Causes, Burden, and Prevention of Clostridium difficile Infection

Infrequent intrahousehold transmission of Clostridioides difficile between pet owners and their pets

Companion animals have been shown to carry Clostridioides difficile strains that are similar or identical to strains found in people, and a small number of studies have shown that pets carry genetically identical C. difficile isolates as their owners, suggesting inter-species transmission. However, the directionality of transmission is ultimately unknown, and the frequency with which animals acquire C. difficile following their owners' infection is unclear. The goal of this study was to assess how often pets belonging to people with C. difficile infection carry genetically related C. difficile isolates. We enrolled pet owners from two medical institutions (University of Pennsylvania Health System (UPHS) and The Ohio State University Wexner Medical Center (OSUWMC)) who had diarrhoea with or without positive C. difficile assays and tested their faeces and their pets' faeces for C. difficile using both anaerobic culture and PCR assays. When microorganisms were obtained from both the owner and pet and had the same toxin profile or ribotype, isolates underwent genomic sequencing. Faecal samples were obtained from a total of 59 humans, 72 dogs and 9 cats, representing 47 complete households (i.e. where a sample was available from the owner and at least one pet). Of these, C. difficile was detected in 30 humans, 10 dogs and 0 cats. There were only two households where C. difficile was detected in both the owner and pet. In one of these households, the C. difficile isolates were of different toxin profiles/ribotypes (A+/B+ / RT 499 from the owner, A-/B- / RT PR22386 from the dog). In the other household, the isolates were genetically identical (one SNP difference). Interestingly, the dog from this household had recently received a course of antibiotics (cefpodoxime and metronidazole). Our findings suggest that inter-species transmission of C. difficile occurs infrequently in households with human C. difficile infections.

Health care consequences of hospitalization with Clostrioides difficile infection: a propensity score matching study

Background

Clostridiodies difficile infection (CDI) has been characterized by the Center for Disease Control and Prevention (CDC) as an urgent public health threat and a major concern in hospital, outpatient and extended-care facilities worldwide.

Methods

A retrospective cohort study of patients aged ≥ 18 hospitalized with CDI in New York State (NYS) between January 1, 2014–December 31, 2016. Data were extracted from NY Statewide Planning and Research Cooperative (SPARCS) and propensity score matching was performed to achieve comparability of the CDI (exposure) and non-CDI (non-exposure) groups. Of the 3,714,486 hospitalizations, 28,874 incidence CDI cases were successfully matched to 28,874 non-exposures.

Results

The matched pairs comparison demonstrated that CDI cases were more likely to be readmitted to the hospital at 30 (28.26% vs. 19.46%), 60 (37.65% vs. 26.02%), 90 (42.93% vs. 30.43) and 120 days (46.47% vs. 33.74), had greater mortality rates at 7 (3.68% vs. 2.0%) and 180 days (20.54% vs. 11.96%), with significant increases in length of stay and total hospital charges (p < .001, respectively).

Conclusions

CDI is associated with a large burden on patients and health care systems, significantly increasing hospital utilization, costs and mortality.

Intestinal Parasitic Infections Among Pediatric Patients in a Metropolitan City of Bangladesh With Emphasis on Cryptosporidiosis

Introduction Gastrointestinal parasitic infections are one of the global health concerns in developing countries like Bangladesh. Among them, Cryptosporidium spp. plays an essential role in causing diarrhea, malnutrition, and poor cognitive function, especially in children. This study was conducted to identify the frequency of Cryptosporidium cases and other parasitic agents.  Methods A cross-sectional observational study was conducted among 219 hospitalized children with diarrhea. The conventional microscopic technique was applied for parasitic detection. Particular staining (modified Ziehl-Neelsen) procedure was performed to identify oocysts of Cryptosporidium spp. A polymerase chain reaction (PCR) was performed to determine the SSU rRNA and gp60 gene of Cryptosporidium.  Results Cysts of Giardia duodenalis (2.3%), ova of Ascaris lumbricoides (1.4%,), Trichuris trichiura (0.5%), and both A. lumbricoides and T. trichiura (0.9%) were identified in samples through wet mount preparation. The distribution of Cryptosporidium spp. as detected by the staining method and nested PCR was 1.4% and 4.1%, respectively.  Conclusion Factors independently associated with Cryptosporidium infection are unsafe water, lack of regular hand washing, and insufficiency of exclusive breastfeeding. This study reports, presumably for the first time, the detection of Cryptosporidium oocysts in Chattogram metropolitan city of Bangladesh.

