Predictors of first recurrence of Clostridium difficile infection: implications for initial management

Recurrent Clostridium difficile Infection in Children: Patient Risk Factors and Markers of Intestinal Inflammation

BACKGROUND

The management of Clostridium difficile infection (CDI) in children is complicated by recurrence rates of 20%-30%. The identification of risk factors associated with recurrent disease might allow early recognition of those children at highest risk.

METHODS

Pediatric patients with CDI were identified through clinical laboratory records at 2 tertiary-care children's hospitals from March 2013 through May 2014. Subjects were enrolled and followed for 60 days to assess for recurrent CDI (rCDI). Blood samples were obtained at enrollment to evaluate host interleukin (IL)-8 polymorphisms and anti-toxin A antibody levels; stool samples were obtained for inflammatory markers (lactoferrin, calprotectin, IL-8) and C. difficile ribotype 027 strain status. Thirty days post enrollment, another serum sample was obtained to compare antibody responses.

RESULTS

Of the 28 pediatric patients enrolled, 27 completed follow-up and 8 (30%) experienced rCDI. At enrollment, children with malignancy had significantly lower stool calprotectin, lactoferrin and IL-8 than those without malignancy. There was a trend toward increased stool inflammatory markers in those who later developed rCDI. The IL-8 A/A genotype was not associated with recurrent disease. No patients were found to have ribotype 027 or an antibody increase to toxin A.

CONCLUSIONS

The rate of rCDI in our pediatric cohort was 30%. Children with rCDI had a trend toward higher fecal inflammatory markers with the initial infection, and these values were lower in children with malignancy. Fecal lactoferrin, calprotectin and IL-8 should be further studied to determine their value in predicting the risk of rCDI in children.

The Attributable Burden of Clostridium difficile Infection to Long-Term Care Facilities Stay: A Clinical Study

BACKGROUND

Advanced age, history of hospitalization, and antibiotic consumption are associated with the pathogenesis of Clostridium difficile infection (CDI). Long-term care facilities (LTCFs) represent a setting where CDI has been increasingly reported. We aimed to estimate the actual attributable burden of CDI to LTCF stay and determine the characteristics of the disease epidemiology in this setting.

DESIGN

IRB-approved retrospective cohort study.

SETTING

LTCF and community.

PARTICIPANTS

One thousand seven hundred and sixty-one patients.

MEASUREMENTS/RESULTS

The prevalence of CDI among LTCF residents was 22.4%, whereas the prevalence of CDI among community residents was 6.7% (P < .001). The prevalence of CDI among LTCF residents was significantly higher in both the 18-64 (P < .001) and the ≥65 age groups (P < .010). Measures of hospital exposure and antibiotic consumption between LTCF and community residents prior to CDI diagnosis were non-significant. A strict matching (1:2) between LTCF and community residents adjusting for age, total number of hospital admissions and antibiotic consumption showed that the odds of CDI for an LTCF resident were 6.89 times larger than the odds for a community resident (OR = 6.89, 95%, 4.67-10.17). For an LTCF resident with CDI, the odds of manifesting severe disease were 3.25 times larger than the odds for a community resident with CDI (OR = 3.25, 95%, 1.81-5.86). LTCF residents were more frequently hospitalized (P = .002) required longer hospital stays for their CDI management (P = .03) and had more recurrent CDI cases than community residents (P = .04).

CONCLUSIONS

Our study highlights the increased burden of CDI among LTCF residents independently of age, antibiotic, and hospitalization background. Severe CDI disease and recurrences are more frequent in LTCFs.

[Adult immunisation: General points, hot topics and perspectives]

Vaccination in immunocompetent adult mainly concerns booster vaccination against diphtheria, tetanus, polio and pertussis. Some chronic diseases may also require the achievement of pneumococcal and influenza vaccines. In addition, from the age of 65, annual influenza vaccination as well as one dose of a live attenuated shingles vaccine between 64 and 75 years are recommended. Immunocompromised adults, due to the increased risk of serious infections responsible of significant morbidity and mortality, are particularly concerned by vaccination. Main issues in this population are the decreased immunogenicity and efficacy of vaccination and the risk of infection with live attenuated vaccines and. Depending on the type of immunosuppression, the recommended vaccines and vaccination schemes differ. Vaccination of healthy persons caring or residing with immunocompromised patients is an important point in the vaccine strategy. The current perspectives in vaccinology concern the development of vaccines against healthcare associated infections (Clostridium difficile and Staphylococcus aureus in particular), the strategy of vaccination during pregnancy to protect new-borns (respiratory syncytial virus, group B streptococcus) and the development of new adjuvants and new routes of immunization. With the overall decline in immunization coverage and increasing distrust of vaccination, the problem of vaccine hesitancy is also a hot topic. The reasons for doubt in the vaccine usefulness and the solutions to be applied are also crucial issues.

Efficacy of Secondary Prophylaxis With Vancomycin for Preventing Recurrent Clostridium difficile Infections

OBJECTIVES

Patients with Clostridium difficile infection (CDI) who are re-exposed to antibiotics have a high likelihood of recurrence. We aimed to determine whether oral vancomycin as secondary prophylaxis reduces the risk of recurrence in patients recently diagnosed with CDI who undergo subsequent antibiotic exposure (CDI-AE).

METHODS

We conducted a retrospective cohort study of patients diagnosed with CDI (initial episode or recurrence) between 2003 and 2011 in two tertiary care centers in Quebec, Canada and who received antibiotics not targeted against CDI within 90 days after their CDI diagnosis. Risk factors for subsequent recurrence after this exposure to antibiotics were assessed through Cox regression analyses.

RESULTS

We included 551 episodes of CDI-AE (379 initial episodes, 172 recurrences). Recurrence occurred after exposure to antibiotics in 181 episodes (32.9%). Recurrence was more likely in older patients (for each additional year of age: adjusted hazard ratio (AHR), 1.01; 95% confidence interval (CI), 1.00-1.03; P=0.02) and among cases where the CDI-AE episode was itself a first (AHR, 3.59; 95% CI, 2.52-5.13; P<0.0001) or a second recurrence (AHR, 4.88; 95% CI, 3.38-7.06; P<0.0001). Oral vancomycin prophylaxis decreased the risk of further recurrence in patients whose CDI-AE itself was a recurrence (AHR, 0.47; 95% CI, 0.32-0.69; P<0.0001) but not in those whose CDI-AE was an initial episode (AHR, 0.91; 95% CI, 0.57-1.45; P=0.68).

CONCLUSIONS

Oral vancomycin appears as an effective strategy for decreasing the risk of further CDI recurrence in patients with a history of recurrent CDI who are re-exposed to antibiotics.

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.

The efficacy of fidaxomicin in the treatment of Clostridium difficile infection in a real-world clinical setting: a Spanish multi-centre retrospective cohort

The objective of this study was to evaluate the efficacy and safety of fidaxomicin in the real-life clinical setting. This was a retrospective cohort of patients with Clostridium difficile infection (CDI) treated with fidaxomicin in 20 Spanish hospitals between July 2013 and July 2014. Clinical cure, 30-day recurrence, 30-day mortality, sustained cure, and factors associated with the failure to achieve sustained cure were analyzed. Of the 72 patients in the cohort 41 (56.9 %) had a fatal underlying disease. There were 44 (61.1 %) recurrent episodes and 26 cases (36.1 %) with a history of multiple recurrences. Most episodes were severe (26, 36 %) or severe-complicated (14, 19.4 %). Clinical cure rate was 90.3 %, recurrence rate was 16.7 % and three patients (4.2 %) died during the follow-up period. Sustained cure was achieved in 52 cases (72.2 %). Adverse events were reported in five cases (6.9 %). Factors associated with the lack of sustained cure were cardiovascular comorbidity (OR 11.4; 95 %CI 1.9-67.8), acute kidney failure (OR 7.4; 95 %CI 1.3-43.1), concomitant systemic antibiotic treatment (OR 6.2; 95 %CI 1.1-36.8), and C-reactive protein value at diagnosis (OR 1.2 for each 1 mg/dl increase; 95 %CI 1.03-1.3). Fidaxomicin is an effective and well tolerable treatment for severe CDI and for cases with elevated recurrence risk.

Gut microbiome predictors of treatment response and recurrence in primary Clostridium difficile infection

BACKGROUND

Clostridium difficile infection (CDI) may not respond to initial therapy and frequently recurs, but predictors of response and recurrence are inconsistent. The impact of specific alterations in the gut microbiota determining treatment response and recurrence in patients with CDI is unknown.

