Clostridium difficile-associated diarrhea outbreaks: the name of the game is isolation and cleaning

Infection prevention and control practices related to Clostridium difficile infection in Canadian acute and long-term care institutions

BACKGROUND

Clostridium difficile is an important pathogen in Canadian health care facilities, and infection prevention and control (IPC) practices are crucial to reducing C difficile infections (CDIs). We performed a cross-sectional study to identify CDI-related IPC practices in Canadian health care facilities.

METHODS

A survey assessing facility characteristics, CDI testing strategies, CDI contact precautions, and antimicrobial stewardship programs was sent to Canadian health care facilities in February 2005.

RESULTS

Responses were received from 943 (33%) facilities. Acute care facilities were more likely than long-term care (P < .001) and mixed care facilities (P = .03) to submit liquid stools from all patients for CDI testing. Physician orders were required before testing for CDI in 394 long-term care facilities (66%)-significantly higher than the proportions in acute care (41%; P < .001) and mixed care sites (49%; P < .001). A total of 841 sites (93%) had an infection control manual, 639 (76%) of which contained CDI-specific guidelines. Antimicrobial stewardship programs were reported by 40 (29%) acute care facilities; 19 (54%) of these sites reported full enforcement of the program.

CONCLUSION

Canadian health care facilities have widely varying C difficile IPC practices. Opportunities exist for facilities to take a more active role in IPC policy development and implementation, as well as antimicrobial stewardship.

The changing epidemiology of Clostridium difficile infections

The epidemiology of Clostridium difficile infection (CDI) has changed dramatically during this millennium. Infection rates have increased markedly in most countries with detailed surveillance data. There have been clear changes in the clinical presentation, response to treatment, and outcome of CDI. These changes have been driven to a major degree by the emergence and epidemic spread of a novel strain, known as PCR ribotype 027 (sometimes referred to as BI/NAP1/027). We review the evidence for the changing epidemiology, clinical virulence and outcome of treatment of CDI, and the similarities and differences between data from various countries and continents. Community-acquired CDI has also emerged, although the evidence for this as a distinct new entity is less clear. There are new data on the etiology of and potential risk factors for CDI; controversial issues include specific antimicrobial agents, gastric acid suppressants, potential animal and food sources of C. difficile, and the effect of the use of alcohol-based hand hygiene agents.

The changing epidemiology of Clostridium difficile infections

The epidemiology of Clostridium difficile infection (CDI) has changed dramatically during this millennium. Infection rates have increased markedly in most countries with detailed surveillance data. There have been clear changes in the clinical presentation, response to treatment, and outcome of CDI. These changes have been driven to a major degree by the emergence and epidemic spread of a novel strain, known as PCR ribotype 027 (sometimes referred to as BI/NAP1/027). We review the evidence for the changing epidemiology, clinical virulence and outcome of treatment of CDI, and the similarities and differences between data from various countries and continents. Community-acquired CDI has also emerged, although the evidence for this as a distinct new entity is less clear. There are new data on the etiology of and potential risk factors for CDI; controversial issues include specific antimicrobial agents, gastric acid suppressants, potential animal and food sources of C. difficile, and the effect of the use of alcohol-based hand hygiene agents.

Reducing Clostridium difficile through early identification of clusters and the use of a standardised set of interventions

In recent years the rates of Clostridium difficile infection (CDI) have increased worldwide with several large outbreaks occurring within the UK. New guidance from the UK Department of Health describes measures to investigate periods of increased incidence (PII) of CDI which include informing staff, ribotyping isolates, enhanced cleaning, audits and monitoring of antibiotic prescribing. This study aimed to determine whether a standardised set of measures could be used to control the incidence of CDI within an acute hospital setting over an 18 month period. During the study period a total of 102 PII involving 439 patients were investigated. The number of PII per month ranged from 14 in February 2008 to one in June 2009. From January 2008 to September 2008, ribotyping of patient isolates was only carried out on PII involving more than 10 patients, but from October 2008 it was carried out on all PII. During the period October 2008 to June 2009, 28 PII were investigated on 21 different wards, with seven wards having two PII. Ribotyping of the isolates confirmed nine (32%) of these PII to be outbreaks, with three being due to ribotype 027, two ribotype 078 and the others distinct ribotypes. Use of a set of standardised interventions has resulted in a decrease in the incidence of PII and a reduction in the number of patients involved. By taking early action with a set of standardised measures the incidence of hospital-acquired CDI can be reduced.

Multipronged intervention strategy to control an outbreak of Clostridium difficile infection (CDI) and its impact on the rates of CDI from 2002 to 2007

OBJECTIVE

At the end of 2002, a new, more virulent strain of Clostridium difficile, designated BI/NAP1, was the cause of a massive outbreak of infection in the province of Quebec. This particular strain was associated with a dramatic increase in morbidity and mortality among affected patients in 2003-2004. We tested and implemented a multipronged infection control approach to curtail the rate of C. difficile infection (CDI).

DESIGN

Five-year observational study.

SETTING

A 554-bed, acute care tertiary hospital, the largest single medical center in Quebec, Canada.

