Clostridium difficile infection in elderly nursing home residents

Consumer perspectives on antibiotic use in residential aged care: A mixed-methods systematic review

BACKGROUND

Aged care staff and doctors frequently highlight consumers' role in antibiotic treatment decisions. However, few studies include consumers. This study aimed to investigate consumer perspectives on antibiotic use in residential aged care.

METHODS

A search across 6 online databases yielded 3,373 studies, with 5 meeting inclusion criteria. Participant quotes, themes, statistical analyses, and authors' interpretive summaries in the included studies were inductively coded and refined to generate themes.

RESULTS

Three themes emerged: perception of benefits and risks of antibiotics, perceived role in antibiotic treatment decision-making, and information-communication needs. Consumers held positive attitudes toward antibiotics, did not associate antibiotics with the exclusive treatment of bacterial infections, and had limited awareness of potential risks, such as antibiotic resistance. Studies showed diverse perceptions regarding residents' and their families' involvement in antibiotic treatment decision-making with some residents actively seeking antibiotics and others trusting doctors to decide. Studies also described consumer need for effective provider-consumer communication and information sharing that was affected by contextual barriers such as motivation, preferences, available information resources, and provider attitudes.

CONCLUSIONS

Limited literature is available on consumer perspectives on antibiotic use in aged care. The review highlights that consumer needs are more complex than simply wanting an antibiotic. Antimicrobial stewardship programs should target consumer awareness, beliefs, and provider-consumer communication to enhance antibiotic use in aged care.

Risk factors for colonization with multidrug-resistant Gram-negative bacteria and Clostridioides difficile in Long Term Care Facilities (LTCFs) residents: the evidence from 27 facilities in a high endemic setting

Introduction

Residency in LTCFs increases the likelihood of colonization with multidrug resistant Gram-negative bacteria (MDR-GNB). We assessed the prevalence and risk factors for enteric colonization by III-generation cephalosporins-resistant and carbapenem-resistant (CR) GNB in a large group of LTCFs in a high endemic setting. We also assessed the prevalence and risk factors for C. difficile colonization.

Methods

A point prevalence survey with rectal screening (RS) was conducted in 27 LTCFs in north Italy. Epidemiological and clinical variables on the survey day, history of hospitalization and surgery within one year, and antibiotics within three months, were collected. The presence of III-generation cephalosporin resistant and CR GNB was assessed using a selective culture on chromogenic medium and PCR for carbapenemase detection. The presence of C. difficile was assessed using ELISA for GDH and RT-PCR to identify toxigenic strains. Multi-variable analyses were performed using two-level logistic regression models.

Results

In the study period 1947 RSs were performed. The prevalence of colonization by at least one GNB resistant to III-generation cephalosporin was 51% (E. coli 65%, K. pneumoniae 14% of isolates). The prevalence of colonization by CR GNB was 6%. 6% of all isolates (1150 strains) resulted in a carbapenem-resistant K. pneumoniae, and 3% in a carbapenem-resistant E. coli. KPC was the most frequent carbapenemase (73%) identified by PCR, followed by VIM (23%). The prevalence of colonization by C. difficile was 11.7%. The presence of a medical device (OR 2.67) and previous antibiotic use (OR 1.48) were significantly associated with III-generation cephalosporin resistant GNB colonization. The presence of a medical device (OR 2.67) and previous hospitalization (OR 1.80) were significantly associated with CR GNB. The presence of a medical device (OR 2.30) was significantly associated with C. difficile colonization. Main previously used antibiotic classes were fluoroquinolones (32% of previously treated subjects), III-generation cephalosporins (21%), and penicillins (19%).

Conclusion

Antimicrobial stewardship in LTCFs is a critical issue, being previous antibiotic treatment a risk factor for colonization by MDR-GNB. The prevalence of colonization by III-generation cephalosporin and CR GNB among LTCF residents also underlines the importance to adhere to hand hygiene indications, infection prevention and control measures, and environmental hygiene protocols, more achievable than rigorous contact precautions in this type of social setting.

