The potential economic value of screening hospital admissions for Clostridium difficile

Impact of including productivity costs in economic analyses of vaccines for C. difficile infections and infant respiratory syncytial virus, in a UK setting

OBJECTIVES

It has been estimated that vaccines can accrue a relatively large part of their value from patient and carer productivity. Yet, productivity value is not commonly or consistently considered in health economic evaluations of vaccines in several high-income countries. To contribute to a better understanding of the potential impact of including productivity value on the expected cost-effectiveness of vaccination, we illustrate the extent to which the incremental costs would change with and without productivity value incorporated.

METHODS

For two vaccines currently under development, one against Cloistridioides difficile (C. difficile) infection and one against respiratory syncytial disease (RSV), we estimated their incremental costs with and without productivity value included and compared the results.

RESULTS

In this analysis, reflecting a UK context, a C. difficile vaccination programme would prevent £12.3 in productivity costs for every person vaccinated. An RSV vaccination programme would prevent £49 in productivity costs for every vaccinated person.

CONCLUSIONS

Considering productivity costs in future cost-effectiveness analyses of vaccines for C. difficile and RSV will contribute to better-informed reimbursement decisions from a societal perspective.

Screening for Asymptomatic Clostridioides difficile Carriage Among Hospitalized Patients: A Narrative Review

Clostridioides difficile infection (CDI) has become the most common healthcare-associated infection in the United States, with considerable morbidity, mortality, and healthcare costs. Assessing new preventive strategies is vital. We present a literature review of studies evaluating a strategy of screening and isolation of asymptomatic carriers in hospital settings. Asymptomatic detection of C. difficile is reported in ~ 10-20% of admitted patients. Risk factors for carriage include recent hospitalization, previous antibiotics, older age, lower functional capacity, immunosuppression, and others. Asymptomatic C. difficile carriers of toxigenic strains are at higher risk for progression to CDI. They are also shedders of C. difficile spores and may contribute to the persistence and transmission of this bacterium. Screening for asymptomatic carriers at hospital admission can theoretically reduce CDI by isolating carriers to reduce transmission, and implementing antibiotic stewardship measures targeting carriers to prevent progression to clinical illness. Several observational studies, summarized in this review, have reported implementing screening and isolation strategies, and found a reduction in CDI rates. Nevertheless, the data are still limited to a few observational studies, and this strategy is not commonly practiced. Studies supporting screening were performed in North America, coinciding with the period of dominance of the 027/BI/NAP1 strain. Additional studies evaluating screening, followed by infection control and antibiotic stewardship measures, are needed.

Molecular characterization and genotyping of isolates from cancer patients with Clostridioides difficile infection or asymptomatic colonization

Introduction. Cancer patients with Clostridioides difficile infection (CDI) are at a higher risk for adverse outcomes. In addition, a high prevalence of Clostridioides difficile asymptomatic colonization (CDAC) has been reported in this vulnerable population.Gap Statement. The molecular characteristics and potential role of CDAC in healthcare-related transmission in the cancer population have been poorly explored.Aim. We aimed to compare the molecular and genotypic characteristics of C. difficile isolates from cancer patients with CDAC and CDI.Method. We conducted a prospective cohort study of cancer patients with CDAC or CDI from a referral centre. Molecular characterization, typification and tcdC gene expression of isolates were performed.Results. The hospital-onset and community-onset healthcare facility-associated CDI rates were 4.5 cases/10 000 patient-days and 1.4 cases/1 000 admissions during the study period. Fifty-one C. difficile strains were isolated: 37 (72 %) and 14 (28 %) from patients with CDI or CDAC, respectively. All isolates from symptomatic patients were tcdA+/tcdB+, and four (10 %) were ctdA+/ctdB+. In the CDAC group, 10 (71 %) isolates were toxigenic, and none were ctdA+/ctdB+. The Δ18 in-frame tcdC deletion and two transition mutations were found in five isolates. After bacterial typing, 60 % of toxigenic isolates from asymptomatic carriers were clonal to those from patients with C. difficile-associated diarrhoea. No NAP1/027/BI strains were detected.Conclusions. We found a clonal association between C. difficile isolates from patients with CDAC and CDI. Studies are needed to evaluate the potential role of asymptomatic carriers in the dynamics of nosocomial transmission to support infection control measures and reduce the burden of CDI in high-risk groups.

Cost-Effectiveness Analysis of REBYOTA™ (Fecal Microbiota, Live-jslm [FMBL]) Versus Standard of Care for the Prevention of Recurrent Clostridioides difficile Infection in the USA

INTRODUCTION

Recurrent Clostridioides difficile infection (rCDI) is common and associated with considerable clinical and economic consequences. REBYOTA™ (fecal microbiota, live-jslm [FMBL]) is a microbiota-based live biotherapeutic approved for the prevention of rCDI following antibiotic treatment for rCDI. We sought to evaluate cost-effectiveness of FMBL compared to standard of care (SOC) from a US third-party payer perspective among patients with one or more (≥ 1) recurrences.

METHODS

A Markov model with a lifetime time horizon was developed. The model population included adult patients who had ≥ 1 recurrence after a primary CDI episode and had completed ≥ 1 round of antibiotics, or had ≥ 2 severe CDI episodes resulting in hospitalization within the last year. The model consisted of six health states with an 8-week model cycle: rCDI, absence of CDI after recurrence, colectomy, ileostomy, ileostomy reversal, and death. Drug costs and rCDI-related medical costs were estimated in 2022 US dollars and discounted at 3% annually. Deterministic sensitivity analyses were performed.

