Clostridium difficile: Diagnosis and the Consequence of Over Diagnosis

Positive impact of a diagnostic stewardship intervention on syndromic panel ordering practices and inappropriate C. difficile treatment

OBJECTIVE

Multiplex polymerase chain reaction (PCR) panels for stool testing may be used to diagnose Clostridioides difficile, which can circumvent more appropriate targeted C. difficile testing, resulting in treatment of incidentally detected colonization. We sought to reduce C. difficile diagnosis via a gastrointestinal pathogen panel (GIPP).

DESIGN

Quasi-experimental, pre/post, retrospective cohort study from January 1, 2022, to January 31, 2024.

SETTING

Mayo Clinic Arizona-a single academic medical center and associated clinics.

PATIENTS

Adult patients receiving C. difficile testing and/or treatment.

METHODS

Preferred C. difficile testing consisted of glutamate dehydrogenase and toxin antigen immunoassay, followed by toxin gene testing for discrepant results. The GIPP contained 22 targets during the baseline period with C. difficile removed during the postintervention period. Surveys were provided to provider and nursing groups, separately, to identify C. difficile ordering practices and knowledge gaps.

RESULTS

At baseline, from January 1, 2022, to January 31, 2023, 2,772 GIPPs were completed for 2,307 unique patients (∼7 per day), primarily for outpatients (1,805 of 2,772, 65%). The most common positive target was C. difficile (517 of 1,018, 51%), which resulted in treatment for C. difficile infection in 94.9% (337 of 355) of cases. Following GIPP C. difficile target removal, GIPP orders decreased from 3.23 to 2.7 per 1,000 patient visits (P < .001). Prescribing of C. difficile treatments decreased in the postintervention period in inpatient and outpatient settings. There were no cases of delayed C. difficile diagnosis during the postintervention period.

CONCLUSIONS

Removing C. difficile from the GIPP resulted in effective diagnostic and antimicrobial stewardship without resulting in delayed diagnoses.

Bioengineered Probiotics for Clostridioides difficile Infection: An Overview of the Challenges and Potential for This New Treatment Approach

The rapid increase in microbial antibiotic resistance in Clostridioides difficile (C. difficile) strains and the formation of hypervirulent strains have been associated with a global increase in the incidence of C. difficile infection (CDI) and subsequently, an increase in the rate of recurrence. These consequences have led to an urgent need to develop new and promising alternative strategies to control this pathogen. Engineered probiotics are exciting new bacterial strains produced by editing the genome of the original probiotics. Recently, engineered probiotics have been used to develop delivery vehicles for vaccines, diagnostics, and therapeutics. Recent studies have demonstrated engineered probiotics may potentially be an effective approach to control or treat CDI. This review provides a brief overview of the considerations for engineered probiotics for medicinal use, with a focus on recent preclinical research using engineered probiotics to prevent or treat CDI. We also address the challenges faced in the production of engineered strains and how they may be overcome in the application of these agents to meet patient needs in the future.

Evaluation of preoperative antibiotic prophylaxis in clean-wound general surgery procedures: a propensity score-matched cohort study at a regional hospital

BACKGROUND

The administration of antibiotic prophylaxis for clean-wound surgeries is controversial among surgeons, despite guidelines suggesting its use. This study aimed to evaluate its effectiveness in preventing surgical site infections (SSIs) in clean-wound surgeries within a regional setting with varied practices regarding prophylaxis.

MATERIALS AND METHODS

This retrospective cohort study included four types of common general surgeries performed from March 2021 to February 2023 at a tertiary regional hospital in Thailand. The surgeries included skin/subcutaneous excision, thyroidectomy, inguinal hernia repair, and breast surgeries, all of which required regional or general anesthesia. Antibiotic prophylaxis was administered at the discretion of the attending surgeons. SSI diagnosis followed standard diagnostic criteria, involving reviewing medical records and the records of the infection control unit. Infection risk factors were examined. The primary outcome comparison used inverse probability treatment weighting of propensity scores, with covariate balance evaluated.

RESULTS

Of the 501 surgeries identified, 84 were excluded, leaving 417 eligible for analysis. Among these patients, 233 received prophylactic antibiotics, for an SSI rate of 1.3%, while 184 did not receive antibiotics, for an SSI rate of 2.2%. A comparative analysis using propensity score weighting revealed no statistically significant difference in the incidence of SSI between the groups (risk ratio [95% confidence interval]: 0.54 (0.11, 2.50), p = 0.427).

CONCLUSION

In this practical setting, with the given study size, antibiotic prophylaxis in common general surgeries involving clean wounds did not significantly prevent SSIs. Routine use recommendations should be re-evaluated.

TRIAL REGISTRATION

Not applicable as this study is a retrospective cohort study and not a clinical trial.

Diagnostic and therapeutic management of Clostridioides difficile infection

A review of the diagnostic and therapeutic management algorithm of the pathogen Clostridioides difficile for daily practice is presented. Its diagnosis, in any unformed stool sample sent to the laboratory, is based on a two-step algorithm, with demonstration of the pathogen by means of its enzyme glutamate dehydrogenase by immunoassay and subsequent PCR (polymerase chain reaction) of its toxin. The mainstay of step therapy, reserved for symptomatic patients, is fidaxomicin, over vancomycin. Metronidazole is not an adequate treatment. Emerging therapies, such as faecal microbiota transplantation or the antibody bezlotoxumab, are gaining importance in patients with risk factors or relapses. Surgery is indicated in patients with worse prognosis and complications. Prevention is essential, based on vigilance and contact precautions, in addition to the elimination of spores from the environment.

Therapeutics involved in managing initial and recurrent Clostridium difficile infection: An updated literature review

Clostridium difficile infection (CDI) has been increasing due to the effect of recurrent hospitalizations. The use of antibiotics has been shown to alter the gut microbiome and lead to CDIs. The treatment is limited to three major antibiotics; however, the incidence of recurrent CDIs has been increasing and drug resistance is a major concern. This aspect is a growing concern in modern medicine especially in the elderly population, critical care patients, and immunocompromised individuals who are at high risk of developing CDIs. Clostridium difficile can lead to various complications including septic shock and fulminant colitis that could prove to be lethal in these patients. Newer modalities of treatment have been developed including bezlotoxumab, a monoclonal antibody and fecal microbiota transplant. There have been studies showing asymptomatic carriers and drug resistance posing a major threat to the healthcare system. Newer treatment options are being studied to treat and prevent CDIs. This review will provide an insight into the current treatment modalities, prevention and newer modalities of treatment and challenges faced in the treatment of CDIs.

