Diagnosis Of Clostridium Difficile Infection Research Articles

Validation of clinical risk tools for recurrent Clostridioides difficile infection.

We sought to validate available tools for predicting recurrent C. difficile infection (CDI) including recurrence risk scores (by Larrainzar-Coghen, Reveles, D'Agostino, Cobo, and Eyre et al) alongside consensus guidelines risk criteria, the leading severity score (ATLAS), and PCR cycle threshold (as marker of fecal organism burden) using electronic medical records. Retrospective cohort study validating previously described tools. Tertiary care academic hospital. Hospitalized adult patients with CDI at University of Virginia Medical Center. Risk scores were calculated within ±48 hours of index CDI diagnosis using a large retrospective cohort of 1,519 inpatient infections spanning 7 years and compared using area under the receiver operating characteristic curve (AUROC) and the DeLong test. Recurrent CDI events (defined as a repeat positive test or symptom relapse within 60 days requiring retreatment) were confirmed by clinician chart review. Reveles et al tool achieved the highest AUROC of 0.523 (and 0.537 among a subcohort of 1,230 patients with their first occurrence of CDI), which was not substantially better than other tools including the current IDSA/SHEA C. difficile guidelines or PCR cycle threshold (AUROC: 0.564), regardless of prior infection history. All tools performed poorly for predicting recurrent C. difficile infection (AUROC range: 0.488-0.564), especially among patients with a prior history of infection (AUROC range: 0.436-0.591). Future studies may benefit from considering novel biomarkers and/or higher-dimensional models that could augment or replace existing tools that underperform.

The ESCMID Study Group for Clostridioides difficile: History, Role, and Perspectives.

Clostridioides difficile (C. difficile) is a major nosocomial pathogen but is also increasingly recognised as an important diarrhoeal pathogen in the community, not always associated with antibiotics. The European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group for C. difficile (ESGCD) is a group of clinicians, scientists, and others from many European countries and further afield, who share a common interest in C. difficile. The aims of the Study Group are centred around raising the profile of C. difficile infection (CDI) in humans and animals, fostering collaboration amongst centres in different European countries and providing a forum for discussing and disseminating information. One of the principal aims of the Study Group is to raise awareness of C. difficile infections in Europe. ESGCD has a particular interest in the development and dissemination of European guidance on prevention, diagnosis, and treatment of CDI. This chapter will discuss the organisation of ESGCD within the ESCMID Study Group structure, the origins of the Study Group, the aims, and objectives of the group, and will highlight some of the past and present activities of ESGCD in relation to these.

Prevalence of Clostridium Difficile Infection (CDI) among Inflammatory Bowel Disease (IBD) Patients in Comparison to Non-IBD Patients in King Abdulaziz Medical City in Jeddah.

The prevalence of Clostridium difficile infection (CDI) as a common complication among inflammatory bowel disease (IBD) has been reported to increase worldwide and has been associated with a poor IBD outcome. In this study, our aim was to report on the prevalence of CDI among IBD vs. non-IBD patients in King Abdulaziz Medical City (KAMC). This retrospective descriptive study was carried out between 2016 and 2020. Data of 89 patients reported with CDI in KAMC were analyzed for demographics and correlations between various characteristics such as BMI, personal/family history of IBD, infection with CDI, diagnosis, method of diagnosis, and treatment modalities. Of the total 89 CDI patients, 59 (66.3%) were adults and 30 (33.7%) were pediatric, of which 36 (40.4%) were females and 53 (59.6%) were males. PCR was the main method of choice for the diagnosis of CDI (89.9%) followed by a positive-culture result (10.0%). Seventy-eight (87.6%) CDI patients were found to be immunocompromised, with two patients diagnosed with IBDs, one with UC, and one with CD. The recurrence rate was 38.4 (30 patients) among the immunocompromised group in comparison to 27.2 (3 patients) in the immunocompetent group (p=0.584). In this study, we found that adults were more prone to CDI infection, especially within hospital settings, and most of the CDI infections occurred in immunocompromised individuals, with cancer as the most common cause of it.