RESULTS

Compared to SOC, FMBL at $9000/course resulted in an incremental cost-effectiveness ratio (ICER) of $18,727 per quality-adjusted life year (QALY) gained. The incremental cost was $5336 (FMBL $79,236, SOC $73,900) and the incremental effectiveness was 0.285 QALYs (FMBL 10.346, SOC 10.061). The cumulative drug acquisition and administration costs for the FMBL and SOC arms were $24,245 and $16,876, while rCDI-related medical costs for FMBL and SOC were $54,991 and $57,024, respectively. The ICER in the subgroup of patients at first recurrence was $13,727 per QALY gained. FMBL remained cost-effective across all sensitivity analyses.

CONCLUSIONS

FMBL was found to be cost-effective compared to SOC for the prevention of rCDI with more benefits among patients at first recurrence, with an ICER far below the payer ICER threshold of $100,000. Patients treated with FMBL experienced higher total QALYs and reduced healthcare resource utilization, including reduced hospitalizations.

Clostridioides difficile Infection in Liver Cirrhosis: A Concise Review

Clostridium difficile is a Gram-positive bacillus with fecal-oral transmission and is currently one of the most common nosocomial infections worldwide, which was renamed Clostridioides difficile in 2016. Clostridioides difficile infection (CDI) is a prevalent infection in cirrhosis and negatively affects prognosis. This study aimed to provide a concise review with clinical practice implications. The prevalence of CDI in cirrhotic patients increases, while the associated mortality decreases. Multiple groups of risk factors increase the likelihood of CDI in patients with cirrhosis, such as antibiotic use, the severity of cirrhosis, some comorbidities, and demographic aspects. Treatment in the general population is currently described in the latest guidelines. In patients with cirrhosis, rifaximin and lactulose have been shown to reduce CDI risk due to their modulatory effects on the intestinal flora, although conflicting results exist. Fecal microbiota transplantation (FMT) as a treatment for the second or subsequent CDI recurrences has demonstrated a good safety and efficacy in cirrhosis and CDI. Future validation in more prospective studies is needed. Screening of asymptomatic patients appears to be discouraged for the prevention currently, with strict hand hygiene and cleaning of the ward and medical equipment surfaces being the cornerstone of minimizing transmission.

Impact of Clostridioides difficile infection on patient-reported quality of life

OBJECTIVE

We investigated the quality of life (QoL) of patients hospitalized with C. difficile infection (CDI).

DESIGN

Prospective survey study.

SETTING

US tertiary-care referral center, acute-care setting.

PARTICIPANTS

Adults hospitalized with a diagnosis of CDI, defined as ≥3 episodes of unformed stool in 24 hours and a positive laboratory test for C. difficile.

METHODS

We surveyed patients from July 2019 to March 2020 using the disease-specific Cdiff32 questionnaire and the generic PROMIS GH survey. We compared differences in Cdiff32 scores among demographic and clinical subgroups (including CDI severity, CDI recurrence, and various comorbidities) using 2-sample t tests. We compared PROMIS GH scores to the general population T score of 50 using 1-sample t tests. We performed multivariable linear regression to identify predictors of Cdiff32 scores.

RESULTS

In total, 100 inpatients (mean age, 58.6 ±17.1 years; 53.0% male; 87.0% white) diagnosed with CDI completed QoL surveys. PROMIS GH physical health summary scores (T = 37.3; P < .001) and mental health summary scores (T = 43.4; P < .001) were significantly lower than those of the general population. In bivariate analysis, recurrent CDI, severe CDI, and number of stools were associated with lower Cdiff32 scores. In multivariable linear regression, recurrent CDI, severe CDI, and each additional stool in the previous 24 hours were associated with significantly decreased Cdiff32 scores.

CONCLUSIONS

Patients hospitalized with CDI reported low scores on the Cdiff32 and PROMIS GH, demonstrating a negative impact of CDI on QoL in multiple health domains. The Cdiff32 questionnaire is particularly sensitive to QoL changes in patients with recurrent or severe disease.

Evaluation of the Cost-effectiveness of Infection Control Strategies to Reduce Hospital-Onset Clostridioides difficile Infection

Importance

Clostridioides difficile infection is the most common hospital-acquired infection in the United States, yet few studies have evaluated the cost-effectiveness of infection control initiatives targeting C difficile.

Objective

To compare the cost-effectiveness of 9 C difficile single intervention strategies and 8 multi-intervention bundles.

Design, Setting, and Participants

This economic evaluation was conducted in a simulated 200-bed tertiary, acute care, adult hospital. The study relied on clinical outcomes from a published agent-based simulation model of C difficile transmission. The model included 4 agent types (ie, patients, nurses, physicians, and visitors). Cost and utility estimates were derived from the literature.

Interventions

Daily sporicidal cleaning, terminal sporicidal cleaning, health care worker hand hygiene, patient hand hygiene, visitor hand hygiene, health care worker contact precautions, visitor contact precautions, C difficile screening at admission, and reduced intrahospital patient transfers.

Main Outcomes and Measures

Cost-effectiveness was evaluated from the hospital perspective and defined by 2 measures: cost per hospital-onset C difficile infection averted and cost per quality-adjusted life-year (QALY).

Results

In this agent-based model of a simulated 200-bed tertiary, acute care, adult hospital, 5 of 9 single intervention strategies were dominant, reducing cost, increasing QALYs, and averting hospital-onset C difficile infection compared with baseline standard hospital practices. They were daily cleaning (most cost-effective, saving $358 268 and 36.8 QALYs annually), health care worker hand hygiene, patient hand hygiene, terminal cleaning, and reducing intrahospital patient transfers. Screening at admission cost $1283/QALY, while health care worker contact precautions and visitor hand hygiene interventions cost $123 264/QALY and $5 730 987/QALY, respectively. Visitor contact precautions was dominated, with increased cost and decreased QALYs. Adding screening, health care worker hand hygiene, and patient hand hygiene sequentially to the daily cleaning intervention formed 2-pronged, 3-pronged, and 4-pronged multi-intervention bundles that cost an additional $29 616/QALY, $50 196/QALY, and $146 792/QALY, respectively.

