of FMT for RCDI demonstrate similar efficacy rates as in the adult population. FMT has been proposed as a treatment option for an increasing number of pediatric conditions, and additional studies are needed to delineate the efficacy of FMT outside of RCDI, as well as its short and long-term impacts on human health.

Effective Dosage of Oral Vancomycin in Treatment for Initial Episode of Clostridioides difficile Infection: A Systematic Review and Meta-Analysis

Background: Oral vancomycin is a first line treatment for an initial episode of Clostridioides difficile infection. However, the comparative efficacy of different dosing regimens is lacking evidence in the current literature. Methods: We searched PubMed, Embase, Cochrane Library, and ClinicalTrials.gov. from inception to May 2019. Only articles published in English are reviewed. This meta-analysis compares the effects of low dose oral vancomycin (<2 g per day) versus high dose vancomycin (2 g per day) for treatment of initial Clostridioides difficile infection. Results: One randomized controlled trial and two retrospective cohort studies are included. A total of 137 patients are identified, 53 of which were treated with low dose oral vancomycin (39%) and 84 with high dose oral vancomycin (61%). There is no significant reduction in recurrence rates with high dose vancomycin compared to low dose vancomycin for treating initial episodes of non-fulminant Clostridioides difficile infection ((odds ratio (OR) 2.058, 95%, confidence interval (CI): 0.653 to 6.489). Conclusions: Based on limited data in the literature, low dose vancomycin is no different than high dose vancomycin for treatment of an initial episode of Clostridioides difficile infection in terms of recurrence rate. Additional large clinical trials comparing the different dosages of vancomycin in initial Clostridioides difficile infection are warranted.

Cross-sectional study of the prevalence, causes and management of hospital-onset diarrhoea

BACKGROUND

The National Health Service in England advises hospitals collect data on hospital-onset diarrhoea (HOD). Contemporaneous data on HOD are lacking.

AIM

To investigate prevalence, aetiology and management of HOD on medical, surgical and elderly-care wards.

METHODS

A cross-sectional study in a volunteer sample of UK hospitals, which collected data on one winter and one summer day in 2016. Patients admitted ≥72 h were screened for HOD (definition: ≥2 episodes of Bristol Stool Type 5-7 the day before the study, with diarrhoea onset >48 h after admission). Data on HOD aetiology and management were collected prospectively.

FINDINGS

Data were collected on 141 wards in 32 hospitals (16 acute, 16 teaching). Point-prevalence of HOD was 4.5% (230/5142 patients; 95% confidence interval (CI) 3.9-5.0%). Teaching hospital HOD prevalence (5.9%, 95% CI 5.1-6.9%) was twice that of acute hospitals (2.8%, 95% CI 2.1-3.5%; odds ratio 2.2, 95% CI 1.7-3.0). At least one potential cause was identified in 222/230 patients (97%): 107 (47%) had a relevant underlying condition, 125 (54%) were taking antimicrobials, and 195 (85%) other medication known to cause diarrhoea. Nine of 75 tested patients were Clostridium difficile toxin positive (4%). Eighty (35%) patients had a documented medical assessment of diarrhoea. Documentation of HOD in medical notes correlated with testing for C. difficile (78% of those tested vs 38% not tested, P<0.001). One-hundred and forty-four (63%) patients were not isolated following diarrhoea onset.

CONCLUSION

HOD is a prevalent symptom affecting thousands of patients across the UK health system each day. Most patients had multiple potential causes of HOD, mainly iatrogenic, but only a third had medical assessment. Most were not tested for C. difficile and were not isolated.

It takes a village: primary care of the pediatric liver transplant recipient

PURPOSE OF REVIEW

Long-term survival is now the rule rather than the exception for infants and children who undergo liver transplantation for end-stage liver disease, metabolic liver conditions and a variety of other indications. Pediatricians and primary care providers play vital roles in the care and management of this patient population. The purpose of this review is to highlight key aspects important to the care of the pediatric liver transplant recipient.