Are antimicrobial stewardship interventions effective and safe in long-term care facilities? A systematic review and meta-analysis

BACKGROUND

Long-term care facilities (LTCFs) are health-care settings with high antimicrobial consumption and hence need to develop effective antimicrobial stewardship programmes (ASPs).

OBJECTIVE

To assess the effects of ASPs on care-related, clinical and ecological outcomes in LTCFs.

METHODS

Data sources were PubMed, EMBASE, CINAHL and SCOPUS. Study eligibility criteria were original research articles (controlled clinical trials or controlled before and after studies) published up to 1 October 2020. Participants were adult residents of LTCFs, residential aged-care facilities, nursing homes, veterans' homes, skilled nursing facilities and assisted living facilities for older people. Interventions included ASPs versus standard care. Outcomes assessed were antimicrobial consumption and appropriateness, infections, hospital admissions and mortality. Available data were pooled in a meta-analysis, and inconsistency between studies was evaluated using the I² statistic. Certainty of evidence was assessed using the GRADE approach.

RESULTS

Of the 3111 papers identified, 12 studies met the inclusion criteria. All of them analysed the impact of interventions on antimicrobial use based on consumption-related variables (n = 8) and/or percentage of inappropriate prescriptions (n = 6). Pooled data showed a mean difference of -0.47 prescriptions per 1000 resident-days in favour of ASPs (95% CI -0.87 to -0.07, I² = 71%). Five studies analysed the clinical effect of ASPs on the number of hospital admissions and/or resident mortality. The meta-analysis showed a mean difference of 0.17 hospital admissions per 1000 resident-days (95% CI -0.07 to 0.41, I² = 17%) and a mean difference of -0.02 deaths per 1000 resident-days (95% CI -0.14 to 0.09, I² = 0%). Only two studies included infections as a study outcome.

CONCLUSIONS

ASPs appear to improve antimicrobial use in this setting without increasing hospital admissions or deaths, indicating that these programmes do not lead to under-treatment of infections. Nonetheless, further higher-quality clinical trials are required to understand the effects of ASPs in LTCFs.

PROSPERO REGISTRATION NUMBER

CRD42021225127.

Prevalence and Risk Factors for Multidrug-Resistant Organisms Colonization in Long-Term Care Facilities Around the World: A Review

Elderly people confined to chronic care facilities face an increased risk of acquiring infections by multidrug-resistant organisms (MDROs). This review presents the current knowledge of the prevalence and risk factors for colonization by MDROs in long-term care facilities (LTCF), thereby providing a useful reference to establish objectives for implementing successful antimicrobial stewardship programs (ASPs). We searched in PubMed and Scopus for studies examining the prevalence of MDROs and/or risk factors for the acquisition of MDROs in LTCF. One hundred and thirty-four studies published from 1987 to 2020 were included. The prevalence of MDROs in LTCF varies between the different continents, where Asia reported the highest prevalence of extended-spectrum ß-lactamase (ESBL) Enterobacterales (71.6%), carbapenem resistant (CR) Enterobacterales (6.9%) and methicillin-resistant Staphylococcus aureus (MRSA) (25.6%) and North America the highest prevalence to MDR Pseudomonas aeruginosa (5.4%), MDR Acinetobacter baumannii (15.0%), vancomycin-resistant Enterococcus spp. (VRE) (4.0%), and Clostridioides difficile (26.1%). Furthermore, MDRO prevalence has experienced changes over time, with increases in MDR P. aeruginosa and extended spectrum ß-lactamase producing Enterobacterales observed starting in 2015 and decreases of CR Enterobacterales, MDR A. baumannii, VRE, MRSA and C. difficile. Several risk factors have been found, such as male sex, chronic wounds, the use of medical devices, and previous antibiotic use. The last of these aspects represents one of the most important modifiable factors for reducing colonization with MDROs through implementing ASPs in LTCF.