AIM

To assess microbial signatures as predictors of treatment response and recurrence in CDI.

METHODS

Pre-treatment stool samples and clinical metadata including outcomes were collected prospectively from patients with their first CDI episode. Next generation 16s rRNA sequencing using MiSeq Illumina platform was performed and changes in microbial community structure were correlated with CDI outcomes.

RESULTS

Eighty-eight patients (median age 52.7 years, 60.2% female) were included. Treatment failure occurred in 12.5% and recurrence after response in 28.5%. Patients who responded to treatment had an increase in Ruminococcaceae, Rikenellaceae, Clostridiaceae, Bacteroides, Faecalibacterium and Rothia compared to nonresponders. A risk-index built from this panel of microbes differentiated responders (mean 0.07 ± 0.24) from nonresponders (0.52 ± 0.42; P = 0.0002). Receiver operating characteristic (ROC) curve demonstrated that risk-index was a strong predictor of treatment response with an area under the curve (AUC) of 0.85. Among clinical parameters tested, only proton pump inhibitor use predicted recurrent CDI (OR 3.75, 95% CI 1.27-11.1, P = 0.01). Patients with recurrent CDI had statistically significant increases in Veillonella, Enterobacteriaceae, Streptococci, Parabacteroides and Lachnospiraceae compared to patients without recurrence and a risk index was able to predict recurrence (AUC = 0.78).

CONCLUSION

Gut microbiota signatures predict treatment response and recurrence potentially, allowing identification of patients with Clostridium difficile infection that may benefit from early institution of alternate therapies.

A cost-effectiveness and budget impact analysis of first-line fidaxomicin for patients with Clostridium difficile infection (CDI) in Germany

PURPOSE

Clostridium difficile infection (CDI) represents a significant economic healthcare burden, especially the cost of recurrent disease. Fidaxomicin produced significantly lower recurrence rates and higher sustained cure rates in clinical trials. We evaluated the cost-effectiveness and budget impact of fidaxomicin compared with vancomycin in Germany in the first-line treatment of patient subgroups with CDI at increased risk of recurrence.

METHODS

A semi-Markov model was used to compare the cost-effectiveness and budget impact of fidaxomicin vs. vancomycin from a payer perspective in Germany. The model cycle length was 10 days. The time horizon was 1 year. Model inputs were probability of clinical cure, 30-day probability of recurrence, and 30-day attributable mortality based on evidence from two randomized controlled trials comparing fidaxomicin and vancomycin in patients with CDI. Cost-effectiveness outcomes were cost per quality-adjusted life year gained, cost per bed-day saved, and cost per recurrence avoided.

RESULTS

Despite higher drug acquisition costs, fidaxomicin was dominant in the cancer subgroup (less costly and more effective) and cost-effective in the other subgroups, with incremental cost-effectiveness ratios vs. vancomycin ranging from €26,900 to €44,500. Hospitalization costs of the first-line treatment of CDI with fidaxomicin vs. vancomycin were lower in every patient subgroup, resulting in budget impacts ranging from -€1325 (in patients ≥65 years) to -€2438 (in cancer patients). Reductions in the cost of treating recurrence with fidaxomicin ranged from -€574.32 per patient in those receiving concomitant antibiotics to -€1500.68 per patient in renally impaired patients.

CONCLUSIONS

In patient subgroups with CDI at increased recurrence risk, fidaxomicin was cost-effective vs. vancomycin, and less costly and more effective in patients with cancer.

Comparison of the safety, tolerability, and pharmacokinetics of fidaxomicin in healthy Japanese and caucasian subjects

Background and Objectives

Fidaxomicin treatment of Clostridium difficile infection is known to produce minimal systemic exposure, as the antibacterial (antibiotic) remains primarily in the gut. In this randomized, double-blind, placebo-controlled study, the safety, tolerability, and pharmacokinetics of single and multiple ascending doses of fidaxomicin were evaluated in healthy Japanese and Caucasian subjects.

Methods

Thirty-six healthy subjects were randomly assigned in a 3:1 ratio to receive either fidaxomicin or placebo. Cohort 1 (100 mg) and Cohort 2 (200 mg) comprised 12 Japanese subjects each and Cohort 3 (200 mg) comprised 12 Caucasian subjects. Subjects received a single dose of the study drug on Day 1 and received multiple doses for 10 days after a wash-out period.

Results

After multiple 200 mg dosing of fidaxomicin, both mean maximum plasma concentrations (C_max) in Japanese (8.7 ± 5.3 ng/mL) and Caucasian (7.0 ± 3.7 ng/mL) subjects and the area under the concentration–time curve (AUC) were higher in Japanese subjects (58.5 ± 36.7 ng·h/mL) than in Caucasian subjects (37.6 ± 15.7 ng·h/mL), although variation in both groups was large. The mean fecal concentrations of fidaxomicin in Japanese and Caucasian subjects were 2669 and 2181 μg/g, respectively. The possibly study drug-related adverse events were diarrhea (n = 1), feeling hot (n = 1), and hypersomnia (n = 2), which were mild in severity.

Conclusions

In both Japanese and Caucasian subjects, fidaxomicin demonstrated similarly minimal systemic absorption, and was mainly excreted in feces. Fidaxomicin was safe and well-tolerated in all subjects.

Antibodies to Toxin B Are Protective Against Clostridium difficile Infection Recurrence

BACKGROUND

Although newer studies have evaluated risk factors for recurrent Clostridium difficile infection (CDI), the vast majority did not measure important biomarkers such as endogenous anti-toxin A and anti-toxin B antibody levels.

METHODS

Data from the placebo group of a phase 2 trial testing monoclonal antibodies to C. difficile toxins A and B for preventing CDI recurrence (rCDI) were analyzed to assess risk factors associated with rCDI. Patients with symptomatic CDI taking metronidazole or vancomycin were enrolled. The primary outcome was rCDI within 84 days of treatment start. Univariate and multivariate logistic regression was used to examine associations between potential risk factors and rCDI. At baseline, demographic and clinical characteristics were recorded; endogenous antibody levels were assessed using 2 enzyme-linked immunosorbent assays.

RESULTS

A predictor of recurrence was age ≥65 years, and an antibody-mediated immune response to toxin B appears to be protective against rCDI.

CONCLUSIONS

Our findings demonstrate the importance of clinical as well as immunological risk factors in rCDI and provide more robust evidence for the protective effects of antibody to toxin B in the prevention of rCDI.

CLINICAL TRIALS REGISTRATION

NCT00350298.

Epidemiological and economic burden of Clostridium difficile in the United States: estimates from a modeling approach

BACKGROUND

Despite a large increase in Clostridium difficile infection (CDI) severity, morbidity and mortality in the US since the early 2000s, CDI burden estimates have had limited generalizability and comparability due to widely varying clinical settings, populations, or study designs.

METHODS

A decision-analytic model incorporating key input parameters important in CDI epidemiology was developed to estimate the annual number of initial and recurrent CDI cases, attributable and all-cause deaths, economic burden in the general population, and specific number of high-risk patients in different healthcare settings and the community in the US. Economic burden was calculated adopting a societal perspective using a bottom-up approach that identified healthcare resources consumed in the management of CDI.

RESULTS

Annually, a total of 606,058 (439,237 initial and 166,821 recurrent) episodes of CDI were predicted in 2014: 34.3 % arose from community exposure. Over 44,500 CDI-attributable deaths in 2014 were estimated to occur. High-risk susceptible individuals representing 5 % of the total hospital population accounted for 23 % of hospitalized CDI patients. The economic cost of CDI was $5.4 billion ($4.7 billion (86.7 %) in healthcare settings; $725 million (13.3 %) in the community), mostly due to hospitalization.

CONCLUSIONS

A modeling framework provides more comprehensive and detailed national-level estimates of CDI cases, recurrences, deaths and cost in different patient groups than currently available from separate individual studies. As new treatments for CDI are developed, this model can provide reliable estimates to better focus healthcare resources to those specific age-groups, risk-groups, and care settings in the US where they are most needed. (Trial Identifier ClinicaTrials.gov: NCT01241552).