Virulence factors, antibiotic susceptibility and sequence type distribution of hospital-associated Clostridioides difficile isolates in Israel, 2020-2022

Biofilm formation and toxin production are some of the virulence factors of Clostridioides difficile (C. difficile), which causes hospital-acquired C. difficile infection (HA-CDI). This work investigated the prevalence and distribution of different strains recovered from HA-CDI patients hospitalized in 4 medical centres across Israel, and characterized strains' virulence factors and antibiotic susceptibility. One-hundred and eighty-eight faecal samples were collected. C. difficile 's toxins were detected by the CerTest Clostridium difficile GDH + Toxin A + B combo card test kit. Toxin loci PaLoc and PaCdt were detected by whole-genome sequencing (WGS). Multi-locus sequence typing (MLST) was performed to classify strains. Biofilm production was assessed by crystal violet. Antibiotic susceptibility was determined using Etest. Fidaxomicin susceptibility was tested via agar dilution. Sequence type (ST) 42 was the most (13.8%) common strain. All strains harboured the 2 toxins genes; 6.9% had the binary toxin. Most isolates were susceptible to metronidazole (98.9%) and vancomycin (99.5%). Eleven (5.85%) isolates were fidaxomicin-resistant. Biofilm production capacity was associated with ST (p < 0.001). In conclusion, a broad variety of C. difficile strains circulate in Israel's medical centres. Further studies are needed to explore the differences and their contribution to HA-CDI epidemiology.

Emerging Diagnostics in Clostridioides difficile Infection

Clostridioides difficile detection in community settings is time-intensive, resulting in delays in diagnosing and quarantining infected individuals. However, with the advent of semi-automated devices and improved algorithms in recent decades, the ability to discern CDI infection from asymptomatic carriage has significantly improved. This, in turn, has led to efficiently regulated monitoring systems, further reducing endemic risk, with recent concerns regarding a possible surge in hospital-acquired Clostridioides difficile infections post-COVID failing to materialize. This review highlights established and emerging technologies used to detect community-acquired Clostridioides difficile in research and clinical settings.

More than a new name: Updates in the management of Clostridioides difficile infection

ABSTRACT

Infections from Clostridioides difficile (often called C. diff) have long presented challenges for both patients and clinicians. Traditionally, C. diff has been considered a nosocomial infection, but in recent years, a noticeable spike in community-acquired cases has occurred. C. diff infection (CDI) testing is often complicated, as various testing options with differing sensitivity and specificity for active infection are available. Also, recent guideline changes have altered the recommended treatment of infection. This article discusses recent changes to both the diagnosis and management of CDI and how they can be applied to everyday NP practice.

Impact of an electronic smart order-set for diagnostic stewardship of Clostridiodes difficile infection (CDI) in a community healthcare system in South Florida

BACKGROUND

Inappropriate testing for Clostridiodes difficile infection (CDI) increases health care onset cases and contributes to overdiagnosis and overtreatment of patients in a community health care system.

METHODS

An electronic smart order set for the testing of CDI was created and implemented to improve the appropriateness of testing. A retrospective review of patients who were tested for CDI, pre and post, was conducted to determine if inappropriate stool testing for CDI decreased post-implementation of the order set.

RESULTS

224 patients were tested for CDI during the study period with the post-implementation period having a higher proportion of patients who met appropriate testing criteria defined by presence of diarrhea (80.5% vs 61.3%; P = .002). The rate of inappropriate CDI stool testing decreased from 31.1% to 11.0% after implementation (P < .001). A higher proportion of CDI patients were readmitted within 30 days of discharge (54.2% vs 33.0%; P = 0.001) during the post-implementation period.

CONCLUSIONS

There was a significant reduction in inappropriate CDI testing following the implementation of the order set. There was an observed increase in the proportion of patients who underwent recent gastrointestinal surgery which may have contributed to the increase in 30-day readmission rates during the post-implementation period.

An ultrasensitive genosensor for detection of toxigenic and non-toxigenic Clostridioides difficile based on a conserved sequence in surface layer protein coding gene

Clostridioides difficile (C. difficile) is the most common agent of antibiotic-associated diarrhea, leading to intestinal infection through the secretion of two major toxins. Not all strains of this bacterium are toxigenic, but some of them cause infection via their accessory virulence factors, such as surface layer protein (SlpA). SlpA is conserved in both toxigenic and non-toxigenic strains of C. difficile. In the present work, an amplification-free electrochemical genosensor was designed for the detection of the slpA gene. A glassy carbon electrode coated with gold nanoparticle-reduced graphene oxide nanocomposite was used as the working electrode, and its surface was modified using a simple thiolated linear oligonucleotide as the bioreceptor. Moreover, the hexaferrocenium tri[hexa(isothiocyanato) iron(III)] trihydroxonium (HxFc) complex was used as an intercalator, and its redox signal was recorded using differential pulse voltammetry. Scan rate studies indicated a quasi-reversible adsorption-controlled process for the HxFc complex. This genosensor showed high sensitivity with a limit of detection of 0.2 fM, a linear response range of 0.46-1900 fM, and a satisfactory specificity toward the synthetic slpA target gene. Also, the genosensor indicated responses in the mentioned linear range toward the genome extracted from either toxigenic or non-toxigenic strains of C. difficile.

A review of fecal microbiota, live-jslm for the prevention of recurrent Clostridioides difficile infection

PURPOSE

To review the composition, preparation, proposed mechanism of action, safety, efficacy, and current place in therapy of Rebyota (fecal microbiota, live-jslm).

SUMMARY

As the first agent in a new class of drugs, live biotherapeutic products (LBPs), fecal microbiota, live-jslm offers another therapeutic approach for the prevention of recurrent Clostridioides difficile infection (rCDI). LBPs are given following antibiotic therapy for C. difficile to reintroduce certain bacteria present in the normal microbiome, as a means to reconstitute the microbiome of infected individuals. This review provides a summary of phase 2 and 3 clinical trials, product information, discussion of data limitations, and recommendations for place in therapy. High efficacy rates compared to placebo with sustained response up to 24 months after administration have been reported. The majority of adverse events identified were mild to moderate without significant safety signals.

CONCLUSION

Fecal microbiota, live-jslm has consistently been shown in randomized trials to be safe and effective in reducing rCDI. Its approval marks the culmination of decades of work to identify, characterize, and refine the intestinal microbiome to create pharmaceutical products.