RECENT FINDINGS

Significant advances in immunosuppressive therapies and surgical techniques have contributed to improved graft and patient survival rates, shifting the focus beyond immediate survival to strategies to minimize comorbidities related to long-term immunosuppression during growing years, attend to patient and parent-reported outcomes and enhance quality of life. A multidisciplinary approach allows for monitoring and surveillance of both routine (growth, nutritional rehabilitation, cognitive development, mental and psychosocial health, contraception and daily activities) and transplant-related (adverse effects of immunosuppression, susceptible infections, extra-hepatic systems, transition from childhood to adolescence to adulthood) themes.

SUMMARY

Effective communication between the primary care physician and the transplant team is imperative for optimizing best outcomes. The primary care provider should be aware of the multifacet nature of posttransplant management, which includes medication regimens, common complications and infections.

Role of Cycle Threshold in Clostridioides difficile Polymerase Chain Reaction Testing as a Predictor of Clinical Outcomes in Patients With Inflammatory Bowel Disease

Background

Distinguishing Clostridioides difficile infection from colonization is challenging in patients with Inflammatory Bowel Disease (IBD). Cycle threshold (Ct), the cutoff for PCR positivity, has been investigated in non-IBD patients.

Methods

Patients with positive C. difficile PCR (25 IBD, 51 non-IBD) were identified retrospectively. Fifteen-day outcomes were assessed.

Results

Ct correlated with diarrheal days in non-IBD (P = 0.048), but not IBD patients (P = 0.769). IBD patients had shorter LOS and less severe infection, but more diarrheal days (P &lt; 0.05).

Conclusions

IBD patients had a milder course but Ct results were not significant. Larger studies are needed to clarify utility of Ct in IBD.

Fecal microbiota transplantation for Clostridium difficile infection in Taiwan: Establishment and implementation

Clostridium difficile infection (CDI) remains a major public health issue, and fecal microbiota transplantation (FMT) has become one of the standard therapies for recurrent or refractory CDI. When compared to medical therapies, such as metronidazole or vancomycin, FMT has a high rate of treatment response with acceptable safety and efficiency. Following promulgation of the amendments in September 2018 in Taiwan, FMT has been indicated for recurrent or refractory CDI. The Taiwan Microbiota Consortium contributed to the Taiwan FMT Expert Consensus, which established basic norms and stipulated essential principles, including the indications for transplantation, eligible locations and personnel, donor screening policies, fecal sample handling, and post-FMT follow-up. However, establishing an eligible FMT team in a qualified hospital remains a clinical challenge, and the requirement for facilities and well-screened donors impedes the implementation of FMT. In this review, we aim to provide domestic FMT teams with explicit instructions to facilitate realization and increase the practice of FMT. Based on the Taiwan FMT Expert Consensus and current regulations, we performed a literature review and integrated the experiences of Taiwanese multidisciplinary experts into this article. The content intends to offer clinicians up-to-date evidence and highlight the essential points of FMT.

New concepts in C. difficile management

BACKGROUND

Clostridium difficile infection is transmitted via spores, and the disease is mediated via secreted toxins. It represents a significant healthcare problem, and clinical presentation can range from asymptomatic carriage to life-threatening pseudomembranous colitis.

SOURCES OF DATA

publications in the field, with a focus on recent developments and concepts.

AREAS OF AGREEMENT

infection control measures, antibiotic stewardship and current management of the initial episode of C. difficile infection.

AREAS OF CONTROVERSY

selection and sequence of interventions for the management of recurrent C. difficile infection; management of persistent carriers of toxigenic C. difficile in patients at high risk of subsequent C. difficile infection.

GROWING POINTS

use of faecal microbiota transplantation for recurrent C. difficile infection.

AREAS TIMELY FOR DEVELOPING RESEARCH

role of specific microbiota-mediated interventions and vaccination in the treatment and prevention of C. difficile infection.

Use of Oral Vancomycin for Clostridioides difficile Infection and the Risk of Vancomycin-Resistant Enterococci

Background

Vancomycin is now a preferred treatment for all cases of Clostridioides difficile infection (CDI), regardless of disease severity. Concerns remain that a large-scale shift to oral vancomycin may increase selection pressure for vancomycin-resistant Enterococci (VRE). We evaluated the risk of VRE following oral vancomycin or metronidazole treatment among patients with CDI.