Evaluation of the VIDAS glutamate dehydrogenase assay for the detection of Clostridium difficile

We evaluated the performance of the VIDAS GDH assay for the detection of Clostridium difficile. In total, 350 fecal specimens collected from patients clinically suspected of having CDI were analyzed by C. difficile culture and enzyme-linked fluorescent immunoassay (VIDAS GDH); the results were compared with those of toxigenic C. difficile culture (TC), PCR (Xpert C. difficile assay), and toxin AB EIA (VIDAS CDAB). The numbers of culture-positive and culture-negative samples were 108 and 242, respectively. The concordance between the GDH assay and C. difficile culture was 90.3%. With PCR, 12 more samples were found to be positive in GDH-positive/C. difficile culture-negative specimens. Thus, the concordance between GDH assay and C. difficile culture/PCR was 93.7%. The sensitivity, specificity, positive predictive value, and negative predictive value of the VIDAS GDH assay were 97.2%, 87.2%, 77.2%, and 98.6%, respectively, based on the C. difficile culture, and 97.5%, 91.7%, 86.0%, and 98.6%, respectively, based on C. difficile culture/PCR. Positivity rates of the GDH assay were partially associated with those of semi-quantitative C. difficile cultures, which were maximized in grade 3 (>100 colony-forming unit [CFU]) compared with grade 1 (<10 CFU). We evaluated the two-step or three-step algorithm using GDH assay as a first step. No toxin EIA-positive case was found among GDH-negative samples, and 60.8% (48/79) were TC- and/or PCR-positive among the GDH-positive/toxin EIA-negative samples. Thus, approximately 25% of the 350 samples required a confirmatory test (TC or PCR) in the GDH-toxin EIA algorithm, whereas only 2.3% of the total samples in GDH-PCR algorithm was discrepant and required another confirmatory test like TC.

Clostridium difficile infection in patients hospitalized with type 2 diabetes mellitus and its impact on morbidity, mortality, and the costs of inpatient care

AIMS

Type 2 diabetes mellitus (T2DM) is often complicated by infections leading to hospitalization, increased morbidity, and mortality. Not much is known about the impact of Clostridium difficile infection (CDI) on health outcomes in hospitalized patients with T2DM. We estimated the prevalence and temporal trends of CDI; evaluated the associations between CDI and in-hospital mortality, length of stay (LOS), and the costs of inpatient care; and compared the impact of CDI with that of other infections commonly seen in patients with T2DM.

METHODS

We conducted a cross-sectional analysis using data from the Nationwide Inpatient Sample among patients ⩾18years with T2DM and generalized linear regression was used to analyze associations and jointpoint regression for trends.

RESULTS

The prevalence of CDI was 6.8 per 1000 hospital discharges. Patients with T2DM and CDI had increased odds of in-hospital mortality (OR, 3.63; 95% CI 3.16, 4.17). The adjusted mean LOS was higher in patients with CDI than without CDI (11.9 vs. 4.7days). That translated to average hospital costs of $23,000 and $9100 for patients with and without CDI, respectively. The adjusted risk of mortality in patients who had CDI alone (OR 3.75; 95% CI 3.18, 4.41) was similar to patients who had CDI in addition to other common infections (OR 3.25; 95% CI 2.58, 4.10).

CONCLUSION

CDI is independently associated with poorer health outcomes in patients with T2DM. We recommend close surveillance for CDI in hospitalized patients and further studies to determine the cost effectiveness of screening for CDI among patients with T2DM.

Fidaxomicin versus Vancomycin in the Treatment of Clostridium difficile Infection: Canadian Outcomes

Background. This analysis examined the efficacy of fidaxomicin versus vancomycin in 406 Canadian patients with Clostridium difficile infection (CDI), based on data from 2 randomized, clinical trials. Methods. Patients received fidaxomicin or vancomycin 1. Patients were assessed for clinical response recurrence of infection and sustained clinical response for 28 days after treatment completion. Patients at increased risk of recurrence were subjected to subgroup analyses. Results. Clinical response rates for fidaxomicin (90.0%) were noninferior to those with vancomycin (92.2%; 95% confidence interval for difference: −7.7, 3.5). However, fidaxomicin-treated patients had lower recurrence (14.4% versus 28.0%, p = 0.001) and higher sustained clinical response (77.1% versus 66.3%, p = 0.016). Compared with vancomycin, fidaxomicin was associated with lower recurrence rates in all subgroups, reaching statistical significance in patients with age ≥ 65 years (16.0% versus 30.9%, p = 0.026), concomitant antibiotic use (16.2% versus 38.7%, p = 0.036), and non-BI strains (11.8% versus 28.3%, p = 0.004). Higher sustained clinical response rates were observed for fidaxomicin compared with vancomycin in all subgroups; this was statistically significant in the non-BI subgroup (82.8% versus 69.1%, p = 0.021). Conclusions. In Canadian patients, fidaxomicin was superior to vancomycin in sustaining clinical response and reducing CDI recurrence.

Vaccines for Healthcare-associated Infections: Promise and Challenge

As antibiotic resistance increases and the rate of antibiotic development slows, it is becoming more urgent to develop novel approaches to prevent and mitigate serious bacterial and fungal infections. Healthcare-associated infections (HAIs), including those caused by Clostridium difficile, Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, carbapenem-resistant Enterobacteriaceae, and Candida species, are a major cause of morbidity, mortality, and healthcare costs. HAIs are also a key driver of antibiotic use. Vaccines directed toward these pathogens could help prevent a large number of HAIs and associated antibiotic use if administered to targeted populations. Despite numerous scientific and operational challenges, there are vaccine candidates in late-stage clinical development for C. difficile, S. aureus, and P. aeruginosa Basic, preclinical, and early clinical research to develop vaccines for other types of HAIs is also under way. In addition, other prophylactic immune interventions, such as monoclonal antibodies, for several of these pathogens are in advanced development. Here we describe the promise, challenges, and current pipeline of vaccines to prevent HAIs.

Impact on toxin production and cell morphology in Clostridium difficile by ridinilazole (SMT19969), a novel treatment for C. difficile infection

OBJECTIVES

Ridinilazole (SMT19969) is a narrow-spectrum, non-absorbable antimicrobial with activity against Clostridium difficile undergoing clinical trials. The purpose of this study was to assess the pharmacological activity of ridinilazole and assess the effects on cell morphology.

METHODS

Antibiotic killing curves were performed using the epidemic C. difficile ribotype 027 strain, R20291, using supra-MIC (4× and 40×) and sub-MIC (0.125×, 0.25× and 0.5×) concentrations of ridinilazole. Following exposure, C. difficile cells were collected for cfu counts, toxin A and B production, and morphological changes using scanning electron and fluorescence microscopy. Human intestinal cells (Caco-2) were co-incubated with ridinilazole-treated C. difficile growth medium to determine the effects on host inflammatory response (IL-8).

RESULTS

Treatment at supra-MIC concentrations (4× and 40× MIC) of ridinilazole resulted in a significant reduction in vegetative cells over 72 h (4 log difference, P < 0.01) compared with controls without inducing spore formation. These results correlated with a 75% decrease in toxin A production (P < 0.05) and a 96% decrease in toxin B production (P < 0.05). At sub-MIC levels (0.5× MIC), toxin A production was reduced by 91% (P < 0.01) and toxin B production was reduced by 100% (P < 0.001), which resulted in a 74% reduction in IL-8 release compared with controls (P < 0.05). Sub-MIC (0.5×)-treated cells formed filamentous structures ∼10-fold longer than control cells. Following fluorescence labelling, the cell septum was not forming in sub-MIC-treated cells, yet the DNA was dividing.

CONCLUSIONS

Ridinilazole had robust killing effects on C. difficile that significantly reduced toxin production and attenuated the inflammatory response. Ridinilazole also elicited significant cell division effects suggesting a potential mechanism of action.

Clostridium difficile recurrences in Stockholm

Sixty-eight hospital-admitted patients with a first episode of Clostridium difficile infection (CDI) were included and followed up during 1 year. Faeces samples were collected at 1, 2, 6 and 12 months after inclusion and analyzed for the presence of C. difficile toxin B, genes for toxin A, toxin B, binary toxin and TcdC deletion by PCR. All strains were also PCR-ribotyped and the MICs of the isolates were determined against eight antimicrobial agents. In 68 patients initially included, antibiotics, clinical signs and co-morbidities were analyzed and 56 were evaluable for recurrences. The mean number of different antibiotics given during 3 months prior to inclusion was 2.6 (range 0-6). Six patients had not received any antibiotics and three of them had diagnosed inflammatory bowel disease. Thirty-two patients (57%) had either a microbiological or clinical recurrence, 16 of whom had clinical recurrences that were confirmed microbiologically (13, 23%) or unconfirmed by culture (3, 5%). Twenty-nine patients were positive in at least one of the follow-up tests, 16 had the same ribotype in follow-up tests, i.e. relapse, and 13 a different ribotype, i.e., reinfection. Most common ribotypes were 078/126, 020, 023, 026, 014/077, 001 and 005. No strain of ribotype 027 was found. Strains ribotype 078/126 and 023 were positive for binary toxin and were the strains most prone to cause recurrence. All strains were sensitive to vancomycin and metronidazole. Patients with recurrences were significantly older (p = 0.02) and all patients had a high burden of comorbidities, which could explain the high fatality rate, 26 (38%) patients died during the 1-year follow-up.

