Since publication of the Society for Healthcare Epidemiology of America position paper on Clostridium difficile infection in 1995, significant changes have occurred in the epidemiology and treatment ...of this infection. C. difficile remains the most important cause of healthcare-associated diarrhea and is increasingly important as a community pathogen. A more virulent strain of C. difficile has been identified and has been responsible for more-severe cases of disease worldwide. Data reporting the decreased effectiveness of metronidazole in the treatment of severe disease have been published. Despite the increasing quantity of data available, areas of controversy still exist. This guideline updates recommendations regarding epidemiology, diagnosis, treatment, and infection control and environmental management.
is the main causative agent of antibiotic-associated and health care-associated infective diarrhea. Recently, there has been growing interest in alternative sources of
other than patients with
...infection (CDI) and the hospital environment. Notably, the role of
-colonized patients as a possible source of transmission has received attention. In this review, we present a comprehensive overview of the current understanding of
colonization. Findings from gut microbiota studies yield more insights into determinants that are important for acquiring or resisting colonization and progression to CDI. In discussions on the prevalence of
colonization among populations and its associated risk factors, colonized patients at hospital admission merit more attention, as findings from the literature have pointed to their role in both health care-associated transmission of
and a higher risk of progression to CDI once admitted.
colonization among patients at admission may have clinical implications, although further research is needed to identify if interventions are beneficial for preventing transmission or overcoming progression to CDI.
Antimicrobial therapy plays a central role in the pathogenesis of Clostridium difficile infection (CDI), presumably through disruption of indigenous intestinal microflora, thereby allowing C. ...difficile to grow and produce toxin. Investigations involving animal models and studies performed in vitro suggest that inhibitory activity against C. difficile and differences in the propensity to stimulate toxin production may also influence the likelihood that particular drugs may cause CDI. Although nearly all antimicrobial classes have been associated with CDI, clindamycin, third-generation cephalosporins, and penicillins have traditionally been considered to harbor the greatest risk. Recent studies have also implicated fluoroquinolones as high-risk agents, a finding that is most likely to be related in part to increasing fluoroquinolone resistance among epidemic strains (i.e., restriction-endonuclease analysis group BI/North American PFGE type 1 strains) and some nonepidemic strains of C. difficile. Restrictions in the use of clindamycin and third-generation cephalosporins have been associated with reductions in CDI. Because use of any antimicrobial has the potential to induce the onset of CDI and disease caused by other health care–associated pathogens, antimicrobial stewardship programs that promote judicious use of antimicrobials are encouraged in concert with environmental and infection control–related efforts.
OBJECTIVE To determine the risk of Clostridium difficile transmission from index cases with C. difficile infection (CDI) to their household contacts and domestic pets. DESIGN A prospective study from ...April 2011 to June 2013. SETTING Patients with CDI from Canadian tertiary care centers. PARTICIPANTS Patients with CDI, their household human contacts, and pets. METHODS Epidemiologic information and stool or rectal swabs were collected from participants at enrollment and monthly for up to 4 months. Pulsed-field gel electrophoresis (PFGE) was performed on C. difficile isolates. Probable transmission was defined as the conversion of a C. difficile culture-negative contact to C. difficile culture-positive contact with a PFGE pattern indistinguishable or closely related to the index case. Possible transmission was defined as a contact with a positive C. difficile culture at baseline with a strain indistinguishable or closely related to the index case. RESULTS A total of 51 patients with CDI participated in this study; 67 human contacts and 15 pet contacts were included. Overall, 9 human contacts (13.4%) were C. difficile culture positive; 1 contact (1.5%) developed CDI; and 8 contacts were asymptomatic. Of 67 human contacts, probable transmission occurred in 1 human contact (1.5%) and possible transmission occurred in 5 human contacts (7.5%). Of 15 pet contacts, probable transmission occurred in 3 (20%) and possible transmission occurred in 1 (6.7%). CONCLUSIONS There was a high proportion of C. difficile culture positivity at 13.4% among human contacts and asymptomatic carriage of domestic pets reached 26.7%. These results suggest that household transmission of C. difficile may be a source of community-associated cases. Infect Control Hosp Epidemiol 2016;1-7.
In this prospective cohort study of patients admitted to hospitals in Quebec and Ontario, 2.8% of patients had
Clostridium difficile
infection and 3.0% had asymptomatic
C. difficile
colonization ...during hospitalization. Most patients with
C. difficile
infection had the NAP1 strain.
Clostridium difficile
is the leading cause of health care–associated infectious diarrhea.
