Clinical Practice Guidelines for Clostridium difficile Infection in Adults and Children: 2017 Update by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA)

Enzymatic Transition States and Drug Design

Transition state theory teaches that chemically stable mimics of enzymatic transition states will bind tightly to their cognate enzymes. Kinetic isotope effects combined with computational quantum chemistry provides enzymatic transition state information with sufficient fidelity to design transition state analogues. Examples are selected from various stages of drug development to demonstrate the application of transition state theory, inhibitor design, physicochemical characterization of transition state analogues, and their progress in drug development.

Clostridium difficile colonization among patients with clinically significant diarrhea and no identifiable cause of diarrhea

OBJECTIVE

To determine the prevalence of Clostridium difficile colonization among patients who meet the 2017 IDSA/SHEA C. difficile infection (CDI) Clinical Guideline Update criteria for the preferred patient population for C. difficile testing.

DESIGN

Retrospective cohort.

SETTING

Tertiary-care hospital in St. Louis, Missouri.PatientsPatients whose diarrheal stool samples were submitted to the hospital's clinical microbiology laboratory for C. difficile testing (toxin EIA) from August 2014 to September 2016.InterventionsElectronic and manual chart review were used to determine whether patients tested for C. difficile toxin had clinically significant diarrhea and/or any alternate cause for diarrhea. Toxigenic C. difficile culture was performed on all stool specimens from patients with clinically significant diarrhea and no known alternate cause for their diarrhea.

RESULTS

A total of 8,931 patients with stool specimens submitted were evaluated: 570 stool specimens were EIA positive (+) and 8,361 stool specimens were EIA negative (-). Among the EIA+stool specimens, 107 (19% of total) were deemed eligible for culture. Among the EIA- stool specimens, 515 (6%) were eligible for culture. One EIA+stool specimen (1%) was toxigenic culture negative. Among the EIA- stool specimens that underwent culture, toxigenic C. difficile was isolated from 63 (12%).

CONCLUSIONS

Most patients tested for C. difficile do not have clinically significant diarrhea and/or potential alternate causes for diarrhea. The prevalence of toxigenic C. difficile colonization among EIA- patients who met the IDSA/SHEA CDI guideline criteria for preferred patient population for C. difficile testing was 12%.

The use of faecal microbiota transplant as treatment for recurrent or refractory Clostridium difficile infection and other potential indications: joint British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS) guidelines

Interest in the therapeutic potential of faecal microbiota transplant (FMT) has been increasing globally in recent years, particularly as a result of randomised studies in which it has been used as an intervention. The main focus of these studies has been the treatment of recurrent or refractory Clostridium difficile infection (CDI), but there is also an emerging evidence base regarding potential applications in non-CDI settings. The key clinical stakeholders for the provision and governance of FMT services in the UK have tended to be in two major specialty areas: gastroenterology and microbiology/infectious diseases. While the National Institute for Health and Care Excellence (NICE) guidance (2014) for use of FMT for recurrent or refractory CDI has become accepted in the UK, clear evidence-based UK guidelines for FMT have been lacking. This resulted in discussions between the British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS), and a joint BSG/HIS FMT working group was established. This guideline document is the culmination of that joint dialogue.

The C. difficile puzzle: Putting it all together

This article explores Clostridium difficile infection (CDI) versus colonization, regulations surrounding CDI reporting, the varied types of CDI testing methods available, and the important role nurses have in thoughtful submission of stool specimens for C. difficile testing.

Clostridium difficile infection perceptions and practices: a multicenter qualitative study in South Africa

Background

Clostridium difficile infection (CDI) is understudied in limited resource settings. In addition, provider awareness of CDI as a prevalent threat is unknown. An assessment of current facilitators and barriers to CDI identification, management, and prevention is needed in limited resource settings to design and evaluate quality improvement strategies to effectively minimize the risk of CDI.

Methods

Our study aimed to identify CDI perceptions and practices among healthcare providers in South African secondary hospitals to identify facilitators and barriers to providing quality CDI care. Qualitative interviews (11 physicians, 11 nurses, 4 pharmacists,) and two focus groups (7 nurses, 3 pharmacists) were conducted at three district level hospitals in the Cape Town Metropole. Semi-structured interviews elicited provider perceived facilitators, barriers, and opportunities to improve clinical workflow from patient presentation through CDI (1) Identification, (2) Diagnosis, (3) Treatment, and (4) Prevention. In addition, a summary provider CDI knowledge score was calculated for each interviewee for seven components of CDI and management.

Results

Major barriers identified were knowledge gaps in characteristics of C. difficile identification, diagnosis, treatment, and prevention. The median overall CDI knowledge score (scale 0–7) from individual interviews was 3 [interquartile range 0.25, 4.75]. Delays in C. difficile testing workflow were identified. Participants perceived supplies for CDI management and prevention were usually available; however, hand hygiene and use of contact precautions was inconsistent.

Conclusions

Our analysis provides a detailed description of the facilitators and barriers to CDI workflow and can be utilized to design quality improvement interventions among limited resource settings.

Current pharmacotherapeutic options for pediatric lower respiratory tract infections with a focus on antimicrobial agents

Introduction: Antibiotics are frequently prescribed to children in the community and in nosocomial settings, mainly because of lower respiratory tract infections(LRTIs), which include influenza, bronchitis, bronchiolitis, pneumonia, and tuberculosis, in addition to bronchiectasis and cystic fibrosis lung disease. It is important to note, however, that more than 50% of these prescriptions are unnecessary or inappropriate. Areas covered: The current choice of antimicrobial therapy for etiological agents of LRTIs is examined and discussed considering each type of LRTI. Expert opinion: There is a clear need for the appropriate utilization of antibiotics in children. Therefore, accurate drug selection and choice of best dosage and duration of the antibacterial treatment are important to optimize the treatment of LRTIs. It's fundamental to bear in mind that children differ from adults in how LRTIs manifest and evolve not only because of the diversity in the immunological profiles but also the fundamental age-related differences in absorption, distribution, metabolism, and elimination of drugs. Since comprehensive antibiotic guideline recommendations for the treatment of pediatric LRTIs are generally lacking, there is an undeniable need for the introduction of pediatric antimicrobial stewardship programmes in both community and hospital settings.