Conclusions and Relevance

The findings of this study suggest that institutions should seek to streamline their infection control initiatives and prioritize a smaller number of highly cost-effective interventions. Daily sporicidal cleaning was among several cost-saving strategies that could be prioritized over minimally effective, costly strategies, such as visitor contact precautions.

Reduced Clostridioides difficile infection in a pragmatic stepped-wedge initiative using admission surveillance to detect colonization

Background

Clostridioides difficile Infection (CDI) is a persistent healthcare issue. In the US, CDI is the most common infectious cause of hospital-onset (HO) diarrhea.

Objective

Assess the impact of admission testing for toxigenic C. difficile colonization on the incidence of HO-CDI.

Design

Pragmatic stepped-wedge Infection Control initiative.

Setting

NorthShore University HealthSystem is a four-hospital system near Chicago, IL.

Patients

All patients admitted to the four hospitals during the initiative.

Interventions

From September 2017 through August 2018 we conducted a quality improvement program where admitted patients had a peri-rectal swab tested for toxigenic C. difficile. All colonized patients were placed into contact precautions.

Measurements

We tested admissions who: i) had been hospitalized within two months, ii) had a past C. difficile positive test, and/or iii) were in a long-term care facility within six months. We measured compliance with all other practices to reduce the incidence of HO-CDI.

Results

30% of admissions were tested and 8.3% were positive. In the year prior to the initiative (Period 1) there were 63,057 admitted patients when HO-CDI incidence was 5.96 cases/10,000 patient days. During the 12-month initiative (Period 2) there were 62,760 admissions and the HO-CDI incidence was 4.23 cases/10,000 patient days (p = 0.02). There were no other practice or antibiotic use changes. Continuing admission surveillance provided a HO-CDI incidence of 2.9 cases/10,000 patient days during the final 9 months of 2018 (p<0.0001 compared to Period 1), equaling <1 case/1,000 admissions.

Limitations

This was not a randomized controlled trial, and multiple prevention practices were in place at the time of the admission surveillance initiative.

Conclusion

Admission C. difficile surveillance testing is an important tool for preventing hospital-onset C. difficile infection.

Registration

This quality improvement initiative is registered at ClinicalTrials.gov. The unique registration identifier number is NCT04014608.

Environmental shedding of toxigenic Clostridioides difficile by asymptomatic carriers: A prospective observational study

OBJECTIVES

The aim was to compare the burden of environmental shedding of toxigenic Clostridioides difficile among asymptomatic carriers, C. difficile-infected (CDI) patients and non-carriers in an inpatient non-epidemic setting.

METHODS

C. difficile carriage was determined by positive toxin-B PCR from rectal swabs of asymptomatic patients. Active CDI was defined as a positive two-step enzyme immunoassay/polymerase chain reaction (EIA/PCR) test in patients with more than three unformed stools/24 hr. C. difficile environmental contamination was assessed by obtaining specimens from ten sites in the patients' rooms. Toxigenic strains were identified by PCR. We created a contamination scale to define the overall level of room contamination that ranged from clean to heavy contamination.

RESULTS

One hundred and seventeen rooms were screened: 70 rooms inhabited by C. difficile carriers, 30 rooms by active CDI patients and 17 rooms by non C. difficile -carriers (control). In the carrier rooms 29 (41%) had more than residual contamination, from which 17 (24%) were heavily contaminated. In the CDI rooms 12 (40%) had more than residual contamination from which three (10%) were heavily contaminated, while in the control rooms, one room (6%) had more than residual contamination and none were heavily contaminated. In a multivariate analysis, the contamination score of rooms inhabited by carriers did not differ from rooms of CDI patients, yet both were significantly more contaminated than those of non-carriers odd ratio 12.23 and 11.16 (95% confidence interval 1.5-99.96 p 0.0195, and 1.19-104.49 p 0.035), respectively.

DISCUSSION

Here we show that the rooms of C. difficile carriers are as contaminated as those of patients with active CDI and significantly more than those of non-carriers.

Validation of Active Surveillance Testing for Clostridium difficile Colonization Using the cobas Cdiff Test

Clostridium difficile infection (CDI) is not declining in the United States. Nucleic acid amplification tests (NAAT) are used as part of active surveillance testing programs to prevent health care-associated infection. The objective of this study was to validate the cobas Cdiff Test on the cobas 4800 System (cobas) within a four-hospital system using prospectively collected perirectal swabs from asymptomatic patients at admission and during monthly intensive care unit (ICU) screening in an infection control CDI reduction program. Performance of the cobas was compared to that of toxigenic culture. Each positive cobas sample and the next following negative patient swab were cultured. The study design gave 273 samples processed by both cobas (137 positive and 136 negative) and culture (one negative swab was not cultured). Discrepant analysis was performed using a second NAAT, the Xpert C. difficile Epi test (Xpert). This strategy was compared to a medical record review for antibiotic receipt that would inhibit growth of C. difficile in colonic stool. None of the cobas-negative samples were culture positive. The cobas positive predictive value was 75.2% (95% confidence interval [CI], 66.9% to 82%) and positive percent agreement was 100% (95% CI, 96.0% to 100%). Overall agreement between cobas and direct toxigenic culture was 87.6% (95% CI, 83.1% to 91%). For the cobas-positive/culture-negative (discrepant) samples, 7 Xpert-positive samples were from patients receiving inhibitory antimicrobials; only 4 of 23 Xpert-negative samples received these agents (P = 0.00006). Our results support use of the cobas as a reliable assay for an active surveillance testing program to detect asymptomatic carriers of toxigenic C. difficile.

Impaired Quality of Life, Work, and Activities Among Adults with Clostridium difficile Infection: A Multinational Survey

BACKGROUND

Evidence of humanistic detriments of Clostridium difficile infection (CDI) remains limited.

AIMS

To assess humanistic burden associated with CDI.

