Recurrent Clostridium difficile infection is associated with increased mortality

Nonalcoholic Fatty Liver Disease-A Novel Risk Factor for Recurrent Clostridioides difficile Infection

Recurrent Clostridioides difficile infections (rCDI) have a substantial impact on healthcare systems, with limited and often expensive therapeutic options. Nonalcoholic fatty liver disease (NAFLD) affects about 25% of the adult population and is associated with metabolic syndrome, changes in gut microbiome and bile acids biosynthesis, all possibly related with rCDI. The aim of this study was to determine whether NAFLD is a risk factor associated with rCDI. A retrospective cohort study included patients ≥ 60 years hospitalized with CDI. The cohort was divided into two groups: those who were and were not readmitted with CDI within 3 months of discharge. Of the 329 patients included, 107 patients (32.5%) experienced rCDI. Patients with rCDI were older, had higher Charlson Age-Comorbidity Index (CACI) and were more frequently hospitalized within 3 months. Except for chronic kidney disease and NAFLD, which were more frequent in the rCDI group, there were no differences in other comorbidities, antibiotic classes used and duration of antimicrobial therapy. Multivariable Cox regression analysis showed that age >75 years, NAFLD, CACI >6, chronic kidney disease, statins and immobility were associated with rCDI. In conclusion, our study identified NAFLD as a possible new host-related risk factor associated with rCDI.

Identification of a Novel Regulator of Clostridioides difficile Cortex Formation

Clostridioides difficile is a leading cause of health care-associated infections worldwide. These infections are transmitted by C. difficile′s metabolically dormant, aerotolerant spore form. Functional spore formation depends on the assembly of two protective layers, a thick layer of modified peptidoglycan known as the cortex layer and a multilayered proteinaceous meshwork known as the coat. We previously identified two spore morphogenetic proteins, SpoIVA and SipL, that are essential for recruiting coat proteins to the developing forespore and making functional spores. While SpoIVA and SipL directly interact, the identities of the proteins they recruit to the forespore remained unknown. Here, we used mass spectrometry-based affinity proteomics to identify proteins that interact with the SpoIVA-SipL complex. These analyses identified the Peptostreptococcaceae family-specific, sporulation-induced bitopic membrane protein CD3457 (renamed SpoVQ) as a protein that interacts with SipL and SpoIVA. Loss of SpoVQ decreased heat-resistant spore formation by ∼5-fold and reduced cortex thickness ∼2-fold; the thinner cortex layer of ΔspoVQ spores correlated with higher levels of spontaneous germination (i.e., in the absence of germinant). Notably, loss of SpoVQ in either spoIVA or sipL mutants prevented cortex synthesis altogether and greatly impaired the localization of a SipL-mCherry fusion protein around the forespore. Thus, SpoVQ is a novel regulator of C. difficile cortex synthesis that appears to link cortex and coat formation. The identification of SpoVQ as a spore morphogenetic protein further highlights how Peptostreptococcaceae family-specific mechanisms control spore formation in C. difficile.

IMPORTANCE The Centers for Disease Control has designated Clostridioides difficile as an urgent threat because of its intrinsic antibiotic resistance. C. difficile persists in the presence of antibiotics in part because it makes metabolically dormant spores. While recent work has shown that preventing the formation of infectious spores can reduce C. difficile disease recurrence, more selective antisporulation therapies are needed. The identification of spore morphogenetic factors specific to C. difficile would facilitate the development of such therapies. In this study, we identified SpoVQ (CD3457) as a spore morphogenetic protein specific to the Peptostreptococcaceae family that regulates the formation of C. difficile’s protective spore cortex layer. SpoVQ acts in concert with the known spore coat morphogenetic factors, SpoIVA and SipL, to link formation of the protective coat and cortex layers. These data reveal a novel pathway that could be targeted to prevent the formation of infectious C. difficile spores.

Epidemiology of community-acquired and recurrent Clostridioides difficile infection

Clostridioides difficile infection is a leading cause of healthcare-associated infections with significant morbidity and mortality. For the past decade, the bulk of infection prevention and epidemiologic surveillance efforts have been directed toward mitigating hospital-acquired C. difficile. However, the incidence of community-associated infection is on the rise. Patients with community-associated C. difficile tend to be younger and have lower mortality rate. Rates of recurrent C. difficile infection overall have decreased in the United States, but future research and public health endeavors are needed to standardize and improve disease detection, stratify risk factors in large-scale population studies, and to identify regional and local variations in strain types, reservoirs and transmission routes to help characterize and combat the changing epidemiology of C. difficile.

Successful use of early, repeat fecal microbiota transplantation for initial treatment of severe, refractory Clostridioides difficile colitis

Purpose

There is a paucity of literature surrounding the use of early fecal microbiota transplantation (FMT) for patients presenting with an initial episode of severe, refractory Clostridioides difficile infection (CDI). Information on optimal antibiotic dosing and therapy duration surrounding FMT during an acute, initial episode of CDI is also limited. Described here is a case of successful treatment of CDI after 4 FMTs during an acute, initial episode of severe, refractory Clostridioides difficile colitis.

Summary

A 69-year-old community-dwelling, Caucasian male presented after 48 hours of vomiting and diarrhea. A stool sample was collected and resulted positive for Clostridioides difficile by both polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA). The patient was treated with several days of oral and rectal vancomycin therapy in addition to intravenous metronidazole, but those treatments failed. His clinical and nutrition status deteriorated over the course of several days until salvage therapy was ordered, with administration of 1 inpatient nasogastric FMT and 1 inpatient colonoscopic FMT followed by outpatient colonoscopic FMTs on 2 consecutive days within 2 weeks of hospital discharge.

Conclusion

This case suggests a role for early, repeat FMT during an initial presentation of a severe Clostridioides difficile colitis episode refractory to pharmacologic antimicrobial therapy. It also adds to emerging literature regarding the timing of antibiotic cessation surrounding FMT.

Faecalibacterium prausnitzii increases following fecal microbiota transplantation in recurrent Clostridioides difficile infection

OBJECTIVE

Fecal microbiota transplantation (FMT) is a highly effective treatment for Clostridioides difficile infection (CDI). However, the fecal transplant's causal components translating into clearance of the CDI are yet to be identified. The commensal bacteria Faecalibacterium prausnitzii may be of great interest in this context, since it is one of the most common species of the healthy gut microbiota and produces metabolites with anti-inflammatory properties. Although there is mounting evidence that F. prausnitzii is an important regulator of intestinal homeostasis, data about its role in CDI and FMT are relatively scarce.

METHODS

Stool samples from patients with recurrent CDI were collected to investigate the relative abundance of F. prausnitzii before and after FMT. Twenty-one patients provided fecal samples before the FMT procedure, at 2 weeks post-FMT, and at 2-4 months post-FMT. The relative abundance of F. prausnitzii was determined using quantitative polymerase chain reaction.

RESULTS

The abundance of F. prausnitzii was elevated in samples (N = 9) from donors compared to pre-FMT samples (N = 15) from patients (adjusted P<0.001). No significant difference in the abundance of F. prausnitzii between responders (N = 11) and non-responders (N = 4) was found before FMT (P = 0.85). In patients with CDI, the abundance of F. prausnitzii significantly increased in the 2 weeks post-FMT samples (N = 14) compared to the pre-FMT samples (N = 15, adjusted P<0.001). The increase persisted 2-4 months post-FMT (N = 15) compared to pre-FMT samples (N = 15) (adjusted P<0.001).

CONCLUSIONS

FMT increases the relative abundance of F. prausnitzii in patients with recurrent CDI, and this microbial shift remains several months later. The baseline abundance of F. prausnitzii in donors or recipients was not associated with future treatment response, although a true predictive capacity cannot be excluded because of the limited sample size. Further studies are needed to discern whether F. prausnitzii plays an active role in the resolution of CDI.