Comparison of pediatric and adult antibiotic-associated diarrhea and Clostridium difficile infections

Antibiotic-associated diarrhea (AAD) and Clostridum difficile infections (CDI) have been well studied for adult cases, but not as well in the pediatric population. Whether the disease process or response to treatments differs between pediatric and adult patients is an important clinical concern when following global guidelines based largely on adult patients. A systematic review of the literature using databases PubMed (June 3, 1978-2015) was conducted to compare AAD and CDI in pediatric and adult populations and determine significant differences and similarities that might impact clinical decisions. In general, pediatric AAD and CDI have a more rapid onset of symptoms, a shorter duration of disease and fewer CDI complications (required surgeries and extended hospitalizations) than in adults. Children experience more community-associated CDI and are associated with smaller outbreaks than adult cases of CDI. The ribotype NAP1/027/BI is more common in adults than children. Children and adults share some similar risk factors, but adults have more complex risk factor profiles associated with more co-morbidities, types of disruptive factors and a wider range of exposures to C. difficile in the healthcare environment. The treatment of pediatric and adult AAD is similar (discontinuing or switching the inciting antibiotic), but other treatment strategies for AAD have not been established. Pediatric CDI responds better to metronidazole, while adult CDI responds better to vancomycin. Recurrent CDI is not commonly reported for children. Prevention for both pediatric and adult AAD and CDI relies upon integrated infection control programs, antibiotic stewardship and may include the use of adjunctive probiotics. Clinical presentation of pediatric AAD and CDI are different than adult AAD and CDI symptoms. These differences should be taken into account when rating severity of disease and prescribing antibiotics.

Cost-Effectiveness Analysis of Six Strategies to Treat Recurrent Clostridium difficile Infection

Objective

To assess the cost-effectiveness of six treatment strategies for patients diagnosed with recurrent Clostridium difficile infection (CDI) in Canada: 1. oral metronidazole; 2. oral vancomycin; 3.oral fidaxomicin; 4. fecal transplantation by enema; 5. fecal transplantation by nasogastric tube; and 6. fecal transplantation by colonoscopy.

Perspective

Public insurer for all hospital and physician services.

Setting

Ontario, Canada.

Methods

A decision analytic model was used to model costs and lifetime health effects of each strategy for a typical patient experiencing up to three recurrences, over 18 weeks. Recurrence data and utilities were obtained from published sources. Cost data was obtained from published sources and hospitals in Toronto, Canada. The willingness-to-pay threshold was $50,000/QALY gained.

Results

Fecal transplantation by colonoscopy dominated all other strategies in the base case, as it was less costly and more effective than all alternatives. After accounting for uncertainty in all model parameters, there was an 87% probability that fecal transplantation by colonoscopy was the most beneficial strategy. If colonoscopy was not available, fecal transplantation by enema was cost-effective at $1,708 per QALY gained, compared to metronidazole. In addition, fecal transplantation by enema was the preferred strategy if the probability of recurrence following this strategy was below 8.7%. If fecal transplantation by any means was unavailable, fidaxomicin was cost-effective at an additional cost of $25,968 per QALY gained, compared to metronidazole.

Conclusion

Fecal transplantation by colonoscopy (or enema, if colonoscopy is unavailable) is cost-effective for treating recurrent CDI in Canada. Where fecal transplantation is not available, fidaxomicin is also cost-effective.

Toxin B PCR cycle threshold as a predictor of poor outcome of Clostridium difficile infection: a derivation and validation cohort study

OBJECTIVES

Prediction of patients with poor outcome is necessary in order to plan the proper management of Clostridium difficile infection (CDI); however, clinical criteria are insufficient. In a previous study, we observed that high toxigenic C. difficile cfu stool counts at diagnosis were associated with a poor outcome. Our objective was to investigate the role of the PCR toxin B amplification cycle threshold (Ct) in the prediction of CDI poor outcome and to derive and validate a high-risk prediction rule using this marker.

METHODS

We prospectively included patients with CDI (derivation cohort, January 2013 to June 2014; and validation cohort, December 2014 to May 2015), who were followed for at least 2 months after their last episode/recurrence. All samples were tested with Xpert™ C. difficile.

RESULTS

For the derivation cohort (n = 129) toxin B Ct was independently associated with poor outcome (P < 0.001). The receiver operating characteristic (ROC) curve yielded an AUC of 0.816. Using a cut-off of <23.5 cycles for high risk of poor outcome, the diagnostic accuracy was 81.4%, the sensitivity was 46.5% (95% CI 32.5-61.1) and the specificity was 98.8% (95% CI 93.7-99.8). For the validation cohort (n = 170), the diagnostic accuracy was 81.8%, the sensitivity was 88.4% (95% CI 75.5-94.9) and the specificity was 79.5% (95% CI 71.7-85.6). The ROC curve yielded an AUC of 0.857.

CONCLUSIONS

Low toxin B Ct values from samples collected at the initial moment of diagnosis appears to be a strong marker for poor outcome. This available test may identify, at an early stage, patients who are at higher risk of a poor outcome CDI.

First recurrence of Clostridium difficile infection: clinical relevance, risk factors, and prognosis

Therapy for recurrent Clostridium difficile-associated diarrhea (CDAD) is challenging. We evaluated the frequency, associated risk factors, and prognosis of first CDAD recurrences. Prospective cohort study of all consecutive cases of primary CDAD diagnosed in a university hospital from January 2006 to June 2013. Recurrent infection was defined as reappearance of symptoms within 8 weeks of the primary diagnosis, provided that CDAD symptoms had previously resolved and a new toxin test was positive. Predictors of a first episode of recurrent CDAD were determined by logistic regression analysis. In total, 502 patients (51.6 % men) with a mean age of 62.3 years (SD 18.5) had CDAD; 379 (76 %) were cured, 61 (12 %) had a first recurrence, 52 (10 %) died within 30 days of the CDAD diagnosis, nine (2 %) required colectomy, and one was lost to follow-up. Among the 61 patients with a first recurrence, 36 (59.3 %) were cured, 15 (23.7 %) had a second recurrence, nine (15.3 %) died, and one (1.7 %) required colectomy. On multivariate analysis, age older than 65 years (OR 2.04; 95 % CI, 1.14-3.68; P < 0.02) and enteral nutrition (OR, 3.62; 95%CI, 1.66-7.87; P < 0.01) were predictors of a first recurrence. A risk score was developed for first CDAD recurrence using the predictive factors and selected biological variables. In our CDAD cohort, 12 % of patients had a first recurrence of this disease, in which the prognosis was less favorable than that of the primary episode, as it heralded a higher risk of additional recurrences. Patient age and enteral nutrition were predictors of a first recurrence.

Risk factors for recurrent Clostridium difficile infection in allogeneic hematopoietic cell transplant recipients

Clostridium difficile infection (CDI) is one of the leading causes of hospital-acquired infections in recent times. Hematopoietic stem cell transplantation (HSCT) confers increased risk for CDI because of prolonged hospital stay, immunosuppression, the need to use broad-spectrum antibiotics and a complex interplay of preparative regimen and GvHD-induced gut mucosal damage. Our study evaluated risk factors (RF) for recurrent CDI in HSCT recipients given the ubiquity of traditional RF for CDI in this population. Of the 499 allogeneic HSCT recipients transplanted between 2005 and 2012, 61 (12%) developed CDI within 6 months before transplant or 2 years after transplant and were included in the analysis. Recurrent CDI occurred in 20 (33%) patients. One year incidence of CDI recurrence was 31%. Multivariable analyses identified the number of antecedent antibiotics other than those used to treat CDI as the only significant RF for recurrence (hazard ratio 1.96, 95% confidence interval 1.09-3.52, P=0.025). Most recurrences occurred within 6 months of the first CDI, and the recurrence of CDI was associated with a trend for increased risk of mortality. This prompts the need for further investigation into secondary prophylaxis to prevent recurrent CDI.