Methods

We conducted a retrospective cohort study of patients with CDI in the US Department of Veterans Affairs health system between 1 January 2006 and 31 December 2016. Patients were included if they were treated with metronidazole or oral vancomycin and had no history of VRE in the previous year. Missing data were handled by multiple imputation of 50 datasets. Patients treated with oral vancomycin were compared to those treated with metronidazole after balancing on patient characteristics using propensity score matching in each imputed dataset. Patients were followed for VRE isolated from a clinical culture within 3 months.

Results

Patients treated with oral vancomycin were no more likely to develop VRE within 3 months than metronidazole-treated patients (adjusted relative risk, 0.96; 95% confidence interval [CI], .77 to 1.20), equating to an absolute risk difference of −0.11% (95% CI, −.68% to .47%). Similar results were observed at 6 months.

Conclusions

Our results suggest that oral vancomycin and metronidazole are equally likely to impact patients’ risk of VRE. In the setting of stable CDI incidence, replacement of metronidazole with oral vancomycin is unlikely to be a significant driver of increased risk of VRE at the patient level.

In this multicenter, retrospective cohort study of patients with Clostridioides difficile infection, the use of oral vancomycin did not increase the risk of vancomycin-resistant Enterococci infection at 3 or 6 months compared to metronidazole.

Management of Clostridioides (formerly Clostridium) difficile infection (CDI) in solid organ transplant recipients: Guidelines from the American Society of Transplantation Community of Practice

These updated guidelines from the American Society of Transplantation Infectious Diseases Community of Practice address the prevention and management of Clostridium difficile infection in solid organ transplant (SOT) recipients. Clostridioides (formerly Clostridium) difficile infection (CDI) is among the most common hospital acquired infections. In SOT recipients, the incidence of CDI varies by type and number or organs transplanted. While a meta-analysis of published literature found the prevalence of postoperative CDI in the general surgical population to be approximately 0.51%, the prevalence of CDI that is seen in the solid organ transplant population ranges from a low of 3.2% in the pancreatic transplant population to 12.7% in those receiving multiple organ transplants. There are no randomized, controlled trials evaluating the management of CDI in the SOT population. Herein is a review and summary of the currently available literature that has been synthesized into updated treatment guidelines for the management of CDI in the SOT population.

Improving our mechanistic understanding of the indirect effects of CMV infection in transplant recipients

Cytomegalovirus (CMV) is an immunomodulatory virus that indirectly increases the risk for bacterial, fungal, and viral infections. However, the pathogenesis of this phenomenon is poorly understood. We determined whether inflammatory responses to different Toll-like receptor (TLR) ligands are blunted during CMV infection in solid-organ transplant (SOT) patients. Peripheral blood mononuclear cells from 38 SOT patients with and without CMV were incubated in the presence of various viral, fungal, and bacterial TLR ligands. Cytokines were measured in the supernatant by multiplex enzyme-linked immunosorbent assay. Patients had blunted cytokine responses to bacterial, fungal, and viral ligands during CMV infection when compared to the absence of CMV infection. This was independent of viral load, clinical presentation of CMV infection or immunosuppression, supporting the clinical observation in SOT recipients that CMV infection increases susceptibility to bacterial, fungal, and other viral infections. Moreover, in the absence of CMV infection, patients with subsequent CMV infection had lower cytokines in response to TLR ligands compared to those without subsequent CMV infection, suggesting that inherent differences in patients not directly related to CMV also contribute to this increased susceptibility. In summary, these data provide novel ex vivo evidence to support indirect effects of CMV.

Diagnosis and management of diarrhea in solid-organ transplant recipients: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of diarrhea in the pre- and post-transplant period. Diarrhea in an organ transplant recipient may result in significant morbidity including dehydration, increased toxicity of medications, and rejection. Transplant recipients are affected by a wide range of etiologies of diarrhea with the most common causes being Clostridioides (formerly Clostridium) difficile infection, cytomegalovirus, and norovirus. Other bacterial, viral, and parasitic causes can result in diarrhea but are far less common. Further, noninfectious causes including medication toxicity, inflammatory bowel disease, post-transplant lymphoproliferative disease, and malignancy can also result in diarrhea in the transplant population. Management of diarrhea in this population is directed at the cause of the diarrhea, instituting therapy where appropriate and maintaining proper hydration. Identification of the cause to the diarrhea needs to be timely and focused.