Microbiota-based Therapies Clostridioides difficile infection that is refractory to antibiotic therapy

Clostridioides difficile infection (CDI) has had a devastating impact worldwide with significant rates of mortality, especially among the elderly. Despite effective antibiotics, the incidence of recurrent CDI (rCDI) is increasing and more difficult to treat with antibiotics alone. Fecal Microbiota Transplantation (FMT) has emerged as a consistently effective treatment for rCDI. Mechanisms for FMT are not entirely understood, but remain an area of active investigation. There have been recent safety reports with the use of FMT regarding transmission of pathogens in a few patients that have led to serious illness. With appropriate screening, FMT can be safely administered and continue to have a significant impact on eradication of rCDI and improve the lives of patients suffering from this disease. In this review, we summarize current treatments for CDI with a focus on microbiota-based therapies used for antibiotic refractory disease.

Economic burden of recurrent Clostridioides difficile infection in adults admitted to Spanish hospitals. A multicentre retrospective observational study

OBJECTIVE

Clostridioides difficile infection (CDI) is associated with increased hospital stays and mortality and a high likelihood of rehospitalization, leading to increased health resource use and costs. The objective was to estimate the economic burden of recurrent CDI (rCDI).

METHODS

Observational, retrospective study carried out in six hospitals. Adults aged ≥18 years with ≥1 confirmed diagnosis (primary or secondary) of rCDI between January 2010 and May 2018 were included. rCDI-related resource use included days of hospital stay (emergency room, ward, isolation and ICU), tests and treatments. For patients with primary diagnosis of rCDI, the complete hospital stay was attributed to rCDI. When diagnosis of rCDI was secondary, hospital stay attributed to rCDI was estimated using 1:1 propensity score matching as the difference in hospital stay compared to controls. Controls were hospitalizations without CDI recorded in the Spanish National Hospital Discharge Database. The cost was calculated by multiplying the natural resource units by the unit cost. Costs (euros) were updated to 2019.

RESULTS

We included 282 rCDI episodes (188 as primary diagnosis): 66.31% of patients were aged ≥65 years and 57.80% were female. The mean hospital stay (SD) was 17.18 (23.27) days: 86.17% of rCDI episodes were isolated for a mean (SD) of 10.30 (9.97) days. The total mean cost (95%-CI) per episode was €10,877 (9,499-12,777), of which the hospital stay accounted for 92.56.

CONCLUSIONS

There is high cost and resource use associated with rCDI, highlighting the importance of preventing rCDI to the Spanish National Health System.

Prospective Study on Incidence, Risk Factors and Outcome of Recurrent Clostridioides difficile Infections

BACKGROUND

Limited and wide-ranging data are available on the recurrent Clostridioides difficile infection (rCDI) incidence rate.

METHODS

We performed a cohort study with the aim to assess the incidence of and risk factors for rCDI. Adult patients with a first CDI, hospitalized in 15 Italian hospitals, were prospectively included and followed-up for 30 d after the end of antimicrobial treatment for their first CDI. A case-control study was performed to identify risk factors associated with 30-day onset rCDI.

RESULTS

Three hundred nine patients with a first CDI were included in the study; 32% of the CDI episodes (99/309) were severe/complicated; complete follow-up was available for 288 patients (19 died during the first CDI episode, and 2 were lost during follow-up). At the end of the study, the crude all-cause mortality rate was 10.7% (33 deaths/309 patients). Two hundred seventy-one patients completed the follow-up; rCDI occurred in 21% of patients (56/271) with an incidence rate of 72/10,000 patient-days. Logistic regression analysis identified exposure to cephalosporin as an independent risk factor associated with rCDI (RR: 1.7; 95% CI: 1.1-2.7, p = 0.03).

CONCLUSION

Our study confirms the relevance of rCDI in terms of morbidity and mortality and provides a reliable estimation of its incidence.

Fecal Microbiota Transplantation (FMT) with Colonoscopy Is Superior to Enema and Nasogastric Tube While Comparable to Capsule for the Treatment of Recurrent Clostridioides difficile Infection: A Systematic Review and Meta-Analysis

BACKGROUND

Several routes of fecal microbiota transplantation (FMT) administration are available for treating recurrent Clostridioides difficile infections (CDI), the most recent of which are capsules.

AIM

To assess the efficacy of colonoscopy, capsule, enema, and nasogastric tube (NGT) FMT for the treatment of recurrent CDI.

METHODS

We reported clinical outcomes of colonoscopy, capsule, enema, and NGT FMT for the treatment of recurrent CDI according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. During January 2000 to January 2018, three databases were searched: PubMed, EMBASE, and CINAHL. Primary outcome was overall cure rate which was assessed using a random effects model; secondary outcomes included adverse effects as well as subgroup analyses comparing donor relationship, sample preparation, and study design.

RESULTS

Twenty-six studies (1309 patients) were included in the study. FMT was administered using colonoscopy in 16 studies (483 patients), NGT in five studies (149 patients), enema in four studies (360 patients), and capsules in four studies (301 patients). The random effects of pooled FMT cure rates were colonoscopy 94.8% (CI 92.4-96.8%; I2 15.6%), capsule 92.1% (CI 88.6-95.0%; I2 7.1%), enema 87.2% (CI 83.4-90.5%; I2 0%), and NGT/NDT 78.1% (CI 71.6-84.1%; I2 0%). On subgroup analysis of colonoscopy FMT, sample preparation methods had comparable cure rates: fresh 94.9% compared to 94.5%. Similarly, cure rates were unaffected by donor relationship: mixed 94.5% compared to unrelated donor 95.7%.

CONCLUSION

CDI cure rates with FMT performed with colonoscopy are superior to enema and NGT FMT, while those with FMT with colonoscopy and capsule are comparable.

The Acid-Dependent and Independent Effects of Lactobacillus acidophilus CL1285, Lacticaseibacillus casei LBC80R, and Lacticaseibacillus rhamnosus CLR2 on Clostridioides difficile R20291

Clostridioides difficile infections (CDI) result from antibiotic use and cause severe diarrhea which is life threatening and costly. A specific probiotic containing Lactobacillus acidophilus CL1285, Lacticaseibacillus casei LBC80R, and Lacticaseibacillus rhamnosus CLR2 has demonstrated a strong inhibitory effect on the growth of several nosocomial C. difficile strains by production of antimicrobial metabolites during fermentation. Though there are several lactobacilli shown to inhibit C. difficile growth by processes relying on acidification, this probiotic has demonstrated potency for CDI prevention among hospitalized patients. Here, we describe the acid-dependent and independent mechanisms by which these strains impair the cytotoxicity of a hypervirulent strain, C. difficile R20291 (CD). These bacteria were co-cultured in a series of experiments under anaerobic conditions in glucose-rich and no-sugar medium to inhibit or stimulate CD toxin production, respectively. In glucose-rich medium, there was low CD toxin production, but sufficient amounts to cause cytotoxic damage to human fibroblast cells. In co-culture, there was acidification by the lactobacilli resulting in growth inhibition as well as ≥ 99% reduced toxin A and B production and no observable cytotoxicity. In the absence of glucose, CD produced much more toxin. In co-culture, the lactobacilli did not acidify the medium and CD growth was unaffected; yet, the amount of detected toxin A and B was decreased by 20% and 41%, respectively. Despite the high concentration of toxin, cells exposed to the supernatant from the co-culture were able to survive. These results suggest that in addition to known acid-dependent effects, the combination of L. acidophilus CL1285, L. casei LBC80R, and L. rhamnosus CLR2 can interfere with CD pathogenesis without acidification: (1) reduced toxin A and B production and (2) toxin neutralization. This might explain the strain specificity of this probiotic in potently preventing C. difficile-associated diarrhea in antibiotic-treated patients compared with other probiotic formulae.