Investigation of Clostridium difficile in elderly people: A preliminary study in Iran

Elderly people are at increased risk for infections such as with Clostridium difficile. This can colonize their gut and cause various gastro-intestinal manifestations. Our survey investigated its prevalence in a nursing home in Iran. Faecal samples were collected and tested by polymerase chain reaction for identification of A, B and binary toxin genes. From 289 samples, 42(14.5%) isolates were found. Toxin genes were positive in 19 isolates (17 AþBþ and 2 isolates ABþ). The elderly are especially at risk and great attention should be paid to contamination within their nursing homes. This is not an isolated regional problem.

Health care resource utilization and costs of recurrent Clostridioides difficile infection in the elderly: a real-world claims analysis

BACKGROUND: Clostridioides difficile infection (CDI) affected an estimated 365,000 persons in the United States in 2017. Despite a nationally decreasing trend of CDI cases, the population incidence of recurrent CDI (rCDI) has not improved. Elderly individuals (aged ≥ 65 years) are at higher risk of CDI, rCDI, and complicated CDI compared with younger individuals. OBJECTIVE: To analyze Medicare fee-for-service data for 12 months after an initial CDI episode, in order to obtain real-world data on health care resource utilization (HRU) and costs for elderly patients with CDI and rCDI. METHODS: A retrospective cohort study of patients who were aged ≥ 65 years and had a first (index) CDI diagnosis from January 1, 2010, to December 31, 2016, and continuous enrollment in Medicare Parts A, B, and D during the 12-month pre-index and 12-month post-index periods was conducted. A CDI episode was identified by either an inpatient stay with CDI diagnosis code or an outpatient medical claim with a CDI diagnosis code plus a CDI treatment. Each CDI episode was followed by a 14-day CDI claim-free period after the last CDI claim or end of CDI treatment. rCDI was a second or subsequent episode of CDI that occurred within an 8-week window after the 14-day CDI claim-free period. The number of CDI and rCDI episodes, HRU, time to recurrence, and total all-cause direct medical costs were calculated over the 12-month pre-index (baseline) and 12-month follow-up periods and stratified by number of rCDI episodes (No rCDI, 1 rCDI, 2 rCDI, 3+ rCDI). RESULTS: A total of 268,762 patients with an index CDI were included. Mean age was 78.3 years, and 69.0% were female. HRU was higher during the 6 months immediately pre-index versus 7-12 months pre-index, including a higher proportion of patients with a hospital admission (55.1% vs. 27.5%) or emergency department visit (41.3% vs. 27.4%), respectively. Moreover, 34.7% of the study population experienced rCDI. Of those who experienced 1 recurrence, 59.1% had a second recurrence, and of those who had 2 recurrences, 58.4% had a third. During the 12-month follow-up, postacute care was used by at least 70% of each rCDI cohort. The proportion of patients with ≥ 4 hospital admissions during follow-up was highest for the 3+ rCDI cohort (24.9% of patients). During the 12-month follow-up, mean total all-cause direct costs were $76,024, $99,348, $96,148, and $96,517 for the No rCDI, 1 rCDI, 2 rCDI, and 3+ rCDI cohorts, respectively, largely driven by inpatient costs. Adjusted all-cause total costs were significantly higher for all 3 rCDI cohorts compared with the No rCDI cohort. CONCLUSIONS: Elderly individuals experienced high rates of recurrence after their first CDI episode, and especially after a prior recurrence. The intensity of HRU during follow-up was higher for patients who suffered recurrences. Patients with rCDI had the burden of higher costs of care, including the patient out-of-pocket responsibility, versus patients with a single CDI episode. DISCLOSURES: Funding for this study was provided by Ferring Pharmaceuticals. Nelson is an employee of Ferring Pharmaceuticals, and Scott, Boules, and Unni were employees of Ferring Pharmaceuticals at the time of this study. Teigland and Parente are employees of Avalere Health and provided consulting services to Ferring Pharmaceuticals. Feuerstadt has served as a consultant to and on the speakers bureau for Merck and Co. and has served as a consultant for Ferring Pharmaceuticals and Roche Pharmaceuticals. Portions of the data contained in this study appeared as an abstract/ePoster for the AMCP Annual Meeting 2020, April 2020.