1
After exposure to
C. difficile,
some patients remain asymptomatic, whereas others have illness ranging from mild diarrhea to fulminant colitis.
2
Outbreaks of
C. difficile
infection in North America and Europe have been attributed to the emergence of an epidemic strain (North American pulsed-field gel electrophoresis PFGE type 1 NAP1).
3
,
4
Risk factors for
C. difficile
infection include antibiotic use, advanced age, increased severity of underlying illness, prior hospitalization, use of feeding tubes, gastrointestinal surgery, and use of proton-pump inhibitors.
5
,
6
Variability in host factors may explain the wide spectrum . . .
Respiratory tract infections are frequent causes of hospitalization and initiation of empirical antimicrobial therapy. Testing for a broad panel of respiratory viruses has been advocated as a useful ...tool for antibiotic stewardship. We conducted a prospective observational study to assess the impact of rapid viral test results on antimicrobial prescriptions and clinical outcomes among hospitalized adults.
Eight hundred patients admitted with respiratory symptoms were tested by a 12-virus respiratory panel (RVP) during 3 consecutive winters in Montreal, Canada. The primary outcome measure was change in antimicrobial prescriptions (ie, de-escalation of empirical antimicrobial therapy or commencement of new antimicrobial therapy) after RVP results were available. Clinical outcomes were also assessed.
Influenza virus was identified in 53% of individuals in the study population, and other viruses were identified in 10%. Influenza virus positivity was associated with shorter duration of hospitalization and appropriate antiviral management. Antibiotic management was most significantly correlated with radiographic suspicion of pneumonia and less so with results of the RVP. Positivity for viruses other than influenza virus was not correlated with significantly different outcomes.
Physicians respond to results of testing for influenza virus when managing hospitalized adult patients but respond less to test results for other viruses. These data can inform the design of stewardship interventions and the selection of viral testing panels for hospitalized patients.
IMPORTANCE: Clostridium difficile infection (CDI) is a major cause of health care–associated infection worldwide, and new preventive strategies are urgently needed. Current control measures do not ...target asymptomatic carriers, despite evidence that they can contaminate the hospital environment and health care workers’ hands and potentially transmit C difficile to other patients. OBJECTIVE: To investigate the effect of detecting and isolating C difficile asymptomatic carriers at hospital admission on the incidence of health care–associated CDI (HA-CDI). DESIGN, SETTING, AND PARTICIPANTS: We performed a controlled quasi-experimental study between November 19, 2013, and March 7, 2015, in a Canadian acute care facility. Admission screening was conducted by detecting the tcdB gene by polymerase chain reaction on a rectal swab. Carriers were placed under contact isolation precautions during their hospitalization. MAIN OUTCOMES AND MEASURES: Changes in HA-CDI incidence level and trend during the intervention period (17 periods of 4 weeks each) were compared with the preintervention control period (120 periods of 4 weeks each) by segmented regression analysis and autoregressive integrated moving average (ARIMA) modeling. Concomitant changes in the aggregated HA-CDI incidence at other institutions in Québec City, Québec (n = 6) and the province of Québec (n = 94) were also examined. RESULTS: Overall, 7599 of 8218 (92.5%) eligible patients were screened, among whom 368 (4.8%) were identified as C difficile carriers. During the intervention, 38 patients (3.0 per 10 000 patient-days) developed an HA-CDI compared with 416 patients (6.9 per 10 000 patient-days) during the preintervention control period (P < .001). There was no immediate change in the level of HA-CDIs on implementation (P = .92), but there was a significant decrease in trend over time of 7% per 4-week period (rate ratio, 0.93; 95% CI, 0.87-0.99 per period; P = .02). ARIMA modeling also detected a significant effect of the intervention, represented by a gradual progressive decrease in the HA-CDI time series by an overall magnitude of 7.2 HA-CDIs per 10 000 patient-days. We estimated that the intervention had prevented 63 of the 101 (62.4%) expected cases. By contrast, no significant decrease in HA-CDI rates occurred in the control groups. CONCLUSIONS AND RELEVANCE: Detecting and isolating C difficile carriers was associated with a significant decrease in the incidence of HA-CDI. If confirmed in subsequent studies, this strategy could help prevent HA-CDI.
Using whole genome sequencing of isolates from a cohort of patients with Clostridium difficile infection (CDI) and colonization, we found that incident CDI cases were more likely to be linked to an ...infected than colonized donor.
Abstract
Background
Whole genome sequencing (WGS) studies can enhance our understanding of the role of patients with asymptomatic Clostridium difficile colonization in transmission.