Comparative evaluation of the STANDARD M10 and Xpert C. difficile assays for detection of toxigenic Clostridioides difficile in stool specimens

This study compared the performance of two commercial molecular assays, the STANDARD M10 Clostridioides difficile assay (M10) and the Xpert C. difficile assay (Xpert), for detecting toxigenic C. difficile in stool specimens. A total of 487 consecutive stool specimens submitted for routine C. difficile testing between June and November 2023 were included. Following routine testing using C. DIFF QUIK CHEK COMPLETE (QCC), M10 and Xpert were tested in parallel, alongside toxigenic culture (reference standard). Additionally, two-step algorithms, using QCC on the first step and either M10 or Xpert on the second step, were assessed. Both M10 and Xpert demonstrated a sensitivity and negative predictive value (NPV) of 100%. M10 exhibited significantly higher specificity and positive predictive value (PPV; 91.9% and 64.2%, respectively) than Xpert (90.3% and 59.8%, respectively). Both two-step algorithms showed a sensitivity and NPV of 98.4% and 99.8%, respectively. The specificity and PPV of the two-step algorithm using M10 (95.2% and 75.0%, respectively) were slightly higher than those of the one using Xpert (94.8% and 73.2%, respectively), without statistical significance. Receiver operating characteristic curve analysis, assessing the predictive ability of cycle threshold (Ct) values for the detection of free toxin, exhibited an area under the curve of 0.825 for M10 and 0.843 for Xpert. This indicates the utility of Ct values as predictors for the detection of free toxin in both assays. In conclusion, M10 proves to be an effective diagnostic tool with performance comparable to Xpert, whether utilized independently or as part of a two-step algorithm.

Reducing Clostridioides difficile Infections in a Medical Intensive Care Unit: A Multimodal Quality Improvement Initiative

BACKGROUND

Clostridioides difficile (C. diff) infection causes significant morbidity for hospitalized patients. A large medical intensive care unit had an increase in C. diff infection rates.

OBJECTIVES

The aim of this project was to reduce the C. diff polymerase chain reaction (PCR) test positivity rate and the rate of C. diff PCR tests ordered. Rates were compared between preintervention (July 2017 to December 2019) and postintervention (January 2021 to December 2022) timeframes.

METHODS

Unit leadership led a robust quality improvement project, including use of quality improvement tools such as A3, Gemba walks, and plan-do-study-act cycles. Interventions were tailored to the barriers identified, including standardization of in-room supply carts; use of single-packaged oral care kits; new enteric precautions signage; education to staff, providers, and visitors; scripting for patients and visitors; and use of a C. diff testing algorithm. Statistical process control charts were used to assess for improvements.

RESULTS

The average rate of C. diff PCR test positivity decreased from 34.9 PCR positive tests per 10 000 patient days to 12.3 in the postintervention period, a 66% reduction. The average rate of PCR tests ordered was 28 per 1000 patient days in the preintervention period; this decreased 44% to 15.7 in the postintervention period.

DISCUSSION

We found clinically significant improvements in the rate of C. diff infection and PCR tests ordered as a result of implementing tailored interventions in a large medical intensive care unit. Other units should consider using robust quality improvement methods and tools to conduct similar initiatives to reduce patient harm and improve care and outcomes.

Usefulness of Capillary Gel Electrophoresis-Based PCR for Detection of Clostridioides difficile Strains with Hypervirulent Ribotypes

Clostridioides difficile is a complex of anaerobic bacteria responsible for the epidemics of post-antibiotic diarrhea as one of the examples of CDI (Clostridioides difficile infection). As many as 70% of cases concern hospitalized patients, particularly those in intensive care units. Ribotyping is one of the most common methods for differentiating bacterial strains. The purpose of this work was to show the effectiveness of the gel electrophoresis-based PCR ribotyping method and the Webribo database for typing C. difficile isolates, including the hypervirulent 027 ribotype. DNA samples extracted from 69 C. difficile strains with previously marked genotypes were included in this study. PCR was performed using 16S-23S primers, and capillary gel electrophoresis was performed on the Applied Biosystem 3130xl Genetic Analyzer. The Webribo database was applied for ribotype assignment. Out of 69 samples, 48 belonged to already known ribotypes, 13 represented new ribotypes and 8 was indicated as similar to the existing ones, having some differences. Capillary gel electrophoresis-based PCR is an effective method for the differentiation of C. difficile ribotypes and can be recognized as a very useful tool in epidemiological studies, while the Webribo database is a useful and an accessible database for a quick analysis of C. difficile ribotypes.

Use of electronic health record data to identify hospital-associated Clostridioides difficile infections: a validation study

Background

Clinical research focused on the burden and impact of Clostridioides difficile infection (CDI) often relies upon accurate identification of cases using existing health record data. Use of diagnosis codes alone can lead to misclassification of cases. Our goal was to develop and validate a multi-component algorithm to identify hospital-associated CDI (HA-CDI) cases using electronic health record (EHR) data.

Methods

We performed a validation study using a random sample of adult inpatients at a large academic hospital setting in Portland, Oregon from January 2018 to March 2020. We excluded patients with CDI on admission and those with short lengths of stay (< 4 days). We tested a multi-component algorithm to identify HA-CDI; case patients were required to have received an inpatient course of metronidazole, oral vancomycin, or fidaxomicin and have at least one of the following: a positive C. difficile laboratory test or the International Classification of Diseases, Tenth Revision (ICD-10) code for non-recurrent CDI. For a random sample of 80 algorithm-identified HA-CDI cases and 80 non-cases, we performed manual EHR review to identify gold standard of HA-CDI diagnosis. We then calculated overall percent accuracy, sensitivity, specificity, and positive and negative predictive value for the algorithm overall and for the individual components.

Results

Our case definition algorithm identified HA-CDI cases with 94% accuracy (95% Confidence Interval (CI): 88% to 97%). We achieved 100% sensitivity (94% to 100%), 89% specificity (81% to 95%), 88% positive predictive value (78% to 94%), and 100% negative predictive value (95% to 100%). Requiring a positive C. difficile test as our gold standard further improved diagnostic performance (97% accuracy [93% to 99%], 93% PPV [85% to 98%]).

Conclusions

Our algorithm accurately detected true HA-CDI cases from EHR data in our patient population. A multi-component algorithm performs better than any isolated component. Requiring a positive laboratory test for C. difficile strengthens diagnostic performance even further. Accurate detection could have important implications for CDI tracking and research.