Clostridioides difficile infection in thoroughbred horses in Japan from 2010 to 2021

We encountered 34 Clostridioides difficile (C. difficile) infection (CDI) cases among Thoroughbred horses in Japan from 2010 to 2021. Among them, 79.4% (27/34) either died or were euthanised. The risk factors associated with CDI and mortality among Japanese Thoroughbred horses remain unclear. We used genetic methods to examine C. difficile strains and their relationships with prognosis. Twenty-two (64.7%) cases were hospitalised at the onset of colitis. Outcomes were balanced for hospitalisation rates at the onset of colitis. The mortality rates of cases treated with metronidazole (65.0%) were significantly lower than untreated cases (100%). The predominant genotype of C. difficile isolate was polymerase chain reaction ribotype (RT) 078, isolated from 12 cases (35.3%), followed by RT014 (six cases, 17.6%). Binary toxin (C. difficile transferase [CDT])-positive strains, including all RT078 strains, were isolated from 16 horses. Mortality rates in RT078 strain (75.0%) or CDT-positive strain (83.3%) cases were comparable to that in cases of other types. Sufficient infection control is needed to prevent CDI in Thoroughbred horses. A timely and prompt CDI diagnosis leading to metronidazole treatment would improve CDI outcomes.

Clostridium difficile Infection Risk Factors and Outcomes Among Inpatients Infected with NAP1/BI/027 Strain Compared to Non-NAP1 Strain in a Major Chinese Hospital

Background: NAP1/027 Clostridium difficile infection (CDI) has rarely been reported in China. Objectives: The objective of this study was to strengthen the understanding of the risk factors and outcomes of NAP1/027 CDI. Methods: A single-center, retrospective, case-control (1: 3) study was performed to identify risk factors and outcomes specific to NAP1/027 CDI using a group of patients with NAP1/027 CDI (n = 20) and a group of age-matched control patients with non-NAP1/027 CDI (n = 60) within June 2018 and August 2021. The patient charts were thoroughly reviewed to assess the markers of severity, risk factors, and outcomes. Results: Out of the 272 stool specimens, 41 cases (15.07%) tested positive for the NAP1 strain of C. difficile using the polymerase chain reaction. Among these specimens, 20 cases fulfilled the inclusion criteria. No significant difference was observed between the NAP1/027 and non-NAP1/027 groups in disease severity, length of hospital stay, or mortality. Logistic regression analysis revealed that risk factors for acquiring NAP1/027 infection included hospitalization in the 90 days before CDI diagnosis and high C-reactive protein level within ± 3 days of C. difficile detection. Conclusions: In a large non-epidemic tertiary hospital in China, NAP1/027 strains were more prevalent in patients with previous hospitalization and high CRP level than non-NAP1/027 strains.

Cover Feature: In Vitro Selection and Characterization of a DNAzyme Probe for Diverse Pathogenic Strains of Clostridium difficile (Chem. Eur. J. 36/2023)

An RNA-cleavage fluorogenic DNAzyme has been made for recognizing diverse strains of Clostridium difficile that frequently cause an infectious disease known as C. difficile infection (CDI). Upon encountering C. difficile cells, this DNAzyme cuts itself to produce a fluorescent signal, thus making it useful as a molecular probe for CDI diagnosis. This DNAzyme is highly specific as it stays silent in the presence of several control bacterial cells. The DNAzyme has an intriguing secondary structure with a pseudoknot arrangement that is essential for its functionality. More information can be found in the Research Article by Y. Li and co-workers (DOI: 10.1002/chem.202300240).

In Vitro Selection and Characterization of a DNAzyme Probe for Diverse Pathogenic Strains of Clostridium difficile.

Clostridium difficile frequently causes an infectious disease known as Clostridium difficile infection (CDI) and there are urgent needs for the development of more effective rapid diagnostic tests for CDI. Previously we have developed an RNA-cleaving fluorogenic DNAzyme (RFD) probe named RFD-CD1, which is capable of detecting a specific strain of C. difficile but is too specific to recognize other pathogenic C. difficile strains. To overcome this issue, herein we report RFD-CD2, another RFD that is not only highly specific to C. difficile but also capable of recognizing diverse pathogenic C. difficile strains. Extensive sequence and structure characterization establishes a pseudoknot structure and a significantly minimized sequence for RFD-CD2. As a fluorescence sensor, RFD-CD2 can detect C. difficile at a concentration as low as 100 CFU/mL, making this DNAzyme an attractive molecular probe for rapid diagnosis of CDI caused by diverse strains of C. difficile.