Ultrasensitive Detection of Clostridioides difficile Toxins A and B by Use of Automated Single-Molecule Counting Technology

Current tests for the detection of Clostridioides (formerly Clostridium) difficile free toxins in feces lack sensitivity, while nucleic acid amplification tests lack clinical specificity. We have evaluated the Singulex Clarity C. diff toxins A/B assay (currently in development), an automated and rapid ultrasensitive immunoassay powered by single-molecule counting technology, for detection of C. difficile toxin A (TcdA) and toxin B (TcdB) in stool. The analytical sensitivity, analytical specificity, repeatability, and stability of the assay were determined. In a clinical evaluation, frozen stool samples from 311 patients with suspected C. difficile infection were tested with the Clarity C. diff toxins A/B assay, using an established cutoff value. Samples were tested with the Xpert C. difficile/Epi assay, and PCR-positive samples were tested with an enzyme immunoassay (EIA) (C. Diff Quik Chek Complete). EIA-negative samples were further tested with a cell cytotoxicity neutralization assay. The limits of detection for TcdA and TcdB were 0.8 and 0.3 pg/ml in buffer and 2.0 and 0.7 pg/ml in stool, respectively. The assay demonstrated reactivity to common C. difficile strains, did not show cross-reactivity to common gastrointestinal pathogens, was robust against common interferents, allowed detection in fresh and frozen stool samples and in samples after three freeze-thaw cycles, and provided results with high reproducibility. Compared to multistep PCR and toxin-testing procedures, the Singulex Clarity C. diff toxins A/B assay yielded 97.7% sensitivity and 100% specificity. The Singulex Clarity C. diff toxins A/B assay is ultrasensitive and highly specific and may offer a standalone solution for rapid detection and quantitation of free toxins in stool.

Clostridium difficile infection in oncology patients: epidemiology, pathophysiology, risk factors, diagnosis, and treatment

Clostridium difficile infection (CDI) is one of the most common healthcare-associated infections in the United States. Its incidence has been increasing in the recent years despite preventative measures. CDI increases annual expenses by 1.5 billion dollars. Cancer patients are at higher risk to acquire CDI, as explained by their frequent exposure to risk factors. CDI in cancer patients is associated with higher mortality rates and prolonged hospitalization. Furthermore, CDI affects the course of the disease by delaying treatments such as chemotherapy. Chemotherapeutics drugs are considered independent risk factors for CDI. This review discusses Clostridium difficile infection in cancer patients, including those who are receiving chemotherapy. Herein, we summarize recent data regarding the epidemiology, risk factors, including chemotherapy regimens, pathogenesis, diagnostic techniques and treatment options, including newer agents. Method: A literature search was performed using the PubMed and Google Scholar databases. The MeSH terms utilized in different combinations were 'clostridium difficile', 'neoplasia/cancer/oncology', 'chemotherapy', 'diagnosis', and 'treatment', in addition to looking up each treatment option individually to generate a comprehensive search. The articles were initially screened by title alone, followed by screening through abstracts. Full texts of pertinent articles (including letters to editors, case reports, case series, cohort studies, and clinical trials) were included in this review.

Vulnerability of long-term care facility residents to Clostridium difficile infection due to microbiome disruptions

Aging presents a significant risk factor for Clostridium difficile infection (CDI). A disproportionate number of CDIs affect individuals in long-term care facilities compared with the general population, likely due to the vulnerable nature of the residents and shared environment. Review of the literature cites a number of underlying medical conditions such as the use of antibiotics, proton pump inhibitors, chemotherapy, renal disease and feeding tubes as risk factors. These conditions alter the intestinal environment through direct bacterial killing, changes to pH that influence bacterial stabilities or growth, or influence nutrient availability that direct population profiles. In this review, we examine some of the contributing risk factors for elderly associated CDI and the toll they take on the microbiome.

Clostridioides difficile Infection

Clostridioides difficile (formerly Clostridium difficile) infection is the most frequently identified health care-associated infection in the United States. C difficile has also emerged as a cause of community-associated diarrhea, resulting in increased incidence of community-associated infection. Clinical illness ranges in severity from mild diarrhea to fulminant colitis and death. Appropriate management of infection requires understanding of the various diagnostic assays and therapeutic options as well as relevant measures to infection prevention. This article provides updated recommendations regarding the prevention, diagnosis, and treatment of incident and recurrent C difficile infection.

A microbiological study to investigate the carriage and transmission-potential of Clostridium difficile spores on single-use and reusable sharps containers

BACKGROUND

A 2015 study matching use of disposable and reusable sharps containers (DSCs, RSCs) with Clostridium difficile infection (CDI) incidence found a decreased incidence with DSCs. We conducted microbiologic samplings and examined the literature and disease-transmission principles to evaluate the scientific feasibility of such an association.

METHODS

(i) 197 RSCs were sampled for C. difficile at processing facilities; (ii) RSCs were challenged with high C. difficile densities to evaluate efficacy of automated decontamination; and (iii) 50 RSCs and 50 DSCs were sampled in CDI patient rooms in 7 hospitals. Results were coupled with epidemiologic studies, clinical requirements, and chain-of-infection principles, and tests of evidence of disease transmission were applied.

RESULTS

C. difficile spores were found on 9 of 197 (4.6%) RSCs prior to processing. Processing completely removed C. difficile. In CDI patient rooms, 4 of 50 RSCs (8.0%) and 8 of 50 DSCs (16.0%) had sub-infective counts of C. difficile (P = .27). DSCs were in permanent wall cabinets; RSCs were removed and decontaminated frequently.

CONCLUSION

With C. difficile bioburden being sub-infective on both DSCs and RSCs, sharps containers being no-touch, and glove removal required after sharps disposal, we found 2 links in the chain of infection to be broken and 5 of 7 tests of evidence to be unmet. We conclude that sharps containers pose no risk of C. difficile transmission.

Diagnostic stewardship and the 2017 update of the IDSA-SHEA Clinical Practice Guidelines for Clostridium difficile Infection

Diagnostic stewardship is an increasingly recognized means to reduce unnecessary tests and diagnostic errors. As a leading cause of healthcare-associated infection for which accurate laboratory diagnosis remains a challenge, Clostridium difficile offers an ideal opportunity to apply the principles of diagnostic stewardship. The recently updated 2017 Infectious Diseases Society of America (IDSA)-Society for Healthcare Epidemiology of America (SHEA) Clinical Practice Guidelines for C. difficile infection now recommend separate diagnostic strategies depending on whether an institution has adopted diagnostic stewardship in test decision making. IDSA-SHEA endorsement of diagnostic stewardship for C. difficile highlights the increasing role of diagnostic stewardship in hospitals. In this opinion piece, we introduce the concept of diagnostic stewardship by discussing the new IDSA-SHEA diagnostic recommendations for laboratory diagnosis of C. difficile . We outline recent examples of diagnostic stewardship, challenges to implementation, potential downsides and propose future areas of study.

Infections in Older Adults: A Case-Based Discussion Series Emphasizing Antibiotic Stewardship

INTRODUCTION

Compared with younger populations, adults 65 years and older are more likely to suffer infection-related morbidity and mortality, experience antibiotic-related adverse events, and acquire multidrug-resistant organisms. We developed a series of case-based discussions that stressed antibiotic stewardship while addressing management of common infections in older adults.

