Detection of clostridium difficile antigen and toxin in stool specimens: Comparison of the C. difficile quik chek complete enzyme immunoassay and GeneXpert C. difficile polymerase chain reaction assay

Clostridium difficile in inflammatory bowel disease

PURPOSE OF REVIEW

The chronic inflammatory bowel diseases (IBD), Crohn's disease, and ulcerative colitis, are associated with an increased risk of symptomatic Clostridium difficile infection (CDI). CDI may also masquerade as an IBD flare and complicate IBD management. This review provides a comprehensive overview of the epidemiology, diagnosis, and treatment of CDI in IBD patients.

RECENT FINDINGS

CDI remains common in IBD with complications including flares in disease activity, recurrent CDI episodes, and prolonged hospital stays. Newer IBD therapeutics including vedolizumab, ustekinumab, and tofacitinib are less likely to cause severe CDI. A high index of suspicion, rapid testing via a two-step method, and prompt treatment with vancomycin or fidaxomicin are paramount to managing CDI in IBD patients. Strategies to prevent recurrent CDI (rCDI) include the monoclonal antibody bezlotoxumab as well as fecal microbiota transplantation (FMT). FMT has a robust profile of safety and effectiveness in preventing rCDI in adults and children.

SUMMARY

Clinicians must remain vigilant in the prompt diagnosis and treatment of CDI in IBD patients. Corticosteroids, unnecessary antibiotics, and ongoing colonic inflammatory disease are modifiable risk factors. Improved infection control measures, newer IBD medications, and using effective CDI treatments will facilitate a reduced burden of severe CDI and complications for IBD patients.

An insight into Clostridioides difficile-associated diarrhea in Saudi children: diagnosis and treatment

INTRODUCTION

Clostridioides difficile infection (CDI) is a major cause for antibiotic-associated diarrhea. Specific factors put the pediatrics at risk. International guidelines lists specific recommendations for the diagnosis and treatment of pediatric CDI. The practice of diagnosing and treating pediatric CDI in Saudi Arabia is slightly different from the recommendations of the guidelines.

AREAS COVERED

This review summarizes pediatric CDI in Saudi Arabia in terms of epidemiology, current diagnostics, and how the practice compares to recommendations of the guidelines, and available treatment options.

EXPERT OPINION

Although pediatric CDI epidemiology in Saudi Arabia doesn't impose a burden on the healthcare system, it should be noted that not all hospitals follow CDI diagnostic recommendations of international guidelines, which may result in cases underreporting. However, due to the presumed low CDI prevalence, the traditional regimen of oral metronidazole for non-severe CDI remains effective, whereas vancomycin is used for severe cases. While fidaxomicin is approved for pediatrics, its high acquisition cost and low CDI rates make it challenging for hospitals to use it. Overall, pediatrics at risk of CDI recurrence should be evaluated, such as reviewing current antibiotics for potential discontinuation. Future studies evaluating the epidemiology and treatment for CDI in Saudi children are needed.

Is the Medium Still the Message? Culture-Independent Diagnosis of Gastrointestinal Infections

Infectious diarrhea is caused by a variety of pathogens, including viruses, bacteria, and parasitic organisms. Though the causative agent of diarrhea has historically been evaluated via stool cultures, recently, culture-independent diagnostic tests (CIDT) have been developed and utilized with increasing frequency. Current practice guidelines recommend their use as adjuncts to stool cultures for diagnosing acute and chronic diarrhea. The three principal CIDT are microscopy, enzyme-based immunoassays (EIAs), and molecular based polymerase chain reaction (PCR). This review explores the common causes of infectious diarrhea, the basics of stool culture, the diagnostic utility of these three culture-independent modalities, and the strengths and weaknesses of all currently available clinical techniques. It also outlines considerations for specific populations including returning travelers and those with inflammatory bowel disease.

Frequency of toxin genes and antibiotic resistance pattern of Clostridioides difficile isolates in diarrheal samples among hospitalized patients in Hamadan, Iran

AIM

This study was designed to investigate the prevalence of Clostridioides difficile, its toxin-producing genes, and antibiotic resistance patterns in diarrheal samples from hospitalized patients in Hamadan, Iran.

BACKGROUND

Today, concerns over Clostridioides difficile infection (CDI) have significantly increased due to reduced susceptibility to antibiotics used for CDI treatment. Toxins produced by C. difficile strains are associated with disease severity and outcome.

METHODS

In this cross-sectional study, a total of 130 diarrheal samples of patients admitted to different wards of three hospitals in Hamadan from November 2018 to September 2019 were collected. C. difficile isolates were identified by culture on CCFA and PCR (Polymerase chain reaction). The presence of toxin-encoding genes (tcdA and tcdB) and binary toxin genes (cdtA and cdtB) was analyzed by PCR. Resistance of the isolates to metronidazole, vancomycin and clindamycin antibiotics was determined using agar dilution method.