METHODS

Self-reported National Health and Wellness Survey data between 2013 and 2016 were analyzed for the USA, five European countries, China, and Brazil. Outcome measures included SF-36v2^® for health-related quality of life (HRQoL) and Work Productivity and Activity Impairment questionnaire. Respondents (≥ 18 years old) were classified as (1) currently treated doctor-diagnosed CDI (C-CDI), (2) doctor-diagnosed prior CDI (P-CDI), or (3) never experienced CDI (NO-CDI). Regression modeling assessed the association between CDI status and outcomes, adjusting for potential confounders.

RESULTS

Of 352,780 respondents, 299, 2111, and 350,370 met the criteria for C-CDI, P-CDI, and NO-CDI, respectively, with 45% of the total from the USA. C-CDI and P-CDI respondents were older, were less often employed and had more comorbidities than those with NO-CDI. After adjustment for covariates, C-CDI and P-CDI had significantly lower HRQoL relative to NO-CDI for mental (MCS 39, 43 vs. 46) and physical (PCS 39, 41 vs. 46) component summary scores, and health utility (SF-6D 0.58, 0.64 vs. 0.71) (all p < 0.05), meeting common thresholds for minimally important differences. Those with C-CDI and P-CDI reported missing more work (21, 16 vs. 8%), greater impairment while working (43, 34 vs. 22%), and more activity impairment (61, 49 vs. 34%) than those with NO-CDI (all p < 0.05), respectively.

CONCLUSIONS

CDI is associated with meaningfully worse HRQoL and greater impairment to work and activities compared with NO-CDI. The impairment directly attributable to CDI requires further evaluation.

Economic evaluation of fecal microbiota transplantation for the treatment of recurrent Clostridium difficile infection in Australia

BACKGROUND AND AIM

Clostridium difficile is the most common cause of hospital-acquired diarrhea in Australia. In 2013, a randomized controlled trial demonstrated the effectiveness of fecal microbiota transplantation (FMT) for the treatment of recurrent Clostridium difficile infection (CDI). The aim of this study is to evaluate the cost-effectiveness of fecal microbiota transplantation-via either nasoduodenal or colorectal delivery-compared with vancomycin for the treatment of recurrent CDI in Australia.

METHODS

A Markov model was developed to compare the cost-effectiveness of fecal microbiota transplantation compared with standard antibiotic therapy. A literature review of clinical evidence informed the structure of the model and the choice of parameter values. Clinical effectiveness was measured in terms of quality-adjusted life years. Uncertainty in the model was explored using probabilistic sensitivity analysis.

RESULTS

Both nasoduodenal and colorectal FMT resulted in improved quality of life and reduced cost compared with vancomycin. The incremental effectiveness of either FMT delivery compared with vancomycin was 1.2 (95% CI: 0.1, 2.3) quality-adjusted life years, or 1.4 (95% CI: 0.4, 2.4) life years saved. Treatment with vancomycin resulted in an increased cost of AU$4094 (95% CI: AU$26, AU$8161) compared with nasoduodenal delivery of FMT and AU$4045 (95% CI: -AU$33, AU$8124) compared with colorectal delivery. The mean difference in cost between colorectal and nasoduodenal FMT was not significant.

CONCLUSIONS

If FMT, rather than vancomycin, became standard care for recurrent CDI in Australia, the estimated national healthcare savings would be over AU$4000 per treated person, with a substantial increase in quality of life.

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

Background

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

Methods

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

Results

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

Conclusion

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

A Comparison of Current Guidelines of Five International Societies on Clostridium difficile Infection Management

Clostridium difficile infection (CDI) is increasingly recognized as an emerging healthcare problem of elevated importance. Prevention and treatment strategies are constantly evolving along with the apperance of new scientific evidence and novel treatment methods, which is well-reflected in the differences among consecutive international guidelines. In this article, we summarize and compare current guidelines of five international medical societies on CDI management, and discuss some of the controversial and currently unresolved aspects which should be addressed by future research.

Hospitalized Patients with Heart Failure and Common Bacterial Infections: A Nationwide Analysis of Concomitant Clostridium Difficile Infection Rates and In-Hospital Mortality

BACKGROUND

Patients with heart failure (HF) are frequently hospitalized with common bacterial infections. It is unknown whether they experience concomitant Clostridium difficile infection (CDI) more frequently than patients without HF, and whether CDI affects their mortality.

METHODS

We used 2012 National Inpatient Sample data to determine the rate of CDI and associated in-hospital mortality for hospitalized patients with comorbid HF and urinary tract infection (UTI), pneumonia (PNA), or sepsis. Univariate and multivariate analyses were performed. Weighted data are presented.

RESULTS

There were an estimated 5,851,582 patient hospitalizations with discharge diagnosis of UTI, PNA, or sepsis in 2012 in the United States. Of these, 23.4% had discharge diagnosis of HF. Patients with HF were on average older and had more comorbidities. CDI rates were higher in hospitalizations with discharge diagnosis of HF compared with those without HF (odds ratio 1.13, 95% confidence interval 1.10-1.16) after controlling for patient demographics and comorbidities and hospital characteristics. Among HF hospitalizations with UTI, PNA, or sepsis, those with concomitant CDI had a higher in-hospital mortality than those without concomitant CDI (odds ratio 1.81, 95% confidence interval 1.71-1.92) after controlling for the covariates outlined previously.

CONCLUSIONS

HF is associated with higher CDI rates among hospitalized patients with other common bacterial infections, even when adjusting for other known risk factors for CDI. Among these patients with comorbid HF, CDI is associated with markedly higher in-hospital mortality. These findings may suggest an opportunity to improve outcomes for hospitalized patients with HF and common bacterial infections, possibly through improved Clostridium difficile screening and prophylaxis protocols.