An Algorithm Addressing the Problem of Overdiagnosis of Clostridioides difficile Infections in Hematopoietic Stem Cell Transplantation Recipients: Effects on C. difficile Infection Rates and Patient Outcomes

Diarrhea of other causes and Clostridioides difficile colonization are common in patients hospitalized for hematopoietic stem cell transplantation (HSCT). It has been well recognized that these issues tend to decrease the specificity of stool testing for C. difficile infection (CDI). The best way to address this problem is uncertain. In September 2018, we initiated a project with the goal of addressing the apparent problem of overdiagnosis of CDIs in our HSCT population. Using the quality improvement tool Model for Improvement, we introduced a C. difficile stool testing and CDI diagnosis algorithm with the aim of decreasing unnecessary inpatient CDI diagnoses and treatments. In this study, we examined the effects of the algorithm. We reviewed all HSCT admissions for the 2 years before introduction of the algorithm and the subsequent 3 years, recording all stool submissions for C. difficile determination and CDI. At the close of the study, we recruited our advanced practice providers (APPs) to review all CDIs following algorithm initiation and provide feedback on the ease of use of the algorithm and potential improvements to the overall process. Stool submissions for C. difficile determination decreased from 38.0/1000 to 20.6/1000 inpatient days (P < .001) and CDI diagnoses decreased from 5.5/1000 to 2.4/1000 days (P=.007). Patients admitted for a first allogeneic HSCT, first autologous HSCT, or HSCT readmission showed similar proportionate reductions. No detrimental effects on hospital length of stay, overall survival, progression-free survival, rate of readmission post-HSCT, incidence of acute graft-versus-host disease, or incidence of recurrent CDI were noted following algorithm introduction. A strategy of education, monitoring/feedback, and ease of algorithm access proved effective in inducing provider compliance. APPs rated the algorithm high on ease of use. We conclude that the use of an algorithm defining criteria for C. difficile testing, diagnosis, and treatment was associated with significantly decreased CDI diagnoses on a HSCT inpatient unit without apparent adverse effects.

Clinical outcomes for Clostridioides difficile associated diarrhea in inflammatory bowel disease patients versus non-IBD population: A retrospective cohort study.

Patients with inflammatory bowel disease (IBD) have a higher incidence of Clostridioides difficile infection (CDI). Previous studies have demonstrated negative clinical outcomes in IBD patients with CDI compared to patients without CDI. The clinical presentation of CDI is indistinguishable from IBD exacerbation, thus posing a frequent clinical dilemma on the role of Clostridioides infection in the testing, diagnosis, and treatment of these patients. To compare clinical outcomes of CDI in patients with IBD to those without IBD. Retrospective cohort of adult patients admitted to Rabin Medical Center Israel between the years 2014 and 2020 with a concurrent diagnosis of IBD and CDI. Matching 1:2 was performed between the IBD patients and the non-IBD population with respect to age and sex. Sixty-seven patients with IBD and 134 patients without IBD were included in the study. The groups' median age was 40.6 (interquartile range [IQR] of 29.8-68.9), with 45.8% male and 54.2% female. The non-IBD group had a higher Charlson score with 2 (IQR 0; 5) versus 0 (IQR 0; 4) in the IBD group (P value <.01). Patients with IBD had more exposure to systemic antibiotics, 71.1% versus 26.3% (P value <.01). In a multivariable analysis we found no difference in 90-day mortality and rate of relapse between the 2 study groups with an odds ratio of 1.709 (95% confidence interval 0.321-9.905) and odds ratio of 0.209 (95% confidence interval 0.055-1.513) respectively. In our cohort patients with IBD who present with diarrhea and concomitant CDI have similar rates of relapse and mortality compared with patients without IBD.

Inflammatory bowel disease and Clostridium difficile infection: clinical presentation, diagnosis, and management.