The gut microbiota in transplant patients

Solid organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients are at increased risk for developing infections due to underlying immunosuppression. Antibiotic use, and in HSCT recipients, the use of preparative regimens prior to transplantation can deplete gut commensal bacteria, resulting in intestinal dysbiosis. Emerging evidence in transplant patients, particularly HSCT, suggest that disturbances in gut microbiota populations are associated with a number of adverse outcomes. Here, we review the outcomes of HSCT and SOT recipients with gut microbiota imbalance or dysbiosis, explore the nascent field of gut microbiome therapeutic approaches including fecal microbiota transplantation and the use of precision probiotics in HSCT and SOT recipients.

Fecal microbiota transplantation (FMT) for C. difficile infection, just say 'No'

Despite lack of regulatory approval, fecal microbiota transplantation (FMT) is widely performed to manage C. difficile infection (CDI), particularly recurrent CDI. Herein, we critically review the available randomized controlled trials of FMT and address the following questions: Is FMT better than drug management of recurrent CDI?; Is FMT treatment per se or adjunctive treatment to antibiotics for CDI?; and, Is FMT safe? Finally, we elaborate non-FMT options for the management of recurrent CDI. Although promising, FMT should be reserved for patients who have failed appropriate antibiotic management of recurrent CDI.

Clostridioides difficile: diagnosis and treatments

Clostridioides difficile (formerly Clostridium) is a major cause of healthcare associated diarrhea, and is increasingly present in the community. Historically, C difficile infection was considered easy to diagnose and treat. Over the past two decades, however, diagnostic techniques have changed in line with a greater understanding of the physiopathology of C difficile infection and the use of new therapeutic molecules. The evolution of diagnosis showed there was an important under- and misdiagnosis of C difficile infection, emphasizing the importance of algorithms recommended by European and North American infectious diseases societies to obtain a reliable diagnosis. Previously, metronidazole was considered the reference drug to treat C difficile infection, but more recently vancomycin and other newer drugs are shown to have higher cure rates. Recurrence of infection represents a key parameter in the evaluation of new drugs, and the challenge is to target the right population with the adapted therapeutic molecule. In multiple recurrences, fecal microbiota transplantation is recommended. New approaches, including antibodies, vaccines, and new molecules are already available or in the pipeline, but more data are needed to support the inclusion of these in practice guidelines. This review aims to provide a baseline for clinicians to understand and stratify their choice in the diagnosis and treatment of C difficile infection based on the most recent data available.

Non-antibiotic therapy for Clostridioides difficile infection: a review

Clostridioides difficile infection (CDI) is a common infectious disease that is mainly caused by antibiotics. Antibiotic therapy is still the dominant treatment for CDI, although it is accompanied by side effects. Probiotics, fecal microbiota transplantation (FMT), engineered microorganisms, bacteriophages, diet, natural active substances, nanoparticles and compounds are examples of emerging non-antibiotic therapies that have received a great amount of attention. In this review, we collected data about different non-antibiotic therapies for CDI and provided a comprehensive analysis and detailed comparison of these therapies. The mechanism of action, therapeutic efficacy, and the strengths and weaknesses of these non-antibiotic therapies have been investigated to provide a basis for the reasonable alternative of non-antibiotic therapies for CDI. In summary, probiotics and FMT are currently the best choice for non-antibiotic therapy for CDI.

Prospective Review of Clostridioides difficile Testing Indications to Inform Local Laboratory Stewardship Initiatives

We conducted a prospective chart review to determine the prevalence of and reasons for inappropriate Clostridioides difficile test-ordering at a tertiary care hospital. Inappropriate orders accounted for 54% of all tests. The two primary aetiologies of inappropriate test-ordering were an alternative reason for diarrhoea (34%) and an asymptomatic patient (20%). These results highlight the need to focus diagnostic stewardship of C. difficile testing on pre-analytical factors.