External validation of two prediction tools for patients at risk for recurrent Clostridioides difficile infection

BACKGROUND

One in four patients with primary Clostridioides difficile infection (CDI) develops recurrent CDI (rCDI). With every recurrence, the chance of a subsequent CDI episode increases. Early identification of patients at risk for rCDI might help doctors to guide treatment. The aim of this study was to externally validate published clinical prediction tools for rCDI.

METHODS

The validation cohort consisted of 129 patients, diagnosed with CDI between 2018 and 2020. rCDI risk scores were calculated for each individual patient in the validation cohort using the scoring tools described in the derivation studies. Per score value, we compared the average predicted risk of rCDI with the observed number of rCDI cases. Discrimination was assessed by calculating the area under the receiver operating characteristic curve (AUC).

RESULTS

Two prediction tools were selected for validation (Cobo 2018 and Larrainzar-Coghen 2016). The two derivation studies used different definitions for rCDI. Using Cobo's definition, rCDI occurred in 34 patients (26%) of the validation cohort: using the definition of Larrainzar-Coghen, we observed 19 recurrences (15%). The performance of both prediction tools was poor when applied to our validation cohort. The estimated AUC was 0.43 [95% confidence interval (CI); 0.32-0.54] for Cobo's tool and 0.42 (95% CI; 0.28-0.56) for Larrainzar-Coghen's tool.

CONCLUSION

Performance of both prediction tools was disappointing in the external validation cohort. Currently identified clinical risk factors may not be sufficient for accurate prediction of rCDI.

Faecal transplantation and Clostridioides difficile infection

Faecal microbiota transplantation (FMT), known equally well as faecal transplantation or faecal bacteriotherapy, is the process of implanting the faecal suspension containing balanced microbiota from a healthy donor to the colon of a recipient patient. Excessive growth of Clostridioides difficile (C difficile) in the intestinal microbiota resulting from antibiotic consumption is currently a rising threat to public health. FMT is one of the most important, newer approaches to treating C difficile infections. Since C difficile is regarded as an opportunistic bacterium triggering disease in conditions of disturbed homeostasis of the intestinal microbiota, restoration of healthy intestinal microflora facilitates suppression of toxic strain of C difficile by anaerobic bacteria of normal intestinal microflora with concomitant cure. Nurses have important role in caring for patients after faecal transplantation.

Real-World Experience with Bezlotoxumab for Prevention of Recurrence of Clostridioides difficile Infection

Bezlotoxumab is marketed for the prevention of recurrent Clostridioides difficile infection (rCDI). Its high cost could be determining its prescription to a different population than that represented in clinical trials. The objective of the study was to verify the effectiveness and safety of bezlotoxumab in preventing rCDI and to investigate factors related to bezlotoxumab failure in the real world. A retrospective, multicentre cohort study of patients treated with bezlotoxumab in Spain was conducted. We compared the characteristics of cohort patients with those of patients treated with bezlotoxumab in the pivotal MODIFY trials. We assessed recurrence rates 12 weeks after completion of treatment against C. difficile, and we analysed the factors associated with bezlotoxumab failure. Ninety-one patients were included in the study. The cohort presented with more risk factors for rCDI than the patients included in the MODIFY trials. Thirteen (14.2%) developed rCDI at 12 weeks of follow-up, and rCDI rates were numerically higher in patients with two or more previous episodes (25%) than in those who had fewer than two previous episodes of C. difficile infection (CDI) (10.4%); p = 0.09. There were no adverse effects attributable to bezlotoxumab. Despite being used in a more compromised population than that represented in clinical trials, we confirm the effectiveness of bezlotoxumab for the prevention of rCDI.

Faecal microbiota transplantation for recurrent Clostridioides difficile infection: An updated systematic review and meta-analysis

BACKGROUND

Faecal microbiota transplantation (FMT) is effective for recurrent Clostridioides difficile infection (CDI), but inconsistent effect rates and uncertain evidence levels have warranted caution. To clarify, we aimed to establish the evidence of FMT for recurrent CDI, updated across different delivery methods, treatment regimens, and in comparison with standard antibiotics.

METHODS

In this updated systematic review and meta-analysis, we searched PubMed, Scopus, Embase, Web of Science, Clinical Key, and Svemed+ for FMT literature published in English until November 11, 2019. We included observational and clinical trials with or without antibiotic comparators and excluded studies with below 8 weeks follow-up and fewer than 15 patients. The primary outcome was clinical outcome by week 8. We comprehensively extracted patient and procedural data. In a random-effects meta-analysis, we estimated the clinical effect for repeat or single FMT, different delivery methods, and versus antibiotics. We rated the evidence according to the Cochrane and GRADE methods. The PROSPERO preregistration number is CRD42020158112.

FINDINGS

Of 1816 studies assessed, 45 studies were included. The overall clinical effect week 8 following repeat FMT (24 studies, 1855 patients) was 91% (95% CI: 89-94%, I 2=53%) and 84% (80-88%, I 2=86%) following single FMT (43 studies, 2937 patients). Delivery by lower gastrointestinal endoscopy was superior to all other delivery methods, and repeat FMT significantly increased the treatment effect week 8 (P<0·001). Compared with vancomycin, the number needed to treat (NNT) for repeat FMT was 1·5 (1·3-1·9, P<0·001) and 2.9 (1·5-37·1, P=0·03) for single FMT. Repeat FMT had high quality of evidence.

INTERPRETATION

High-quality evidence supports FMT is effective for recurrent CDI, but its effect varies with the delivery method and the number of administrations. The superior NNT for FMT compared with antibiotics suggests that patients may benefit from advancing FMT to all instances of recurrent CDI.

FUNDING

Innovation Fund Denmark (j.no. 8056-00006B).

Recent advances in the treatment of Clostridioides difficile infection: the ever-changing guidelines

Clostridioides difficile infection (CDI), formerly known as Clostridium difficile, continues to be the most common healthcare-associated infection worldwide. With the shifting epidemiology towards higher a incidence of community-acquired CDI and the continued burden on the healthcare system posed by high rates of CDI recurrence, there has been an impetus to advance the diagnostic testing and treatment strategies. Recent advancements over the past decade have led to rapidly changing guidelines issued by the Infectious Diseases Society of America and European Society of Clinical Microbiology and Infectious Diseases. With our comprehensive review, we aim to summarize the latest advances in diagnosing and treating CDI and thus attempt to help readers guide best practices for patient care. This article also focusses on cost-effectiveness of various therapies currently available on the market and provides an analysis of the current evidence on a relatively new monoclonal antibody therapy, Bezlotoxumab, to treat recurrent CDI.

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

BACKGROUND

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

AIM

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

METHODS

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

FINDINGS

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

CONCLUSIONS

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

Human C. difficile toxin-specific memory B cell repertoires encode poorly neutralizing antibodies

Clostridioides difficile is a leading cause of nosocomial infection responsible for significant morbidity and mortality with limited options for therapy. Secreted C. difficile toxin B (TcdB) is a major contributor to disease pathology, and select TcdB-specific Abs may protect against disease recurrence. However, the high frequency of recurrence suggests that the memory B cell response, essential for new Ab production following C. difficile reexposure, is insufficient. We therefore isolated TcdB-specific memory B cells from individuals with a history of C. difficile infection and performed single-cell deep sequencing of their Ab genes. Herein, we report that TcdB-specific memory B cell-encoded antibodies showed somatic hypermutation but displayed limited isotype class switch. Memory B cell-encoded mAb generated from the gene sequences revealed low to moderate affinity for TcdB and a limited ability to neutralize TcdB. These findings indicate that memory B cells are an important factor in C. difficile disease recurrence.