Inflammatory bowel disease and Clostridium difficile infection: clinical presentation, diagnosis, and management

As a frequent complication of inflammatory bowel disease (IBD), Clostridium difficile infection (CDI) was confirmed to not only aggravate the symptoms of IBD but also result in unexpected outcomes, including death. With the increasing prevalence rate of IBD and the updating of CDI diagnosis, the incidence of CDI in IBD patients is also seen rising. Although a detection method consisting of glutamate dehydrogenase immunoassay or nucleic acid amplification test and then toxin A/B enzyme immunoassay was recommended and widely adopted, the diagnosis of CDI in IBD is still a challenge because of the overlap between the symptoms of CDI in IBD and CDI itself. Vancomycin and fidaxomicin are the first-line therapy for CDI in IBD; however, the treatment has different effects due to the complexity of IBD patients' conditions and the choice of different treatment schemes. Although the use of fecal microbial transplantation is now in the ascendant for IBD management, the prospects are still uncertain and the prevention and treatment of the recurrence of CDI in IBD remain a clinical challenge. In this paper, the epidemiology, pathophysiology, clinical manifestation, prevention, and therapy of CDI in IBD were summarized and presented.

Deep learning-guided discovery of an antibiotic targeting Acinetobacter baumannii

Acinetobacter baumannii is a nosocomial Gram-negative pathogen that often displays multidrug resistance. Discovering new antibiotics against A. baumannii has proven challenging through conventional screening approaches. Fortunately, machine learning methods allow for the rapid exploration of chemical space, increasing the probability of discovering new antibacterial molecules. Here we screened ~7,500 molecules for those that inhibited the growth of A. baumannii in vitro. We trained a neural network with this growth inhibition dataset and performed in silico predictions for structurally new molecules with activity against A. baumannii. Through this approach, we discovered abaucin, an antibacterial compound with narrow-spectrum activity against A. baumannii. Further investigations revealed that abaucin perturbs lipoprotein trafficking through a mechanism involving LolE. Moreover, abaucin could control an A. baumannii infection in a mouse wound model. This work highlights the utility of machine learning in antibiotic discovery and describes a promising lead with targeted activity against a challenging Gram-negative pathogen.

Estimating the effect of active detection and isolation on Clostridioides difficile infections in a bone marrow transplant unit

OBJECTIVE

To model the effects of active detection and isolation (ADI) regarding Clostridioides difficile infection (CDI) in the bone marrow transplant (BMT) unit of our hospital.

SETTING

ADI was implemented in a 21-patient bone marrow unit.

PATIENTS

Patients were bone marrow recipients on this unit.

INTERVENTIONS

We compared active ADI, in which patients who tested positive for colonization of C. difficile before their hospital stay were placed under extra contact precautions, with cases not under ADI.

RESULTS

Within the BMT unit, ADI reduced total cases of CDI by 24.5% per year and reduced hospital-acquired cases by ∼84%. The results from our simulations also suggest that ADI can save ∼$67,600 per year in healthcare costs.

CONCLUSIONS

Institutions with active BMT units should consider implementing ADI.

Clostridioides (Clostridium) difficile: A silent nosocomial pathogen

Clostridioides difficile (C. difficile) infection is still a threat to many healthcare settings worldwide. Clostridioides difficile epidemiology has changed over the last 20 years, largely due to the emergence of hypervirulent and antimicrobial-resistant C. difficile strains. The excessive use of antimicrobials, the absence of optimal antibiotic policies, and suboptimal infection control practices have fueled the development of this pressing health issue. The prudent use of antimicrobials, particularly broad-spectrum agents, and simple infection control measures, such as hand hygiene, can significantly reduce C. difficile infection rates. Moreover, the early detection of these infections and understanding their epidemiological behavior using accurate laboratory methods are the cornerstone to decreasing the incidence of C. difficile infection and preventing further spread. Although there is no consensus on the single best laboratory method for the diagnosis of C. difficile infection, the use of 2 or more techniques can improve diagnostic accuracy, and it is recommended.

Effect of the COVID-19 Pandemic on Rates and Epidemiology of Clostridioides difficile Infection in One VA Hospital

The COVID-19 pandemic was associated with increases in some healthcare-associated infections. We investigated the impact of the pandemic on the rates and molecular epidemiology of Clostridioides difficile infection (CDI) within one VA hospital. We anticipated that the potential widespread use of antibiotics for pneumonia during the pandemic might increase CDI rates given that antibiotics are a major risk for CDI. Hospital data on patients with CDI and recurrent CDI (rCDI) were reviewed both prior to the COVID-19 pandemic (2015 to 2019) and during the pandemic (2020-2021). Restriction endonuclease analysis (REA) strain typing was performed on CD isolates recovered from stool samples collected from October 2019 to March 2022. CDI case numbers declined by 43.2% in 2020 to 2021 compared to the annual mean over the previous 5 years. The stool test positivity rate was also lower during the COVID-19 pandemic (14.3% vs. 17.2%; p = 0.013). Inpatient hospitalization rates declined, and rates of CDI among inpatients were reduced by 34.2% from 2020 to 2021. The mean monthly cases of rCDI also declined significantly after 2020 [3.38 (95% CI: 2.89-3.87) vs. 1.92 (95% CI: 1.27-2.56); p = <0.01]. Prior to the pandemic, REA group Y was the most prevalent CD strain among the major REA groups (27.3%). During the first wave of the pandemic, from 8 March 2020, to 30 June 2020, there was an increase in the relative incidence of REA group BI (26.7% vs. 9.1%); After adjusting for CDI risk factors, a multivariable logistic regression model revealed that the odds of developing an REA group BI CDI increased during the first pandemic wave (OR 6.41, 95% CI: 1.03-39.91) compared to the pre-pandemic period. In conclusion, the incidence of CDI and rCDI decreased significantly during the COVID-19 pandemic. In contrast, REA BI (Ribotype 027), a virulent, previously epidemic CD strain frequently associated with hospital transmission and outbreaks, reappeared as a prevalent strain during the first wave of the pandemic, but subsequently disappeared, and overall CDI rates declined.

Clostridioides difficile Near-Patient Testing Versus Centralized Testing: A Pragmatic Cluster Randomized Crossover Trial

BACKGROUND

Management of suspected Clostridioides difficile infection (CDI) in the hospital setting typically results in patient isolation, laboratory testing, infection control, and presumptive treatment. We investigated whether implementation of rapid near-patient testing (NPT) reduced patient isolation time, hospital length of stay (LOS), antibiotic usage, and cost.

METHODS

A 2-period pragmatic cluster randomized crossover trial was conducted. Thirty-nine wards were randomized into 2 study arms. The primary outcome measure was effect of NPT on patient isolation time using a mixed-effects generalized linear regression model. Secondary outcomes examined were hospital LOS and antibiotic therapy based on a negative binomial regression model. Natural experiment (NE), intention-to-treat (ITT), and per-protocol (PP) analyses were conducted.