RESULTS

Out of 130 diarrheal samples from hospitalized patients, 16 (12.3%) C. difficile isolates were obtained. PCR results were positive for two toxin-producing genes, tcdA and tcdB, in all (100%) C. difficile isolates, and the binary toxin genes cdtA and cdtB were detected in 6 (37.5%) and 8 (50%) isolates, respectively. The results of antibiotic susceptibility testing showed resistance to metronidazole, vancomycin, and clindamycin in 3 (18.7%), 3 (18.7%), and 2 (12.5%) isolates, respectively, and all isolates were resistant to rifampicin.

CONCLUSION

The results of this study showed toxigenic C. difficile with tcdA ⁺ /tcdB ⁺ profile is a major cause of nosocomial diarrhea in Hamadan, and clinical laboratories should routinely perform C. difficile diagnostic testing on diarrheal specimens of hospitalized patients. Resistance to conventional antibiotic therapy against C. difficile should be considered as a warning to prevent irrational administration of antibiotics.

Clostridioides difficile infections in Saudi Arabia: Where are we standing?

Clostridioides difficile infections (CDIs) are infamous healthcare-associated infections for causing watery diarrhea to long-term hospitalized patients with a high mortality rate. Epidemiological reports from western countries showed up-trending pattern in the number of CDIs cases. It is becoming immensely challenging for routine diagnostic protocols to detect CDIs accurately with short turnaround time. In Saudi Arabia, there is a paucity of data about CDIs’ prevalence, recurrence rate, methods of screening and mortality rate. Nevertheless, a growing number of cases with similar virulence strains and comparable antibiotic resistance pattern to the western countries counterparts reported data were also detected. This review aims to present the status of CDIs’ diagnosis and incidence rate in Saudi Arabia based on current literature.

Diarrhoea in critical care is rarely infective in origin, associated with increased length of stay and higher mortality

Diarrhoea, defined as > 3 loose or liquid stools per day, affects 9.7-41% of intensive care unit patients, negatively impacting on patient dignity, intensifying nursing workload and increasing morbidity. Its pathogenesis is poorly understood, but infective agents, intensive care unit therapies (such as enteral feed) and critical illness changes in the gut microbiome are thought to play a role. We analysed a consecutive cohort of 3737 patients admitted to a mixed general intensive care unit. Diarrhoea prevalence was lower than previously reported (5.3%), rarely infective in origin (6.5%) and associated with increased length of stay (median (inter-quartile range) 2.3 (1.0-5.0) days vs. 10 days (5.0-22.0), p < 0.001, sub-distribution hazard ratio 0.55 (95% CI 0.48-0.63), p < 0.001) and mortality (9.5% vs. 18.1%, p = 0.005, sub-distribution hazard ratio 1.20 (95% CI 0.79-1.81), p = 0.40), compared to patients without diarrhoea. In addition, 17.1% of patients received laxatives <24 h prior to diarrhoea onset. Further research on diarrhoea's pathogenesis in critical care is required; robust treatment protocols, investigation rationalisation and improved laxative prescribing may reduce its incidence and improve related outcomes.

Performance Evaluation of the Luminex Aries C. difficile Assay in Comparison to Two Other Molecular Assays within a Multihospital Health Care Center

Clostridioides difficile infection (CDI) remain a serious issue in the United States. Fast and accurate diagnosis of CDI is paramount to achieve immediate infection control initiation, triaging, and isolation, as well as appropriate antibiotic treatment. However, both, over- and underdiagnosis can lead to adverse patient outcomes, such as unnecessary administration of antibiotics or unwanted spread of spores in any hospital setting, respectively.

Clostridioides difficile infection (CDI) remain a serious issue in the United States. Fast and accurate diagnosis of CDI is paramount to achieve immediate infection control initiation, triaging, and isolation, as well as appropriate antibiotic treatment. However, both, over- and underdiagnosis can lead to adverse patient outcomes, such as unnecessary administration of antibiotics or unwanted spread of spores in any hospital setting, respectively. In this prospective study, we evaluated the FDA-cleared Aries C. difficile assay and compared its performance and workflow characteristics to those of the BD Max Cdiff and Xpert C. difficile/Epi assays. Out of 302 samples tested, 55 (18.2%) samples were positive, and 234 (77.5%) samples were negative for C. difficile by all three testing methods. Comparison results showed a positive and negative percent agreement (PPA and NPA, respectively) between the Aries and Xpert assays of 95.2% (59/62) and 99.2% (238/240), respectively. The PPA and NPA between the Aries and BD Max assays were 91.8% (56/61) and 96.6% (230/238), respectively. Invalid result rates were determined to be 2.6% for the BD Max assay, 1.0% for the Aries assay, and 0% for the Xpert assay. Hands-on time (HoT) and total turnaround time (TAT) varied considerably depending on the sample number and instrument throughput. The HoT ranged from 1.2 to 3.5 min per sample, and the TAT was 1 to 2.3 h. Overall, the results demonstrated that the Aries assay is a rapid and sensitive method for the diagnosis of CDI in clinical laboratories.