Fidaxomicin for the treatment of Clostridioides difficile in children

Fidaxomicin is an oral narrow-spectrum novel 18-membered macrocyclic antibiotic that was initially approved in 2011 by the US FDA for the treatment of Clostridioides difficile infections (CDI) in adults. In February 2020, the FDA approved fidaxomicin for the treatment of CDI in children age >6 months. In adults, fidaxomicin is as efficacious as vancomycin in treating CDI and reduces the risk of recurrent CDI. An investigator-blinded, randomized, multicenter, multinational clinical trial comparing the efficacy and safety of fidaxomicin with vancomycin in children was recently published confirming similar findings as previously reported in adults. Fidaxomicin is the first FDA-approved treatment for CDI in children and offers a promising option for reducing recurrent CDI in this population.

Economic evaluation of Faecal microbiota transplantation compared to antibiotics for the treatment of recurrent Clostridioides difficile infection

BACKGROUND

Clostridioides difficile infection (CDI) is a hospital acquired disease associated with significant morbidity, hospitalisation and mortality. Almost 30% of treated patients experience at least one recurrence after treatment of their first episode. Treatment of recurrent CDI (rCDI) utilises vancomycin or fidaxomicin, however, a newer treatment option is faecal microbial transplantation (FMT) administered by nasogastric tube (NGT) or colonoscopy. It is associated with higher cure and lower recurrence rates than fidaxomicin or vancomycin. The aim of this analysis is to evaluate the cost effectiveness of FMT for rCDI using the latest and best evidence.

METHOD

A cost utility analysis was conducted using a decision model representing the cost per additional Quality Adjusted Life Year (QALY) from a National Health Service (NHS) perspective. A Markov model was constructed to compare FMT NGT and colonoscopy to antibiotic treatment (fidaxomicin or vancomycin). The model was informed by a literature review of clinical evidence, specifically focussing on hospitalised patients with rCDI over 65 years. Both deterministic and probabilistic sensitivity analyses were performed to assess uncertainties around the model inputs and assumptions.

FINDINGS

The base case analysis showed that FMT is a less costly and more effective treatment than either fidaxomicin or vancomycin. FMT colonoscopy was slightly more effective than FMT NGT leading to an additional 0.012 QALYs but more expensive and the incremental cost effectiveness ratio (ICER) was £242,514/QALY. The Probabilistic sensitivity analysis based on 10,000 simulations suggested the probability of FMT NGT being cost effective was almost 78% at £20,000/QALY Willingness-To-Pay (WTP) threshold.

INTERPRETATION

FMT is both more effective and less costly option than antimicrobial therapy. FMT NGT was the preferred route of administration and is likely to be considered the most cost-effective strategy by decision makers given current acceptable thresholds.

Effect of a prospective audit with intervention and feedback on Clostridioides difficile infection management

Background Clostridioides difficile infections are associated with morbidity and mortality in several countries. Their increasing incidence and frequent recurrence make them an urgent public health threat. The lack of adherence to international treatment guidelines for Clostridioides difficile infections is a proven mortality risk factor. Objective To evaluate long-term prescribers' adherence to recommendations on the management of Clostridioides difficile infections and its impact on clinical outcomes after an educational and Clostridioides difficile-prospective audit with intervention and feedback period. Setting All patients admitted to a 1500-bed university hospital with positive Clostridioides difficile tests identified were included. Methods Data were collected retrospectively over a baseline period (May-November 2014) and prospectively over a Clostridioides difficile-prospective audit with intervention and feedback period (November 2015-May 2016) and an observation period (November 2017-September 2018). All Clostridioides difficile cases were reviewed by a Clostridioides difficile-prospective audit with intervention and feedback team composed of pharmacists, an infectious diseases specialist and a microbiologist to obtain a complete overview of patient records in each area of expertise. Main outcome measures Percentage of conformity to the protocol, percentage of recovery at 10 days and percentage of relapse, as well as Clostridioides difficile incidence and percentage of Fidaxomicin use. Results A total of 183 patients were included over the three periods. A significant improvement in conformity to the local protocol was observed between the intervention period (23.9%) and the observation period (67.3%) (P < 10^-3). Fidaxomicin prescriptions increased significantly (P = 0.006). Clinical outcomes improved significantly with an increase in the percentage of recovery at 10 days (P = 0.001) and a decrease in the percentage of relapse (P = 0.016). The Clostridioides difficile incidence rate improved significantly to 1.3 per 10,000 patient-days during the observation period. Conclusion This study shows the lasting effect of an educational and Clostridioides difficile-prospective audit with intervention and feedback period on prescribers' adherence to recommendations and a significant impact on clinical outcomes.

Incidence, outcome, and risk factors for recurrence of nosocomial Clostridioides difficile infection in adults: A prospective cohort study

BACKGROUND

Nosocomial Clostridioides difficile infection (CDI) complicates up to 1% of all hospital admissions and is associated with considerable health burden.

AIMS

To determine the incidence and outcomes of nosocomial CDI at a major University Medical Center.

METHODS

Consecutive adult nosocomial CDI cases were prospectively identified. Stool samples were collected for ribotyping and antibiotic resistance testing. Patients were followed for eight weeks after discharge for relapse.

RESULTS

Over a 2-year period, 215 patients developed nosocomial CDI (incidence 2:1000) and 200 (mean age 62.2±19.6 years) gave informed consent. Mean hospital stay was 23.3±28.9 days (range 0-278). Infection was diagnosed within 7 days of admission (range 0-95) in 129 patients (64.5%). More than two-thirds (69.0%) were previously hospitalized within 12 weeks of the index hospitalization. Twenty five percent received prior antibiotics within eight weeks. Fifty-two patients (26.0%) did not receive antibiotics prior to diagnosis. Considerable comorbidities (Charlson Comorbidity Index ≥8) were noted in 33.5% of patients. Recurrence occurred in 43 patients (21.5%). On multivariate logistic regression, fluoroquinolone exposure was the only predictor of recurrence (OR=2.9, 95%CI 1.1-7.7). Overall mortality was 14.0% and CCI ≥8 was the only predictor on multivariate analysis (p=0.004). Genotyping did not identify any known hypervirulent strains and all isolates were susceptible to metronidazole and vancomycin.

CONCLUSION

Antibiotic exposure, comorbidities, and prior hospitalization constitute the major risk factors for nosocomial CDI. Recurrence is common and is associated with fluoroquinolones exposure. High baseline comorbidity score was the only predictor of increased mortality in this prospective cohort.

Recurrence of Clostridium difficile infection in the Western Australian population

Clostridium difficile, the most common cause of hospital-associated diarrhoea in developed countries, presents major public health challenges. The high clinical and economic burden from C. difficile infection (CDI) relates to the high frequency of recurrent infections caused by either the same or different strains of C. difficile. An interval of 8 weeks after index infection is commonly used to classify recurrent CDI episodes. We assessed strains of C. difficile in a sample of patients with recurrent CDI in Western Australia from October 2011 to July 2017. The performance of different intervals between initial and subsequent episodes of CDI was investigated. Of 4612 patients with CDI, 1471 (32%) were identified with recurrence. PCR ribotyping data were available for initial and recurrent episodes for 551 patients. Relapse (recurrence with same ribotype (RT) as index episode) was found in 350 (64%) patients and reinfection (recurrence with new RT) in 201 (36%) patients. Our analysis indicates that 8- and 20-week intervals failed to adequately distinguish reinfection from relapse. In addition, living in a non-metropolitan area modified the effect of age on the risk of relapse. Where molecular epidemiological data are not available, we suggest that applying an 8-week interval to define recurrent CDI requires more consideration.