METHODS

Five 1-hour case-based discussions address recognition, diagnosis, and management of infections common in older adults, including those living in long-term care settings: urinary tract infections, upper respiratory tract infections, lower respiratory tract infections, skin and soft tissue infections, and Clostridium difficile infection. The education was implemented at the skilled nursing centers at 15 Veterans Affairs medical centers. Participants from an array of disciplines completed an educational evaluation for each session as well as a pre- and postcourse knowledge assessment.

RESULTS

The number of respondents to the educational evaluation administered following each session ranged from 68 to 108. Learners agreed that each session met its learning objectives (4.80-4.89 on a 5-point Likert scale, 5 = strongly agree) and that they were likely to make changes (2.50-2.89 on a 3-point scale, 3 = highly likely to make changes). The average score on the five-question knowledge assessment increased from 3.6 (72%) to 3.9 (78%, p = .06).

DISCUSSION

By stressing recognition of atypical signs and symptoms of infection in older adults, diagnostic tests, and antibiotic stewardship, this series of five case-based discussions enhanced clinical training of learners from several disciplines.

Regulating stool for microbiota transplantation

In 2017 Gut Microbes published "A proposed definition of microbiota transplantation for regulatory purposes," in which the authors suggest that regulators should draw a line between microbiota transplants and biologic drugs composed of microbial communities (or other products derived from the human microbiome). They develop a definition of microbiota transplantation (MT) to help regulators draw such a line, and suggest that MT need not be, and cannot be, regulated as a biologic drug (a live biotherapeutic product). However, an agency's regulatory scrutiny of a medical product should be commensurate with that product's degree of risk to patients. Products for MT, such as stool, are likely to be as or more dangerous than more highly manipulated microbial products that scientists and regulators agree should be regulated as biologic drugs. Therefore, we argue that MT, as defined by the authors, should receive the same regulatory oversight as any other biologic product intended to cure, mitigate, treat, or prevent disease. We also suggest that regulators might not be able to operationalize the proposed definition of MT.

Extended duration vancomycin in recurrent Clostridium difficile infection: a systematic review

Clostridium difficile infections have a high recurrence rate following acute treatment. Extended duration vancomycin (EDV) is a mainstay for the treatment of recurrent Clostridium difficile infections (rCDI). Clinical disease guidelines recommend a variety of different vancomycin treatment regimens though based on weak, low-quality evidence. Patients typically receive an initial vancomycin treatment course of 7-14 days for the acute infection, followed by an extended duration vancomycin course. Multiple publications on the utility of EDV regimens have been published but few include reported effectiveness outcomes associated with a prescribed treatment regimen. The purpose of this review is to evaluate the safety and efficacy data on extended duration vancomycin regimens used in recurrent clostridium treatment. Five articles, three case series and two randomized open-label clinical trials, were identified which included both elements. Outcomes were evaluable in 174 patients, 31 from randomized trials, with prior average recurrent episodes ranging from 3 to 4. Vancomycin dose ranged from 3500 to >6800 mg with therapy durations extending from 21 days to over 60 days. Follow-up duration ranged from 10 weeks to 12 months. Case series reported success rates for EDV in rCDI from 61% to 100%, while randomized trials found lower success rates from 26% to 58%. Taper and pulse regimens reported superior outcomes compared to pulse-only regimens, 58-100% versus 26-81%, respectively. Comparative EDV data is limited. Current available data supports an EDV regimen which includes both a daily dosing taper followed by an every 48 or 72 h pulse.

Fecal Host Transcriptomics for Non-Invasive Human Mucosal Immune Profiling: Proof of Concept in Clostridium Difficile Infection

Background:

Host factors play an important role in pathogenesis and disease outcome in Clostridium difficile infection (CDI), and characterization of these responses could uncover potential host biomarkers to complement existing microbe-based diagnostics.

Methods:

We extracted RNA from fecal samples of patients with CDI and profiled human mRNA using amplicon-based next-generation sequencing (NGS). We compared the fecal host mRNA transcript expression profiles of patients with CDI to controls with non-CDI diarrhea.

Results:

We found that the ratio of human actin gamma 1 (ACTG1) to 16S ribosomal RNA (rRNA) was highly correlated with NGS quality as measured by percentage of reads on target. Patients with CDI could be differentiated from those with non-CDI diarrhea based on their fecal mRNA expression profiles using principal component analysis. Among the most differentially expressed genes were ones related to immune response (IL23A, IL34) and actin-cytoskeleton function (TNNT1, MYL4, SMTN, MYBPC3, all adjusted P-values < 1 x 10^-3).

Conclusions:

In this proof-of-concept study, we used host fecal transcriptomics for non-invasive profiling of the mucosal immune response in CDI. We identified differentially expressed genes with biological plausibility based on animal and cell culture models. This demonstrates the potential of fecal transcriptomics to uncover host-based biomarkers for enteric infections.

Preventable Patient Harm: a Multidisciplinary, Bundled Approach to Reducing Clostridium difficile Infections While Using a Glutamate Dehydrogenase/Toxin Immunochromatographic Assay/Nucleic Acid Amplification Test Diagnostic Algorithm

Health care facility-onset Clostridium difficile infections (HO-CDI) are an important national problem, causing increased morbidity and mortality. HO-CDI is an important metric for the Center for Medicare and Medicaid Service's (CMS) performance measures. Hospitals that fall into the worst-performing quartile in preventing hospital-acquired infections, including HO-CDI, may lose millions of dollars in reimbursement. Under pressure to reduce CDI and without a clear optimal method for C. difficile detection, health care facilities are questioning how best to use highly sensitive nucleic acid amplification tests (NAATs) to aid in the diagnosis of CDI. Our institution has used a two-step glutamate dehydrogenase (GDH)/toxin immunochromatographic assay/NAAT algorithm since 2009. In 2016, our institution set an organizational goal to reduce our CDI rates by 10% by July 2017. We achieved a statistically significant reduction of 42.7% in our HO-CDI rate by forming a multidisciplinary group to implement and monitor eight key categories of infection prevention interventions over a period of 13 months. Notably, we achieved this reduction without modifying our laboratory algorithm. Significant reductions in CDI rates can be achieved without altering sensitive laboratory testing methods.

Clostridium difficile Infection in Children

Clostridium difficile is an important cause of health care associated infections. The epidemiology of C. difficile infection (CDI) in children has changed over the past few decades. There is now a higher incidence in hospitalized children, and there has been an emergence of community-onset infection. A hypervirulent strain, North American pulse type 1, has also developed. Neonates and young infants have high rates of colonization but rarely have symptoms. The well-known risk factor for CDI in children age 2 years or older is antibiotic use. Inflammatory bowel disease and cancer are associated with increased incidence and severity of CDI. Nucleic acid amplification tests are now widely used for diagnosis given their rapid turnover and higher sensitivity and specificity. The treatment for an initial episode and first recurrence is oral metronidazole. Oral vancomycin is reserved for second recurrence or severe cases. A new treatment option, fecal bowel transplant, has been reported to be safe and effective in adults, and studies are now being conducted in children. [Pediatr Ann. 2018;47(9):e359-e365.].