Burden of Clostridium (Clostridioides) difficile Infection among Patients in Western Asia: A Systematic Review and Meta-Analysis

BACKGROUND

Clostridium difficile is the most common causes of hospital-acquired diarrhea affecting particularly hospitalized patients globally. This organism has re-emerged in recent years with significant morbidity and mortality. The present study aimed to estimate the burden of C. difficile infection (CDI) and to acquire information on the overall rates of community- and hospital-acquired CDI in western Asia.

METHODS

A systematic literature search was performed to identify articles published from the eight Persian Gulf countries in western Asia including Iran, Iraq, Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates in the electronic databases within Jan of 2000 to Dec of 2017. Then, 20 publications which met our inclusion criteria were selected for data extraction and analysis by Comprehensive Meta-Analysis Software.

RESULTS

Twenty studies reported the prevalence of toxigenic strains of C. difficile among patients from Persian Gulf countries, of these the pooled prevalence of CDI was 9% (95% CI: 6.5%-12.5%). Totally, 8 studies showed the prevalence of hospital-acquired CDI, from those studies the prevalence of CDI was estimated 8.4% (95% CI: 4.9%-14.1%). Moreover, 7 studies reported the prevalence of community-acquired CDI, from those studies the prevalence of CDI was estimated 1.8% (95% CI: 1.2%-2.9%).

CONCLUSION

The prevalence of CDI in western Asia is lower than southern and eastern region. Moreover, the lower prevalence of community-acquired CDI compared to hospital-acquired CDI, indicate that the source of infection in western Asia is more likely in the hospitals.

Clostridium difficile-associated Diarrhea in Developing Countries: A Systematic Review and Meta-Analysis

INTRODUCTION

The prevalence of Clostridium difficile infection is rapidly increasing worldwide, but prevalence is difficult to estimate in developing countries where awareness, diagnostic resources, and surveillance protocols are limited. As diarrhea is the hallmark symptom, we conducted a systematic review and meta-analysis to determine the prevalence and incidence of C. difficile infection in patients in these regions who presented with diarrhea.

METHODS

We conducted a systematic literature search of MEDLINE/PubMed, Scopus, and Latin-American and Caribbean Health Sciences Literature databases to identify and analyze data from recent studies providing prevalence or incidence rates of C. difficile-associated diarrhea in developing countries within four regions: Africa-Middle East, developing Asia, Latin America, and China. Our objectives were to determine the current prevalence and incidence density rates of first episodes of C. difficile-associated diarrhea in developing countries.

RESULTS

Within the regions included in our analysis, prevalence of C. difficile infection in patients with diarrhea was 15% (95% CI 13-17%) (including community and hospitalized patients), with no significant difference across regions. The incidence of C. difficile infection in 17 studies including this information was 8.5 per 10,000 patient-days (95% CI 5.83-12.46). Prevalence was significantly higher in hospitalized patients versus community patients (p  = 0.0227).

CONCLUSION

Our prevalence estimate of 15% is concerning; however, low awareness and inconsistent diagnostic and surveillance protocols suggest this is markedly underestimated. Enhanced awareness and management of C. difficile infection in patients with diarrhea, along with improvements in infection control and surveillance practices, should be implemented to reduce prevalence of C. difficile-associated diarrhea in developing countries.

FUNDING

Pfizer Inc.

Searching for a Potential Algorithm for Clostridium difficile Testing at a Tertiary Care Hospital: Does Toxin Enzyme Immunoassay Testing Help?

Clostridium difficile is a major contributor to morbidity and mortality in the United States. Methods for identifying the organism in stool include molecular platforms, enzyme immunoassays (EIAs) for toxin, and culture. Controversy persists over whether molecular tests are too sensitive at identifying C. difficile, and there are questions about how additional laboratory information could inform clinical management and reduce over treatment. The aim of this study was to assess whether clinical factors are related to the toxin status of patients and whether information about toxin status could potentially inform clinical management of patients. A total of 201 PCR-positive C. difficile stool samples from adult patients at our institution underwent EIA toxin testing. Clinical and laboratory data were collected, and the percentage of PCR-positive/EIA-positive (PCR⁺/EIA⁺) patients and PCR⁺ and EIA-negative (PCR⁺/EIA^-) patients was calculated. Of the 201 samples, 47% were EIA positive and 53% were EIA negative. Although PCR⁺/EIA⁺ patients were more likely to have had a prior C. difficile infection (P = 0.015), there was no statistical difference between the additional data collected that correlated with a positive EIA result. We were unable to show that patients with an EIA⁺ result had worse clinical parameters than those with EIA^- results and concluded that establishing a testing algorithm that included both PCR and EIA testing would not change the clinical management of patients at our hospital.