Excess length of hospital stay, mortality and cost attributable to Clostridioides (Clostridium) difficile infection and recurrence: a nationwide analysis in Japan

Clostridioides (Clostridium) difficile infection (CDI) is the leading cause of infectious diarrhoea in hospitalised patients, representing a substantial economic burden driven mainly by increased length of hospital stay (LoS). Currently in Japan, limited evidence on CDI-associated excess LoS is available. We conducted a retrospective, matched-cohort study using a large, Japanese, hospital-based administrative database. CDI was defined as CDI treatment plus either CDI diagnosis or positive enzyme immunoassay result. Propensity score matching at the time of CDI or recurrent CDI (rCDI) onset was applied to adjust baseline confounding and immortal time bias. The analysis included 5 994 054 hospitalisation records during 2008-2017, of which 11 823 were identified as CDI and 1359 as rCDI. The median excess LoS attributable to CDI and rCDI was 3 days and 6.5 days, respectively. The excess mortality attributable to CDI was 6.9%; there was no excess mortality attributable to rCDI (-1.9%). The median difference in costs attributable to CDI and rCDI during the residual stay was JPY 130 296 (USD 1185) and JPY 81 054 (USD 737) per hospitalisation, respectively. By adjusting the biases, the burden of CDI in Japan was evaluated. The findings could support decision making and resource allocation for CDI management in Japanese hospitals.

Phenotypic and Genotypic Characteristics of Clostridium difficile Isolates in Patients with Type 2 Diabetes in Iran

Purpose

This study aimed to investigate the phenotypic and genotypic characterization of Clostridium difficile isolates in type 2 diabetes patients with hospital-acquired diarrhea in four teaching hospitals in Isfahan, Iran.

Patients and Methods

A total of 104 hospitalized patients with type 2 diabetes and nosocomial diarrhea were included in the current study over a 2-year period (2015–2017). C. difficile isolates were characterized by conventional microbiological methods including the presence of toxin genes, antibiotic resistance testing and molecular methods including multilocus sequence typing (MLST) and random amplification of polymorphic DNA (RAPD).

Results

All 21 C. difficile isolates (20.2%) were detected from 104 studied patients. All isolates were susceptible to metronidazole and vancomycin. The antimicrobial resistance rates were distinctly higher for clindamycin and for moxifloxacin. Based on PCR amplification of tcdA and tcdB, 13 isolates (12.5%) carried both of these genes and were considered toxigenic. Thirteen toxigenic C. difficile strains were classified into two sequence types (STs), that is, ST54 and ST2 types. The RAPD-PCR amplification patterns of the detected toxigenic C. difficile revealed three distinct but related RAPD clusters. RAPD cluster 1 had the highest similarity with RAPD types 2 and 3.

Conclusion

A relatively high rate of CDI was observed in patients with type 2 diabetes and was associated with poorer health outcomes. These patients were exposed to multiple antibiotics and other therapeutic agents. We recommend close screening for the coexistence of CDI and type 2 diabetes in patients with diarrhea using a combination of conventional and molecular methods.

Treatment of Clostridioides (Clostridium) difficile infection

Clostridioides (formerly: Clostridium) difficile infection (CDI) is a major cause of diarrhoea for inpatients as well as outpatients. Usually, CDI is healthcare-associated but the number of community-acquired infections is increasing. CDI is generally associated with changes in the normal intestinal microbiota caused by administration of antibiotics. Elderly and immunocompromised patients are at greater risk for CDI and CDI recurrence. Recently, the treatment options of CDI have undergone major changes: current recommendations speak against using metronidazole for primary CDI, fidaxomicin and bezlotoxumab have been added to the treatment armamentarium and microbial replacement therapies have emerged. Several other therapies are undergoing clinical trials. In this article, we review current treatment guidelines, present the most recent data on the options to treat CDI and glance towards future developments.KEY MESSAGESThe cornerstones for the treatment of CDI are vancomycin and fidaxomicin. Metronidazole should be used only in mild-to-moderate disease in younger patients who have no or only few risk factors for recurrence.In recurrent CDI, bezlotoxumab infusion (a monoclonal antibody against C. difficile toxin B) may be considered as an adjunctive therapeutic strategy in addition to the standard care provided to patients with several risk factors for recurrence.Faecal microbiota transplantation (FMT) should be offered to patients with frequently recurring CDI.

Strategies to prevent adverse outcomes following Clostridioides difficile infection in the elderly

Introduction: Clostridioides difficile remains the most common cause of healthcare-associated infections in the US, and it disproportionately affects the elderly. Older patients are more susceptible and have a greater risk of adverse outcomes from C. difficile infection (CDI), despite advances in treatment and prevention.Areas covered: The epidemiology and pathogenesis of CDI, as well as risk factors in the aging host, will be reviewed. The importance of antimicrobial stewardship and infection prevention in order to avoid acquisition and transmission will be discussed, as well as strategies to prevent adverse outcomes and recurrent CDI, through optimization of CDI treatment s,election.Expert opinion: Appropriate CDI-prevention strategies to avoid adverse outcomes in this susceptible population involve antimicrobial stewardship and methods to prevent C. difficile transmission in healthcare settings. Management strategies to prevent adverse outcomes include initiation of supportive therapy and proper selection of CDI specific treatments. Many patients may also benefit from adjunctive therapies or additional procedures.

Pet Ownership Protects Against Recurrence of Clostridioides difficile Infection

Background

Clostridioides difficile infection (CDI) is the leading cause of antibiotic-associated and health care–associated diarrhea in humans. Recurrent CDI (R-CDI) occurs in ~20%–30% of patients with CDI and results in increased morbidity, mortality, and hospital costs. Genomic analyses have shown overlap of C. difficile isolates from animals and people, suggesting that a zoonotic reservoir may contribute to recurrence. The objective of this study was to determine whether pet ownership is a risk factor for recurrence of CDI.

Methods

We conducted a case–control study among patients with recurrent CDI (cases; n = 86) and patients with nonrecurrent CDI (controls; n = 146). Multivariable logistic regression modeling was used to determine the association between recurrence of CDI and pet ownership while accounting for patient-level risk factors.

Results

Pet ownership was not significantly associated with recurrence of CDI (odds ratio [OR], 1.02; 95% confidence interval [CI], 0.38–2.72; P = 0.965) among all patients (n = 232). However, among the subset of patients with community-associated or community-onset health care facility–acquired CDI (n = 127), increasing contact with pets was increasingly protective against recurrence: for every point increase in a pet contact score (out of 7 possible points), the odds of recurrence decreased by 14% (OR, 0.86; 95% CI, 0.74–1.00; P = 0.051).

Conclusions

Close interactions with pets appear protective against the recurrence of community-acquired CDI. A potential mechanism may involve beneficial contributions to the microbiota of pet owners afflicted with CDI, as has been observed for other conditions such as atopy, obesity, and food allergies. However, more research is needed to understand the interactions between pets, owners, and their microbiota.