RESULTS

During the entire study period, a total of 656 patients received NPT for CDI and 1667 received standard-of-care testing. For the primary outcome, a significant decrease of patient isolation time with NPT was observed (NE, 9.4 hours [P < .01]; ITT, 2.3 hours [P < .05]; PP, 6.7 hours [P < .1]). A significant reduction in hospital LOS was observed with NPT for short stay (NE, 47.4% [P < .01]; ITT, 18.4% [P < .01]; PP, 34.2% [P < .01]). Each additional hour delay for a negative result increased metronidazole use (24 defined daily doses per 1000 patients; P < .05) and non-CDI-treating antibiotics by 70.13 mg (P < .01). NPT was found to save 25.48 US dollars per patient when including test cost to the laboratory and patient isolation in the hospital.

CONCLUSIONS

This pragmatic cluster randomized crossover trial demonstrated that implementation of CDI NPT can contribute to significant reductions in isolation time, hospital LOS, antibiotic usage, and healthcare cost. Clinical Trials Registration. NCT03857464.

Syndromic Panel Testing Among Patients With Infectious Diarrhea: The Challenge of Interpreting Clostridioides difficile Positivity on a Multiplex Molecular Panel

Background

Including Clostridioides difficile (CD) in gastrointestinal multiplex molecular panels (GIPCR) presents a diagnostic challenge. Incidental detection by polymerase chain reaction (PCR) without consideration of pretest probability (PTP) may inadvertently delay diagnoses of other treatable causes of diarrhea and lead to prescription of unnecessary antibiotics.

Methods

We conducted a retrospective study to determine the frequency at which clinicians characterize PTP and disease severity in adult patients who test positive for CD by GIPCR. We organized subjects into cohorts based on the status of their CD PCR, glutamate dehydrogenase enzyme immunoassay (GDH), and toxin A/B detection, as well as by high, moderate, or low CD PTP. We used multivariable regression models to describe predictors of toxin positivity.

Results

We identified 483 patients with positive CD PCR targets. Only 22% were positive for both GDH and CD toxin. Among patients with a low PTP for CDI, 11% demonstrated a positive CD toxin result compared to 63% of patients with a high PTP. A low clinician PTP for CD infection (CDI) correlated with a negative CD toxin result compared to cases of moderate-to-high PTP for CDI (odds ratio, 0.19 [95% confidence interval, .10-.36]). Up to 64% of patients with negative GDH and CD toxin received CD treatment. Only receipt of prior antibiotics, fever, and a moderate-to-high clinician PTP were statistically significant predictors of toxin positivity.

Conclusions

Patients with a positive CD PCR were likely to receive treatment regardless of PTP or CD toxin results. We recommend that CD positivity on GIPCR be interpreted with caution, particularly in the setting of a low PTP.

Leveraging diagnostic stewardship within antimicrobial stewardship programmes

Novel diagnostic stewardship in infectious disease consists of interventions that modify ordering, processing, and reporting of diagnostic tests to provide the right test for the right patient, prompting the right action. The interventions work upstream and synergistically with traditional antimicrobial stewardship efforts. As diagnostic stewardship continues to gain public attention, it is critical that antimicrobial stewardship programmes not only learn how to effectively leverage diagnostic testing to improve antimicrobial use but also ensure that they are stakeholders and leaders in developing new diagnostic stewardship interventions within their institutions. This review will discuss the need for diagnostic and antimicrobial stewardship, the interplay of diagnostic and antimicrobial stewardship, evidence of benefit to antimicrobial stewardship programmes, and considerations for successfully engaging in diagnostic stewardship interventions. This article is part of the Antibiotic stewardship Special Issue: https://www.drugsincontext.com/special_issues/antimicrobial-stewardship-a-focus-on-the-need-for-moderation.

A rapid multiplex real-time PCR detection of toxigenic Clostridioides difficile directly from fecal samples

This study developed a new single-tube multiplex real-time PCR method for detecting toxigenic C. difficile directly from fecal samples using tcdA, tcdB, cdtB, and internal gene tpi as targets, which could be performed on kinds of polymerase chain reaction device including point-of-care testing (POCT), with improved detection efficiency. The specificity, sensitivity, and repeatability of each gene was evaluated using 69 C. difficile isolates and 74 fecal samples. Results were compared with established PCR, qPCR, and ELISA methods. Interspecies specificity was 100% based on six common intestinal pathogens (Escherichia coli, Enterococcus Faecium, Enterococcus faecalis, Clostridium perfringens, Bacteroides fragilis, Clostridium botulinum). The lower detection limit (LDL) for tcdA, tcdB, and cdtB with pure C. difficile DNA was 10¹,10⁰, and 10⁰ copies/μL, respectively, the coefficients of variation among different experimental batches and within each experimental batch were both less than 3%, which shows that this method has strong repeatability. And the LDL of fecal DNA was 5 × 10⁰, 5 × 10³, and 5 × 10² colony-forming units (CFU)/g, respectively. In addition, the efficiency for detection of tcdA was compared with established PCR and real-time PCR methods, demonstrating high consistency (98.4%) and similar sensitivity. ELISA was used to confirm inconsistent results, which were identical with our method. The sensitivity and specificity for detecting toxigenic C. difficile in fecal samples were 96.49% and 94.12% compared with the toxigenic culture (TC). This method effectively identified the toxigenic and non-toxigenic strains with high specificity, sensitivity, and repeatability, and could reduce the false positive rate of tcdA, and accurately identify the typical Asian strain RT017, making it potentially contribute to the surveillance of CDI in China.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-022-03434-6.

Recommendations for change in infection prevention programs and practice

Fifty years of evolution in infection prevention and control programs have involved significant accomplishments related to clinical practices, methodologies, and technology. However, regulatory mandates, and resource and research limitations, coupled with emerging infection threats such as the COVID-19 pandemic, present considerable challenges for infection preventionists. This article provides guidance and recommendations in 14 key areas. These interventions should be considered for implementation by United States health care facilities in the near future.

Clostridioides difficile as a Potential Pathogen of Importance to One Health: A Review

Clostridioides difficile (basonym Clostridium) is a bacterial enteropathogen associated with cases of C. difficile infection that can result in pseudomembranous colitis, rapid fluid loss, and death. For decades following its isolation, C. difficile was thought to be a solely nosocomial pathogen, being isolated from individuals undergoing antimicrobial therapy and largely affecting elderly populations. More recently, C. difficile spores have been identified in the broader environment, including in food-producing animals, soil, and food matrices, in both ready-to-eat foods and meat products. Furthermore, evidence has emerged of hypervirulent ribotypes (RTs), such as RT078, similar to those cultured in asymptomatic carriers, also being identified in these environments. This finding may reflect on adaptations arising in these bacteria following selection pressures encountered in these niches, and which occurs due to an increase in antimicrobial usage in both clinical and veterinary settings. As C. difficile continues to adapt to new ecological niches, the taxonomy of this genus has also been evolving. To help understand the transmission and virulence potential of these bacteria of importance to veterinary public health, strategies applying multi-omics-based technologies may prove useful. These approaches may extend our current understanding of this recognized nosocomial pathogen, perhaps redefining it as a zoonotic bacterium. In this review, a brief background on the epidemiological presentation of C. difficile will be highlighted, followed by a review of C. difficile in food-producing animals and food products. The current state of C. difficile taxonomy will provide evidence of Clade 5 (ST11/RT078) delineation, as well as background on the genomic elements linked to C. difficile virulence and ongoing speciation. Recent studies applying second- and third-generation sequencing technologies will be highlighted, and which will further strengthen the argument made by many throughout the world regarding this pathogen and its consideration within a One Health dimension.