An Economic Analysis of Strategies to Control Clostridium Difficile Transmission and Infection Using an Agent-Based Simulation Model

Background

A number of strategies exist to reduce Clostridium difficile (C. difficile) transmission. We conducted an economic evaluation of “bundling” these strategies together.

Methods

We constructed an agent-based computer simulation of nosocomial C. difficile transmission and infection in a hospital setting. This model included the following components: interactions between patients and health care workers; room contamination via C. difficile shedding; C. difficile hand carriage and removal via hand hygiene; patient acquisition of C. difficile via contact with contaminated rooms or health care workers; and patient antimicrobial use. Six interventions were introduced alone and "bundled" together: (a) aggressive C. difficile testing; (b) empiric isolation and treatment of symptomatic patients; (c) improved adherence to hand hygiene and (d) contact precautions; (e) improved use of soap and water for hand hygiene; and (f) improved environmental cleaning. Our analysis compared these interventions using values representing 3 different scenarios: (1) base-case (BASE) values that reflect typical hospital practice, (2) intervention (INT) values that represent implementation of hospital-wide efforts to reduce C. diff transmission, and (3) optimal (OPT) values representing the highest expected results from strong adherence to the interventions. Cost parameters for each intervention were obtained from published literature. We performed our analyses assuming low, normal, and high C. difficile importation prevalence and transmissibility of C. difficile.

Results

INT levels of the “bundled” intervention were cost-effective at a willingness-to-pay threshold of $100,000/quality-adjusted life-year in all importation prevalence and transmissibility scenarios. OPT levels of intervention were cost-effective for normal and high importation prevalence and transmissibility scenarios. When analyzed separately, hand hygiene compliance, environmental decontamination, and empiric isolation and treatment were the interventions that had the greatest impact on both cost and effectiveness.

Conclusions

A combination of available interventions to prevent CDI is likely to be cost-effective but the cost-effectiveness varies for different levels of intensity of the interventions depending on epidemiological conditions such as C. difficile importation prevalence and transmissibility.

Cost-effectiveness analysis of fecal microbiota transplantation for recurrent Clostridium difficile infection

OBJECTIVE

Clostridium difficile infection (CDI) places a high burden on the US healthcare system. Recurrent CDI (RCDI) occurs frequently. Recently proposed guidelines from the American College of Gastroenterology (ACG) and the American Gastroenterology Association (AGA) include fecal microbiota transplantation (FMT) as a therapeutic option for RCDI. The purpose of this study was to estimate the cost-effectiveness of FMT compared with vancomycin for the treatment of RCDI in adults, specifically following guidelines proposed by the ACG and AGA.

DESIGN

We constructed a decision-analytic computer simulation using inputs from the published literature to compare the standard approach using tapered vancomycin to FMT for RCDI from the third-party payer perspective. Our effectiveness measure was quality-adjusted life years (QALYs). Because simulated patients were followed for 90 days, discounting was not necessary. One-way and probabilistic sensitivity analyses were performed.

RESULTS

Base-case analysis showed that FMT was less costly ($1,669 vs $3,788) and more effective (0.242 QALYs vs 0.235 QALYs) than vancomycin for RCDI. One-way sensitivity analyses showed that FMT was the dominant strategy (both less expensive and more effective) if cure rates for FMT and vancomycin were ≥70% and <91%, respectively, and if the cost of FMT was <$3,206. Probabilistic sensitivity analysis, varying all parameters simultaneously, showed that FMT was the dominant strategy over 10, 000 second-order Monte Carlo simulations.

CONCLUSIONS

Our results suggest that FMT may be a cost-saving intervention in managing RCDI. Implementation of FMT for RCDI may help decrease the economic burden to the healthcare system.

Clostridium difficile infection: guideline-based diagnosis and treatment

BACKGROUND

Clostridium difficile (C. difficile) is the pathogen that most commonly causes nosocomial and antibiotic-associated diarrheal disease. Optimized algorithms for diagnosis, treatment, and hygiene can help lower the incidence, morbidity, and mortality of C. difficile infection (CDI).

METHODS

This review is based on pertinent articles that were retrieved by a selective search in PubMed for recommendations on diagnosis and treatment(up to March 2014), with particular attention to the current epidemiological situation in Germany.

RESULTS

The incidence of CDI in Germany is 5 to 20 cases per 100,000 persons per year. In recent years, a steady increase in severe, reportable cases of CDI has been observed, and the highly virulent epidemic strain Ribotype 027 has spread across nearly the entire country. For therapeutic and hygiene management, it is important that the diagnosis be made as early as possible with a sensitive screening test, followed by a confirmatory test for the toxigenic infection. Special disinfection measures are needed because of the formation of spores. The treatment of CDI is evidence-based; depending on the severity of the infection, it is treated orally with metronidazole, or else with vancomycin or fidaxomicin. Fulminant infections and recurrences call for specifically adapted treatment modalities. Treatment with fecal bacteria (stool transplantation) is performed in gastroenterological centers that have experience with this form of treatment after multiple failures of drug treatment for recurrent infection. For critically ill patients, treatment is administered by an interdisciplinary team and consists of early surgical intervention in combination with drug treatment. A therapeutic algorithm developed on the basis of current guidelines and recommendations enables risk-adapted, individualized treatment.

CONCLUSION

The growing clinical and epidemiological significance of CDI compels a robust implementation of multimodal diagnostic, therapeutic, and hygienic standards. In the years to come, anti-toxin antibodies, toxoid vaccines, and focused bacterial therapy will be developed as new treatment strategies for CDI.