METHODS

To curtail the magnitude of the outbreak, we implemented a global strategy consisting of rapid C. difficile testing for all hospitalized patients who had at least 1 occurrence of liquid stool, the rapid isolation of patients infected with C. difficile in a dedicated ward with a specially trained housekeeping team, a global hand hygiene program, and the hiring of infection control practitioners. Antibiotic consumption at the institutional level was also monitored during the 5-year surveillance period. Cases of hospital-acquired CDI per 1,000 admissions were continuously monitored on a monthly basis during the entire surveillance period.

RESULTS

The highest recorded CDI rate was 42 cases per 1,000 admissions in January 2004. Once additional infection control resources were put in place, the rate decreased significantly during the period from April 2005 to March 2007. During the 2003-2004 period, there were 762 cases of CDI (mean annual rate, 37.28 cases per 1,000 admissions) recorded in our study, compared with 292 cases of CDI (14.48 cases per 1,000 admissions) during the 2006-2007 period (OR, 0.379 [95% CI, 0.331-0.435]; p< .001), a 61% reduction. In March 2007, the equivalent of 4 full-time equivalent infection control practitioners were in place, which gave a ratio of 0.96 infection control practitioners per 133 beds in use, compared with the ratio of 0.24 infection control practitioners per 133 beds in use in 2003, and the total number of hours dedicated to cleaning and housekeeping increased by 26.2%. The total amount of antibiotics used in the hospital did not vary significantly from 2002 to 2007, although there were changes in the classes antibiotic used.

CONCLUSION

The implementation of a multipronged intervention strategy to control the outbreak of CDI significantly improved the overall situation at the hospital and underlined the importance of investing in stringent infection control practices.

Infection control practices related to Clostridium difficile infection in acute care hospitals in Canada

BACKGROUND

We carried out a survey to identify the infection prevention and control practices in place in Canadian hospitals participating in the Canadian Nosocomial Infection Surveillance Program (CNISP).

METHODS

An infection prevention and control practices survey was sent to CNISP hospitals at the beginning of November 2004, the same time that CNISP started a 6-month prospective surveillance for Clostridium difficile infection (CDI) to evaluate their infection prevention and control measures and laboratory methods for C difficile.

RESULTS

A total of 33 hospitals completed and returned the survey. Infection control precautions were initiated in 18 hospitals (55%) due to the presence of a symptomatic patient before the C difficile laboratory tests were available. All of the hospitals used gloves and gowns as additional precautions. Twenty-three hospitals (70%) tested liquid stools based on a clinician's order, and 8 (24%) tested all liquid stools submitted whether of not C difficile testing was requested. The hospitals used 1 of 3 different products as a standard hospital-wide disinfectant; 24 (73%) used a quaternary ammonium compound, 8 (24%) used accelerated hydrogen peroxide, and 1 (3%) used a hypochlorite solution (1:10 bleach solution).

CONCLUSION

Although the hospitals used contact precautions quite uniformly, considerable variation was seen among hospitals in terms of testing strategies, cleaning and disinfection protocols and products, and isolation practices. The timing for the initiation of infection control precautions is important to prevent secondary transmission of CDI. Most of the hospitals implemented precautions while waiting for the toxin assay results.

Toxin-binding treatment for Clostridium difficile: a review including reports of studies with tolevamer

Clostridium difficile represents an increasing threat to patients, mainly as a hospital-acquired infection causing antibiotic-associated colitis (AAC). The emergence of a new more virulent strain in North America and Europe has been linked to increased morbidity and mortality. For a long period of time the only available therapeutic options were oral vancomycin and metronidazole. However, both of these antibiotics have limitations either in terms of efficacy, cost, formulation, side effects or the risk of emerging antibiotic resistance among enterococci. Clostridium difficile produces two powerful toxins (A and B) that are responsible for the entire clinical spectrum associated with AAC. As this is exclusively a toxin-mediated disease, agents with the potential of binding these targets have been tested. Data on polymer-based toxin-binding agents such as cholestyramine, Synsorb 90 and tolevamer, designed to target specific bacterial toxins, will be reviewed. Bovine colostrum and specific human monoclonal antibodies aimed at neutralising toxin A, although still at an early stage of development, are also new avenues to be explored. Non-antibiotic-based therapies might become the best available option for a condition almost always caused by antibiotics.

Clinical severity of Clostridium difficile PCR ribotype 027: a case-case study

BACKGROUND

Clostridium difficile is a leading infectious cause of health care associated diarrhoea. Several industrialised countries have reported increased C. difficile infections and outbreaks, which have been attributed to the emergent PCR ribotype 027 strain.