Multiple-Ascending-Dose Phase 1 Clinical Study of the Safety, Tolerability, and Pharmacokinetics of CRS3123, a Narrow-Spectrum Agent with Minimal Disruption of Normal Gut Microbiota

CRS3123 is a novel small molecule that potently inhibits methionyl-tRNA synthetase of Clostridioides difficile, inhibiting C. difficile toxin production and spore formation. CRS3123 has been evaluated in a multiple-ascending-dose placebo-controlled phase 1 trial. Thirty healthy subjects, ages 18 to 45 years, were randomized into three cohorts of 10 subjects each, receiving either 200, 400, or 600 mg of CRS3123 (8 subjects per cohort) or placebo (2 subjects per cohort) by oral administration twice daily for 10 days. CRS3123 was generally safe and well tolerated, with no serious adverse events (SAEs) or severe treatment-emergent adverse events (TEAEs) reported. All subjects completed their assigned treatment and follow-up visits, and there were no trends in systemic, vital sign, or laboratory TEAEs. There were no QTcF interval changes or any clinically significant changes in other electrocardiogram (ECG) intervals or morphology. CRS3123 showed limited but detectable systemic uptake; although absorption increased with increasing dose, the increase was less than dose proportional. Importantly, the bulk of the oral dose was not absorbed, and fecal concentrations were substantially above the MIC90 value of 1 μg/ml at all dosages tested. Subjects receiving either of the two lower doses of CRS3123 exhibited minimal disruption of normal gut microbiota after 10 days of twice-daily dosing. CRS3123 was inactive against important commensal anaerobes, including Bacteroides, bifidobacteria, and commensal clostridia. Microbiome data showed favorable differentiation compared to other CDI therapeutics. These results support further development of CRS3123 as an oral agent for the treatment of CDI. (This study has been registered at Clinicaltrials.gov under identifier NCT02106338.).

Where Stool is a Drug: International Approaches to Regulating the use of Fecal Microbiota for Transplantation

Regulatory agencies vary widely in their classification of FMT, with significant impact on patient access. This article conducts a global survey of national regulations and collates existing FMT classification statuses, ultimately suggesting that the human cell and tissue product designation best fits FMT's characteristics and that definitional objectives to that classification may be overcome.

Incidence of Bloodstream Infections, Length of Hospital Stay, and Survival in Patients With Recurrent Clostridioides difficile Infection Treated With Fecal Microbiota Transplantation or Antibiotics: A Prospective Cohort Study

BACKGROUND

Clostridioides difficile infection (CDI) is a risk factor for bloodstream infection (BSI). Fecal microbiota transplantation (FMT) is more effective than antibiotics in treating recurrent CDI, but its efficacy in preventing CDI-related BSI is uncertain.

OBJECTIVE

To assess incidence of primary BSI in patients with recurrent CDI treated with FMT versus antibiotics.

DESIGN

Prospective cohort study. Patients treated with FMT and those treated with antibiotics were matched on propensity score.

SETTING

Single academic medical center.

PATIENTS

290 inpatients with recurrent CDI (57 patients per treatment in matched cohort).

INTERVENTION

FMT or antibiotics.

MEASUREMENTS

The primary outcome was primary BSI within 90 days. Secondary outcomes were length of hospitalization and overall survival (OS) at 90 days.

RESULTS

Of the 290 patients, 109 were treated with FMT and 181 received antibiotics. Five patients in the FMT group and 40 in the antibiotic group developed BSI. Because of differences in the patients treated with FMT versus antibiotics in many baseline characteristics, including number of recurrences and CDI severity, comparative analyses were limited to the matched cohort. Risk for BSI was 23 percentage points (95% CI, 10 to 35 percentage points) lower in the FMT group; the FMT group also had 14 fewer days of hospitalization (CI, 9 to 20 fewer days) and a 32-percentage point increase in OS (CI, 16 to 47 percentage points) compared with the antibiotic group.

LIMITATION

Nonrandomized study with potential for unmeasured or residual confounding; limited generalizability of the propensity score-matched cohort.

CONCLUSION

In a propensity score-matched cohort, patients with recurrent CDI treated with FMT were less likely to develop primary BSI.

PRIMARY FUNDING SOURCE

None.

Bezlotoxumab for Prevention of Recurrent Clostridium difficile Infection in Patients at Increased Risk for Recurrence

Background

Bezlotoxumab is a human monoclonal antibody against Clostridium difficile toxin B indicated to prevent C. difficile infection (CDI) recurrence (rCDI) in adults at high risk for rCDI. This post hoc analysis of pooled monocolonal antibodies for C.difficile therapy (MODIFY) I/II data assessed bezlotoxumab efficacy in participants with characteristics associated with increased risk for rCDI.

Methods

The analysis population was the modified intent-to-treat population who received bezlotoxumab or placebo (n = 1554) by risk factors for rCDI that were prespecified in the statistical analysis plan: age ≥65 years, history of CDI, compromised immunity, severe CDI, and ribotype 027/078/244. The proportion of participants with rCDI in 12 weeks, fecal microbiota transplant procedures, 30-day all cause and CDI-associated hospital readmissions, and mortality at 30 and 90 days after randomization were presented.

Results

The majority of enrolled participants (75.6%) had ≥1 risk factor; these participants were older and a higher proportion had comorbidities compared with participants with no risk factors. The proportion of placebo participants who experienced rCDI exceeded 30% for each risk factor compared with 20.9% among those without a risk factor, and the rCDI rate increased with the number of risk factors (1 risk factor: 31.3%; ≥3 risk factors: 46.1%). Bezlotoxumab reduced rCDI, fecal microbiota transplants, and CDI-associated 30-day readmissions in participants with risk factors for rCDI.

Conclusions

The risk factors prespecified in the MODIFY statistical analysis plan are appropriate to identify patients at high risk for rCDI. While participants with ≥3 risk factors had the greatest reduction of rCDI with bezlotoxumab, those with 1 or 2 risk factors may also benefit.

Clinical Trials Registration

NCT01241552 (MODIFY I) and NCT01513239 (MODIFY II).

Cost-effectiveness of Bezlotoxumab Compared With Placebo for the Prevention of Recurrent Clostridium difficile Infection

Background

Clostridium difficile infection (CDI) is the most commonly recognized cause of recurrent diarrhea. Bezlotoxumab, administered concurrently with antibiotics directed against C. difficile (standard of care [SoC]), has been shown to reduce the recurrence of CDI, compared with SoC alone. This study aimed to assess the cost-effectiveness of bezlotoxumab administered concurrently with SoC, compared with SoC alone, in subgroups of patients at risk of recurrence of CDI.

Methods

A computer-based Markov health state transition model was designed to track the natural history of patients infected with CDI. A cohort of patients entered the model with either a mild/moderate or severe CDI episode, and were treated with SoC antibiotics together with either bezlotoxumab or placebo. The cohort was followed over a lifetime horizon, and costs and utilities for the various health states were used to estimate incremental cost-effectiveness ratios (ICERs). Both deterministic and probabilistic sensitivity analyses were used to test the robustness of the results.

Results

The cost-effectiveness model showed that, compared with placebo, bezlotoxumab was associated with 0.12 quality-adjusted life-years (QALYs) gained and was cost-effective in preventing CDI recurrences in the entire trial population, with an ICER of $19824/QALY gained. Compared with placebo, bezlotoxumab was also cost-effective in the subgroups of patients aged ≥65 years (ICER of $15298/QALY), immunocompromised patients (ICER of $12597/QALY), and patients with severe CDI (ICER of $21430/QALY).

Conclusions

Model-based results demonstrated that bezlotoxumab was cost-effective in the prevention of recurrent CDI compared with placebo, among patients receiving SoC antibiotics for treatment of CDI.