Current status of proton pump inhibitor use in Japanese elderly patients with non-valvular atrial fibrillation: A subanalysis of the ANAFIE Registry

The real-world status of proton pump inhibitor (PPI) use in patients with atrial fibrillation (AF) receiving antithrombotic treatment is largely unknown. The All Nippon AF In the Elderly (ANAFIE) Registry, a prospective, multicenter, observational study, aimed to determine treatment patterns, risk factors, and outcomes among elderly (aged ≥75 years) Japanese non-valvular AF (NVAF) patients in the real-world clinical setting. The present subanalysis of the ANAFIE Registry determined the PPI prescription status of 32,490 elderly Japanese NVAF patients. Patients were stratified by PPI use (PPI+) or no PPI use (PPI−). Risk scores for stroke (CHADS₂, CHA₂DS₂-VASc) and bleeding (HAS-BLED), anticoagulant use, time in therapeutic range (TTR) for warfarin, and anticoagulant/antiplatelet combination use were evaluated. PPIs were used in 11,981 (36.9%) patients. Compared with the PPI− group, the PPI+ group included a greater proportion of female patients (45.2% vs 41.3%; P <0.0001) and had significantly higher CHADS₂, CHA₂DS₂-VASc, and HAS-BLED scores (P <0.0001 for each) as well as higher prevalences of several comorbidities. In the PPI+ group, 54.6% of patients did not have gastrointestinal (GI) disorders and were likely prescribed a PPI to prevent GI bleeding events. Most of the patients with a GI disorder in the PPI+ group had reflux esophagitis. Compared with patients not receiving anticoagulants, a significantly higher proportion of patients receiving anticoagulants received PPIs. For patients receiving anticoagulants, antiplatelet drugs, and both drugs, rates of PPI use were 34.1%, 44.1%, and 53.5%, respectively (P <0.01). Although the rate of PPI use was the highest for NVAF patients receiving both antiplatelet and anticoagulants, no clear differences were observed in the anticoagulants used. These data suggest that PPIs were actively prescribed in high-risk cases and may have been used to prevent GI bleeding among elderly NVAF patients receiving antithrombotic drugs.

Trial registration:UMIN000024006

Multidrug-resistant infections in long-term care facilities: extended-spectrum β-lactamase-producing Enterobacteriaceae and hypervirulent antibiotic resistant Clostridium difficile

Infections due to multidrug-resistant (MDR) organisms in long-term care facilities (LTCFs) residents constitute a public health concern. This multicenter study investigated the frequency of ESBL-producing pathogens and MDR Clostridium difficile in clinical specimens from LTCF residents in Italy. During October 2014-March 2015, all urine and diarrheic fecal samples from LTCF residents (≥65 years) with suspected urinary tract infection or C. difficile infection, respectively, received for diagnosis by 4 hospital laboratories located in different cities were analyzed. Antibiotic susceptibility testing, characterization of resistance genes, and molecular typing of pathogens were performed. Of 806 urine cultures collected from 626 residents at 44 different LTCFs, 492 were positive for microbial infection. Of these, 158 were positive for at least an ESBL-producing Enterobacteriaceae species (32.1%), with Escherichia coli as the most frequent ESBL pathogen (23.4%) followed by Klebsiella pneumoniae (4.5%). Furthermore, 4 carbapenemase producers (0.8%) (1 E. coli with VIM-1and 3 K. pneumoniae with KPC-3) were detected. The CTX-M-15 type ESBL predominated in both E. coli (71.3%) and K. pneumoniae (77.3%). Most E. coli isolates (82.6%) belonged to the ST131/H30 clone/subclone. For K. pneumoniae, ST307 and ST15 were frequent (31.8% and 22.7%, respectively), but isolates harboring bla_KPC-3 belonged to CC258. Of 136 diarrheic fecal samples collected from 111 residents at 26 different LTCFs, 21 (15.4%) were positive for toxigenic C. difficile; of these, 13 (62%) were MDR (resistant to 3 or more antimicrobial agents of different classes). The predominant C. difficile polymerase chain reaction ribotype was 356/607 (42.9%), followed by 018, 449, and 078 (14% each). Public health efforts are needed to contain the diffusion of CTX-M-producing Enterobacteriaceae and MDR C. difficile in LTCF settings.