A Guide to Utilization of the Microbiology Laboratory for Diagnosis of Infectious Diseases: 2018 Update by the Infectious Diseases Society of America and the American Society for Microbiology

The critical nature of the microbiology laboratory in infectious disease diagnosis calls for a close, positive working relationship between the physician/advanced practice provider and the microbiologists who provide enormous value to the healthcare team. This document, developed by experts in laboratory and adult and pediatric clinical medicine, provides information on which tests are valuable and in which contexts, and on tests that add little or no value for diagnostic decisions. This document presents a system-based approach rather than specimen-based approach, and includes bloodstream and cardiovascular system infections, central nervous system infections, ocular infections, soft tissue infections of the head and neck, upper and lower respiratory infections, infections of the gastrointestinal tract, intra-abdominal infections, bone and joint infections, urinary tract infections, genital infections, and other skin and soft tissue infections; or into etiologic agent groups, including arthropod-borne infections, viral syndromes, and blood and tissue parasite infections. Each section contains introductory concepts, a summary of key points, and detailed tables that list suspected agents; the most reliable tests to order; the samples (and volumes) to collect in order of preference; specimen transport devices, procedures, times, and temperatures; and detailed notes on specific issues regarding the test methods, such as when tests are likely to require a specialized laboratory or have prolonged turnaround times. In addition, the pediatric needs of specimen management are also emphasized. There is intentional redundancy among the tables and sections, as many agents and assay choices overlap. The document is intended to serve as a guidance for physicians in choosing tests that will aid them to quickly and accurately diagnose infectious diseases in their patients.

Cost-effectiveness analysis of ribotype-guided fecal microbiota transplantation in Chinese patients with severe Clostridium difficile infection

Background

Clostridium difficile infection (CDI) caused by ribotype 002 strain is associated with poor outcomes in Chinese patients. Fecal microbiota transplantation (FMT) is an effective but costly treatment for CDI. We aimed to examine potential cost-effectiveness of ribotype-guided FMT in Chinese patients with severe CDI.

Methods

A decision-analytic model was designed to simulate outcomes of ribotype 002-guided FMT versus vancomycin treatment in Chinese patients with severe CDI in the hospital setting. Outcome measures included mortality rate; direct medical cost; and quality-adjusted life year (QALY) loss for CDI. Sensitivity analysis was performed to examine robustness of base-case results.

Results

Comparing to vancomycin treatment, ribotype-guided FMT group reduced mortality (11.6% versus 17.1%), cost (USD8,807 versus USD9,790), and saved 0.472 QALYs in base-case analysis. One-way sensitivity analysis found the ribotype-guided FMT group to remain cost-effective when patient acceptance rate of FMT was >0.6% and ribotype 002 prevalence was >0.07%. In probabilistic sensitivity analysis, ribotype-guided FMT gained higher QALYs at 100% of simulations with mean QALY gain of 0.405 QALYs (95%CI: 0.400–0.410; p<0.001). The ribotype-guided group was less costly in 97.9% of time, and mean cost-saving was USA679 (95%CI: 670–688; p<0.001).

Conclusions

In the present model, ribotype-guided FMT appears to be a potential option to save QALYs and cost when comparing with vancomycin. The cost-effectiveness of ribotype-guided FMT is subject to the patient acceptance to FMT and prevalence of ribotype 002.

Sensitivity of Single-Molecule Array Assays for Detection of Clostridium difficile Toxins in Comparison to Conventional Laboratory Testing Algorithms

Guidelines recommend the use of an algorithm for the laboratory diagnosis of Clostridium difficile infection (CDI). Enzyme immunoassays (EIAs) detecting C. difficile toxins cannot be used as standalone tests due to suboptimal sensitivity, and molecular tests suffer from nonspecificity by detecting colonization.

Guidelines recommend the use of an algorithm for the laboratory diagnosis of Clostridium difficile infection (CDI). Enzyme immunoassays (EIAs) detecting C. difficile toxins cannot be used as standalone tests due to suboptimal sensitivity, and molecular tests suffer from nonspecificity by detecting colonization. Sensitive immunoassays have recently been developed to improve and simplify CDI diagnosis. Assays detecting CD toxins have been developed using single-molecule array (SIMOA) technology. SIMOA performance was assessed relative to a laboratory case definition of CDI defined by positive glutamate dehydrogenase (GDH) screen and cell cytotoxicity neutralizing assay (CCNA). Samples were tested with SIMOA assays and a commercial toxin EIA to compare performance, with discrepancy resolution using a commercial nucleic acid-based test and a second cell cytotoxicity assay. The SIMOA toxin A and toxin B assays showed limits of detection of 0.6 and 2.9 pg/ml, respectively, and intra-assay coefficients of variation of less than 10%. The optimal clinical thresholds for the toxin A and toxin B assays were determined to be 22.1 and 18.8 pg/ml, respectively, with resultant sensitivities of 84.8 and 95.5%. In contrast, a high-performing EIA toxin test had a sensitivity of 71.2%. Thus, the SIMOA assays detected toxins in 24% more samples with laboratory-defined CDI than the high performing toxin EIA (95% [63/66] versus 71% [47/66]). This study shows that SIMOA C. difficile toxin assays have a higher sensitivity than currently available toxin EIA and have the potential to improve CDI diagnosis.

Impact of Delayed Oral Vancomycin for Severe Clostridium difficile Infection

Background: Treatment of severe Clostridium difficile infection (CDI) with oral vancomycin (VAN) is known to be superior to treatment with metronidazole (MDZ). However, previous studies have not evaluated the impact on patients when oral VAN therapy is delayed after diagnosis of severe CDI. Materials and Methods: This was a single-center, retrospective study of adult patients who were diagnosed with severe CDI. The objective was to compare clinical outcomes for patients treated initially with oral VAN versus patients receiving delayed oral VAN after at least 48 hours of initial treatment with MDZ. The primary outcome was all-cause in-hospital mortality. Results: There were 101 patients who comprised the initial oral VAN group, while 20 patients comprised the delayed oral VAN group. There was no significant difference in all-cause in-hospital mortality for patients in the initial oral VAN treatment group compared to those who had delayed oral VAN therapy (4.95% vs 15.00%, P = 0.13). Patients who were initially treated with oral VAN experienced a significantly higher rate of clinical cure (49.50% vs 20.00%, P = 0.02), shorter median postinfection length of hospitalization (7.0 days vs 13.0 days, P < 0.001), shorter median time to resolution of leukocytosis (3.9 days vs 10.4 days, P = 0.01), and were less likely to have an end of treatment serum creatinine greater than 1.5 times their baseline (8.7% vs 29.4%, P = 0.03). Conclusion: Patients who receive oral VAN as their initial treatment for severe CDI experience improved clinical outcomes compared to patients receiving delayed oral VAN after being initially treated with MDZ.