METHODS AND FINDINGS

We conducted a case-case study to compare severity of C. difficile disease for patients with 027 versus non-027 ribotypes. We retrospectively collected clinical information about 123/136 patients with C. difficile infections admitted to hospitals in the East of England region in 2006 and from whom stool isolates were cultured and ribotyped as part of an earlier national survey. We defined severe C. difficile disease as having one or more of shock, paralytic ileus, pseudo membranous colitis or toxic megacolon. Patient median age was 83 years old (range 3 to 98, interquartile range 75 to 89), 86% were prescribed antibiotics in the eight weeks before illness onset, 41% had ribotype 027 and 30-day all cause mortality during hospital admission was 21%. Severe disease occurred in 24% (95%CI 13% to 37%) and 17% (95%CI 9% to 27%) of patients with PCR ribotype 027 and non-027 ribotypes respectively. In a multivariable model, ribotype 027 was not associated with severe disease after adjusting for sex, discharge from hospital prior to 60 days of current admission, gastroenteritis on admission, number of initiator antibiotics for C. difficile disease, and hospital where the patient was admitted.

CONCLUSIONS

Our study found no evidence to support previous assertions that ribotype 027 is more virulent than other PCR ribotypes. This finding raises questions about the contribution of this strain to the recent increase in C. difficile disease throughout North America and Europe.

Control of an outbreak of infection with the hypervirulent Clostridium difficile BI strain in a university hospital using a comprehensive "bundle" approach

BACKGROUND

In June 2000, the hospital-acquired Clostridium difficile (CD) infection rate in our hospital (University of Pittsburgh Medical Center-Presbyterian, Pittsburgh, PA) increased to 10.4 infections per 1000 hospital discharges (HDs); the annual rate increased from 2.7 infections per 1000 HDs to 7.2 infections per 1000 HDs and was accompanied by an increase in the frequency of severe outcomes. Forty-seven (51%) of 92 HA CD isolates in 2001 were identified as the "epidemic BI strain." A comprehensive CD infection control "bundle" was implemented to control the outbreak of CD infection.

METHODS

The CD infection control bundle consisted of education, increased and early case finding, expanded infection-control measures, development of a CD infection management team, and antimicrobial management. Process measures, antimicrobial usage, and hospital-acquired CD infection rates were analyzed, and CD isolates were typed.

RESULTS

The rates of compliance with hand hygiene and isolation were 75% and 68%, respectively. The CD management team evaluated a mean of 31 patients per month (11% were evaluated for moderate or severe disease). Use of antimicrobial therapy associated with increased CD infection risk decreased by 41% during the period 2003-2005 (P<.001). The aggregate rate of CD infection during the period 2001-2006 decreased to 4.8 infections per 1000 HDs (odds ratio, 2.2; 95% confidence interval, 1.4-3.1; P<.001) and by 2006, was 3.0 infections per 1000 HDs, a rate reduction of 71% (odds ratio, 3.5; 95% confidence interval, 2.3-5.4; P<.001). During the period 2000-2001, the proportion of severe CD cases peaked at 9.4% (37 of 393 CD infections were severe); the rate decreased to 3.1% in 2002 and further decreased to 1.0% in 2006--a 78% overall reduction (odds ratio, 20.3; 95% confidence interval, 2.8-148.2; P<.001). In 2005, 13% of CD isolates were type BI (20% were hospital acquired), which represented a significant reduction from 2001 (P<.001).

CONCLUSIONS

The outbreak of CD infection with the BI strain in our hospital was controlled after implementing a CD infection control "bundle." Early identification, coupled with appropriate control measures, reduces the rate of CD infection and the frequency of adverse events.

Implications of the changing face of Clostridium difficile disease for health care practitioners

Recent reported outbreaks of Clostridium difficile-associated disease in Canada have changed the profile of C difficile infections. Historically, C difficile disease was thought of mainly as a nosocomial disease associated with broad-spectrum antibiotics, and the disease was usually not life threatening. The emergence of an epidemic strain, BI/NAP1/027, which produces a binary toxin in addition to the 2 classic C difficile toxins A and B and is resistant to some fluoroquinolones, was associated with large numbers of cases with high rates of mortality. Recently, C difficile has been reported more frequently in nonhospital-based settings, such as community-acquired cases. The C difficile disease is also being reported in populations once considered of low risk (children and young healthy women). In addition, poor response to metronidazole treatment is increasing. Faced with an increasing incidence of C difficile infections and the changing profile of patients who become infected, this paper will reexamine the current concepts on the epidemiology and treatment of C difficile-associated disease, present new hypotheses for risk factors, examine the role of spores in the transmission of C difficile, and provide recommendations that may enhance infection control practices.

Antimicrobial therapy of Clostridium difficile-associated diarrhea

Clostridium difficile-associated diarrhea (CDAD) is the most common etiologically-defined cause of hospital-acquired diarrhea. Caused by the toxins of certain strains of C difficile, CDAD represents a growing concern, with epidemic outbreaks in some hospitals where very aggressive and difficult-to-treat strains have recently been found. Incidence of CDAD varies ordinarily between 1 to 10 in every 1,000 admissions. Evidence shows that CDAD increases morbidity, length of stay, and costs. This article described the clinical manifestations of CDAD, related risk factors, considerations for confirming CDAD, antimicrobial and non-antimicrobial treatment of CDAD, and issues related to relapses. The article concludes with a discussion of recent epidemic outbreaks involving CDAD.