Fidaxomicin compared with vancomycin and metronidazole for the treatment of Clostridioides (Clostridium) difficile infection: A network meta-analysis

We conducted a systematic review of the literature and network meta-analysis (NMA) to compare the relative effectiveness of antibiotic treatments for Clostridioides (Clostridium) difficile infection (CDI) including vancomycin (VCM), metronidazole (MTZ) and fidaxomicin (FDX). Eligible studies were randomised controlled trials (RCTs) including adults with any severity of CDI that was treated with VCM, MTZ or FDX. The NMA was performed using a Bayesian framework, using a fixed-effects model. The searches identified seven publications for inclusion, which provided five RCTs for VCM versus MTZ, and three RCTs for FDX versus VCM. The NMA showed that for clinical cure rate, there was no difference for FDX versus VCM, and there was a significant difference in favour of FDX versus MTZ (odds ratio [OR]: 1.77; 95% credible interval [CrI] 1.11, 2.83]). For recurrence rate, there was a significant difference in favour of FDX versus both VCM (OR: 0.50; 95% CrI: 0.37, 0.68) and MTZ (OR: 0.44; 95% CrI: 0.27, 0.72). For sustained cure (clinical cure without recurrence), there was a significant difference in favour of FDX versus VCM (OR: 1.61; 95% CrI: 1.27, 2.05) and MTZ (OR: 2.39; 95% CrI: 1.65, 3.47). These findings suggest that FDX and VCM are effective first-line treatments for mild or moderate CDI, whereas MTZ is not, and FDX may be more effective at preventing CDI recurrence than VCM.

Prevention of recurrent Clostridioides difficile infection: A systematic review of randomized controlled trials

Recurrent Clostridioides (formerly Clostridium) difficile infection (rCDI) is common, and patients who have had one recurrence are more likely to have multiple recurrences. Frequent recurrences have been associated with increased morbidity and mortality, high healthcare costs, and lower quality of life. In this review, we compare the efficacy of interventions designed to prevent rCDI. We performed a systematic review of the English literature, including randomized controlled trials (RCTs) that evaluated rCDI as an outcome. Studies were included irrespective of patient demographics, disease severity, type of intervention, comparator used, or time-point of outcome evaluation. We performed a comprehensive literature search with the assistance of a research librarian. Two reviewers independently extracted data and assessed risk of bias. Our search yielded 38 RCTs (8,102 participants). Nineteen RCTs (3,743 subjects) evaluated antibiotics, eight fecal microbiota transplantation (FMT) (582 subjects), three monoclonal antibodies (MAbs) (2,805 subjects), and eight probiotics, prebiotics, or non-antibiotic polymers (972 subjects). The antibiotic and FMT therapies that demonstrated efficacy in rCDI prevention included: fidaxomicin (when compared to a ten-day vancomycin course) and FMT administered by nasogastric tube (when compared to a fourteen-day vancomycin course and a fourteen-day vancomycin course plus bowel lavage). Actoxumab (MAb against C. difficile toxin A; CDA1) plus bezlotoxumab (MAb against C. difficile toxin B; CDB1) in combination or bezlotoxumab alone appeared to be more effective in preventing rCDI compared to actoxumab alone. Of the prebiotics, probiotics, and nonantibiotic polymers, oligofructose, Saccharomyces boulardii, and the nontoxigenic C. difficile strain M3 were the most efficacious for rCDI prevention. Thirty-eight RCTs (>8,000 participants) evaluating treatment modalities for CDI were examined for efficacy in prevention of rCDI. Several CDI-specific antibiotics, FMT modalities, monoclonal antibodies, and various prebiotics and probiotics demonstrated a reduction in risk of rCDI with the greatest risk reduction observed with FMT and monoclonal antibody therapy. It is notable that the comparators in these studies were very different from one another and the relative risk reduction of rCDI may not be directly comparable from one study to the next.

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.

Updates in the epidemiology and management of candidemia and Clostridioides difficile coinfection

Introduction: In recent years, more and more studies have focused on the association between candidemia and Clostridioides difficile infection (CDI), highlighting the risk of subsequent candidemia in patients with CDI. However, a more recent model focuses on the Candida-Clostridioides difficile coinfection as a clinical entity in which candidemia could occur before or after the CDI episode. Areas covered: In this review we analyzed the physiopathological mechanisms underlying the Candida-Clostridioides difficile coinfection, both in case of candidemia preceding and following the CDI. We highlighted that gut alterations occurring during a CDI play a crucial role in the risk of subsequent candidemia. Moreover, we identified areas of interest about the management of Candida-Clostridioides difficile coinfection and proposed answers to relevant clinical questions. Expert opinion: The evaluation of risk factors for candidemia in patients with CDI and the rational antibiotic use in patients with candidemia remain the most efficacious and cost-free instruments to optimally manage the Candida-Clostridioides difficile coinfection. However, further studies are required to cover some unmet needs, such as the development of rapid diagnostic methods of candidemia and the use of new available drugs with minimal effect on the microbiome biodiversity in patients with CDI at high risk of fungemia.

In Vitro Antimicrobial Activity and Probiotic Potential of Bifidobacterium and Lactobacillus against Species of Clostridium

Many Clostridium species are found as commensal members of the intestinal microbiota. However, imbalances of the microbiota may lead to certain infections caused by these microorganisms, mainly Clostridium butyricum, Clostridium difficile, and Clostridium perfringens. In many cases, infection recurrence can occur after antibiotics, indicating the need for novel therapeutic options that act on the pathogens and also restore the microbiota. Herein, the in vitro antimicrobial activity and probiotic potential of clinical and reference strains of Bifidobacterium and Lactobacillus were investigated against Clostridium species. Antimicrobial activity was evaluated by the agar spot test and inhibition of gas production. Then, the probiotic potential of selected strains was assessed by analyzing their coaggregation ability, adhesive properties to host cells and mucin, tolerance to acidic pH and bile salts, and antimicrobial susceptibility profiles. Lactobacillus plantarum ATCC 8014 was the most promising strain based on its inhibitory activity against Clostridium spp. Also, this strain met criteria to be considered a probiotic based on its coaggregation ability, adhesive properties, and tolerance to harsh pH and bile acid salt conditions. The results indicate that among the studied strains, L. plantarum ATCC 8014 presents probiotic potential for controlling infections induced by the studied Clostridium species and should be further evaluated in in vivo animal models.

Nonsteroidal Anti-inflammatory Drugs Alter the Microbiota and Exacerbate Clostridium difficile Colitis while Dysregulating the Inflammatory Response

Clostridium difficile infection (CDI) is a major public health threat worldwide. The use of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with enhanced susceptibility to and severity of CDI; however, the mechanisms driving this phenomenon have not been elucidated. NSAIDs alter prostaglandin (PG) metabolism by inhibiting cyclooxygenase (COX) enzymes. Here, we found that treatment with the NSAID indomethacin prior to infection altered the microbiota and dramatically increased mortality and the intestinal pathology associated with CDI in mice. We demonstrated that in C. difficile-infected animals, indomethacin treatment led to PG deregulation, an altered proinflammatory transcriptional and protein profile, and perturbed epithelial cell junctions. These effects were paralleled by increased recruitment of intestinal neutrophils and CD4⁺ cells and also by a perturbation of the gut microbiota. Together, these data implicate NSAIDs in the disruption of protective COX-mediated PG production during CDI, resulting in altered epithelial integrity and associated immune responses.IMPORTANCEClostridium difficile infection (CDI) is a spore-forming anaerobic bacterium and leading cause of antibiotic-associated colitis. Epidemiological data suggest that use of nonsteroidal anti-inflammatory drugs (NSAIDs) increases the risk for CDI in humans, a potentially important observation given the widespread use of NSAIDs. Prior studies in rodent models of CDI found that NSAID exposure following infection increases the severity of CDI, but mechanisms to explain this are lacking. Here we present new data from a mouse model of antibiotic-associated CDI suggesting that brief NSAID exposure prior to CDI increases the severity of the infectious colitis. These data shed new light on potential mechanisms linking NSAID use to worsened CDI, including drug-induced disturbances to the gut microbiome and colonic epithelial integrity. Studies were limited to a single NSAID (indomethacin), so future studies are needed to assess the generalizability of our findings and to establish a direct link to the human condition.