Cost-effectiveness analysis of treatment strategies for initial Clostridium difficile infection

Clostridium difficile infection (CDI) is costly. Current guidelines recommend metronidazole as first-line therapy and vancomycin as an alternative. Recurrence is common. Faecal microbiota transplantation (FMT) is an effective therapy for recurrent CDI (RCDI). This study explores the cost-effectiveness of FMT, vancomycin and metronidazole for initial CDI. We constructed a decision-analytic computer simulation using inputs from published literature to compare FMT with a 10-14-day course of oral metronidazole or vancomycin for initial CDI. Parameters included cure rates (baseline value (range)) for metronidazole (80% (65-85%)), vancomycin (90% (88-92%)) and FMT(91% (83-100%)). Direct costs of metronidazole, vancomycin and FMT, adjusted to 2011 dollars, were $57 ($43-72), $1347 ($1195-1499) and $1086 ($815-1358), respectively. Our effectiveness measure was quality-adjusted life years (QALYs). One-way and probabilistic sensitivity analyses were conducted from the third-party payer perspective. Analysis using baseline values showed that FMT($1669, 0.242 QALYs) dominated (i.e. was less costly and more effective) vancomycin ($1890, 0.241 QALYs). FMT was more costly and more effective than metronidazole ($1167, 0.238 QALYs), yielding an incremental cost-effectiveness ratio (ICER) of $124 964/QALY. One-way sensitivity analyses showed that metronidazole dominated both strategies if its probability of cure were >90%; FMT dominated if it cost <$584. In a probabilistic sensitivity analysis at a willingness-to-pay threshold of $100 000/QALY, metronidazole was favoured in 55% of model iterations; FMT was favoured in 38%. Metronidazole, as the first-line treatment for CDIs, is less costly. FMT and vancomycin are more effective. However, FMT is less likely to be economically favourable, and vancomycin is unlikely to be favourable as first-line therapy when compared with FMT.

Comparing the economic and health benefits of different approaches to diagnosing Clostridium difficile infection

Accurate diagnosis of Clostridium difficile infection (CDI) is essential to effectively managing patients and preventing transmission. Despite the availability of several diagnostic tests, the optimal strategy is debatable and their economic values are unknown. We modified our previously existing C. difficile simulation model to determine the economic value of different CDI diagnostic approaches from the hospital perspective. We evaluated four diagnostic methods for a patient suspected of having CDI: 1) toxin A/B enzyme immunoassay, 2) glutamate dehydrogenase (GDH) antigen/toxin AB combined in one test, 3) nucleic acid amplification test (NAAT), and 4) GDH antigen/toxin AB combination test with NAAT confirmation of indeterminate results. Sensitivity analysis varied the proportion of those tested with clinically significant diarrhoea, the probability of CDI, NAAT cost and CDI treatment delay resulting from a false-negative test, length of stay and diagnostic sensitivity and specificity. The GDH/toxin AB plus NAAT approach leads to the timeliest treatment with the fewest unnecessary treatments given, resulted in the best bed management and generated the lowest cost. The NAAT-alone approach also leads to timely treatment. The GDH/toxin AB diagnostic (without NAAT confirmation) approach resulted in a large number of delayed treatments, but results in the fewest secondary colonisations. Results were robust to the sensitivity analysis. Choosing the right diagnostic approach is a matter of cost and test accuracy. GDH/toxin AB plus NAAT diagnosis led to the timeliest treatment and was the least costly.

Point-of-Care Testing for Clostridium Difficile Infection: A Real-World Feasibility Study of a Rapid Molecular Test in Two Hospital Settings

Introduction

In the developed world, Clostridium difficile infection (CDI) is the most important cause of nosocomial infectious diarrhea. In addition to providing epidemiological data and helping to indicate that a local outbreak may be occurring, laboratory tests are used to augment clinical decisions on individual patients. Very rarely do diagnostic tests provide results at the point of decision making; in the intervening period between requesting investigations on a patient with suspected CDI and return of the laboratory result, decisions must be made regarding patient isolation and treatment.

Methods

A 22-month, real-world feasibility study was conducted in patients with clinically significant diarrhea, in a London Hospital between March 2011 and January 2013, in three older persons’ wards and two intensive care units (ICUs) to determine acceptability, ease of use, change in turnaround time and clinical utility of a rapid, polymerase chain reaction (PCR)-based point-of-care test (POCT) (Cepheid GeneXpert^®, Sunnyvale, California, USA) for diagnosis of Clostridium difficile. Nurses in the older persons’ ward and laboratory technicians in the ICU were trained to perform the test. Residual samples were sent to the centralized laboratory for parallel testing using a two-step algorithm.

Results

A total of 335 samples were tested using the POCT with a median turnaround time of 1.85 h compared with 18 h for the centralized laboratory test. Overall agreement with centralized laboratory testing was 98.1%. Discrepant samples were more frequent on elderly wards than ICU. Overall 20/335 (6%) processing errors were encountered and were highest in the first few months of the study. Significantly more processing errors occurred on the older persons’ wards 13/102 (12.7%) than on ICU 7/271 (2.6%). Older persons’ patients who had POCT were significantly less likely to have a test requested for bacterial stool culture (3.1% vs. 10.9% p = 0.044). This difference was not observed in the ICU patients. No other differences in ancillary test requesting, mortality or length of stay were observed.

Conclusions

The majority of users reported that the POCT was easy to perform and was an acceptable part of their job. POCT using this system is feasible and acceptable to nursing staff and technicians working within these two hospital-based settings.

Electronic supplementary material

The online version of this article (doi:10.1007/s40121-014-0038-6) contains supplementary material, which is available to authorized users.

Cost and Impact on Patient Length of Stay of Rapid Molecular Testing for Clostridium difficile

Introduction

A study was performed to assess the cost of a rapid molecular assay (PCR) for diagnosis of Clostridium difficile infection (CDI) and the impact of its routine use on patient length of stay (LOS) in comparison with cell culture cytotoxin neutralization assay (CCNA).