Recurrent Clostridium difficile infection and the microbiome

The diverse and densely populated gastrointestinal microbiota is essential for the regulation of host physiology and immune function. As our knowledge of the composition and function of the intestinal microbiota continues to expand, there is new interest in using these developments to tailor fecal microbiota transplantation (FMT) and microbial ecosystem therapeutics (MET) for a variety of diseases. The potential role of FMT and MET in the treatment of Clostridium difficile infection (CDI)-currently the leading nosocomial gastrointestinal infection-has proven highly effective for recurrent CDI, and has emerged as a paradigm shift in the treatment of this disease. The current review will serve as a summary of the key aspects of CDI, and will introduce the essential framework and challenges of FMT, as is currently practiced. MET represents the progression of conventional bacteriotherapy that fundamentally capitalizes on the restorative properties of intestinal bacterial communities and may be viewed as the culmination of a rationally designed therapeutic modality. As our understanding of the composition and function of the intestinal microbiota evolves, it will likely drive next-generation microbiota therapies for a range of medical conditions, such as inflammatory bowel disease, obesity, and metabolic syndrome.

Clostridium difficile infection in patients with liver disease: a review

Over the past two decades, there has been a dramatic worldwide increase in both the incidence and severity of Clostridium difficile infection (CDI). Paralleling the increased incidence of CDI in the general population, there has been increased interest in CDI among patients with liver disease, particularly in those with liver cirrhosis and post liver transplantation. MEDLINE and several other electronic databases from January 1995 to December 2014 were searched in order to identify potentially relevant literature. Patients with cirrhosis and liver transplant recipients are at high risk for the development CDI because of antibiotics and proton pump inhibitors use, frequent and prolonged hospitalization, immunosuppressant therapy, and multiple comorbidities. Enzyme immunoassay to detect C. difficile toxins A and B in stool remains the most widely used test for CDI diagnosis, although, more recently, polymerase chain reaction (PCR)-based assays have become the preferred diagnostic test in many laboratories. Metronidazole and vancomycin, given orally, have proved to be effective in the treatment of CDI. Both cirrhotic patients and liver transplant recipients with CDI have longer length of hospital stay, increased mortality, and higher healthcare costs than those without CDI. A rapid diagnosis and adequate therapy of CDI are of paramount importance to improve liver disease patients' outcome. The aim of this review is to provide up-to-date information on the epidemiology, risk factors, pathogenesis, treatment, and outcomes in liver disease patients with CDI.

Clostridium difficile outbreak caused by NAP1/BI/027 strain and non-027 strains in a Mexican hospital

Background

Clostridium difficile infections caused by the NAP1/B1/027 strain are more severe, difficult to treat, and frequently associated with relapses.

Methods

A case–control study was designed to examine a C. difficile infection (CDI) outbreak over a 12-month period in a Mexican hospital. The diagnosis of toxigenic CDI was confirmed by real-time polymerase chain reaction, PCR (Cepheid Xpert C. difficile/Epi).

Results

During the study period, 288 adult patients were evaluated and 79 (27.4%) patients had confirmed CDI (PCR positive). C. difficile strain NAP1/B1/027 was identified in 31 (39%) of the patients with confirmed CDI (240 controls were included). Significant risk factors for CDI included any underlying disease (p < 0.001), prior hospitalization (p < 0.001), and antibiotic (p < 0.050) or steroid (p < 0.001) use. Laboratory abnormalities included leukocytosis (p < 0.001) and low serum albumin levels (p < 0.002). Attributable mortality was 5%. Relapses occurred in 10% of patients. Risk factors for C. difficile NAP1/B1/027 strain infections included prior use of quinolones (p < 0.03).

Risk factors for CDI caused by non-027 strains included chronic cardiac disease (p < 0.05), chronic renal disease (p < 0.009), and elevated serum creatinine levels (p < 0.003). Deaths and relapses were most frequent in the 027 group (10% and 19%, respectively).

Conclusions

C. difficile NAP1/BI/027 strain and non-027 strains are established pathogens in our hospital. Accordingly, surveillance of C. difficile infections is now part of our nosocomial prevention program.

Risk Factors for Recurrent Clostridium difficile Infections and Strategies to Decrease Readmissions in a Community Hospital

BACKGROUND

Currently there are no universally accepted approaches for the prevention of recurrent Clostridium difficile infections (CDI) following the initial infection. Several studies have identified common risk factors for the emergence of recurrent CDI. Identifying patients at high risk for recurrent CDI through the assessment of risk factors at initial diagnosis could enable health care providers to optimize available treatment options. A vancomycin hydrochloride-tapered regimen may be an effective treatment option for the prevention of recurrent CDI following the initial infection.

METHODS

In this single-center, prospective study, we examined the efficacy of orally administered vancomycin-tapered regimens for the prevention of recurrent CDI in high-risk patients. High-risk patients were identified using patient risk factors found in a retrospective chart review. The primary objective was to decrease hospital readmissions for recurrent CDI. The secondary objective was to improve the discharge coordination-of-care process by providing a pharmacy benefits evaluation, which ensured vancomycin affordability and assistance in prescription attainment, and discharge counseling.

RESULTS

Of the 83 patients enrolled in the study, 5 experienced recurrent CDI (6%). Memorial Health Care System's (Chattanooga, Tennessee) historical recurrent CDI rate was 8.2%. Thirty-one of the 83 patients received a vancomycin-tapered regimen following their initial infection (37%). A pharmacy benefits evaluation was performed on 35 of the 57 patients who were discharged home on vancomycin (61%).

CONCLUSIONS

Vancomycin-tapered regimens may provide a cost-effective method for the prevention of recurrent CDI following an initial infection in patients at high risk for recurrence.

Economic burden of Clostridium difficile in five hospitals of the Florence health care system in Italy

INTRODUCTION

Despite the awareness about the increasing rates of Clostridium difficile infection (CDI) and the economic burden arising from its management (prolonged hospitalization, laboratory tests, visits, surgical treatment, environmental sanitation), few studies are available in Italy on the economic costs directly attributable to the CDI. The Florence health care system has designed a study with the aim of describing the costs attributable to the CDI and defines the incremental economic burden associated with the management of this complication.

METHODS

We conducted a retrospective study in five hospitals of the Florence health care system. The enrolled population included all patients who were hospitalized during the year 2013 with a diagnosis of CDI. Of the 187 total cases reported in 2013, 69 patients were enrolled, for whom the main cause of hospitalization was directly attributable to CDI.

RESULTS

We enrolled 69 patients (19 males and 50 females), with a mean age of 82.16 years (minimum 46 to maximum 98). The total number of hospitalization days observed was 886 (12.8 per patient on average). The data from this study show that the mean total incremental cost for a patient with CDI was €3,270.52 per year. The hospital stay length is the most significant cost parameter, having the largest influence on the overall costs, with an impact of 87% on the total cost. The results confirm the costs for the management of CDI in five hospitals of the Florence health care system are in line with data from the international literature.

CONCLUSION

The economic impact of CDI is most evident in the extension of the duration of hospitalization and emergency recurrences requiring new therapeutic options with the need to develop and implement new diagnostic and therapeutic algorithms in clinical practice.

Clinical and Healthcare Burden of Multiple Recurrences of Clostridium difficile Infection

BACKGROUND

Clostridium difficile infection (CDI) is associated with a high risk of recurrence (rCDI). Few studies have focused on multiple recurrences. To evaluate the potential of novel treatments targeting recurrence, we assessed the burden and severity of rCDI.

METHODS

This was a retrospective cohort of adults diagnosed with CDI in a hospital in Sherbrooke, Canada (1998-2013). An rCDI episode was defined by the reappearance of diarrhea leading to a treatment, with or without a positive toxin assay, within 14-60 days after the previous episode.

RESULTS

We included 1527 patients. The probability of developing a first rCDI was 25% (354/1418); a second, 38% (128/334); a third, 29% (35/121); and a fourth or more, 27% (9/33). Two or more rCDIs were observed in 9% (128/1389) of patients. The risk of a first recurrence fluctuated over time, but there was no such variation for second or further recurrences. The proportion of severe cases decreased (47% for initial episodes, 31% for first recurrences, 25% for second, 17% for third), as did the risk of complicated CDI (5.8% to 2.8%). The severity and risk of complications of first recurrences decreased over time, while oral vancomycin was used more systemically. A hospital admission was needed for 34% (148/434) of recurrences.