Genetic and phenotypic characteristics of Clostridium (Clostridioides) difficile from canine, bovine, and pediatric populations

Objectives:

Carriage of Clostridioides difficile by different species of animals has led to speculation that animals could represent a reservoir of this pathogen for human infections. The objective of this study was to compare C. difficile isolates from humans, dogs, and cattle from a restricted geographic area.

Methods:

C. difficile isolates from 36 dogs and 15 dairy calves underwent whole genome sequencing, and phenotypic assays assessing growth and virulence were performed. Genomes of animal-derived isolates were compared to 29 genomes of isolates from a pediatric population as well as 44 reference genomes.

Results:

Growth rates and relative cytotoxicity of isolates were significantly higher and lower, respectively, in bovine-derived isolates compared to pediatric- and canine-derived isolates. Analysis of core genes showed clustering by host species, though in a few cases, human strains co-clustered with canine or bovine strains, suggesting possible interspecies transmission. Geographic differences (e.g., farm, litter) were small compared to differences between species. In an analysis of accessory genes, the total number of genes in each genome varied between host species, with 6.7% of functional orthologs differentially present/absent between host species and bovine-derived strains having the lowest number of genes. Canine-derived isolates were most likely to be non-toxigenic and more likely to carry phages. A targeted study of episomes identified in local pediatric strains showed sharing of a methicillin-resistance plasmid with dogs, and historic sharing of a wide range of episomes across hosts. Bovine-derived isolates harbored the widest variety of antibiotic-resistance genes, followed by canine

Conclusions:

While C. difficile isolates mostly clustered by host species, occasional co-clustering of canine and pediatric-derived isolates suggests the possibility of interspecies transmission. The presence of a pool of resistance genes in animal-derived isolates with the potential to appear in humans given sufficient pressure from antibiotic use warrants concern.

Clostridioides difficile on dairy farms and potential risk to dairy farm workers

Clostridioides difficile causes severe colitis in people and is a significant enteric pathogen in many species of animals, including swine, horses, and potentially cattle. C. difficile is shed in feces, and transmission occurs horizontally via the fecal-oral route. Livestock has been suggested as a potential reservoir for C. difficile, and while studies have shown that swine and farm workers can be colonized with identical clones of C. difficile, the zoonotic transmission of C. difficile from livestock to people has not been definitively demonstrated. The goal of this study was to determine whether dairy calves and dairy farm workers harbored genetically similar isolates of C. difficile. First, we validated a glove juice protocol for detecting C. difficile on farm workers' hands. We then visited 23 farms and collected 1) fecal samples from 92 dairy calves, 2) hand rinsates from 38 dairy farm workers, and 3) fecal samples from five of the dairy farm workers who were willing to submit them. All samples underwent anaerobic culture and qPCR to detect C. difficile. C. difficile was detected on 15 of the farms (65.2%, 95% confidence interval (CI) 42.7%-83.6%) and in 28 calves (30.4%, 95% CI 21.2-40.9%) but in none of the hand rinsates or human fecal samples. Thus, the zoonotic transmission of C. difficile on dairy farms could not be demonstrated, and dairy farmers did not appear to be at increased risk of acquiring C. difficile via the fecal-oral route.

Pet Ownership Protects Against Recurrence of Clostridioides difficile Infection

Background

Clostridioides difficile infection (CDI) is the leading cause of antibiotic-associated and health care–associated diarrhea in humans. Recurrent CDI (R-CDI) occurs in ~20%–30% of patients with CDI and results in increased morbidity, mortality, and hospital costs. Genomic analyses have shown overlap of C. difficile isolates from animals and people, suggesting that a zoonotic reservoir may contribute to recurrence. The objective of this study was to determine whether pet ownership is a risk factor for recurrence of CDI.

Methods

We conducted a case–control study among patients with recurrent CDI (cases; n = 86) and patients with nonrecurrent CDI (controls; n = 146). Multivariable logistic regression modeling was used to determine the association between recurrence of CDI and pet ownership while accounting for patient-level risk factors.