Epidemiology and outcomes of Clostridium difficile infection among hospitalised patients: results of a multicentre retrospective study in South Africa

Introduction

Limited data exist on Clostridium difficile infection (CDI) in low-resource settings and settings with high prevalence of HIV. We aimed to determine baseline CDI patient characteristics and management and their contribution to mortality.

Methods

We reviewed adult patients hospitalised with diarrhoea and a C. difficile test result in 2015 from four public district hospitals in the Western Cape, South Africa. The primary outcome measures were risk factors for mortality. Secondary outcomes were C. difficile risk factors (positive vs negative) and CDI treatment.

Results

Charts of patients with diarrhoea tested for C. difficile (n=250; 112 C. difficile positive, 138 C. difficile negative) were reviewed. The study population included more women (65%). C. difficile-positive patients were older (46.5 vs 40.7 years, p<0.01). All-cause mortality was more common in the C. difficile-positive group (29% vs 8%, p<0.0001; HR 2.0, 95% CI 1.1 to 3.6). Tuberculosis (C. difficile positive 54% vs C. difficile negative 32%, p<0.001), 30-day prior antibiotic exposure (C. difficile positive 83% vs C. difficile negative 46%, p<0.001) and prior hospitalisation (C. difficile positive 55% vs C. difficile negative 22%, p<0.001) were also more common in the C. difficile-positive group. C. difficile positive test result (OR 4.7, 95% CI 2.0 to 11.2; p<0.001), male gender (OR 2.8, 95% CI 1.1 to 7.2; p=0.031) and tuberculosis (OR 2.3, 95% CI 1.0 to 5.0; p=0.038) were independently associated with mortality. Of patients starting treatment, metronidazole was the most common antimicrobial therapy initiated (70%, n=78); 32 C. difficile-positive (29%) patients were not treated.

Conclusion

Patients testing positive for C. difficile are at high risk of mortality at public district hospitals in South Africa. Tuberculosis should be considered an additional risk factor for CDI in populations with high tuberculosis and HIV comorbidity. Interventions for CDI prevention and management are urgently needed.

Prise en charge des patients ayant une maladie inflammatoire chronique de l’intestin hospitalisés en médecine intensive et réanimation

Les patients ayant une maladie inflammatoire chronique de l’intestin (MICI) [maladie de Crohn ou rectocolite hémorragique] ont une probabilité plus importante d’être hospitalisés en médecine intensive et réanimation (MIR) soit en raison de leur traitement immunosuppresseur et/ou biothérapie (parfois associés) qui est à l’origine d’un surrisque d’infections notamment respiratoires soit en raison d’un risque accru de thromboses veineuses profondes ou artérielles. Ces complications directement ou non liées à la MICI sont associées à une morbidité et à une mortalité accrues. Certaines de ces complications peuvent être prévenues notamment par une vaccination adaptée des patients traités par immunosuppresseurs et par la prescription systématique d’une héparine de bas poids moléculaire chez tout patient ayant une MICI en poussée et/ou hospitalisé quelle qu’en soit la raison.

Management of Primary and Recurrent Clostridium difficile Infection: An Update

Background: Clostridium difficile infection (CDI) is one of the most common healthcare-associated infections (HAI) in the United States and Canada, and incidence rates have increased worldwide in recent decades. Currently, antibiotics are the mainstay treatments for both primary and recurrent CDI, but their efficacy is limited, prompting further therapies to be developed. Aim: This review summarizes current and emerging therapies in CDI management including antibiotics, fecal microbiota transplantation, monoclonal antibodies, spore-based therapies, and vaccinations.

Primary Prevention of Clostridium difficile-Associated Diarrhea: Current Controversies and Future Tools

PURPOSE OF REVIEW

Clostridium difficile infection (CDI) is a major cause of morbidity and mortality in hospitalized patients and rates in most places have not decreased significantly despite broad efforts by both hospitals and public health entities. This review aims to provide readers with a better understanding of the limitations of current prevention strategies. We also review potential future tools that may be available for the primary prevention of CDI in the next decade.

RECENT FINDINGS

Research over the last decade has expanded our appreciation of the role of asymptomatic shedding in the healthcare setting and in the community. This review demonstrates that poor quality data underlies even well-established guidance from national authorities on basic topics such as contact precautions, avoidance of alcohol-based hand hygiene products, CDI testing, supplemental cleaning modalities, and the use of bleach solutions. Additionally, we review research on novel preventative interventions such as identification of asymptomatic carriers, supplemental environmental cleaning technologies, vaccines, and the manipulation of the intestinal microbiome. While there is preliminary data that supports further research in all of these areas, the research is not yet robust enough on which to base local or national policy recommendations, though late-phase human clinical trials of CDI vaccine trials are ongoing. Over the last decade, researchers have begun to reassess the traditional infection prevention model for CDI. Data suggesting a greater role for asymptomatic shedders has increased our understanding of current vertical prevention techniques and is forcing researchers to look more at new processes and technologies to decrease disease incidence.

Retrospective evaluation of fidaxomicin versus oral vancomycin for treatment of Clostridium difficile infections in allogeneic stem cell transplant

OBJECTIVE/BACKGROUND

Clostridium difficile infection (CDI) is a potential complication during hematopoietic stem cell transplantation (HSCT), and no specific recommendations exist regarding treatment of CDI in allogeneic SCT patients. Use of metronidazole and oral vancomycin has been associated with clinical failure. Fidaxomicin has previously been found noninferior to the use of oral vancomycin for the treatment of CDI, and no studies have compared the use of oral vancomycin with fidaxomicin for the treatment of CDI in allogeneic SCT.

METHODS

This retrospective chart review included 96 allogeneic SCT recipients who developed CDI within 100 days following transplantation. Participants were treated with oral vancomycin (n = 52) or fidaxomicin (n = 44). The primary outcome was clinical cure, defined as no need for further retreatment 2 days following completion of initial CDI treatment. Secondary outcomes were global cure, treatment failure, and recurrent disease.

RESULTS

No differences in clinical cure were observed between patients receiving oral vancomycin or fidaxomicin (75% vs. 75%, p = 1.00). Secondary outcomes were similar between oral vancomycin and fidaxomicin in regards to global cure (66% vs. 67%, p = .508), treatment failure (28% vs. 27%, p = .571), and recurrent disease (7% vs. 5%, p = .747). In a subanalysis of individuals that developed acute graft-versus-host disease following CDI, the difference in mean onset of acute graft-versus-host disease was 21.03 days in the oral vancomycin group versus 32.88 days in the fidaxomicin group (p = .0031).

CONCLUSION

The findings of this study suggest that oral vancomycin and fidaxomicin are comparable options for CDI treatment in allogeneic SCT patients within 100 days following transplant.