CONCLUSIONS

This study documented the clinical and healthcare burden of rCDI: 34% of patients with rCDI needed admission, 28% developed severe CDI, and 4% developed a complication. Secular changes in the severity of recurrences could reflect variations in the predominant strain, or better management.

WSES guidelines for management of Clostridium difficile infection in surgical patients

In the last two decades there have been dramatic changes in the epidemiology of Clostridium difficile infection (CDI), with increases in incidence and severity of disease in many countries worldwide. The incidence of CDI has also increased in surgical patients. Optimization of management of C difficile, has therefore become increasingly urgent. An international multidisciplinary panel of experts prepared evidenced-based World Society of Emergency Surgery (WSES) guidelines for management of CDI in surgical patients.

Risk for Clostridium difficile infection after radical cystectomy for bladder cancer: Analysis of a contemporary series

INTRODUCTION

This study seeks to evaluate the incidence and associated risk factors of Clostridium difficile infection (CDI) in patients undergoing radical cystectomy (RC) for bladder cancer.

METHODS

We retrospectively reviewed a single institution׳s bladder cancer database including all patients who underwent RC between 2010 and 2013. CDI was diagnosed by detection of Clostridium difficile toxin B gene using polymerase chain reaction-based stool assay in patients with clinically significant diarrhea within 90 days of the index operation. A multivariable logistic regression model was used to identify demographics and perioperative factors associated with developing CDI.

RESULTS

Of the 552 patients who underwent RC, postoperative CDI occurred in 49 patients (8.8%) with a median time to diagnosis after RC of 7 days (interquartile range: 5-19). Of the 122 readmissions for postoperative complications, 10% (n = 12) were related to CDI; 2 patients died of sepsis directly related to severe CDI. On multivariate logistic regression, the use of chronic antacid therapy (odds ratio = 1.9, 95% CI: 1.02-3.68, P = 0.04) and antibiotic exposure greater than 7 days (odds ratio = 2.2, 95% CI: 1.11-4.44, P = 0.02) were independently associated with developing CDI. The use of preoperative antibiotics for positive findings on urine culture within 30 days before surgery was not statistically significantly associated with development of CDI (P = 0.06).

CONCLUSIONS

The development of CDI occurs in 8.8% of patients undergoing RC. Our study demonstrates that use of chronic antacid therapy and long duration of antimicrobial exposure are associated with development of CDI. Efforts focusing on minimizing antibiotic exposure in patients undergoing RC are needed, and perioperative antimicrobial prophylaxis guidelines should be followed.

Recurrent Clostridium difficile infection: From colonization to cure

Clostridium difficile infection (CDI) is increasingly prevalent, dangerous and challenging to prevent and manage. Despite intense national and international attention the incidence of primary and of recurrent CDI (PCDI and RCDI, respectively) have risen rapidly throughout the past decade. Of major concern is the increase in cases of RCDI resulting in substantial morbidity, morality and economic burden. RCDI management remains challenging as there is no uniformly effective therapy, no firm consensus on optimal treatment, and reliable data regarding RCDI-specific treatment options is scant. Novel therapeutic strategies are critically needed to rapidly, accurately, and effectively identify and treat patients with, or at-risk for, RCDI. In this review we consider the factors implicated in the epidemiology, pathogenesis and clinical presentation of RCDI, evaluate current management options for RCDI and explore novel and emerging therapies.

Risk Factors for In-Hospital Mortality among a Cohort of Children with Clostridium difficile Infection

OBJECTIVE

The incidence of Clostridium difficile infection (CDI) has increased and has been associated with poor outcomes among hospitalized children, including increased risk of death. The purpose of this study was to identify risk factors for all-cause in-hospital mortality among children with CDI.

METHODS

A multicenter cohort of children with CDI, aged 1–18 years, was established among children hospitalized at 41 freestanding children’s hospitals between January 1, 2006 and August 31, 2011. Children with CDI were identified using a validated case-finding tool (ICD-9-CM code for CDI plus C. difficile test charge). Only the first CDI-related hospitalization during the study period was used. Risk factors for all-cause in-hospital mortality within 30 days of C. difficile test were evaluated using a multivariable logistic regression model.

RESULTS

We identified 7,318 children with CDI during the study period. The median age of this cohort was 6 years [interquartile range (IQR): 2–13]; the mortality rate was 1.5% (n=109); and the median number of days between C. difficile testing and death was 12 (IQR, 7–20). Independent risk factors for death included older age [adjusted odds ratio (OR, 95% confidence interval), 2.29 (1.40–3.77)], underlying malignancy [3.57 (2.36–5.40)], cardiovascular disease [2.06 (1.28–3.30)], hematologic/immunologic condition [1.89 (1.05–3.39)], gastric acid suppression [2.70 (1.43–5.08)], and presence of >1 severity of illness marker [3.88 (2.44–6.19)].

CONCLUSION

Patients with select chronic conditions and more severe disease are at increased risk of death. Identifying risk factors for in-hospital mortality can help detect subpopulations of children that may benefit from targeted CDI prevention and treatment strategies.

Infect Control Hosp Epidemiol 2015;36(10):1183–1189

Emergence of community-acquired Clostridium difficile infection: the experience of a French hospital and review of the literature

BACKGROUND

Clostridium difficile infection (CDI) is a common cause of nosocomial diarrhoea. People in the general community are not usually considered to be at risk of CDI. CDI is associated with a high risk of morbidity and mortality. The risk of severity is defined by the Clostridium Severity Index (CSI).

METHODS

The cases of 136 adult patients with CDI treated at the University Hospital of Tours, France between 2008 and 2012 are described. This was a retrospective study.

RESULTS

Among the 136 patients included, 62 were men and 74 were women. Their median age was 64.4 years (range 18-97 years). Twenty-six of the 136 (19%) cases were community-acquired (CA) and 110 (81%) were healthcare-acquired (HCA). The major risk factors for both groups were long-term treatment with proton pump inhibitors (54% of CA, 53% of HCA patients) and antibiotic treatment within the 2.5 months preceding the CDI (50% of CA, 91% of HCA). The CSI was higher in the CA-CDI group (1.56) than in the HCA-CDI group (1.39). Intensive care was required for 8% of CA-CDI and 16.5% of HCA-CDI patients.

CONCLUSIONS

CDI can cause community-acquired diarrhoea, and CA-CDI may be more severe than HCA-CDI. Prospective studies of CDI involving people from the general community without risk factors are required to confirm this observation.

The epidemiology of Clostridium difficile infection inside and outside health care institutions

This article describes the global changes in Clostridium difficile epidemiology since the late twentieth century and into the twenty-first century when the new epidemic strain BI/NAP1/027 emerged. The article provides an overview of how understanding of C difficile epidemiology has rapidly evolved since its initial association with colitis in 1974. It also discusses how C difficile has spread across the globe, the role of asymptomatic carriers in disease transmission, the increased recognition of C difficile outside health care settings, the changes in epidemiology of C difficile infection in children, and the risk factors for disease.

Clostridium difficile in the Long-Term Care Facility: Prevention and Management

Residents of long-term care facilities are at high risk for Clostridium difficile infection due to frequent antibiotic exposure in a population already rendered vulnerable to infection due to advanced age, multiple comorbid conditions and communal living conditions. Moreover, asymptomatic carriage of toxigenic C. difficile and recurrent infections are prevalent in this population. Here, we discuss epidemiology and management of C. difficile infection among residents of long-term care facilities. Also, recognizing that both the population and culture differs significantly from that of hospitals, we also address prevention strategies specific to LTCFs.

Whole-genome sequencing improves discrimination of relapse from reinfection and identifies transmission events among patients with recurrent Clostridium difficile infections

BACKGROUND

Recurrent Clostridium difficile infection (CDI) represents a significant healthcare challenge. Patients may suffer multiple episodes of CDI with the index strain (relapse) or become infected by another strain acquired nosocomially (reinfection).

AIM

We aimed to characterize C. difficile isolates causing recurrent CDI at a tertiary referral hospital by whole-genome sequencing (WGS) to assess strain similarities at the highest level of genetic resolution and accurately detect relapse, reinfection, and putative strain transmission events.

METHODS

An 18-month prospective study of recurrent CDI was undertaken. Clostridium difficile was cultured from stool samples collected longitudinally from any patients suffering ≥2 clinically defined CDI episodes. Patient demographics and clinical data were recorded, and strain relatedness investigated by both polymerase chain reaction (PCR)-based ribotyping and WGS.