As a frequent complication of inflammatory bowel disease (IBD), Clostridium difficile infection (CDI) was confirmed to not only aggravate the symptoms of IBD but also result in unexpected outcomes, including death. With the increasing prevalence rate of IBD and the updating of CDI diagnosis, the incidence of CDI in IBD patients is also seen rising. Although a detection method consisting of glutamate dehydrogenase immunoassay or nucleic acid amplification test and then toxin A/B enzyme immunoassay was recommended and widely adopted, the diagnosis of CDI in IBD is still a challenge because of the overlap between the symptoms of CDI in IBD and CDI itself. Vancomycin and fidaxomicin are the first-line therapy for CDI in IBD; however, the treatment has different effects due to the complexity of IBD patients' conditions and the choice of different treatment schemes. Although the use of fecal microbial transplantation is now in the ascendant for IBD management, the prospects are still uncertain and the prevention and treatment of the recurrence of CDI in IBD remain a clinical challenge. In this paper, the epidemiology, pathophysiology, clinical manifestation, prevention, and therapy of CDI in IBD were summarized and presented.

397. Oral Vancomycin Versus Fidaxomicin for Clostridiodes difficile: A Comparative Retrospective Evaluation across a Large, Multi-center Healthcare System

Abstract Background The Infectious Diseases Society of America and Society for Healthcare Epidemiology of America recently published the 2021 Focused Clinical Practice Guideline Update on Management of Clostridioides difficile in Adults that recommends fidaxomicin as a preferred treatment for initial and recurrent C. difficile infection (CDI) over oral vancomycin. The aim of this study was to evaluate clinical outcomes of adult inpatients with CDI diagnosis treated with fidaxomicin versus oral or rectal vancomycin. Methods The patient population included adult inpatients 18 years or older admitted to a hospital within the healthcare system with CDI International Classification of Diseases, Tenth Revision (ICD-10) codes from January 1, 2017 to October 31, 2021. Data was obtained for inpatients with a discharge diagnosis of CDI and receiving fidaxomicin, oral or rectal vancomycin, or no receipt of either antibiotic. Readmission was defined as readmittance to the healthcare system within 8 weeks and a CDI diagnosis. Recurrence risk factors were defined as age 65 years or older, immunocompromised based on ICD-10 codes, and severe CDI defined as white blood cell count &amp;gt; 15 cells/mm3 PLUS serum creatinine &amp;gt; 1.5 mg/dL. Results More than 45,000 inpatients with a CDI diagnosis were evaluated. Administration rates of vancomycin, fidaxomicin, or no receipt of either was 76%, 6% and 18%, respectively. Median length of stay for vancomycin compared to fidaxomicin was 7 versus 9 days, respectively. Readmission rate was lower for total inpatients receiving vancomycin (14.6%) compared to fidaxomicin (18.5%), showing statistical significance (p &amp;lt; 0.0000005). Subgroup analyses were performed to evaluate inpatients with risk factors for CDI recurrence. Vancomycin had a lower readmission rate for all recurrence risk factor groups. Additionally, oral vancomycin had lower readmission rates for patients with more than one risk factor (13.4% vs. 16.1%). Conclusion The results of this study demonstrated that fidaxomicin did not result in a shorter length of stay or lower readmission rate compared to oral/rectal vancomycin. This study supports the continued use of oral/rectal vancomycin for CDI without preference for fidaxomicin. Disclosures All Authors: No reported disclosures.