Risk factors for Clostridioides (Clostridium) difficile infection following solid organ transplantation in children

BACKGROUND

Clostridioides (Clostridium) difficile infection (CDI) in pediatric solid organ transplant (SOT) recipients is a growing problem, though CDI risk factors in this population are poorly understood. Our objective was to characterize CDI risk factors in pediatric SOT recipients.

METHODS

This retrospective case-control study, performed at a single freestanding academic children's hospital, included all SOT recipients age 1-22 years who were tested for C. difficile by toxin B gene PCR between August 2009 and August 2017. CDI risk factors were assessed by comparing PCR-positive and PCR-negative cases by generalized linear mixed models.

RESULTS

Between August 2009 and August 2017, 409 SOTs were performed of which 138 (33.7%), 134 (32.8%), 131 (32.0%), and 6 (1.5%) were kidney, liver, heart, and small intestine transplants, respectively. Of 205 SOT recipients were tested for CDI, with 723 C. difficile PCR tests performed among these patients. 68/205 (33%) patients developed CDI at least once during the study period. Median (interquartile range) time to diagnosis of first CDI following SOT was 8.9 (1.2, 19.6) months. CDI was independently associated with calcineurin inhibitor use at time of C. difficile testing (odds ratio [OR] 2.38, 95% confidence interval [CI] 1.08, 5.24, P = 0.03) and systemic antibiotic exposure within 30 days of C. difficile testing (OR 1.74, 95% CI 1.08, 2.79, P = 0.02).

CONCLUSIONS

CDI is a common, relatively late post-transplant complication and independently associated with calcineurin inhibitor and systemic antibiotic exposure. The potential impact of specific immunosuppressive drug and antibiotic selection on CDI risk reduction requires further investigation.

Influence of Diagnostic Method on Outcomes in Phase 3 Clinical Trials of Bezlotoxumab for the Prevention of Recurrent Clostridioides difficile Infection: A Post Hoc Analysis of MODIFY I/II

Background

The optimum diagnostic test method for Clostridioides difficile infection (CDI) remains controversial due to variation in accuracy in identifying true CDI. This post hoc analysis examined the impact of CDI diagnostic testing methodology on efficacy outcomes in phase 3 MODIFY I/II trials.

Methods

In MODIFY I/II (NCT01241552/NCT01513239), participants received bezlotoxumab (10 mg/kg) or placebo during anti-CDI treatment for primary/recurrent CDI (rCDI). Using MODIFY I/II pooled data, initial clinical cure (ICC) and rCDI were assessed in participants diagnosed at baseline using direct detection methods (enzyme immunoassay [EIA]/cell cytotoxicity assay [CCA]) or indirect methods to determine toxin-producing ability (toxin gene polymerase chain reaction [tgPCR]/toxigenic culture).

Results

Of 1554 participants who received bezlotoxumab or placebo in MODIFY I/II, 781 (50.3%) and 773 (49.7%) were diagnosed by tgPCR/toxigenic culture and toxin EIA/CCA, respectively. Participants diagnosed by toxin EIA/CCA were more likely to be inpatients, older, and have severe CDI. In bezlotoxumab recipients, ICC rates were slightly higher in the toxin EIA/CCA subgroup (81.7%) vs tgPCR/toxigenic culture (78.4%). Bezlotoxumab significantly reduced the rCDI rate vs placebo in both subgroups; however, the magnitude of reduction was substantially larger in participants diagnosed by toxin EIA/CCA (relative difference, –46.6%) vs tgPCR/toxigenic culture (–29.1%). In bezlotoxumab recipients, the rCDI rate was lower in the toxin EIA/CCA subgroup (17.6%) vs tgPCR/toxigenic culture (23.6%; absolute difference, –6.0%; 95% confidence interval, –12.4 to 0.3; relative difference, –25.4%).

Conclusions

Diagnostic tests that detect fecal C. difficile toxins are of fundamental importance to accurately diagnosing CDI, including in clinical trial design, ensuring that therapeutic efficacy is not underestimated.