An interprofessional approach to reducing hospital-onset Clostridioides difficile infections

BACKGROUND

Clostridioides difficile is the most prevalent hospital-onset (HO) infection. There are significant financial and safety impacts associated with HO-C. difficile infections (HO-CDIs) for both patients and health care organizations. The incidence of HO-CDIs at our community hospital within an academic acute health care system was continuously above the national benchmark.

METHODS

In response to the high HO-CDI rates at our facility, an interprofessional team selected evidence-based interventions with the goal of reducing HO-CDI incidence rates. Interventions included: diagnostic stewardship, enhanced environmental cleaning, antimicrobial stewardship and education and accountability.

RESULTS

After one year, we achieved a 63% reduction in HO-CDI and have sustained a 77% reduction. The infection rate remained below national benchmark for HO-CDI for over 4 years at a rate of 2.80 per 10,000 patient days and a SIR of 0.43 in 2020.

DISCUSSION

Multiple evidence-based interventions were successfully implemented over several service lines over a 4-year period through the collaboration of an interprofessional team. The addition of an accountability processes further improved compliance with standards of practice.

CONCLUSIONS

Collaboration of an interprofessional team led to substantial and sustained reductions in HO-CDI.

Clostridioides Difficile Infection before and during Coronavirus Disease 2019 Pandemic-Similarities and Differences

The aim of this study was to investigate the differences of Clostridioides difficile infection (CDI) during the COVID-19 pandemic compared to the pre-COVID-19 era. CDI patients treated at the Clinic for Infectious Diseases, Clinical Center of Vojvodina, Serbia during 2017-2019 (n = 304) were compared with COVID-19/CDI patients treated in period September 2021-September 2022 (n = 387). Groups were compared by age, gender, comorbidities, previous medications, laboratory findings, and outcome within 30 days. In the CDI/COVID-19 group, we found: greater percentage of males 59.8% vs. 42.6% (p ≤ 0.001), older age 72.8 ± 9.4 vs. 65.6 ± 11.7 (p ≤ 0.001), higher Charlson comorbidity score (CCS) (3.06 ± 1.54 vs. 2.33 ± 1.34 (p ≤ 0.001), greater percentage of chronic renal failure (33.9% vs. 23.4% (p = 0.003), malignances (24.3% vs. 13.5% (p ≤ 0.001), chronic obstructive pulmonary disease (22.7% vs. 15.5% (p = 0.017), higher usage of macrolide (38.5% vs. 8.6% (p ≤ 0.001), greater percentage of patients with hypoalbuminemia ≤25 g/L (19.6% vs. 12.2% (p ≤ 0.001), lower percentage of patients with elevated creatinine (≥200 mmol/L) (31.5% vs. 43.8%) (p = 0.002), and greater percentage of lethal outcome 29.5% vs. 6.6% (p ≤ 0.001). In the prediction of lethal outcome multivariate regression analysis extracted as an independent predictor, only higher CRP values in the non-COVID-19 group and in the COVID-19 group: older age (p ≤ 0.001), CCS (p = 0.019) and CRP (p = 0.015). COVID-19 changes the disease course of CDI and should be taken into consideration when managing those patients.

Gut Microbiota and Clostridium difficile: What We Know and the New Frontiers

Our digestive system, particularly our intestines, harbors a vast amount of microorganisms, whose genetic makeup is referred to as the microbiome. Clostridium difficile is a spore-forming Gram-positive bacterium, which can cause an infection whose symptoms range from asymptomatic colonization to fearsome complications such as the onset of toxic megacolon. The relationship between gut microbiota and Clostridium difficile infection has been studied from different perspectives. One of the proposed strategies is to be able to specifically identify which types of microbiota alterations are most at risk for the onset of CDI. In this article, we understood once again how crucial the role of the human microbiota is in health and especially how crucial it becomes, in the case of its alteration, for the individual's disease. Clostridium difficile infection is an emblematic example of how a normal and physiological composition of the human microbiome can play a very important role in immune defense against such a fearsome disease.

Clostridioides difficile infection recurrence in the VINC at hospitals: a prospective observational cohort study

Background: The 2016 cumulative incidence of Clostridioides difficile infection (CDI) in Spain was reported by the European Center for Disease Control to be above the mean of other European countries. The aim of this multicenter prospective observational cohort study was to examine the risk factors that determine 90-day CDI recurrence in Catalonia, Spain. Methods: The study included 558 consecutive adults admitted to hospital who had a symptomatic, first positive CDI diagnosis. Sociodemographic, clinical and epidemiological variables were recorded. The primary outcome was 90-day CDI recurrence. Results: In this Catalan population, having received more than one course of antibiotics in the 30 days prior to CDI diagnosis (odds ratio: 2.459; 95% CI: 1.195–5.060; p = 0.015) and active chemotherapy (odds ratio: 4.859; 95% CI: 1.495–15.792; p = 0.009) are significant predictors of 90-day CDI recurrence. Conclusion: The identification of independent risk factors of 90-day CDI recurrence will enable the optimization of preventive measures in at-risk populations.

Phage-tail-like bacteriocins as a biomedical platform to counter anti-microbial resistant pathogens

Phage Tail Like bacteriocins (PTLBs) has been an area of interest in the last couple of years owing to their varied application against multi-drug resistant (MDR), anti-microbial resistant (AMR) pathogens and their evolutionary link with the dsDNA virus and bacteriophages. PTLBs are defective phages derived from Myoviridae and Siphoviridae phages, PTLBs are distinguished into R-type (Rigid type) characterized by a non-flexible contractile nanotube resembling Myoviridae phage contractile tails, and F-type (Flexible type) with a flexible non-contractile rod-like structure similar to Siphoviridae phages. In this review, we have discussed the structural association, mechanism, and characterization of PTLBs. Moreover, we have elucidated the symbiotic biological function and application of PTLBs against MDR and XDR pathogens and highlighted the evolutionary role of PTLBs. The difficulties that must be overcome to implement PTLBs clinically are also discussed. It is imperative that these issues be addressed by academics in future studies before being implemented in clinical settings. This article is novel in its way as it will not only provide us with a gateway that acts as a novel strategy for scholars to mitigate and control the uprising issue of AMR pathogens but also promote the development of clinical studies for PTLBs.