382. Are errors of omission falsely inflating hospital-onset Clostridioides difficile infection numbers?

Abstract Background Identification of C. difficile infection (CDI) as community onset (CO) versus hospital onset (HO) is based upon the timing of the laboratory testing. Any lab diagnosis made after day 3 of hospitalization is classified as HO-CDI, even if there is clinical evidence that the patient had CDI before lab testing was sent on day 4 or later. Capturing CDI infection early in hospitalization is essential to proper diagnosis and management of CDI. Methods This is a single center retrospective study of all HO-CDI cases identified from January 2018 through January 2022. All cases were reviewed to determine if patients had loose stools during days 1-3 which were not tested, as these may have been missed opportunities to diagnose CO-CDI. We used nursing flowsheet determine if the patient had soft, loose, watery, liquid or pasty stool bowel movements (BM). Results We identified 302 unique patients diagnosed with HO-CDI during the 4 year study period. 181 (60%) were men. The mean age 57 (range 3-98 years), with increasing case numbers with increasing age groups: age 0-18 (19/6.3%), 19-39 (39/12.9%), 40-59 (73/24.2%), ≥ 60 (171/56.6%). Mean time of HO-CDI diagnosis was 12.4 days (range 4-122 days) with a skew towards early onset HO-CDI diagnosis as 86/302 (28.5%) testing positive on days 4-6. Overall, 119/302 (39.0%) of patients had identified missed opportunities for testing stools during days 1-3 of hospitalization. 38/86 (44.2%) of patients with HO-CDI diagnosed on days 4-6 had missed opportunities for testing. 40/302 (13.2%) patients expired during the index hospitalization. Conclusion Better tracking of patients' symptoms, number and consistency of BMs could improve recognition of patients presenting with CO-CDI. In turn, this would help to institute earlier isolation and treatment of these patients, as well as decreasing HO-CDI resulting from late recognition of CO-CDI which may falsely inflate HO-CDI case numbers, and/or lead to secondary hospital transmission from delayed isolation of patients with CDI. Our findings likely represent a significant under estimation of the magnitude of the errors of omission of missing opportunities for early diagnosis of CDI since it based on review of nursing flowsheets which often miss the number and consistency of patients' BMs. Disclosures Jorge Paiva Parada, MD MPH, Shionogi: Honoraria.

2002. Clostridioides difficile Infection Recurrence Trends and Characteristics at a Community Medical Center

Abstract Background Updated IDSA C. difficile Infection (CDI) guidelines recommend fidaxomicin as preferred therapy for initial infection as studies demonstrate increased sustained response 4 weeks after the end of therapy compared with vancomycin. Implementation of this is dependent upon available resources and vancomycin is recommended as an acceptable alternative. A course of fidaxomicin costs 30-50 times more than oral vancomycin and presents a pharmacoeconomic challenge. This study evaluated the incidence and characteristics of CDI recurrence in a community medical center to assess feasibility of implementing new CDI treatment recommendations. Methods This multicenter, retrospective study was conducted at Scripps Health from 1/1/2019 - 12/31/2019. Adult patients with an initial CDI diagnosis (EIA antigen/toxin positive) were included. The primary endpoint was clinical cure, defined as no recurrent episodes of CDI one year after treatment. Secondary endpoints evaluated baseline characteristics and treatment between patients experiencing recurrence or no recurrence. Outcomes were assessed using count and proportion for descriptive data and Chi-Square, Fisher’s Exact and Logistic Regression for categorical data. Results A total of 223 patients were included, of which 18.4% (41/223) had recurrence. There was no difference in recurrence based on age &amp;gt; 65, sex, ethnicity, severity, and inpatient status (p &amp;gt; 0.05). There were no differences in comorbidities (kidney disease, cardiovascular disease, diabetes, malignancy, or pulmonary disease, p &amp;gt; 0.05) with the exception of cerebrovascular disease which was significantly higher in patients with recurrence (34.2% vs 13.2%, P = 0.001). Recurrence rates were similar between treatment groups (p = 0.383) which included vancomycin (n = 193, 20%), fidaxomicin (n = 4, 25%), metronidazole (n = 9, 0%), and vancomycin + metronidazole (n = 17, 12%). Conclusion Presence of cerebrovascular disease was the only characteristic associated with a higher incidence of CDI recurrence. The majority of patients were treated with oral vancomycin, and there was no difference in recurrence based on treatment although there were low numbers in non-vancomycin cohorts. Vancomycin is an acceptable alternative for the management of CDI in our population. Disclosures All Authors: No reported disclosures.

Melatonin as an Antimicrobial Adjuvant and Anti-Inflammatory for the Management of Recurrent Clostridioides difficile Infection.