Results

Pet ownership was not significantly associated with recurrence of CDI (odds ratio [OR], 1.02; 95% confidence interval [CI], 0.38–2.72; P = 0.965) among all patients (n = 232). However, among the subset of patients with community-associated or community-onset health care facility–acquired CDI (n = 127), increasing contact with pets was increasingly protective against recurrence: for every point increase in a pet contact score (out of 7 possible points), the odds of recurrence decreased by 14% (OR, 0.86; 95% CI, 0.74–1.00; P = 0.051).

Conclusions

Close interactions with pets appear protective against the recurrence of community-acquired CDI. A potential mechanism may involve beneficial contributions to the microbiota of pet owners afflicted with CDI, as has been observed for other conditions such as atopy, obesity, and food allergies. However, more research is needed to understand the interactions between pets, owners, and their microbiota.

Promoting appropriate urine culture management to improve health care outcomes and the accuracy of catheter-associated urinary tract infections

Published literature indicates that the unjustified ordering or improper collection of urine for urinalysis or culture from either catheterized patients or those without indwelling devices, or misinterpretation of positive results, often leads to adverse health care events, including increased financial burdens, overreporting of mandated catheter-associated urinary tract infection events, overtreatment of patients with antimicrobial agents, selection of multidrug-resistant organisms, and Clostridium difficile infection. Moreover, national guidelines that provide evidence-based direction on core processes that form the basis for subsequent clinical therapy decisions or surveillance interpretations; that is, the appropriate ordering and collection of urine for laboratory testing and the treatment of patients with symptomatic urinary tract infection, are not widely known or lack adherence. This article provides published evidence on the influence of inappropriate ordering of urine specimens and subsequent treatment of asymptomatic bacteriuria and associated adverse effects; reviews research on bacterial contamination and preservation; and delineates best practices in the collection, handling, and testing of urine specimens for culture or for biochemical analysis in both catheterized and noncatheterized patients. The goal is to provide infection preventionists (IPs) with a cohesive evidence-based framework that will assist them in facilitating the implementation of a urine culture management program that reduces patient harms, enhances the accuracy of catheter-associated urinary tract infection surveillance, improves antibiotic stewardship, and reduces costs.

Infection prevention and control of Clostridium difficile: a global review of guidelines, strategies, and recommendations

BACKGROUND

Clostridium difficile is the leading cause of health care-associated infections. Given the high incidence of C. difficile infection (CDI) and the lack of primary prevention through immunization, health care professionals should be aware of the most current guidance, as well as strengths and limitations of the evidence base underpinning this guidance.

METHODS

We identified publicly available national or organizational guidelines related to CDI infection and prevention control (IPC) published between 2000 and 2015 and for any health care setting through an internet search using the Google search engine. We reviewed CDI-targeted IPC recommendations and describe the assessment of evidence in available guidelines.

RESULTS

We identified documents from 28 countries/territories, mainly from acute care hospitals in North America, the Western Pacific, and Europe (18 countries). We identified only a few specific recommendations for long-term care facilities (LTCFs) and from countries in South America (Uruguay and Chile), South East Asia (Thailand), and none for Africa or Eastern Mediterranean. Of 10 IPC areas, antimicrobial stewardship was universally recognized as essential and supported by high quality evidence. Five other widely reported "strong" recommendations were: effective environment cleaning (including medical equipment), case isolation, use of personal protective equipment, surveillance, and education. Several unresolved and emerging issues were documented and currently available evidence was classified mainly as of mixed quality.

CONCLUSION

Our review underlines the need for targeted CDI IPC guidelines in several countries and for LTCFs. International harmonisation on the assessment of the evidence for best practices is needed as well as more robust evidence to support targeted recommendations.

Diagnosis and Treatment of Clostridium difficile Infection (CDI)

Early and accurate diagnosis is essential for optimal treatment of individuals with Clostridium difficile infection (CDI) and for implementation of effective infection control procedures. The decision about which diagnostic test to use is an important one that should be based on test sensitivity, specificity, and predictive value. The challenges of CDI go beyond rapid identification and management of symptomatic patients. Asymptomatic carriage has long been suspected in C. difficile transmission, but it may play a larger role than previously thought. Emerging information also shows that patients treated for CDI remain colonized for many weeks after symptom resolution. In fact, stool culture positivity increases during the first weeks following treatment completion. Treatments that reduce the duration and degree of asymptomatic shedding could have added benefit for reduced transmission.