Evaluating the Sporicidal Activity of Disinfectants against Clostridium difficile and Bacillus amyloliquefaciens Spores by Using the Improved Methods Based on ASTM E2197-11

Spore-forming pathogenic bacteria, such as Clostridium difficile, are associated with nosocomial infection, leading to the increased use of sporicidal disinfectants, which impacts socioeconomic costs. However, C. difficile can be prevented using microorganisms such as Bacillus amyloliquefaciens, a prophylactic agent that has been proven to be effective against it in recent tests or it can be controlled by sporicidal disinfectants. These disinfectants against spores should be evaluated according to a known and recommended standard. Unfortunately, some newly manufactured disinfectants like Bioxy products have not yet been tested. ASTM E2197-11 is a standard test that uses stainless steel disks (1 cm in diameter) as carriers, and the performance of the test formulation is calculated by comparing the number of viable test organisms to that on the control carriers. Surface tests are preferable for evaluating disinfectants with sporicidal effects on hard surfaces. This study applies improved methods, based on the ASTM E2197-11 standard, for evaluating and comparing the sporicidal efficacies of several disinfectants against spores of C. difficile and B. amyloliquefaciens, which are used as the test organisms. With the improved method, all spores were recovered through vortexing and membrane filtration. The results show that chlorine-based products are effective in 5 min and Bioxy products at 5% w/v are effective in 10 min. Although Bioxy products may take longer to prove their effectiveness, their non-harmful effects to hospital surfaces and people have been well established in the literature.

Acid-Suppressive Therapy and Risk of Infections: Pros and Cons

This narrative review summarises the benefits, risks and appropriate use of acid-suppressing drugs (ASDs), proton pump inhibitors and histamine-2 receptor antagonists, advocating a rationale balanced and individualised approach aimed to minimise any serious adverse consequences. It focuses on current controversies on the potential of ASDs to contribute to infections-bacterial, parasitic, fungal, protozoan and viral, particularly in the elderly, comprehensively and critically discusses the growing body of observational literature linking ASD use to a variety of enteric, respiratory, skin and systemic infectious diseases and complications (Clostridium difficile diarrhoea, pneumonia, spontaneous bacterial peritonitis, septicaemia and other). The proposed pathogenic mechanisms of ASD-associated infections (related and unrelated to the inhibition of gastric acid secretion, alterations of the gut microbiome and immunity), and drug-drug interactions are also described. Both probiotics use and correcting vitamin D status may have a significant protective effect decreasing the incidence of ASD-associated infections, especially in the elderly. Despite the limitations of the existing data, the importance of individualised therapy and caution in long-term ASD use considering the balance of benefits and potential harms, factors that may predispose to and actions that may prevent/attenuate adverse effects is evident. A six-step practical algorithm for ASD therapy based on the best available evidence is presented.

Recurrent Clostridium difficile infection among Medicare patients in nursing homes: A population-based cohort study

We explored the epidemiology and outcomes of Clostridium difficile infection (CDI) recurrence among Medicare patients in a nursing home (NH) whose CDI originated in acute care hospitals.We conducted a retrospective, population-based matched cohort combining Medicare claims with Minimum Data Set 3.0, including all hospitalized patients age ≥65 years transferred to an NH after hospitalization with CDI 1/2011-11/2012. Incident CDI was defined as ICD-9-CM code 008.45 with no others in prior 60 days. CDI recurrence was defined as (within 60 days of last day of CDI treatment): oral metronidazole, oral vancomycin, or fidaxomicin for ≥3 days in part D file; or an ICD-9-CM code for CDI (008.45) during a rehospitalization. Cox proportional hazards and linear models, adjusted for age, gender, race, and comorbidities, examined mortality within 60 days and excess hospital days and costs, in patients with recurrent CDI compared to those without.Among 14,472 survivors of index CDI hospitalization discharged to an NH, 4775 suffered a recurrence. Demographics and clinical characteristics at baseline were similar, as was the risk of death (24.2% with vs 24.4% without). Median number of hospitalizations was 2 (IQR 1-3) among those with and 0 (IQR 0-1) among those without recurrence. Adjusted excess hospital days per patient were 20.3 (95% CI 19.1-21.4) and Medicare reimbursements $12,043 (95% CI $11,469-$12,617) in the group with a recurrence.Although recurrent CDI did not increase the risk of death, it was associated with a far higher risk of rehospitalization, excess hospital days, and costs to Medicare.