Methods

From March 2011 to September 2011, Xpert^®C. difficile (Cepheid, Sunnyvale, CA, USA) PCR was used on patients with suspicion of CDI in two acute care hospitals in Abertawe Bro Morgannwg University Health Board, Swansea, Wales, UK. Test results were used for patient management. LOS and time to reportable result were compared for negative and positive prospective patients tested by PCR and historic control patients tested by CCNA during March 2010 to September 2010. Tests were priced using micro-costing and a cost comparison analysis was undertaken.

Results

In total, 506 patients were included. Time to reportable result for PCR samples was 1.53 h compared to 46.54 h for CCNA negatives and 22.45 h for CCNA positives. Patients tested by CCNA stayed 4.88 days longer in hospital compared to PCR patients if they tested positive and 7.03 days if tests were negative. The mean reduction in LOS observed in our study has the potential to generate cost savings of up to £2,292.62 for every patient with suspected CDI, if samples were to be tested routinely with PCR instead of CCNA.

Conclusion

A rapid molecular test for C. difficile in an acute hospital setting produced quick results that led to a decrease in LOS compared to historic CCNA control patients. This could result in considerable savings through reduced excess inpatient days.

Electronic supplementary material

The online version of this article (doi:10.1007/s40121-014-0034-x) contains supplementary material, which is available to authorized users.

A review of the economics of treating Clostridium difficile infection

Clostridium difficile infection (CDI) is a costly result of antibiotic use, responsible for an estimated 14,000 deaths annually in the USA according to the Centers for Disease Control and Prevention. Annual costs attributable to CDI are in excess of $US 1 billion. This review summarizes appropriate utilization of prevention and treatment methods for CDI that have the potential to reduce the economic and humanistic costs of the disease. Some cost-effective strategies to prevent CDI include screening and isolation of hospital admissions based on C. difficile carriage to reduce transmission in the inpatient setting, and probiotics, which are potentially efficacious in preventing CDI in the appropriate patient population. The most extensively studied agents for treatment of CDI are metronidazole, vancomycin, and fidaxomicin. Most economic comparisons between metronidazole and vancomycin favor vancomycin, especially with the emergence of metronidazole-resistant C. difficile strains. Metronidazole can only be recommended for mild disease. Moderate to severe CDI should be treated with vancomycin, preferably the compounded oral solution, which provides the most cost-effective therapeutic option. Fidaxomicin offers a clinically effective and potentially cost-effective alternative for treating moderate CDI in patients who do not have the NAP1/BI/027 strain of C. difficile. Probiotics and fecal microbiota transplant have variable efficacy and the US FDA does not currently regulate the content; the potential economic advantages of these treatment modalities are currently unknown.

Effectiveness of screening hospital admissions to detect asymptomatic carriers of Clostridium difficile: a modeling evaluation

OBJECTIVE

Both asymptomatic and symptomatic Clostridium difficile carriers contribute to new colonizations and infections within a hospital, but current control strategies focus only on preventing transmission from symptomatic carriers. Our objective was to evaluate the potential effectiveness of methods targeting asymptomatic carriers to control C. difficile colonization and infection (CDI) rates in a hospital ward: screening patients at admission to detect asymptomatic C. difficile carriers and placing positive patients into contact precautions.

METHODS

We developed an agent-based transmission model for C. difficile that incorporates screening and contact precautions for asymptomatic carriers in a hospital ward. We simulated scenarios that vary according to screening test characteristics, colonization prevalence, and type of strain present at admission.

RESULTS

In our baseline scenario, on average, 42% of CDI cases were community-onset cases. Within the hospital-onset (HO) cases, approximately half were patients admitted as asymptomatic carriers who became symptomatic in the ward. On average, testing for asymptomatic carriers reduced the number of new colonizations and HO-CDI cases by 40%-50% and 10%-25%, respectively, compared with the baseline scenario. Test sensitivity, turnaround time, colonization prevalence at admission, and strain type had significant effects on testing efficacy.

CONCLUSIONS

Testing for asymptomatic carriers at admission may reduce both the number of new colonizations and HO-CDI cases. Additional reductions could be achieved by preventing disease in patients who are admitted as asymptomatic carriers and developed CDI during the hospital stay.

Control of Clostridium difficile infection in the hospital setting

Clostridium difficile infection (CDI) has emerged as a leading challenge in the control of healthcare-associated infection (HCAI). The epidemiology of CDI has changed dramatically, this is associated with emergence of 'hypervirulent' strains, particularly PCR ribotype 027. Despite the epidemic spread of these strains, there are recent reports of decreasing incidence from healthcare facilities where multi-facetted targeted control programs have been implemented. We consider these changes in epidemiology and reflect on the tools available to control CDI in the hospital setting. The precise repertoire of measures adopted and emphasis on different interventions will vary, not only between healthcare systems, but also within different institutions within the same healthcare system. Finally, we consider both the sustainability of reductions already achieved, and the potential to reduce CDI further. This takes account of newly emerging data on more recent changes in the epidemiology of CDI, and the potential of novel interventions to decrease the burden of disease.

A simulation-based assessment of strategies to control Clostridium difficile transmission and infection

Background

Clostridium difficile is one of the most common and important nosocomial pathogens, causing severe gastrointestinal disease in hospitalized patients. Although "bundled" interventions have been proposed and promoted, optimal control strategies remain unknown.

Methods

We designed an agent-based computer simulation of nosocomial C. difficile transmission and infection, which included components such as: patients and health care workers, and their interactions; room contamination via C. difficile shedding; C. difficile hand carriage and removal via hand hygiene; patient acquisition of C. difficile via contact with contaminated rooms or health care workers; and patient antimicrobial use. We then introduced six interventions, alone and "bundled" together: aggressive C. difficile testing; empiric isolation and treatment of symptomatic patients; improved adherence to hand hygiene and contact precautions; improved use of soap and water for hand hygiene; and improved environmental cleaning. All interventions were tested using values representing base-case, typical intervention, and optimal intervention scenarios.