Background:Clostridioides difficile (C. difficile) infection (CDI) is strongly associated with inflammation and has the potential to cause recurrent infections. Pre-clinical data suggest that melatonin has beneficial effects in the gastrointestinal tract due to its anti-inflammatory and antibacterial properties. This analysis examines the association between melatonin and the risk of recurrent CDI. Methods: A retrospective cohort study was conducted among patients with an inpatient diagnosis of CDI along with a positive C. difficile polymerase chain reaction (PCR) or enzyme immunoassay (EIA) test result. Patients were followed until the first study end point (death) or the first instance of recurrent infection. Propensity-score weighting was utilized accounting for confounding factors and weighted Cox models were estimated. Results: A total of 24,782 patients met the inclusion criteria, consisting of 3457 patients exposed to melatonin and 21,325 patients with no melatonin exposure. The results demonstrate that those exposed to melatonin were associated with a 21.6% lower risk of recurrent CDI compared to patients without melatonin exposure (HR = 0.784; 95% CI = 0.674-0.912). Conclusion: Our results demonstrate a decreased rate of recurrent CDI in patients exposed to melatonin. Further research on melatonin as an antimicrobial adjuvant and anti-inflammatory is warranted for the management of recurrent CDI.

Prevalence and Seasonality of Clostridiodes difficile over 12Years at a Tertiary Hospital in Brazil.

Clostridioides difficile is the main pathogen responsible for antibiotic-associated diarrhea in adults. Besides its challenging diagnosis, C. difficile infection (CDI) causes substantial morbidity and mortality. Commercially, there are assays with different targets and performances in sensitivity and specificity. The objectives of this study were to: (1) evaluate the prevalence and seasonal variability of CDI rates at a tertiary hospital in southern Brazil over 12years and (2) determine the impact of using a two-step algorithm test in the laboratory diagnosis. Between January 2007 and May 2019, fecal samples from 2275 patients were analyzed in a cross-sectional study. Four commercial tests were adopted for the diagnosis of CDI, the immunochromatographic test for toxin A from 2007 to 2010; the enzyme-linked immunosorbent assay method for toxins A and B from 2011 to March 2017; and the rapid enzyme immunoassay (EIA) for GDH and toxins A and B, associated with a Polymerase Chain Reaction (PCR) for the toxin B gene from June 2017 to 2019. The annual prevalence was 8.7% from 2007 to March 2017, increasing between June 2017 and 2019 to 14.7% when the C. diff Quik Chek Complete + GeneXpert C. difficile (two-step algorithm) test was adopted. The number of samples (691) and percentage of CDI cases (10.5%) were higher in winter, but the difference has no statistical significance (P > 0.05). An accurate diagnosis and adequate knowledge of the local seasonality of CDI allow the effective implementation of prevention and control strategies for nosocomial CDI, in addition to effective treatment for patients.

S1567 Celiac Disease Patients Have Higher Risk for Clostridium difficile Infections: A Population-Based Study