Fecal Microbiota Transplantation for Recurrent Clostridium difficile Infection in the Elderly: Long-Term Outcomes and Microbiota Changes

BACKGROUND AND AIMS

Fecal microbiota transplantation (FMT) has become the cornerstone in management of recurrent Clostridium difficile infection (RCDI) in adults. However, data on efficacy, safety, long-term outcomes, and microbiota alterations are limited in elderly patients (>65 years).

METHODS

Twenty-nine consecutive elderly patients with RCDI underwent FMT with combined jejunal and colonic method and monitored for long-term outcomes. Fecal samples from five elderly RCDI patients (G65) were subjected to genomic analysis before and after FMT, and microbiota changes were compared with matched RCDI patients below 65 years (L65).

RESULTS

FMT resulted in marked improvement in all clinical parameters, including abdominal pain, bloating, and diarrhea in all elderly RCDI patients. Fecal C. difficile toxin was positive in all 29 patients and turned negative in all 27 patients, who agreed to undergo this test after FMT. Statistically significant improvement in leukocytosis was noted (p < 0.05). Only adverse events reported were transient mild fever (2/29) and bloating (3/29). Long-term follow-up over 25.4 ± 12.8 months did not reveal any additional adverse events or RCDI recurrence. Genomic analysis suggested that overall microbiota diversity increased post-FMT in elderly RCDI patients. However, this response was less robust than the younger group. While Firmicutes did not change markedly, Proteobacteria decreased significantly in post-FMT samples in elderly RCDI patients.

CONCLUSIONS

These observations suggest that FMT in elderly patients with RCDI appears to be highly efficacious with no recurrence of infection over long-term follow-up. Alterations in microbiota in this group of patients are characterized by less robust increase in microbial diversity and marked reduction in phylum Proteobacteria.

Longitudinal survey of Clostridium difficile presence and gut microbiota composition in a Belgian nursing home

BACKGROUND

Increasing age, several co-morbidities, environmental contamination, antibiotic exposure and other intestinal perturbations appear to be the greatest risk factors for C. difficile infection (CDI). Therefore, elderly care home residents are considered particularly vulnerable to the infection. The main objective of this study was to evaluate and follow the prevalence of C. difficile in 23 elderly care home residents weekly during a 4-month period. A C. difficile microbiological detection scheme was performed along with an overall microbial biodiversity study of the faeces content by 16S rRNA gene analysis.

RESULTS

Seven out of 23 (30.4 %) residents were (at least one week) positive for C. difficile. C. difficile was detected in 14 out of 30 diarrhoeal samples (43.7 %). The most common PCR-ribotype identified was 027. MLVA showed that there was a clonal dissemination of C. difficile strains within the nursing home residents. 16S-profiling analyses revealed that each resident has his own bacterial imprint, which was stable during the entire study. Significant changes were observed in C. difficile positive individuals in the relative abundance of a few bacterial populations, including Lachnospiraceae and Verrucomicrobiaceae. A decrease of Akkermansia in positive subjects to the bacterium was repeatedly found.

CONCLUSIONS

A high C. difficile colonisation in nursing home residents was found, with a predominance of the hypervirulent PCR-ribotype 027. Positive C. difficile status is not associated with microbiota richness or biodiversity reduction in this study. The link between Akkermansia, gut inflammation and C. difficile colonisation merits further investigations.