FINDINGS

Nineteen patients were identified with ≥2 clinically defined CDI episodes who cumulatively suffered 39 recurring CDI episodes (58 total episodes). Patients had a median length of stay (LOS) of 144 days and experienced between two and seven CDI episodes. Ribotyping indicated 27 apparent same-strain relapses, five reinfections and the predominance of ribotypes 078 (ST-11) and 020 (ST-2). WGS allowed characterization of relapse with increased certainty and identified emergent within-strain single nucleotide variants (SNVs) with potential functional impact on diverse genes. Shared ribotypes among 14 patients with recurrent CDI suggested 10 possible patient-to-patient transmission events. However, WGS revealed greater diversity at the sub-ribotype level, excluding all but four transmission events.

CONCLUSION

WGS exhibits several advantages over PCR-based ribotyping in terms of its ability to distinguish relapse from reinfection, to identify patient-to-patient transmission events, and to exact fine structure characterization of recurrent CDI epidemiology. This offers the potential for more focused infection prevention strategies to eliminate strain transmission among patients with recurrent CDI.

Burden of Clostridium difficile infection in the United States

BACKGROUND

The magnitude and scope of Clostridium difficile infection in the United States continue to evolve.

METHODS

In 2011, we performed active population- and laboratory-based surveillance across 10 geographic areas in the United States to identify cases of C. difficile infection (stool specimens positive for C. difficile on either toxin or molecular assay in residents ≥ 1 year of age). Cases were classified as community-associated or health care-associated. In a sample of cases of C. difficile infection, specimens were cultured and isolates underwent molecular typing. We used regression models to calculate estimates of national incidence and total number of infections, first recurrences, and deaths within 30 days after the diagnosis of C. difficile infection.

RESULTS

A total of 15,461 cases of C. difficile infection were identified in the 10 geographic areas; 65.8% were health care-associated, but only 24.2% had onset during hospitalization. After adjustment for predictors of disease incidence, the estimated number of incident C. difficile infections in the United States was 453,000 (95% confidence interval [CI], 397,100 to 508,500). The incidence was estimated to be higher among females (rate ratio, 1.26; 95% CI, 1.25 to 1.27), whites (rate ratio, 1.72; 95% CI, 1.56 to 2.0), and persons 65 years of age or older (rate ratio, 8.65; 95% CI, 8.16 to 9.31). The estimated number of first recurrences of C. difficile infection was 83,000 (95% CI, 57,000 to 108,900), and the estimated number of deaths was 29,300 (95% CI, 16,500 to 42,100). The North American pulsed-field gel electrophoresis type 1 (NAP1) strain was more prevalent among health care-associated infections than among community-associated infections (30.7% vs. 18.8%, P<0.001).

CONCLUSIONS

C. difficile was responsible for almost half a million infections and was associated with approximately 29,000 deaths in 2011. (Funded by the Centers for Disease Control and Prevention.).

Single nucleotide polymorphisms of the tcdC gene and presence of the binary toxin gene predict recurrent episodes of Clostridium difficile infection

OBJECTIVE

To identify Clostridium difficile genotypes, which are associated with recurrent C difficile infection (RCDI).

BACKGROUND

Reliable bacterial genetic factors predicting RCDI are currently lacking.

METHODS

Inpatients and outpatients 18 years or older treated at our institution for C difficile infection (CDI) of any severity were consecutively enrolled. CDI was defined as symptoms of colitis with a positive PCR stool test. Each bacterial isolate was studied for virulence factors: tcdC mutations, including single nucleotide polymorphisms (SNPs) via PCR, the presence of genes for toxins A, B and binary toxin using restriction fragment length polymorphism, and identification of ribotype by PCR. χ tests, t tests, and logistic and linear regression were used to determine which virulence factors predicted RCDI and the need for hospital admission, with corrections made for multiple statistical comparisons.

RESULTS

Seventy-three patients (male: 52%; mean age: 66 ± 15 years) were studied. Binary toxin gene (P = 0.03) was associated with at least 1 episode of RCDI, as was the presence of SNPs C184T (P = 0.006) and A117T (P = 0.003). The presence of the binary toxin gene with either of these tcdC SNPs increased RCDI by 80% (P = 0.0002) but did not predict the need for hospital admission. None of the other virulence factors, including ribotype 027, were predictive of RCDI.

CONCLUSIONS

The presence of the binary toxin gene and tcdC SNPs C184T and A117T strongly predict RCDI. The presence of both tcdC SNPs and the binary toxin gene significantly increased the risk of RCDI, which might warrant longer antibiotic courses to eradicate the infection.

A prediction model for Clostridium difficile recurrence

Background

Clostridium difficile infection (CDI) is a growing problem in the community and hospital setting. Its incidence has been on the rise over the past two decades, and it is quickly becoming a major concern for the health care system. High rate of recurrence is one of the major hurdles in the successful treatment of C. difficile infection. There have been few studies that have looked at patterns of recurrence. The studies currently available have shown a number of risk factors associated with C. difficile recurrence (CDR); however, there is little consensus on the impact of most of the identified risk factors.

Methods

Our study was a retrospective chart review of 198 patients diagnosed with CDI via Polymerase Chain Reaction (PCR) from January 2009 to Jun 2013. In our study, we decided to use a machine learning algorithm called the Random Forest (RF) to analyze all of the factors proposed to be associated with CDR. This model is capable of making predictions based on a large number of variables, and has outperformed numerous other models and statistical methods.

Results

We came up with a model that was able to accurately predict the CDR with a sensitivity of 83.3%, specificity of 63.1%, and area under curve of 82.6%. Like other similar studies that have used the RF model, we also had very impressive results.

Conclusions

We hope that in the future, machine learning algorithms, such as the RF, will see a wider application.

Risk factors for recurrent Clostridium difficile infection: a systematic review and meta-analysis

OBJECTIVE

An estimated 20-30% of patients with primary Clostridium difficile infection (CDI) develop recurrent CDI (rCDI) within 2 weeks of completion of therapy. While the actual mechanism of recurrence remains unknown, a variety of risk factors have been suggested and studied. The aim of this systematic review and meta-analysis was to evaluate current evidence on the risk factors for rCDI.

DESIGN

We searched MEDLINE and 5 other databases for subject headings and text related to rCDI. All studies investigating risk factors of rCDI in a multivariate model were eligible. Information on study design, patient population, and assessed risk factors were collected. Data were combined using a random-effects model and pooled relative risk ratios (RRs) were calculated.

RESULTS

A total of 33 studies (n=18,530) met the inclusion criteria. The most frequent independent risk factors associated with rCDI were age≥65 years (risk ratio [RR], 1.63; 95% confidence interval [CI], 1.24-2.14; P=.0005), additional antibiotics during follow-up (RR, 1.76; 95% CI, 1.52-2.05; P<.00001), use of proton-pump inhibitors (PPIs) (RR, 1.58; 95% CI, 1.13-2.21; P=.008), and renal insufficiency (RR, 1.59; 95% CI, 1.14-2.23; P=.007). The risk was also greater in patients previously on fluoroquinolones (RR, 1.42; 95% CI, 1.28-1.57; P<.00001).

CONCLUSIONS

Multiple risk factors are associated with the development of rCDI. Identification of modifiable risk factors and judicious use of antibiotics and PPI can play an important role in the prevention of rCDI.

Predictors and outcomes of readmission for Clostridium difficile in a national sample of medicare beneficiaries

BACKGROUND

Rates of Clostridium difficile (CD) infections are increasing. Elderly patients may be at particular risk of recurrent CD infection. Little is known about the risk for CD readmission specifically in this age group.

METHODS

A 5% random sample of Medicare data (2009-2011) was queried for patients surviving a hospitalization for CD by ICD-9 code. Demographic (age, sex, gender), clinical (Elixhauser index, gastrointestinal comorbidities), and hospitalization (length of stay, ICU admission) characteristics as well as exposure to antibiotics and interim non-CD hospitalization were compared for those with and without a readmission for CD. A multivariable survival analysis was used to determine predictors of readmission.

RESULTS

Of 7,564 patients surviving a CD hospitalization, 8.5% were readmitted with CD in a median of 25 days (interquartile range (IQR) 14-57). In multivariable survival analyses, interim non-CD hospital exposure was the strongest predictor of CD readmission (hazard ration (HR) 3.75 95%, confidence interval (CI) 3.2-4.42). Oral and intravenous/intramuscular (IV/IM) antibiotic use, Elixhauser index, and CD as the primary diagnosis also increased the risk of CD readmission. Discharge to hospice, long-term care or a skilled nursing facility decreased the odds of CD readmission.