Probiotic use as prophylaxis for Clostridium difficile-associated diarrhea in a community hospital

This study was a retrospective chart review from January 1, 2015 through June 30, 2017, comparing the incidence of Clostridium difficile-associated diarrhea (CDAD) in patients taking select broad spectrum antibiotics with probiotics versus without probiotics. The purpose was to determine if probiotic use was associated with a reduction in the incidence of CDAD. A total of 5,574 hospital encounters were reviewed, showing a 0.96% incidence of CDAD in patients receiving a probiotic compared to a 2.19% incidence of CDAD in patients with no probiotic (risk ratio = 0.442; P = .00743). These findings show probiotic use was associated with a statistically significant lower incidence of positive C. difficile test results compared to no probiotic use.

Modified glove use for contact precautions: Health care workers' perceptions and acceptance

BACKGROUND

Patients colonized or infected with methicillin-resistant Staphylococcus aureus and or vancomycin-resistant Enterococcus are placed under contact precautions. Contact precautions require patients to be placed in single rooms and their health care workers (HCWs) to wear gowns, aprons and gloves on entry and doffing on exit. Glove use is widely accepted to be associated with poor hand hygiene compliance. We trailed the removal of gloves for contact precautions for contacts not expected to involve body fluids to improve hand hygiene between multiple contacts of the patient and patient zone.

METHODS

We have conducted a 5 phase study of the removal of gloves for contacts without body fluids in 250 HCWs using pretrial focus groups (N = 12), hand microbiology (N = 40) (reported elsewhere), development of a modified contact precautions poster, trial of modified poster (n = 100), posttrial focus group discussion (n = 22), and a survey of HCWs postrollout in additional locations (n = 76).

RESULTS

Pretrial focus groups identified 4 themes, and the leading theme identified as the facilitator for glove use as self-protection. HCWs viewed current contact precaution guidelines as preventing them from making their own judgement regarding the need for gloving for patient contacts, leading continuous glove use without changing gloves between multiple contacts. Participants believed that the trial empowered them to make their own clinical judgment for gloves and to consciously use hand hygiene between dry (no body fluid) contacts. Four themes were discussed during the posttrial focus groups and although self-protection remained the central theme, hand hygiene replaced glove use. Participants spoke of an appreciation of and increased trust in hand hygiene during nonglove use for dry contacts. The survey responses from additional sites were mostly positive for the safety of nonglove use for dry contacts, it improved hand hygiene and that the adoption of the modified guidelines was empowering.

CONCLUSIONS

The trial of nonglove use for expected dry contact, while caring for patients under contact precautions for methicillin-resistant S aureus and or vancomycin-resistant Enterococcus, was successful in refocusing HCWs reliance on hand hygiene for self-protection. Mandatory glove use for contact precautions was believed to contribute to their failure to change gloves between procedures on the same patient and patient zone, with HCWs now recognizing multiple contacts with the same gloves as a risk for contamination.

High 30-day readmission rates associated with Clostridiumdifficile infection

BACKGROUND

Clostridium difficile infection (CDI) is a leading cause of community-onset and healthcare-associated infection, with high recurrence rates, and associated high morbidity and mortality. We report national rates, leading causes, and predictors of hospital readmission for CDI.

METHODS

Retrospective study of data from the 2013 Nationwide Readmissions Database of patients with a primary diagnosis of CDI and re-hospitalization within 30-days. A multivariate regression model was used to identify predictors of readmission.

RESULTS

Of 38,409 patients admitted with a primary diagnosis of CDI, 21% were readmitted within 30-days, and 27% of those patients were readmitted with a primary diagnosis of CDI. Infections accounted for 47% of all readmissions. Female sex, anemia/coagulation defects, renal failure/electrolyte abnormalities and discharge to home (versus facility) were 12%, 13%, 15%, 36%, respectively, more likely to be readmitted with CDI.

CONCLUSIONS

We found that 1-in-5 patients hospitalized with CDI were readmitted to the hospital within 30-days. Infection comprised nearly half of these readmissions, with CDI being the most common etiology. Predictors of readmission with CDI include female sex, history of renal failure/electrolyte imbalances, anemia/coagulation defects, and being discharged home. CDI is associated with a high readmission risk, with evidence of several predictive risks for readmission.