Enhanced surveillance of Clostridium difficile infection occurring outside hospital, England, 2011 to 2013

There are limited national epidemiological data for community-associated (CA)-Clostridium difficile infections (CDIs). Between March 2011 and March 2013, laboratories in England submitted to the Clostridium difficile Ribotyping Network (CDRN) up to 10 diarrhoeal faecal samples from successive patients with CA-CDI, defined here as C. difficile toxin-positive diarrhoea commencing outside hospital (or less than 48 hours after hospital admission), including those cases associated with community-based residential care, with no discharge from hospital within the previous 12 weeks. Patient demographics and C. difficile PCR ribotypes were compared for CA-CDIs in our study and presumed healthcare-associated (HA) CDIs via CDRN. Ribotype diversity indices, ranking and relative prevalences were very similar in CA- vs HA-CDIs, although ribotypes 002 (p ≤ 0.0001),020 (p = 0.009) and 056 (p < 0.0001) predominated in CA-CDIs; ribotype 027 (p = 0.01) predominated in HA-CDIs. Epidemic ribotypes 027 and 078 predominated in institutional residents with CDI (including care/nursing homes) compared with people with CDI living at home. Ribotype diversity decreased with increasing age in HA-CDIs, but not in CA-CDIs. Ribotype 078 CA-CDIs were significantly more common in elderly people (3.4% (6/174) vs 8.7% (45/519) in those aged < 65 and ≥ 65 years, respectively; p = 0.019). No antibiotics were prescribed in the previous four weeks in about twofold more CA-CDI vs HAs (38.6% (129/334) vs 20.3% (1,226/6,028); p < 0.0001). We found very similar ribotype distributions in CA- and HA-CDIs, although a few ribotypes significantly predominated in one setting. These national data emphasise the close interplay between, and likely common reservoirs for, CDIs, particularly when epidemic strains are not dominant.

Isolation of C. difficile Carriers Alone and as Part of a Bundle Approach for the Prevention of Clostridium difficile Infection (CDI): A Mathematical Model Based on Clinical Study Data

Clostridium difficile infection is the most common hospital-acquired infection. Besides infected patients, carriers have emerged as a key player in C. difficile epidemiology. In this study, we evaluated the impact of identifying and isolating carriers upon hospital admission on the incidence of CDI incidence and hospital-acquired C. difficile colonization, as a single policy and as part of bundle approaches. We simulated C. difficile transmission using a stochastic mathematical approach, considering the contribution of carriers based on published literature. In the baseline scenario, CDI incidence was 6.18/1,000 admissions (95% CI, 5.72–6.65), simulating reported estimates from U.S. hospital discharges. The acquisition rate of C. difficile carriage was 9.72/1,000 admissions (95% CI, 9.15–10.31). Screening and isolation of colonized patients on admission to the hospital decreased CDI incidence to 4.99/1,000 admissions (95% CI, 4.59–5.42; relative reduction (RR) = 19.1%) and led to 36.2% reduction in the rate of hospital-acquired colonization. Simulating an antimicrobial stewardship program reduced CDI rate to 2.35/1,000 admissions (95% CI, 2.07–2.65). In sensitivity analysis, CDI incidence was less than 2.32/1,000 admissions (RR = 62.4%) in 95% of 1,000 simulations. The combined bundle, focusing on reducing C. difficile transmission from colonized patients and the individual risk of these patients to develop CDI, decreased significantly the incidence of both CDI and hospital-acquired colonization. Implementation of this bundle to current practice is expected to have an important impact in containing CDI.

Clostridium difficile infection: Early history, diagnosis and molecular strain typing methods

Recognised as the leading cause of nosocomial antibiotic-associated diarrhoea, the incidence of Clostridium difficile infection (CDI) remains high despite efforts to improve prevention and reduce the spread of the bacterium in healthcare settings. In the last decade, many studies have focused on the epidemiology and rapid diagnosis of CDI. In addition, different typing methods have been developed for epidemiological studies. This review explores the history of C. difficile and the current scope of the infection. The variety of available laboratory tests for CDI diagnosis and strain typing methods are also examined.