CONCLUSION

Hospital exposure and antibiotic use put elderly patients at risk of CD readmission. Exposure to these factors should be minimized in the immediate post discharge period.

Novel risk factors for recurrent Clostridium difficile infection in children

OBJECTIVES

Clostridium difficile, a common cause of antibiotic-associated diarrhea, has been reported to recur in high rates in adults. The rates and risk factors for recurrent C difficile infection (rCDI) in children have not been well established.

METHODS

We conducted a retrospective cohort study of 186 pediatric patients seen at a tertiary care referral center for a 5-year period diagnosed as having a primary C difficile infection. Children with recurrent disease, defined as return of symptoms of C difficile infection and positive testing ≤60 days after the completion of therapy, were compared with children who did not experience an episode of recurrence.

RESULTS

Of the 186 pediatric patients included in this study, 41 (22%) experienced rCDI. On univariable analysis, factors significantly associated with rCDI included malignancy, recent hospitalization, recent surgery, antibiotic use, number of antibiotic exposures by class, acid blocker use, immunosuppressant use, and hospital-acquired disease. On multivariable analysis, malignancy (odds ratio [OR] 3.39, 95% confidence interval [CI] 1.52-7.85), recent surgery (OR 2.40, 95% CI 1.05-5.52), and the number of antibiotic exposures by class (OR 1.33, 95% CI 1.01-1.75) were significantly associated with recurrent disease in children.

CONCLUSIONS

The rate of rCDI in children was 22%. Recurrence was significantly associated with the risk factors of malignancy, recent surgery, and the number of antibiotic exposures by class.

Clostridium difficile infection in the postcolectomy patient

Clostridium difficile infection (CDI) after total colectomy has been increasingly recognized over the past decade. C. difficile enteritis (CDE) is a rare occurrence, whereas C. difficile pouchitis (CDP) has been reported in approximately 10% of symptomatic patients seen at a referral center for pouch dysfunction. Similar to colonic CDI in the general population, antibiotic use and comorbid diseases may be risk factors for CDE. In contrast, the postoperative use of antibiotics does not seem to be associated with CDP, whereas male gender, recent hospitalization, and presurgery antibiotic use were shown to be risk factors for CDP. C. difficile is capable of colonizing all intestinal sites, including the ileal pouch. Similarities with the colon at physiological and cellular levels may contribute to the susceptibility of the ileal pouch to CDI. Postcolectomy CDI likely represents a disease spectrum from asymptomatic colonization to severe symptomatic infection. CDI should be considered in ostomy patients with fever and increased ileostomy output and in ileal pouch patients with a change in "normal" symptom pattern or chronic antibiotic-refractory pouchitis. Sensitive and specific methods for detection of CDI are available, and endoscopy is useful in evaluating the patient with suspected CDE or CDP, although pseudomembranes are typically absent. Vancomycin is used as the first-line therapy for CDP and may be warranted for patients with inflammatory bowel disease with CDE. Fecal microbiota transplantation has found its use in the management of severe or antibiotic refractory CDP, but this approach requires evaluation for the management of refractory CDE.

Risk factors and management of refractory or recurrent clostridium difficile infection in ileal pouch patients

BACKGROUND

Clostridium difficile infection (CDI) is increasingly recognized in patients with ulcerative colitis with ileal pouch-anal anastomosis (IPAA). The aim of this study was to identify clinical risk factors for treatment-refractory or recurrent CDI in patients with IPAA.

METHODS

We identified patients with IPAA for underlying ulcerative colitis and a positive polymerase chain reaction stool test for C. difficile at the Center for Ileal Pouch Disorders during the period from October 2010 to November 2013. Demographic clinical variables were compared between the refractory or recurrent CDI and nonrecurrent CDI groups.

RESULTS

Patients with IPAA with refractory or recurrent symptoms (refractory/recurrent CDI, the study group, N = 19) were compared with patients with a single antibiotic-responsive episode of ileal pouch CDI (nonrecurrent CDI, the control group, N = 21). The frequency of pouchitis before the index CDI was similar in the study and control groups (63.2% versus 66.7%, P = 0.82). Postoperative mechanical abnormalities occurred in 16 patients (84.2%) in the study group versus 7 patients (33.3%) in the control group (P = 0.0008). There were no differences between the two groups regarding hospitalization, non-C. difficile antibiotic use, the use of gastric acid-reducing therapy, or immunosuppressives before or after the index CDI. Six of 15 patients (40.0%) in the study group versus 1 of 15 patients (7.1%) in the control group had a low serum level of IgG1 (P = 0.031).

CONCLUSIONS

Refractory or recurrent disease is common in patients with ileal pouch with CDI. The presence of postsurgery mechanical intestinal complications or low serum immunoglobulin level may be risk factors for refractory or recurrent CDI in this patient population.

European Society of Clinical Microbiology and Infectious Diseases: update of the treatment guidance document for Clostridium difficile infection

In 2009 the first European Society of Clinical Microbiology and Infection (ESCMID) treatment guidance document for Clostridium difficile infection (CDI) was published. The guideline has been applied widely in clinical practice. In this document an update and review on the comparative effectiveness of the currently available treatment modalities of CDI is given, thereby providing evidence-based recommendations on this issue. A computerized literature search was carried out to investigate randomized and non-randomized trials investigating the effect of an intervention on the clinical outcome of CDI. The Grades of Recommendation Assessment, Development and Evaluation (GRADE) system was used to grade the strength of our recommendations and the quality of the evidence. The ESCMID and an international team of experts from 11 European countries supported the process. To improve clinical guidance in the treatment of CDI, recommendations are specified for various patient groups, e.g. initial non-severe disease, severe CDI, first recurrence or risk for recurrent disease, multiple recurrences and treatment of CDI when oral administration is not possible. Treatment options that are reviewed include: antibiotics, toxin-binding resins and polymers, immunotherapy, probiotics, and faecal or bacterial intestinal transplantation. Except for very mild CDI that is clearly induced by antibiotic usage antibiotic treatment is advised. The main antibiotics that are recommended are metronidazole, vancomycin and fidaxomicin. Faecal transplantation is strongly recommended for multiple recurrent CDI. In case of perforation of the colon and/or systemic inflammation and deteriorating clinical condition despite antibiotic therapy, total abdominal colectomy or diverting loop ileostomy combined with colonic lavage is recommended.

Serum mannose-binding lectin concentration, but not genotype, is associated with Clostridium difficile infection recurrence: a prospective cohort study

Low mannose-binding lectin concentration, but not genotype, was associated with disease recurrence in a large prospective cohort of patients with Clostridium difficile infection.

Background. Mannose-binding lectin (MBL) plays a key role in the activation of the lectin-complement pathway of innate immunity, and its deficiency has been linked with several acute infections. However, its role in predisposing to, or modulating disease severity in, Clostridium difficile infection (CDI) has not been investigated.

Methods. We prospectively recruited 308 CDI case patients and 145 control patients with antibiotic-associated diarrhea (AAD). CDI outcome measures were disease severity, duration of symptoms, 30-day mortality, and 90-day recurrence. Serum concentrations of MBL were determined using a commercial enzyme-linked immunosorbent assay transferred to an electrochemiluminescence–based platform. MBL2 polymorphisms were typed using a combination of pyrosequencing and TaqMan genotyping assays.

Results. The frequency of the MBL2 genetic variants was similar to that reported in other white populations. MBL serum concentrations in CDI and AAD subjects were determined by MBL2 exonic variants B, C, and D and the haplotypes (LYPB, LYQC, and HYPD). There was no difference in either MBL concentrations or genotypes between cases and controls. MBL concentration, but not genotype, was a determinant of CDI recurrence (odds ratios, 3.18 [95% confidence interval {CI}, 1.40–7.24] and 2.61 [95% CI, 1.35–5.04] at the <50 ng/mL and <100 ng/mL cutoff points, respectively; P < .001). However, neither MBL concentration nor MBL2 genotype was linked with the other CDI outcomes.

Conclusions. Serum MBL concentration did not differentiate between CDI cases and AAD controls, but among CDI cases, MBL concentration, but not genotype, was associated with CDI recurrence, indicating that MBL acts as a modulator of disease, rather than a predisposing factor.