Hypoalbuminemia as predictor of recurrence of Clostridium difficile infection

Background

Novel drugs for Clostridium difficile (C. difficile) infections have been proven to reduce recurrent infections. Because of their high financial costs, identification of patients at high risk for recurrence is essential to provide optimal treatment. The ATLAS score’s ability to predict 90-day recurrence, disease complications and 1‑year all-cause mortality was evaluated.

Methods

144 consecutive symptomatic patients with positive stool test for C. difficile were enrolled. The ATLAS score (consisting of the variables age, temperature, leukocyte count, albumin, systemic antibiotics, serum creatinine) was calculated and patients were stratified into 4 subgroups according to their scores. A Cox regression model was used to estimate the extent to which ATLAS was associated with 90-day recurrence. Furthermore, the score was correlated with disease complications and one-year all-cause mortality.

Results

ATLAS was unable to predict 90-day recurrence (p = 0.064, HR 1.134 [0.993;1.295]), but performed well for disease complications (D = 0.382, p < 0.001, HR 1.547 [1.266;1.889]) and mortality (p < 0.001, HR 1.374 [1.194;1.583]). Serum albumin was the only parameter able to predict 90-day recurrence (p = 0.016, HR 0.958 [0.926;0.992]) and was also a predictor of disease complications (p < 0.001, HR 0.865[0.809;0.924]) and one-year all-cause mortality (p < 0.001, HR 0.923 [0.896;0.950]). A threshold of 33.1g/L (sensitivity = 56%, specificity = 80%, AUC 0.683) and 29.2g/L (sensitivity = 75%, specificity = 70%, AUC 0.763) of serum albumin could be identified to be predictive for 90-day recurrence and one-year all-cause mortality, respectively.

Conclusions

Serum albumin and ATLAS are predictors of disease complications and mortality, while only serum albumin is significantly associated with 90-day disease recurrence.

Fecal microbiota transplantation: donor relation, fresh or frozen, delivery methods, cost-effectiveness

Fecal microbiota transplantation (FMT) has evolved into a robust and efficient means for treating recurrent Clostridium difficile infection (CDI). Our narrative review looks at the donor selection, preparation, delivery techniques and cost-effectiveness of FMT. We searched electronic databases, including PubMed, MEDLINE, Google Scholar, and Cochrane Databases, for studies that compared the biological effects of donor selection, fresh or frozen fecal preparation, and various delivery techniques. We also evaluated the cost-effectiveness and manually searched references to identify additional relevant studies. Overall, there is a paucity of studies that directly compare outcomes associated with related and non-related stool donors. However, inferences from prior studies indicate that the success of FMT does not depend on the donor-patient relationship. Over time, the use of unrelated donors has increased because of the formation of stool banks and the need to save processing time and capital. However, longitudinal studies are needed to clarify the optimal freezing time before microbial function declines. Several FMT techniques have been developed, such as colonoscopy, enema, nasogastric or nasojejunal tubes, and capsules. The comparable and high efficacy of FMT capsules, combined with their convenience, safety and aesthetically tolerable mode of delivery, makes it an attractive option for many patients. Cost-effective models comparing these various approaches support the use of FMT via colonoscopy as being the best strategy for the treatment of recurrent CDI.

Novel therapies and preventative strategies for primary and recurrent Clostridium difficile infections

Clostridium difficile is the leading infectious cause of antibiotic-associated diarrhea and colitis. C. difficile infection (CDI) places a heavy burden on the healthcare system, with nearly half a million infections yearly and an approximate 20% recurrence risk after successful initial therapy. The high incidence has driven new research on improved prevention such as the emerging use of probiotics, intestinal microbiome manipulation during antibiotic therapies, vaccinations, and newer antibiotics that reduce the disruption of the intestinal microbiome. While the treatment of acute C. difficile is effective in most patients, it can be further optimized by adjuvant therapies that improve the initial treatment success and decrease the risk of subsequent recurrence. Finally, the high risk of recurrence has led to multiple emerging therapies that target toxin activity, recovery of the intestinal microbial community, and elimination of latent C. difficile in the intestine. In summary, CDIs illustrate the complex interaction among host physiology, microbial community, and pathogen that requires specific therapies to address each of the factors leading to primary infection and recurrence.

Cost-Effectiveness Analysis of Bezlotoxumab Added to Standard of Care Versus Standard of Care Alone for the Prevention of Recurrent Clostridium difficile Infection in High-Risk Patients in Spain

INTRODUCTION

Clostridium difficile infection (CDI) is the major cause of infectious nosocomial diarrhoea and is associated with considerable morbidity, mortality and economic impact. Bezlotoxumab administered in combination with standard of care (SoC) antibiotic therapy prevents recurrent CDI. This study assessed the cost-effectiveness of bezlotoxumab added to SoC, compared to SoC alone, to prevent the recurrence of CDI in high-risk patients from the Spanish National Health System perspective.

METHODS

A Markov model was used to simulate the natural history of CDI over a lifetime horizon in five populations of patients at high risk of CDI recurrence according to MODIFY trials: (1) ≥ 65 years old; (2) severe CDI; (3) immunocompromised; (4) ≥ 1 CDI episode in the previous 6 months; and (5) ≥ 65 years old and with ≥ 1 CDI episode in the previous 6 months. The incremental cost-effectiveness ratio (ICER) expressed as cost per quality-adjusted life-year (QALY) gained was calculated. Deterministic (DSA) and probabilistic sensitivity analyses (PSA) were performed.

RESULTS

In all patient populations (from 1 to 5), bezlotoxumab added to SoC reduced CDI recurrence compared to SoC alone by 26.4, 19.5, 21.2, 26.6 and 39.7%, respectively. The resulting ICERs for the respective subgroups were €12,724, €17,495, €9545, €7386, and €4378. The model parameters with highest impact on the ICER were recurrence rate (first), mortality, and utility values. The probability that bezlotoxumab was cost-effective at a willingness-to-pay threshold of €21,000/QALY was 85.5%, 54.1%, 86.0%, 94.5%, 99.6%, respectively.

CONCLUSION

The results suggest that bezlotoxumab added to SoC compared to SoC alone is a cost-effective treatment to prevent the recurrence of CDI in high-risk patients. The influence of changes in model parameters on DSA results was higher in patients  ≥ 65 years old, with severe CDI and immunocompromised. Additionally, PSA estimated that the probability of cost-effectiveness exceeded 85% in most subgroups.

FUNDING

Merck Sharp & Dohme Corp.

Clostridium difficile control measures: current and future methods for prevention

INTRODUCTION

Clostridium difficile is the most common cause of healthcare associated infection, and C. difficile infection (CDI) is associated with significant costs, morbidity, and mortality. One obstacle to preventing CDI is lack of high quality data on interventions to prevent CDI. This has led some to focus on areas, such as method of hand hygiene, unlikely to impact CDI incidence as much as others, such as contact precautions. In addition, existing strategies, although effective, do have limitations. Another challenge is the ability to rapidly, and accurately, diagnose CDI. Given these obstacles, new strategies to effectively prevent CDI are imperative to improve patient outcomes. Areas covered: Evidence of the interventions recommended by international scientific societies will be reviewed, as well as ongoing research on new strategies, such as screening for asymptomatic C. difficile carriage, microbiota sparing agents, bacteriocins and vaccines. Expert commentary: Current measures to prevent CDI are effective, but have significant limitations. Contact precautions and antimicrobial stewardship are likely the most effective of current prevention recommendations. Diagnostic assay utilization plays a role as well. New strategies to prevent CDI are needed, and, fortunately, several are being studied. Most likely a combination of approaches will be necessary to optimize CDI prevention.