Strategies for the eradication of extended-spectrum beta-lactamase or carbapenemase-producing Enterobacteriaceae intestinal carriage

Introduction: Among the multidrug resistant pathogens, extended-spectrum beta-lactamase (ESBL-E) or carbapenemase-producing Enterobacteriaceae (CPE) are currently considered the main threat due to the scarcity of therapeutic options and their rapid spread around the globe. In addition to developing new antibiotics and stopping transmission, recent research has focused on 'decolonization' strategies to eradicate the carriage of ESBL-E/CPE before infection occurs. Areas covered: In this narrative review, we aim to describe the current evidence of decolonization strategies for ESBL-E or CPE intestinal carriage. We first define decolonization and highlight the issues related to the lack of standardized definitions, then we summarize the available data on the natural history of colonization. Finally, we review the strategies assessed over the past 10 years for ESBL and CPE decolonization: oral antibiotics, probiotics and more recently fecal microbiota transplantation. We conclude by presenting the risks and uncertainties associated with these strategies. Expert opinion: The evidence available today is too low to recommend decolonization strategies for ESBL-E or CPE in routine clinical practice. The potential increase of resistance and the impact of microbiome manipulation should not be underestimated. Some of these decolonization strategies may nevertheless be effective, at least in temporarily suppressing colonization, which could be useful for specific populations such as high-risk patients. Effectiveness and long-term effects must be properly assessed through well-designed randomized controlled trials.

Gut Microbiota Modulation for Multidrug-Resistant Organism Decolonization: Present and Future Perspectives

The emergence of antimicrobial resistance (AMR) is of great concern to global public health. Treatment of multi-drug resistant (MDR) infections is a major clinical challenge: the increase in antibiotic resistance leads to a greater risk of therapeutic failure, relapses, longer hospitalizations, and worse clinical outcomes. Currently, there are no validated treatments for many MDR or pandrug-resistant (PDR) infections, and preventing the spread of these pathogens through hospital infection control procedures and antimicrobial stewardship programs is often the only tool available to healthcare providers. Therefore, new solutions to control the colonization of MDR pathogens are urgently needed. In this narrative review, we discuss current knowledge of microbiota-mediated mechanisms of AMR and strategies for MDR colonization control. We focus particularly on fecal microbiota transplantation for MDR intestinal decolonization and report updated literature on its current clinical use.

Small-Molecule Inhibition of the C. difficile FAS-II Enzyme, FabK, Results in Selective Activity

Clostridioides difficile infection (CDI) is a leading cause of significant morbidity, mortality, and healthcare-related costs in the United States. After standard therapy, recurrence rates remain high, and multiple recurrences are not uncommon. Causes include treatments employing broad-spectrum agents that disrupt the normal host microbiota, as well as treatment-resistant spore formation by C. difficile. Thus, novel druggable anti-C. difficile targets that promote narrow-spectrum eradication and inhibition of sporulation are desired. As a critical rate-limiting step within the FAS-II bacterial fatty acid synthesis pathway, which supplies precursory component phospholipids found in bacterial cytoplasmic and spore-mediated membranes, enoyl-acyl carrier protein (ACP) reductase II (FabK) represents such a target. FabK is essential in C. difficile (CdFabK) and is structurally and mechanistically distinct from other isozymes found in gut microbiota species, making CdFabK an attractive narrow-spectrum target. We report here the kinetic evaluation of CdFabK, the biochemical activity of a series of phenylimidazole analogues, and microbiological data suggesting these compounds' selective antibacterial activity against C. difficile versus several other prominent gut organisms. The compounds display promising, selective, low micromolar CdFabK inhibitory activity without significantly affecting the growth of other gut organisms, and the series prototype (1b) is shown to be competitive for the CdFabK cofactor and uncompetitive for the substrate. A series analogue (1g) shows maintained inhibitory activity while also possessing increased solubility. These findings represent the basis for future drug discovery efforts by characterizing the CdFabK enzyme while demonstrating its druggability and potential role as a narrow-spectrum antidifficile target.