In vitro stability of three oral vancomycin preparations stored at 2- 5 °C and ambient room temperature for up to 60 days against 100 Clostridioides (Clostridium) difficile and 51Staphylococcus aureus strains

Oral vancomycin is used to treat Clostridioides (Clostridium) difficile infection. Several different preparations are available including reconstituted IV solutions, vancomycin capsules, and grape flavored vancomycin oral solution kit (CutisPharma). The shelf life for IV after reconstitution varies between 7 and 14 days under refrigeration, and a standard 30 days for vancomycin oral solution kit (CutisPharma). The impact of storage on the in vitro potency was determined in 3 different vancomycin preparations by measuring MICs for 100 strains of C. difficile and 25 strains of Staphylococcus aureus, at T₀, 14, 30, and 60 days, stored at ambient (RT) and refrigerated (2-5 °C) temperatures. All vancomycin preparations showed potency over a period of 60 days regardless of storage conditions. However, the capsule preparation showed mold after 60 days at room temperature, but unlike vancomycin oral solution kit, which retained a clear appearance, the IV and capsule preps showed evidence of crystallization.

Fidaxomicin vs Vancomycin for the Treatment of a First Episode of Clostridium Difficile Infection: A Meta-analysis and Systematic Review

Clostridium difficile infection (CDI) continues to possess a significant disease burden in the United States (US) as well as all over the world. Given the increase in severity and recurrence rate, the decrease in cure rate, and the fact that the virulent ribotype 027 strain remains one of the most commonly identified strains in the US, the Infectious Diseases Society of America (IDSA) published a clinical practice guideline in February 2018 moving away from metronidazole as the first-line treatment for initial CDI and recommending either oral vancomycin or fidaxomicin. The aim of this study is to evaluate the clinical data available comparing the efficacy of primary treatment of CDI between those two antibiotics. We performed a PubMed, PubMed Central, and ScienceDirect database search without restriction to regions, publication types, or languages. A comprehensive literature search was performed from January 1, 1980 up to March 20, 2018. We used the following keywords in different combinations: Clostridium difficile, Clostridium difficile infection, CDI, C. diff, C. difficile, fidaxomicin, vancomycin, pseudomembranous colitis, and antibiotic-associated colitis. The search was limited to human studies. Data were independently extracted by two reviewers with disagreements resolved by a third author. We pooled an odds ratio (OR) on two primary outcomes: Clinical cure rate and rate of recurrence during the follow-up period. The computer search was also supplemented with manual searches by the authors of the retrieved review articles and primary studies. The search phrase “((Clostridium difficile) AND vancomycin) AND fidaxomicin” had the highest yield results. We identified four observational studies with a total of 2,303 patients with CDI that met our inclusion criteria. Compared with vancomycin, fidaxomicin use was associated with a significantly lower recurrence of CDI with a pooled OR of 0.47 (95% confidence interval (CI), 0.37 - 0.60, I2 = 0). On the other hand, there was no significant association of fidaxomicin use with CDI cure rate compared to vancomycin with a pooled OR of 1.22 (95% CI, 0.93 - 1.60, I2 = 0). In light of the recently updated clinical practice guidelines by the IDSA, our review suggests that fidaxomicin has a more sustained clinical response with a statistically significant lower recurrence rate. Although fidaxomicin appears to be the better drug with statistical significance, its cost-effectiveness continues to be an ongoing controversy. More randomized clinical trials are needed to shed light on this matter to assess if there is any clinical significance in fidaxomicin superiority.

Rapid Fire: Infectious Disease Emergencies in Patients with Cancer

Patients with cancer can be immunocompromised because of their underlying malignancy as well as the medical therapies with which they are treated. Infections frequently present atypically and can be challenging to diagnose. The spectrum of infectious diseases encountered in patients receiving chemotherapy, hematopoietic stem cell transplant, and immunotherapy is broad depending on the depth of immunosuppression. Early recognition of infectious processes followed by appropriate diagnostic testing, imaging, and empiric antibiotic therapy in the emergency department are critical to providing optimal care and improving survival in this complex patient population.

A Small Molecule-Screening Pipeline to Evaluate the Therapeutic Potential of 2-Aminoimidazole Molecules Against Clostridium difficile

Antibiotics are considered to be the first line of treatment for mild to moderately severe Clostridium difficile infection (CDI) in humans. However, antibiotics are also risk factors for CDI as they decrease colonization resistance against C. difficile by altering the gut microbiota and metabolome. Finding compounds that selectively inhibit different stages of the C. difficile life cycle, while sparing the indigenous gut microbiota is important for the development of alternatives to standard antibiotic treatment. 2-aminoimidazole (2-AI) molecules are known to disrupt bacterial protection mechanisms in antibiotic resistant bacteria such as Pseudomonas aeruginosa, Acinetobacter baumannii, and Staphylococcus aureus, but are yet to be evaluated against C. difficile. A comprehensive small molecule-screening pipeline was developed to investigate how novel small molecules affect different stages of the C. difficile life cycle (growth, toxin, and sporulation) in vitro, and a library of commensal bacteria that are associated with colonization resistance against C. difficile. The initial screening tested the efficacy of eleven 2-AI molecules (compound 1 through 11) against C. difficile R20291 compared to a vancomycin (2 μg/ml) control. Molecules were selected for their ability to inhibit C. difficile growth, toxin activity, and sporulation. Further testing included growth inhibition of other C. difficile strains (CD196, M68, CF5, 630, BI9, M120) belonging to distinct PCR ribotypes, and a commensal panel (Bacteroides fragilis, B. thetaiotaomicron, C. scindens, C. hylemonae, Lactobacillus acidophilus, L. gasseri, Escherichia coli, B. longum subsp. infantis). Three molecules compound 1 and 2, and 3 were microbicidal, whereas compounds 4, 7, 9, and 11 inhibited toxin activity without affecting the growth of C. difficile strains and the commensal microbiota. The antimicrobial and anti-toxin effects of 2-AI molecules need to be further characterized for mode of action and validated in a mouse model of CDI.

Presence of multiple Clostridium difficile strains at primary infection is associated with development of recurrent disease

Recurrence of Clostridium difficile infection (CDI) places a major burden on the healthcare system. Previous studies have suggested that specific C. difficile strains, or ribotypes, are associated with severe disease and/or recurrence. However, in some patients a new strain is detected in subsequent infections, complicating longitudinal studies focused on strain differences that may contribute to disease outcome. We examined ribotype composition over time in patients who did or did not develop recurrence to examine infection with multiple C. difficile ribotypes (mixed infection), during the course of infection. Using a retrospective patient cohort, we isolated and ribotyped a median of 36 C. difficile colonies from 61 patients (105 total samples) at initial infection, recurrence (a second case of CDI within 15-56 days of initial infection), and reinfection (a second case of CDI after 56 days of initial infection). We observed mixed infection in 78.6% of samples at initial infection in patients who went on to develop recurrence compared to 18.1% of patients who did not, and mixed infection remained associated with subsequent recurrence after adjusting for gender and prior antibiotic exposure (OR 3.5, 95% CI 1.3-9.4, P = .015). In patients who were sampled longitudinally (44 consecutive events in 32 patients), the dominant ribotype changed in 31.8% of consecutive samples and the newly dominant ribotype was not detected in prior samples from that patient. Our results suggest that mixed C. difficile infection is more prevalent than previously demonstrated and potentially a marker of susceptibility to recurrence.