Clinical Presentations, Predictive Factors, and Outcomes of Clostridioides difficile Infection among COVID-19 Hospitalized Patients—A Single Center Experience from the COVID Hospital of the University Clinical Center of Vojvodina, Serbia

Background: This study aimed to investigate the clinical form, risk factors, and outcomes of patients with COVID-19 and Clostridioides difficile co-infections. Methods: This retrospective study (2 September 2021-1 April 2022) included all patients with Clostridioides difficile infection (CDI) and COVID-19 infection who were admitted to the Covid Hospital of the University Clinical Center of Vojvodina. Results: A total of 5124 COVID-19 patients were admitted to the Covid Hospital, and 326 of them (6.36%) developed hospital-onset CDI. Of those, 326 of the CDI patients (88.65%) were older than 65 years. The median time of CDI onset was 12.88 days. Previous hospitalizations showed 69.93% of CDI patients compared to 38.81% in the non-CDI group (p = 0.029). The concomitant antibiotics exposure was higher among the CDI group versus the non-CDI group (88.65% vs. 68.42%, p = 0.037). Albumin levels were ≤ 25 g/L among 39.57% of the CDI patients and 21.71% in the non-CDI patients (p = 0.021). The clinical manifestations of CDI ranged from mild diarrhea (26.9%) to severe diarrhea (63.49%) and a complicated form of colitis (9.81%). Regarding outcomes, 79.14% of the CDI patients recovered and 20.86% had fatal outcomes in-hospital. Although a minority of the patients were in the non-CDI group, the difference in mortality rate between the CDI and non-CDI group was not statistically significant (20.86% vs. 15.13%, p = 0.097). Conclusions: Elderly patients on concomitant antibiotic treatments with hypoalbuminemia and with previous healthcare exposures were the most affected by COVID-19 and CD co-infections.

Risk of antibiotics associated with Clostridioides difficile infection: Antibiotic stewardship in action

We examined risk associated with antibiotics used for Clostridioides difficile infection (CDI) at a single site from 2018 through 2020. Overall, 78 patients had nonrecurrent infections. Among inpatient antibiotics, intravenous meropenem had the highest CDI rate (3.56 per 1,000 days of therapy; n = 2 cases). Among outpatient antibiotics, metronidazole had the highest rate (0.071 per 1,000 pills dispensed; n = 3 cases).

The value of fecal calprotectin in Clostridioides difficile infection: A systematic review

As a marker of inflammation, calprotectin has potential application value in a variety of inflammatory diseases, such as arthritis and bacterial infections. Clostridioides difficile infection (CDI) is an infectious disease that causes intestinal damage and inflammation. This systematic review aims to determine whether fecal calprotectin has application value in CDI. Nine databases were searched from inception to 6 June 2022, and 17 studies were included. These studies were divided into four groups according to their content. Generally speaking, fecal calprotectin is not an ideal indicator for the diagnosis and prognosis prediction of CDI but may serve as a potential indicator for assessing disease severity and as a readily detectable marker for CDI screening. In addition, patients in need of treatment or with detectable toxins in stool may tend to have higher levels of fecal calprotectin. In summary, fecal calprotectin has some potential application value in CDI. However, further studies are needed to verify these findings and determine the reliability of calprotectin as a biomarker for CDI.

Efficacy and Outcomes of Faecal Microbiota Transplantation for Recurrent Clostridioides difficile Infection in Children with Inflammatory Bowel Disease

BACKGROUND

Children with inflammatory bowel disease [IBD] are disproportionally affected by recurrent Clostridioides difficile infection [rCDI]. Although faecal microbiota transplantation [FMT] has been used with good efficacy in adults with IBD, little is known about outcomes associated with FMT in paediatric IBD.

METHODS

We performed a retrospective review of FMT at 20 paediatric centres in the USA from March 2012 to March 2020. Children with and without IBD were compared with determined differences in the efficacy of FMT for rCDI. In addition, children with IBD with and without a successful outcome were compared with determined predictors of success. Safety data and IBD-specific outcomes were obtained.

RESULTS

A total of 396 paediatric patients, including 148 with IBD, were included. Children with IBD were no less likely to have a successful first FMT then the non-IBD affected cohort [76% vs 81%, p = 0.17]. Among children with IBD, patients were more likely to have a successful FMT if they received FMT with fresh stool [p = 0.03], were without diarrhoea prior to FMT [p = 0.03], or had a shorter time from rCDI diagnosis until FMT [p = 0.04]. Children with a failed FMT were more likely to have clinically active IBD post-FMT [p = 0.002] and 19 [13%] patients had an IBD-related hospitalisation in the 3-month follow-up.

CONCLUSIONS

Based on the findings from this large US multicentre cohort, the efficacy of FMT for the treatment of rCDI did not differ in children with IBD. Failed FMT among children with IBD was possibly related to the presence of clinically active IBD.

Bring it on: Top five antimicrobial stewardship challenges in transplant infectious diseases and practical strategies to address them

Antimicrobial therapies are essential tools for transplant recipients who are at high risk for infectious complications. However, judicious use of antimicrobials is critical to preventing the development of antimicrobial resistance. Treatment of multidrug-resistant organisms is challenging and potentially leads to therapies with higher toxicities, intravenous access, and intensive drug monitoring for interactions. Antimicrobial stewardship programs are crucial in the prevention of antimicrobial resistance, though balancing these strategies with the need for early and frequent antibiotic therapy in these immunocompromised patients can be challenging. In this review, we summarize 5 frequently encountered transplant infectious disease stewardship challenges, and we suggest strategies to improve practices for each clinical syndrome. These 5 challenging areas are: asymptomatic bacteriuria in kidney transplant recipients, febrile neutropenia in hematopoietic stem cell transplantation, antifungal prophylaxis in liver and lung transplantation, treatment of left-ventricular assist device infections, and Clostridioides difficile infection in solid-organ and hematopoietic stem-cell transplant recipients. Common themes contributing to these challenges include limited data specific to transplant patients, shortcomings in diagnostic testing, and uncertainties in pharmacotherapy.