Introduction: Clostridium difficile infection (CDI) is a common gastrointestinal pathology with the incidence in the United States to 20-30 per 100 000 population. Previous studies showed association of Celiac disease and CDI, however the prevalence of CDI in patients with celiac disease has not been described in literature. Our aim is to estimate the prevalence of CDI among celiac patients, and to assess whether celiac disease is an independent risk factor for CDI. Methods: A large multi-center database (Explorys Inc., Cleveland, OH, USA) of aggregated electronic health records of 26 different healthcare systems with a total of 360 hospitals and more than 70 million patients across the United States was utilized for this study. A cohort of patients with Celiac disease was identified. Later, a second sub-cohort of those who also had CDI was identified. We excluded all the patients age < 18, patients with inflammatory bowel diseases, immunosuppressed, HIV, Roux-en-Y bypass. Statistical Package for Social Sciences (SPSS version 25, IBM Corp) was used for statistical analysis, and for all analyses, a 2-sided P-value of < 0.05 was considered statistically significant. Multivariate analysis was performed to adjust for multiple factors including age, sex, race, smoking, use of proton pump inhibitors, diagnosis of celiac disease. Results: Among the 80,884,400 individuals screened in the database there were total of 143,180 with Celiac disease (0.17%). The baseline characteristics of patients with Celiac disease are represented in Table. Celiac disease was independently associated with a higher risk of developing CDI (OR= 2.592). Other factors associated with risk of CDI included age 18-65 (OR= 2.764), White race (OR =1.880), smoking (OR= 1.540), use of proton pump inhibitors (OR= 8.468) as in the Figure. Conclusion: Celiac disease seems to be an independent risk factor for CDI. Further studies are required to investigate specifics of pathophysiology, diagnosis and treatment of CDI in patient with celiac disease.Figure 1.: Multivariable analysis for risk factors in individuals with Clostridium Difficile Infection Table 1. - Baseline Catachrestic of Study Population. Celiac disease (%)N=143,180 No celiac disease (%)N=80,741,220 Age 18-65 9,7340 (67.9) 47,893,510 (59.3) >65 39,400 (27.5) 21,266,990 (26.2) Sex Male 1,640 (1.15) 189,850 (0.24) Race Caucasian 117,430 (82.0) 42,011,260 (52.0) Comorbidities Clostridium difficile 2,050 (1.43) 231,830 (0.29) Hypertension 45,710 (31.9) 14,183,650 (17.5) Type 2 Diabetes 20,050 (13.9) 5,651,930 (6.9) Hyperlipidemia 51,170 (35.7) 11,782,380 (14.5) Smoking 19,480 (13.6) 3,874,810 (52.0) Medications PPI 54,790 (38.27) 86,37,610 (10.70)

Rapid Quantification of C. difficile Glutamate Dehydrogenase and Toxin B (TcdB) with a NanoBiT Split-Luciferase Assay.

C. difficile infection (CDI) is a leading healthcare-associated infection with a high morbidity and mortality and is a financial burden. No current standalone point-of-care test (POCT) is sufficient for the identification of true CDI over a disease-free carriage of C. difficile, so one is urgently required to ensure timely, appropriate treatment. Here, two types of binding proteins, Affimers and nanobodies, targeting two C. difficile biomarkers, glutamate dehydrogenase (GDH) and toxin B (TcdB), are combined in NanoBiT (NanoLuc Binary Technology) split-luciferase assays. The assays were optimized and their performance controlling parameters were examined. The 44 fM limit of detection (LoD), 4–5 log range and 1300-fold signal gain of the TcdB assay in buffer is the best observed for a NanoBiT assay to date. In the stool sample matrix, the GDH and TcdB assay sensitivity (LoD = 4.5 and 2 pM, respectively) and time to result (32 min) are similar to a current, commercial lateral flow POCT, but the NanoBit assay has no wash steps, detects clinically relevant TcdB over TcdA, and is quantitative. Development of the assay into a POCT may drive sensitivity further and offer an urgently needed ultrasensitive TcdB test for the rapid diagnosis of true CDI. The NanoBiTBiP (NanoBiT with Binding Proteins) system offers advantages over NanoBiT assays with antibodies as binding elements in terms of ease of production and assay performance. We expect this methodology and approach to be generally applicable to other biomarkers.

Prevalence of Clostridium difficile Infection in the Hematopoietic Transplantation Setting: Update of Systematic Review and Meta-Analysis.

Hematopoietic stem cell transplant (HSCT) recipients are vulnerable to Clostridium difficile infection (CDI) due to risk factors such as immunosuppression, antimicrobial use, and frequent hospitalization. We systematically searched PubMed and Embase to screen relevant studies from April 2014 to November 2021. A meta-analysis was performed to identify the association between CDI and hematopoietic transplantation based on the standard mean difference and 95% confidence intervals (CIs). Among the 431 retrieved citations, we obtained 43 eligible articles, which included 15,911 HSCT patients at risk. The overall estimated prevalence of CDI was 13.2%. The prevalence of CDI among the 10,685 allogeneic transplantation patients (15.3%) was significantly higher than that among the 3,840 autologous HSCT recipients (9.2%). Different incidence rates of CDI diagnosis over the last 7 years were found worldwide, of which North America (14.1%) was significantly higher than Europe (10.7%) but not significantly different from the prevalence among Asia (11.6%). Notably, we found that the estimated prevalence of CDI diagnosed by polymerase chain reaction (PCR) (17.7%) was significantly higher than that diagnosed by enzyme immunoassay (11.5%), indicating a significant discrepancy in the incidence rate of CDI owing to differences in the sensibility and specificity of the detection methods. Recurrence of CDI was found in approximately 15% of the initial patients with CDI. Furthermore, 20.3% of CDI cases were severe. CDI was found to be a common complication among HSCT recipients, displaying an evident increase in the morbidity of infection.