Findings

In the base-case scenario, C. difficile infection rates ranged from 8–21 cases/10,000 patient-days, with a case detection fraction between 32%–50%. Implementing the "bundle" at typical intervention levels had a large impact on C. difficile acquisition and infection rates, although intensifying the intervention to optimal levels had much less additional impact. Most of the impact came from improved hand hygiene and empiric isolation and treatment of suspected C. difficile cases.

Conclusion

A "bundled" intervention is likely to reduce nosocomial C. difficile infection rates, even under typical implementation conditions. Real-world implementation of the "bundle" should focus on those components of the intervention that are likely to produce the greatest impact on C. difficile infection rates, such as hand hygiene and empiric isolation and treatment of suspected cases.

Asymptomatic Clostridium difficile colonisation and onward transmission

Introduction

Combined genotyping/whole genome sequencing and epidemiological data suggest that in endemic settings only a minority of Clostridium difficile infection, CDI, is acquired from other cases. Asymptomatic patients are a potential source for many unexplained cases.

Methods

We prospectively screened a cohort of medical inpatients in a UK teaching hospital for asymptomatic C. difficile carriage using stool culture. Electronic and questionnaire data were used to determine risk factors for asymptomatic carriage by logistic regression. Carriage isolates were compared with all hospital/community CDI cases from the same geographic region, from 12 months before the study to 3 months after, using whole genome sequencing and hospital admission data, assessing particularly for evidence of onward transmission from asymptomatic cases.

Results

Of 227 participants recruited, 132 provided ≥1 stool samples for testing. 18 participants were culture-positive for C. difficile, 14/132(11%) on their first sample. Independent risk factors for asymptomatic carriage were patient reported loose/frequent stool (but not meeting CDI criteria of ≥3 unformed stools in 24 hours), previous overnight hospital stay within 6 months, and steroid/immunosuppressant medication in the last 6 months (all p≤0.02). Surprisingly antibiotic exposure in the last 6 months was independently associated with decreased risk of carriage (p = 0.005). The same risk factors were identified excluding participants reporting frequent/loose stool. 13/18(72%) asymptomatically colonised patients carried toxigenic strains from common disease-causing lineages found in cases. Several plausible transmission events to asymptomatic carriers were identified, but in this relatively small study no clear evidence of onward transmission from an asymptomatic case was seen.

Conclusions

Transmission events from any one asymptomatic carrier are likely to be relatively rare, but as asymptomatic carriage is common, it may still be an important source of CDI, which could be quantified in larger studies. Risk factors established for asymptomatic carriage may help identify patients for inclusion in such studies.

Diverse sources of C. difficile infection identified on whole-genome sequencing

BACKGROUND

It has been thought that Clostridium difficile infection is transmitted predominantly within health care settings. However, endemic spread has hampered identification of precise sources of infection and the assessment of the efficacy of interventions.

METHODS

From September 2007 through March 2011, we performed whole-genome sequencing on isolates obtained from all symptomatic patients with C. difficile infection identified in health care settings or in the community in Oxfordshire, United Kingdom. We compared single-nucleotide variants (SNVs) between the isolates, using C. difficile evolution rates estimated on the basis of the first and last samples obtained from each of 145 patients, with 0 to 2 SNVs expected between transmitted isolates obtained less than 124 days apart, on the basis of a 95% prediction interval. We then identified plausible epidemiologic links among genetically related cases from data on hospital admissions and community location.

RESULTS

Of 1250 C. difficile cases that were evaluated, 1223 (98%) were successfully sequenced. In a comparison of 957 samples obtained from April 2008 through March 2011 with those obtained from September 2007 onward, a total of 333 isolates (35%) had no more than 2 SNVs from at least 1 earlier case, and 428 isolates (45%) had more than 10 SNVs from all previous cases. Reductions in incidence over time were similar in the two groups, a finding that suggests an effect of interventions targeting the transition from exposure to disease. Of the 333 patients with no more than 2 SNVs (consistent with transmission), 126 patients (38%) had close hospital contact with another patient, and 120 patients (36%) had no hospital or community contact with another patient. Distinct subtypes of infection continued to be identified throughout the study, which suggests a considerable reservoir of C. difficile.

CONCLUSIONS

Over a 3-year period, 45% of C. difficile cases in Oxfordshire were genetically distinct from all previous cases. Genetically diverse sources, in addition to symptomatic patients, play a major part in C. difficile transmission. (Funded by the U.K. Clinical Research Collaboration Translational Infection Research Initiative and others.).

Is fidaxomicin worth the cost? An economic analysis

BACKGROUND

In May 2011, the Food and Drug Administration approved fidaxomicin for the treatment of Clostridium difficile infection (CDI). It has been found to be noninferior to vancomycin; however, its cost-effectiveness for the treatment of CDI remains undetermined.

METHODS

We developed a decision analytic simulation model to determine the economic value of fidaxomicin for CDI treatment from the third-party payer perspective. We looked at CDI treatment in these 3 cases: (1) no fidaxomicin, (2) only fidaxomicin, and (3) fidaxomicin based on strain typing results.

RESULTS

The incremental cost-effectiveness ratio for fidaxomicin based on screening given current conditions was >$43.7 million per quality-adjusted life-year and using only fidaxomicin was dominated (ie, more costly and less effective) by the other 2 treatment strategies explored. The fidaxomicin strategy tended to remain dominated, even at lower costs. With approximately 50% of CDI due to the NAP1/BI/027 strain, a course of fidaxomicin would need to cost ≤$150 to be cost-effective in the treatment of all CDI cases and between $160 and $400 to be cost-effective for those with a non-NAP1/BI/027 strain (ie, treatment based on strain typing).

CONCLUSIONS

Given the current cost and NAP1/BI/027 accounting for approximately 50% of isolates, using fidaxomicin as a first-line treatment for CDI is not cost-effective. However, typing and treatment with fidaxomicin based on strain may be more promising depending on the costs of fidaxomicin.