Clostridioides difficile infection and One Health: An Equine Perspective

Clostridioides (Clostridium) difficile presents a significant health risk to humans and animals. The complexity of the bacterial–host interaction affecting pathogenesis and disease development creates an ongoing challenge for epidemiological studies, control strategies and prevention planning. The recent emergence of human disease caused by strains of C. difficile found in animals adds to mounting evidence that C. difficile infection (CDI) may be a zoonosis. In equine populations, C. difficile is a known cause of diarrhoea and gastrointestinal inflammation, with considerable mortality and morbidity. This has a significant impact on both the well‐being of the animal and, in the case of performance and production animals, it may have an adverse economic impact on relevant industries. While C. difficile is regularly isolated from horses, many questions remain regarding the impact of asymptomatic carriage as well as optimization of diagnosis, testing and treatment. This review provides an overview of our understanding of equine CDI while also identifying knowledge gaps and the need for a holistic One Health approach to a complicated issue.

Clostridioides difficile: Current overview and future perspectives

The most common world-wide cause of antibiotic-associated infectious diarrhea and colitis is the toxin producing bacterium, Clostridioides difficile (C. difficile). Here we review the background and characteristics of the bacterium and the toxins produced together with the epidemiology and the complex pathogenesis that leads to a broad clinical spectrum of disease. The review describes the difficulties faced in obtaining a quick and accurate diagnosis despite the range of sensitive and specific diagnostic tools available. We also discuss the problem of disease recurrence and the importance of disease prevention. The high rates of infection recurrence mean that treatment strategies are constantly under review and we outline the diverse treatment options that are currently in use and explore the emerging treatment options of pulsed antibiotic use, microbial replacement therapies and the use of monoclonal antibodies. We summarize the future direction of treatment strategies which include the development of novel antibiotics, the administration of oral polyclonal antibody formulations, the use of vaccines, the administration of competitive non-toxigenic spores and the neutralization of antibiotics at the microbiota level. Future successful treatments will likely involve a combination of therapies to provide the most effective and robust approach to C. difficile management.

Did the severe acute respiratory syndrome-coronavirus 2 pandemic cause an endemic Clostridium difficile infection?

BACKGROUND

Clostridium difficile infection (CDI) has increased in prevalence during the last years. The coronavirus disease 2019 (COVID-19) pandemic has negatively influenced patient outcomes. The majority of the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2)-infected patients received antibiotics during hospitalization.

AIM

To analyze the factors that influenced CDI development after SARS-CoV-2 infection.

METHODS

Between March 2020 to December 2020, we performed a prospective observational study including 447 patients diagnosed with CDI who were admitted to our tertiary referral university hospital. The diagnosis of CDI was based on the presence of diarrhea (≥ 3 watery stools within 24 h) associated with Clostridium difficile toxins A or B. We excluded patients with other etiology of acute diarrhea.

RESULTS

Among the total 447 (12.5%) patients with CDI, most were male (54.3%) and mean age was 59.7 ± 10.8 years. Seventy-six (17.0%) had history of COVID-19, most being elderly (COVID-19: 62.6 ± 14.6 years vs non-COVID-19: 56.8 ± 17.6 years, P = 0.007), with history of alcohol consumption (43.4% vs 29.4%, P = 0.017), previous hospitalizations (81.6% vs 54.9%, P < 0.001) and antibiotic treatments (60.5% vs 35.5%, P < 0.001), requiring higher doses of vancomycin and prone to recurrent disease (25.0% vs 13.1%, P = 0.011). Age over 60 years [odds ratio (OR): 2.591, 95% confidence interval (CI): 1.452-4.624, P = 0.001], urban residence (OR: 2.330, 95%CI: 1.286-4.221, P = 0.005), previous antibiotic treatments (OR: 1.909, 95%CI: 1.083-3.365, P = 0.025), previous hospitalizations (OR: 2.509, 95%CI: 1.263-4.986, P = 0.009) and alcohol consumption (OR: 2.550, 95%CI: 1.459-4.459, P = 0.001) were risk factors of CDI in COVID-19.

CONCLUSION

CDI risk is unrelated to history of SARS-CoV-2 infection. However, previous COVID-19 may necessitate higher doses of vancomycin for CDI.

Management and characteristics of patients suffering from Clostridiodes difficile infection in primary care

Background

Clostridioides difficile infection (CDI) is rising and increases patient healthcare costs due to extended hospitalisation, tests and medications. Management of CDI in French primary care is poorly reported.

Objectives

To characterise patients suffering from CDI, managed in primary care and describe their clinical outcomes.

Methods

Retrospective observational study based on survey data among 500 randomly selected General Practitioners (GPs) surveyed in France from September 2018 to April 2019. GPs were asked to complete a multiple-choice questionnaire for each reported patient presenting a CDI. Responses were analysed according to clinical characteristics. Treatment strategies were compared according to the outcome: recovery or recurrent infection.

Results

Participation rate was 8.6% (n = 43/500) with two incomplete questionnaires. Data from 41 patients with an actual diagnosis of CDI were analysed. Recovery was observed in 61% of patients with a confirmed diagnosis of CDI. In the recovery group, this was exclusively a primary episode, most patients (72%) had no comorbidities, were significantly younger (p = 0.02) than the ones who relapsed and 92% were successfully treated with oral metronidazole. Duration of diarrhoea after antimicrobial treatment initiation was significantly shorter in the recovery group (≤ 48 h) (p = 0.03). Cooperation with hospital specialists was reported in 28% of the recovery group versus 87.5% of the recurrent group (p = 0.0003). Overall, GPs managed successfully 82.9% of cases without need of hospital admission.

Conclusion

GPs provide relevant ambulatory care for mild primary episodes of CDI using oral metronidazole. Persistent diarrhoea despite an appropriate anti-Clostridiodes regimen should be interpreted as an early predictor of relapse.

The Role of CD4+ T Cells and Microbiota in the Pathogenesis of Asthma

Asthma, a chronic respiratory disease involving variable airflow limitations, exhibits two phenotypes: eosinophilic and neutrophilic. The asthma phenotype must be considered because the prognosis and drug responsiveness of eosinophilic and neutrophilic asthma differ. CD4+ T cells are the main determinant of asthma phenotype. Th2, Th9 and Tfh cells mediate the development of eosinophilic asthma, whereas Th1 and Th17 cells mediate the development of neutrophilic asthma. Elucidating the biological roles of CD4+ T cells is thus essential for developing effective asthma treatments and predicting a patient's prognosis. Commensal bacteria also play a key role in the pathogenesis of asthma. Beneficial bacteria within the host act to suppress asthma, whereas harmful bacteria exacerbate asthma. Recent literature indicates that imbalances between beneficial and harmful bacteria affect the differentiation of CD4+ T cells, leading to the development of asthma. Correcting bacterial imbalances using probiotics reportedly improves asthma symptoms. In this review, we investigate the effects of crosstalk between the microbiota and CD4+ T cells on the development of asthma.