A Rapid, Accurate, Single Molecule Counting Method Detects Clostridium difficile Toxin B in Stool Samples

We describe a new rapid and accurate immunoassay-based technology capable of counting single target molecules using digital imaging without magnification. Using the technology, we developed a rapid test for Clostridium difficile toxin B, which is responsible for the pathology underlying potentially fatal C. difficile infections (CDI). There are currently no tests for CDI that are rapid, sensitive, and specific. The MultiPath C. difficile toxin B test images and counts complexes of target-specific magnetic and fluorescent particles that have been tethered together by toxin B molecules in minimally processed stool samples. The performance characteristics of the 30 minute test include a limit of detection of 45 pg/mL, dynamic range covering 4-5 orders of magnitude, and coefficient of variation of less than 10%. The MultiPath test detected all toxinotypes and ribotypes tested, including the one most commonly occurring in the US and EU; shows no cross reactivity with relevant bacterial species; and is robust to potential interferants commonly present in stool samples. On a training set of 320 clinical stool samples, the MultiPath C. difficile toxin B test showed 97.0% sensitivity (95% CI, 91.4-99.4%); 98.3% specificity (95% CI, 96.8-99.2%); and 98.2% accuracy (95% CI, 96.7-99.0%) compared to the cellular cytotoxicity neutralization assay (CCNA) reference method. Based on these compelling performance characteristics, we believe the MultiPath technology can address the lack of rapid, sensitive, specific, and easy-to-use diagnostic tests for C. difficile.

Factors associated with an outbreak of hospital-onset, healthcare facility-associated Clostridium difficile infection (HO-HCFA CDI) in a Mexican tertiary care hospital: A case-control study

Objective

To identify clinical and environmental factors associated with an outbreak of hospital-onset, healthcare facility-associated Clostridium difficile infection (HO-HCFA CDI).

Design

Case-control study.

Setting

Public, acute care, academic tertiary referral center in Mexico.

Patients

Adults hospitalized ≥48 hours between January 2015 and December 2016 were included. Cases were patients with a first episode of HO-HCFA CDI. Controls were patients with any other diagnosis; they were randomly selected from the hospital discharge database and matched in a 1:2 manner according to the date of diagnosis of case ± 10 days. Variables with p<0.1 were considered for multivariable analysis.

Results

One hundred and fifty-five cases and 310 controls were included. Variables independently associated with HO-HCFA CDI were: exposure to both ciprofloxacin and proton pump inhibitor (PPI) within the last 3 months (OR = 8.07, 95% CI = 1.70–38.16), febrile neutropenia (OR = 4.61, 95% CI = 1.37–15.46), intraabdominal infection (OR = 2.06, 95% CI = 0.95–4.46), referral from other hospitals (OR = 1.99, 95% CI = 0.98–4.05) and an increasing number of antibiotics previously used (OR = 1.28, 95% CI = 1.13–1.46).

Conclusions

Multiple factors were found to be associated with the first episode of HO-HCFA CDI in the setting of an outbreak; of the modifiable risk factors, prior exposure to both ciprofloxacin and PPI was the most important. Referral from other hospitals was an environmental risk factor that deserves further study.

Quantitative Thresholds Enable Accurate Identification of Clostridium difficile Infection by the Luminex xTAG Gastrointestinal Pathogen Panel

Clostridium difficile colonizes the gastrointestinal (GI) tract, resulting in either asymptomatic carriage or a spectrum of diarrheal illness. If clinical suspicion for C. difficile is low, stool samples are often submitted for analysis by multiplex molecular assays capable of detecting multiple GI pathogens, and some institutions do not report this organism due to concerns for high false-positive rates. Since clinical disease correlates with organism burden and molecular assays yield quantitative data, we hypothesized that numerical cutoffs could be utilized to improve the specificity of the Luminex xTAG GI pathogen panel (GPP) for C. difficile infection. Analysis of cotested liquid stool samples (n = 1,105) identified a GPP median fluorescence intensity (MFI) value cutoff of ≥1,200 to be predictive of two-step algorithm (2-SA; 96.4% concordance) and toxin enzyme immunoassay (EIA) positivity. Application of this cutoff to a second cotested data set (n = 1,428) yielded 96.5% concordance. To determine test performance characteristics, concordant results were deemed positive or negative, and discordant results were adjudicated via chart review. Test performance characteristics for the MFI cutoff of ≥150 (standard), MFI cutoff of ≥1,200, and 2-SA were as follows (respectively): concordance, 95, 96, and 97%; sensitivity, 93, 78, and 90%; specificity, 95, 98, and 98%; positive predictive value, 67, 82, and 81%;, and negative predictive value, 99, 98, and 99%. To capture the high sensitivity for organism detection (MFI of ≥150) and high specificity for active infection (MFI of ≥1,200), we developed and applied a reporting algorithm to interpret GPP data from patients (n = 563) with clinician orders only for syndromic panel testing, thus enabling accurate reporting of C. difficile for 95% of samples (514 negative and 5 true positives) irrespective of initial clinical suspicion and without the need for additional testing.

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.

Real-world use of fidaxomicin in a large UK tertiary hospital: how effective is it for treating recurrent disease?

All courses of fidaxomicin use in the study hospital were reviewed. It was used for first recurrence (six times), second recurrence (eight times) and one case of third recurrence. One patients received fidaxomicin as first-line treatment. Eight patients initially responded to therapy; of these, three patients were asymptomatic at 90 days, three patients remained asymptomatic at 30 days, and two patients had recurrences five and nine days after stopping therapy. Four patients failed to respond; of these, two patients required faecal transplantation and one patient required a colectomy. Two patients deteriorated and two patients died. Fidaxomicin was well tolerated. These findings suggest that the utility of fidaxomicin at this stage of infection is unclear.