A Diagnostic Algorithm for the Detection of Clostridium difficile-Associated Diarrhea

BACKGROUND

Clostridium difficile is a common cause of hospital-acquired diarrhea, which is usually associated with previous antibiotic use. The clinical manifestations of C. difficile infection (CDI) may range from mild diarrhea to fulminant colitis. Clostridium difficile should be considered in diarrhea cases with a history of antibiotic use within the last 8 weeks (community-associated CDI) or with a hospital stay of at least 3 days, regardless of the duration of antibiotic use (hospital-acquired CDI).

AIMS

This study investigated the frequency of CDI in diarrheic patients and evaluated the efficacy of the triple diagnostic algorithm that is proposed here for C. difficile detection.

STUDY DESIGN

Cross-sectional study.

METHODS

In this study, we compared three methods currently employed for C. difficile detection using 95 patient stool samples: an enzyme immunoassay (EIA) for toxin A/B (C. diff Toxin A+B; Diagnostic Automation Inc.; Calabasas, CA, USA), an EIA for glutamate dehydrogenase (GDH) (C. DIFF CHEK-60TM, TechLab Inc.; Blacksburg, VA, USA), and a polymerase chain reaction (PCR)-based assay (GeneXpert(®) C. difficile; Cepheid, Sunnyvale, CA, USA) that detects C. difficile toxin genes and conventional methods as well. In this study, 50.5% of the patients were male, 50 patients were outpatients, 32 were from inpatient clinics and 13 patients were from the intensive care unit.

RESULTS

Of the 95 stool samples tested for GDH, 28 were positive. Six samples were positive by PCR, while nine samples were positive for toxin A/B. The hypervirulent strain NAP-1 and binary toxin was not detected. The rate of occurrence of toxigenic C. difficile was 5.1% in the samples. Cefaclor, ampicillin-sulbactam, ertapenem, and piperacillin-tazobactam were the most commonly used antibiotics by patients preceding the onset of diarrhea. Among the patients who were hospitalized in an intensive care unit for more than 7 days, 83.3% were positive for CDI by PCR screening. If the PCR test is accepted as the reference: C. difficile Toxin A/B ELISA sensitivity and specificity were 67% and 94%, respectively, and GDH sensitivity and specificity were 100% and 75%, respectively.

CONCLUSION

Tests targeting C. difficile toxins are frequently applied for the purpose of diagnosing CDI in a clinical setting. However, changes in the temperature and reductant composition of the feces may affect toxin stability, potentially yielding false-negative test results. Therefore, employment of a GDH EIA, which has high sensitivity, as a screening test for the detection of toxigenic strains, may prevent false-negative results, and its adoption as part of a multistep diagnostic algorithm may increase accuracy in the diagnosis of CDIs.

What's the Clinical Features of Colitis in Elderly People in Long-Term Care Facilities?

BACKGROUND/AIMS

As life expectancy has increased, the number of elderly patients who need long-term care has grown rapidly. Mortality in patients with colitis in long-term care facilities (LTCFs) is increasing. We intend to investigate the main causes of colitis in LTCFs compared to those of colitis in local communities, and to identify the clinical features and risk factors of patients with colitis in LTCFs.

METHODS

We retrospectively analyzed epidemiology, medical conditions, laboratory values, diagnoses, and clinical courses of elderly patients aged ≥65 who were admitted to the Ewha Womans University hospital with colitis between January 2007 and July 2012.

RESULTS

Patients with colitis in LTCFs (n=20) were compared with elderly patients with colitis in local communities (n=154). Fifty-five percent of colitis in LTCFs was caused by Clostridium difficile infection (CDI), 30% was due to ischemic colitis, and 15% was due to non-specific colitis. Non-specific colitis was the most common (63%) in the community group. Clinical outcomes were also significantly different between both groups: higher mortality (10.0% vs. 0.64%, P=0.021), higher requirement for intensive care units care (50.0% vs. 18.8%, P<0.01) in LTCFs group. In univariate analysis, the most significant risk factor for death in patients in LTCFs was decreased mental faculties.

CONCLUSIONS

Patients in LTCFs showed worse clinical outcomes and a much higher prevalence of CDI compared to patients from local communities. We suggest early and active evaluation, such as endoscopic examination, for differential diagnosis in patients in LTCFs.