Standardisation and validation of an in-house quantitative real-time polymerase chain reaction (qPCR) assay for the diagnosis of Clostridioides difficile infection

ObjectivesClostridioides difficile is an emerging enteric pathogen that causes nosocomial diarrhoea in adults. The excessive cost of commercial molecular tests restricts the access of developing countries to its diagnosis. This study aimed to develop and validate in-house quantitative polymerase chain reaction (qPCR) targeting the C. difficile toxin B gene (tcdB) using two detection methodologies—SYBR Green and hydrolysis probes—for the diagnosis of C. difficile infection (CDI). MethodsGlutamate dehydrogenase (GDH) plus toxigenic culture was the standard reference diagnostic method. The SYBR Green method and hydrolysis probes were used to study 392 samples simultaneously to assess the diagnostic value of these real-time PCR assays in detecting CDI from clinical samples. ResultsThe SYBR Green and hydrolysis probe assays showed 97.9% and 87.5% sensitivity; 99.1% and 100.0% specificity; 94.0% and 100.0% positive predictive value; 99.7% and 98.3% negative predictive value; and 99.0% and 98.5% accuracy, respectively. ConclusionsThe two qPCR methodologies evaluated could offer an adequate tool as part of an algorithm in the laboratory diagnosis of CDI.

Antibiotic Resistances and Molecular Characteristics of Clostridioides difficile in ICUs in a Teaching Hospital From Central South China.

Clostridioides (C.) difficile is a major healthcare-associated pathogen inducing infectious diarrhea. Approximately 25–33% of patients with antibiotic-associated diarrhea (AAD) and 90% of patients with pseudomembranous enteritis are caused by C. difficile infection (CDI). Stool samples were collected from hospitalized adults with presumptive AAD in four nonneonatal intensive care units (ICUs). Diagnosis of CDI was based on both clinical symptoms and laboratory results. The stool specimens were transferred onto CDIF (C. difficile agar), and C. difficile was finally confirmed by the latex agglutination test. Toxin-producing genes tcdA (A), tcdB (B), and cdt (CDT) were detected by PCR, and all isolates were performed multilocus sequence typing analysis. The antibiotic susceptibility of C. difficile isolates was assessed by the agar dilution method. A total of 184 C. difficile were isolated from 857 specimens in our study, the isolation rate of C. difficile was 21.5% (184/857). The 184 C. difficile were isolated from 179 patients, among these 115 patients were toxin-positive, giving the incidence of CDI being 58.0/10,000 patient days in the four ICUs. Among these 115 toxin-positive C. difficile isolates, 100 (87.0%) isolates produced two toxins (A+B+CDT-), three (2.6%) isolates were A+B+ with binary toxin-producing (A+B+CDT+), and 12 (10.4%) isolates only produced one toxin (A-B+CDT-). A total of 27 sequencing types (STs) were obtained. The most prevalent was ST3 (34 isolates), followed by ST39 (27 isolates), ST54 (19 isolates), ST26 (16 isolates), ST35 (15 isolates), and ST2 (13 isolates). All the ST26 isolates were nontoxigenic. Meanwhile, five STs were newly discovered. Although multidrug resistance was present in ≥50% of these C. difficile isolates, all of them were susceptible to tigecycline, fidaxomicin, metronidazole, and vancomycin. In conclusion, C. difficile isolates producing two toxins (A+B+CDT-) were dominant in our hospital. The most prevalent was ST3, and all ST26 isolates were NTCD. Although multidrug resistance was present in ≥50% of the C. difficile isolates, metronidazole, tigecycline, fidaxomicin, and vancomycin were still effective treatments for CDI in our hospital.