Primary prevention of Clostridium difficile infections with a specific probiotic combining Lactobacillus acidophilus, L. casei, and L. rhamnosus strains: assessing the evidence

Clostridium difficile infection (CDI) has become the leading healthcare-associated infection and cause of outbreaks around the world. Although various innovative treatments have been developed, preventive strategies using multi-faceted infection control programmes have not been successful in reducing CDI rates. The major risk factor for CDI is the disruption of the normally protective gastrointestinal microbiota, typically by antibiotic use. Supplementation with specific probiotics has been effective in preventing various negative outcomes, including antibiotic-associated diarrhoea and CDI. However, a consensus of which probiotic strains might prevent CDI has not been reached and meta-analyses report high degrees of heterogeneity when studies of different probiotic products are pooled together. We searched the literature for probiotics with sufficient evidence to assess clinical efficacy for the prevention of CDI and focused on one specific probiotic formulation comprised of three lactobacilli strains (Lactobacillus acidophilus CL1285, Lactobacillus casei LBC80R, Lactobacillus rhamnosus CLR2, Bio-K+) for its ability to prevent CDI in healthcare settings. A literature search on this probiotic formulation was conducted using electronic databases (PubMed, Google Scholar), abstracts from infectious disease and infection control meetings, and communications from the probiotic company. Supporting evidence was found for its mechanisms of action against CDI and that it has an excellent safety and tolerability profile. Evidence from randomized controlled trials and facility-level interventions that administer Bio-K+ show reduced incidence rates of CDI. This probiotic formulation may have a role in primary prevention of healthcare-associated CDI when administered to patients who receive antibiotics.

Bacterial diarrhea in hospitalized children: Pathogen distribution and drug resistance

AIM

To study the pathogen distribution and drug resistance in hospitalized children with bacterial diarrhea to guide the selection of appropriate antimicrobial drug regimen for the clinical treatment of bacterial diarrhea in children.

METHODS

A total of 1107 children with bacterial diarrhea treated at our hospital from May 2012 to October 2017 were retrospectively analyzed. According to the clinical data of all children (including medical records, laboratory examination results, fecal pathogen detection results, and drug susceptibility test results), the distribution and composition of pathogenic bacteria, clinical symptoms, the drug resistance of main pathogenic bacteria, therapeutic effects, and prognosis were analyzed.

RESULTS

In feces from 1107 children with bacterial diarrhea, 206 strains of pathogenic bacteria were isolated, including 39 cases of Gram-positive bacteria (such as Staphylococcus aureus) and 167 cases of Gram-negative bacteria (such as shigella, pathogenic Escherichia coli, and salmonella). The detection rate of pathogenic bacteria in the feces was the highest in children aged < 1 year, and the detection rate decreased with the increase of age. Pathogenic bacteria were detected throughout the year, especially in summer. There was a statistically significant difference (P < 0.05) in clinical symptoms (such as fever, abdominal pain, defecation, and rehydration) between bacterial diarrhea caused by Escherichia coli and Staphylococcus aureus. The rate of resistance of main Gram-positive bacteria to antimicrobial drugs moxifloxacin, vancomycin, and linezolid was less than 30%, and the rate of resistance of Gram-negative bacteria to antibiotics ceftazidime, trimethoprim/sulfamethoxazole, meropenem, and imipenem was less than 30%. The cure rate of bacterial diarrhea was 96.48% (1068/1107) after one week of treatment with antibiotics and selective antibacterial agents.

CONCLUSION

The pathogen distribution in children with bacterial diarrhea is complex, and clinicians should select antimicrobial drugs with a resistance rate less than 30% based on drug susceptibility test results.

Secular trends in the epidemiology of Clostridium difficile infection (CDI) at a tertiary care hospital in Barcelona, 2006-2015: A prospective observational study

OBJECTIVE

Describe secular trends in the epidemiology and outcome of Clostridium difficile infection (CDI) at a tertiary hospital.

METHODS

All consecutive primary CDI episodes in adults (January 2006-December 2015) were included. CDI was diagnosed on the presence of diarrhoea and a positive stool test for C. difficile toxin A and/or B. To define trends, a time-series analysis was performed using yearly data on demographics, clinical characteristics, management, antimicrobial treatment, and outcome of CDI. Patients were followed-up for three months after the diagnosis.

RESULTS

There were 724 CDI episodes. Over the period from 2006 to 2015, the incidence rose from 0.18 episodes/1000 admissions to 0.26 episodes (relative rate [RR] 1.43; 95%CI, 1.02-2.00; P = 0.035). Median Charlson comorbidity index increased from 2 (IQR 1-3) to 4 (IQR 2-4) (RR 1.65; 95%CI, 1.12-2.41; P = 0.005). Overall, 80.4% of patients received proton pump inhibitors (PPIs) prior to CDI, and the percentage of PPI discontinuations rose from 2.3% to 20.4% (RR 8.80; 95%CI 1.20-64.36; P = 0.006). Management of non-Clostridium antibiotics also changed: antibiotic withdrawals or switches increased from 4.2% to 29.2% (RR 7.00; 95%CI 1.68-29.15, P = 0.001). Regarding CDI treatment, the percentage of patients treated with metronidazole decreased (88.9% vs 52.6%) (RR 0.59 (0.48-0.73), P < 0.001), whereas the percentage receiving vancomycin increased (1.9% vs 32.6%) (RR 17.62 (2.47-125.49), P < 0.001). The percentages of cures, deaths, and first recurrences did not significantly change over the 10-year period.

CONCLUSIONS

Changes in CDI management were associated with a stable prognosis (percentage of cures and first recurrences), even though affected patients had a greater number of comorbidities over time.

Rash induced by enteral vancomycin therapy in an older patient in a long-term care ventilator unit: case report and review of the literature

BACKGROUND

Oral vancomycin is a first-line treatment for severe Clostridium difficile colitis. Oral vancomycin is perceived to lack systemic absorption or systemic adverse effects; however, a few cases of hypersensitivity to oral vancomycin have been reported, all in hospitalized patients.

CASE PRESENTATION

In the present case, a 66-year-old woman with end-stage neurodegenerative disease residing in a long-term care facility developed a maculopapular rash following treatment with enteral vancomycin for recurrent C. difficile colitis. The rash resolved after withdrawal of the drug.

CONCLUSION

Rashes associated with oral vancomycin treatment include maculopapular rash, urticaria, red man syndrome, and linear IgA bullous dermatitis. Risk factors for systemic vancomycin absorption include renal insufficiency, severe intestinal inflammation, and high vancomycin dose and duration. Routine serum testing of vancomycin levels, even in these high risk cases, is not recommended. Clinicians should be aware that enteral vancomycin can cause hypersensitivity reactions which may be serious.

The Use of Systemic and Topical Fluoroquinolones

Appropriate prescribing practices for fluoroquinolones, as well as all antimicrobial agents, are essential as evolving resistance patterns are considered, additional treatment indications are identified, and the toxicity profile of fluoroquinolones in children has become better defined. Earlier recommendations for systemic therapy remain; expanded uses of fluoroquinolones for the treatment of certain infections are outlined in this report. Prescribing clinicians should be aware of specific adverse reactions associated with fluoroquinolones, and their use in children should continue to be limited to the treatment of infections for which no safe and effective alternative exists or in situations in which oral fluoroquinolone treatment represents a reasonable alternative to parenteral antimicrobial therapy.