Increasing antibiotic resistance in Clostridioides difficile: A systematic review and meta-analysis

BACKGROUND

Decreases in clinical response of Clostridioides difficile to antibiotics used for its treatment have raised concerns regarding antibiotic resistance. We conducted a systematic review and meta-analysis to study the resistance rates of C. difficile to various antibiotics over time.

METHODS

We systematically searched MEDLINE, Embase, and Web of Science from inception through 03/31/2017 for observational studies assessing antibiotic resistance rates in C. difficile. Weighted summary estimates were calculated using inverse variance heterogeneity models [MetaXL software (v. 5.3)]. A priori subgroup analyses were done (by study year, continent, susceptibility testing method, origin of isolates); ribotype 027 strains were analyzed separately.

RESULTS

From 1982 to 2017, 60 studies (8336 isolates) were analyzed. Fifty-three studies reported vancomycin resistance; weighted pooled resistance (WPR), 2.1% (95% CI, 0%-5.1%; I² = 95%). Fifty-five studies reported metronidazole resistance; WPR, 1.9% (95% CI, 0.5%-3.6%; I² = 89%). Compared to the period before 2012, vancomycin resistance increased by 3.6% (95% CI, 2.9%-4.2%; P < 0.001) after 2012, and metronidazole resistance decreased by 0.8% (95% CI, 0.1%-1.5%; P = 0.02). No isolates were resistant to fidaxomicin.

CONCLUSION

Resistance of C. difficile to vancomycin is increasing, with a smaller, declining resistance to metronidazole; there is significant heterogeneity between studies. Ongoing monitoring of resistance to commonly used antibiotics is required.

Outcomes of a Multidisciplinary Clinic in Evaluating Recurrent Clostridioides difficile Infection Patients for Fecal Microbiota Transplant: A Retrospective Cohort Analysis

Fecal microbiota transplantation (FMT) has been shown to be an effective treatment for recurrent Clostridioides difficile infections (rCDIs). We assessed the benefits of a multidisciplinary C. difficile clinic for screening FMT eligibility in patients with rCDI. Patients seen at the University of Virginia Complicated C. difficile Clinic (CCDC) underwent comprehensive evaluation for possible FMT. Patients were eligible for FMT if there was history of greater than two episodes of rCDI. Patients were evaluated for the outcome after evaluation in the clinic. A total of 113 patients were evaluated: 77 were eligible for FMT, of which 25 patients did not undergo FMT. The rate of recurrence at three months and all-cause mortality were 4.5% and 7% for patients who received FMT and 16.7% and 12.5% for eligible patients who did not receive FMT. There were 36 patients who were not eligible for FMT, with two or fewer recurrences and a recurrence rate of 8.8% and all-cause mortality of 6%. One in three patients screened for FMT had a nutritional deficiency diagnosed, with zinc deficiency being most common (20%). Additional diagnoses, including inflammatory bowel disease, were made during the evaluation. FMT is a highly effective treatment for rCDI, most notably in patients with multiple recurrences. A systematic approach for evaluating patients with rCDI helps identify patients who benefit most from FMT and those who have other conditions.

Clostridium difficile colitis: CT findings and differential diagnosis

Clostridium difficile infection (CDI) is a severe and potentially deadly infectious colitis whose incidence is dramatically increasing in the last decades, with more virulent strains. CDI should be suspected in case of unexplained diarrhea and abdominal pain in patients with a recent history of antibiotic use and healthcare exposures; diagnosis is based on a combination of clinical and laboratory findings with demonstration of C. difficile toxins by stool test. The advantages of contrast-enhanced computed tomography (CECT) are the noninvasiveness and the ability to evaluate both the colonic wall and the adjacent soft tissues. Considerable overlap exists between the CECT findings of CDI and those of colitis of other origins, such as typhlitis, ischemic colitis, graft-versus-host disease, radiation colitis and inflammatory bowel diseases; however, some features may help distinguish between these conditions. This paper provides a comprehensive overview of the imaging features of Clostridium difficile colitis and its mimics, with a view to assist the radiologist in reaching the correct diagnosis.