Methods
Isolates obtained from patients with Clostridium difficile infection (CDI) and colonization identified in a study conducted during 2006-2007 at 6 Canadian hospitals underwent typing by pulsed-field gel electrophoresis, multilocus sequence typing, and WGS. Isolates from incident CDI cases not in the initial study were also sequenced where possible. Ward movement and typing data were combined to identify plausible donors for each CDI case, as defined by shared time and space within predefined limits. Proportions of plausible donors for CDI cases that were colonized, infected, or both were examined.
Results
Five hundred fifty-four isolates were sequenced successfully, 353 from colonized patients and 201 from CDI cases. The NAP1/027/ST1 strain was the most common strain, found in 124 (62%) of infected and 92 (26%) of colonized patients. A donor with a plausible ward link was found for 81 CDI cases (40%) using WGS with a threshold of ≤2 single nucleotide polymorphisms to determine relatedness. Sixty-five (32%) CDI cases could be linked to both infected and colonized donors. Exclusive linkages to infected and colonized donors were found for 28 (14%) and 12 (6%) CDI cases, respectively.
Conclusions
Colonized patients contribute to transmission, but CDI cases are more likely linked to other infected patients than colonized patients in this cohort with high rates of the NAP1/027/ST1 strain, highlighting the importance of local prevalence of virulent strains in determining transmission dynamics.
This study investigated the relationship between hospital exposures, intestinal microbiota, and subsequent risk of Clostridium difficile-associated disease (CDAD), with use of a nested case-control ...design. The study included 599 patients, hospitalized from September 2006 through May 2007 in Montreal, Quebec, from whom fecal samples were obtained within 72 h after admission; 25 developed CDAD, and 50 matched controls were selected for analysis. Nonsteroidal anti-inflammatory drugs and antibiotic use were associated with CDAD. Fecal specimens were evaluated by 16S ribosomal RNA microarray to characterize bacteria in the intestinal microbiota during the at-risk period. Probe intensities were higher for Firmicutes, Proteobacteria, and Actinobacteria in the patients with CDAD, compared with controls, whereas probe intensities for Bacteroidetes were lower. After epidemiologic factors were controlled for, only Bacteroidetes and Firmicutes remained significantly and independently associated with development of CDAD. Hospital exposures were associated with changes in the intestinal microbiota and risk of CDAD, and these changes were not driven exclusively by antimicrobial use.
To evaluate common hand hygiene methods for efficacy in removing Clostridium difficile.
Randomized crossover comparison among 10 volunteers with hands experimentally contaminated by nontoxigenic C. ...difficile.
Interventions included warm water with plain soap, cold water with plain soap, warm water with antibacterial soap, antiseptic hand wipes, alcohol-based handrub, and a control involving no intervention. All interventions were evaluated for mean reduction in colony-forming units (CFUs) under 2 contamination protocols: "whole hand" and "palmar surface." Results were analyzed according to a Bayesian approach, by using hierarchical models adjusted for multiple observations.
Under the whole-hand protocol, the greatest adjusted mean reductions were achieved by warm water with plain soap (2.14 log(10) CFU/mL 95% credible interval (CrI), 1.74-2.54 log(10) CFU/mL), cold water with plain soap (1.88 log(10) CFU/mL 95% CrI, 1.48-2.28 log(10) CFU/mL), and warm water with antibacterial soap (1.51 log(10) CFU/mL 95% CrI, 1.12-1.91 log(10) CFU/mL), followed by antiseptic hand wipes (0.57 log(10) CFU/mL 95% CrI, 0.17-0.96 log(10) CFU/mL). Alcohol-based handrub (0.06 log(10) CFU/mL 95% CrI, -0.34 to 0.45 log(10) CFU/mL) was equivalent to no intervention. Under the palmar surface protocol, warm water with plain soap, cold water with plain soap, and warm water with antibacterial soap again yielded the greatest mean reductions, followed by antiseptic hand wipes (26.6, 26.6, 26.6, and 21.9 CFUs per plate, respectively), when compared with alcohol-based handrub. Hypothenar (odds ratio, 10.98 95% CrI, 1.96-37.65) and thenar (odds ratio, 6.99 95% CrI, 1.25-23.41) surfaces were more likely than fingertips to remain heavily contaminated after handwashing.
Handwashing with soap and water showed the greatest efficacy in removing C. difficile and should be performed preferentially over the use of alcohol-based handrubs when contact with C. difficile is suspected or likely.
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