scholarly journals Evaluation of LIAISON® C. difficile glutamate dehydrogenase and LIAISON® C. difficile toxin A and B in Copan FecalSwabTM samples in a three-step algorithm for the diagnosis of Clostridium difficile infection

2015 ◽  
Vol 30 (1) ◽  
Author(s):  
Massimo Oggioni ◽  
Alessandra Bielli ◽  
Alice Nava ◽  
Daniela Adele Pia Campisi
Keyword(s):  
Clostridium Difficile ◽  
Glutamate Dehydrogenase ◽  
Laboratory Diagnosis ◽  
Binary Toxin ◽  
Common Antigen ◽  
Molecular Test ◽  
Toxin A ◽  
Large Numbers ◽  
Step Algorithm ◽  
Short Time

The presumptive laboratory diagnosis of <em>Clostridium</em> <em>difficile</em> infection is achieved by the means of the detection of a common antigen (glutamate dehydrogenase, GDH) in stool, then confirming the positives either by the detection of toxins A and B or by a molecular test for the detection of pathogenicity <em>locus</em>, encoding for the two toxins and for the binary toxin. A fully automated chemiluminescence system for the GDH antigen (LIAISON® C. difficile GDH) and for the detection of toxins A and B (LIAISON® C. difficile Toxin A and B) (DiaSorin, Gerenzano, Italy) allows for the performance of these tests on large numbers of samples in a short time, ensuring the traceability of the data.

scholarly journals Infection with Toxin A-Negative, Toxin B-Negative, Binary Toxin-Positive Clostridium difficile in a Young Patient with Ulcerative Colitis

2015 ◽  
Vol 53 (11) ◽  
pp. 3702-3704 ◽  
Author(s):  
Grace O. Androga ◽  
Julie Hart ◽  
Niki F. Foster ◽  
Adrian Charles ◽  
David Forbes ◽  
...  
Keyword(s):  
Ulcerative Colitis ◽  
Clostridium Difficile ◽  
Young Patient ◽  
Diagnostic Methods ◽  
Binary Toxin ◽  
Toxin A ◽  
Toxin B ◽  
Content Type ◽  
Severe Diarrhea ◽  
Clinically Significant

Large clostridial toxin-negative, binary toxin-positive (A−B−CDT+) strains ofClostridium difficileare almost never associated with clinically significantC. difficileinfection (CDI), possibly because such strains are not detected by most diagnostic methods. We report the isolation of an A−B−CDT+ribotype 033 (RT033) strain ofC. difficilefrom a young patient with ulcerative colitis and severe diarrhea.

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

2018 ◽  
Vol 56 (8) ◽  
Author(s):  
Alice Banz ◽  
Aude Lantz ◽  
Brigitte Riou ◽  
Agnès Foussadier ◽  
Mark Miller ◽  
...  
Keyword(s):  
Clostridium Difficile ◽  
Single Molecule ◽  
Laboratory Diagnosis ◽  
Case Definition ◽  
Cell Cytotoxicity ◽  
Toxin A ◽  
Toxin B ◽  
Content Type ◽  
High Performing ◽  
Molecular Tests

ABSTRACT 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.

scholarly journals Combination of Culture, Antigen and Toxin Detection, and Cytotoxin Neutralization Assay for OptimalClostridium difficileDiagnostic Testing

2013 ◽  
Vol 24 (2) ◽  
pp. 89-92 ◽  
Author(s):  
Michelle J Alfa ◽  
Shadi Sepehri
Keyword(s):  
Diagnostic Algorithm ◽  
Laboratory Diagnosis ◽  
Neutralization Assay ◽  
Confirmatory Test ◽  
Toxin A ◽  
Diagnostic Laboratory ◽  
Toxigenic Culture ◽  
Stool Samples ◽  
Step Algorithm ◽  
One Year

BACKGROUND: There has been a growing interest in developing an appropriate laboratory diagnostic algorithm forClostridium difficile, mainly as a result of increases in both the number and severity of cases ofC difficileinfection in the past decade. AC difficilediagnostic algorithm is necessary because diagnostic kits, mostly for the detection of toxins A and B or glutamate dehydrogenase (GDH) antigen, are not sufficient as stand-alone assays for optimal diagnosis ofC difficileinfection. In addition, conventional reference methods forC difficiledetection (eg, toxigenic culture and cytotoxin neutralization [CTN] assays) are not routinely practiced in diagnostic laboratory settings.OBJECTIVE: To review the four-step algorithm used at Diagnostic Services of Manitoba sites for the laboratory diagnosis of toxigenicC difficile.RESULT: One year of retrospectiveC difficiledata using the proposed algorithm was reported. Of 5695 stool samples tested, 9.1% (n=517) had toxigenicC difficile. Sixty per cent (310 of 517) of toxigenicC difficilestools were detected following the first two steps of the algorithm. CTN confirmation of GDH-positive, toxin A- and B-negative assays resulted in detection of an additional 37.7% (198 of 517) of toxigenicC difficile. Culture of the third specimen, from patients who had two previous negative specimens, detected an additional 2.32% (12 of 517) of toxigenicC difficilesamples.DISCUSSION: Using GDH antigen as the screening and toxin A and B as confirmatory test forC difficile, 85% of specimens were reported negative or positive within 4 h. Without CTN confirmation for GDH antigen and toxin A and B discordant results, 37% (195 of 517) of toxigenicC difficilestools would have been missed. Following the algorithm, culture was needed for only 2.72% of all specimens submitted forC difficiletesting.CONCLUSION: The overview of the data illustrated the significance of each stage of this four-stepC difficilealgorithm and emphasized the value of using CTN assay and culture as parts of an algorithm that ensures accurate diagnosis of toxigenicC difficile.

Equine Colitis X Associated with Infection by Clostridium Difficile NAP1/027

2009 ◽  
Vol 21 (3) ◽  
pp. 377-380 ◽  
Author(s):  
J. Glenn Songer ◽  
H. T. Trinh ◽  
Sharon M. Dial ◽  
Jon S. Brazier ◽  
Robert D. Glock
Keyword(s):  
Clostridium Difficile ◽  
Mononuclear Cells ◽  
Intestinal Wall ◽  
Negative Regulator ◽  
Binary Toxin ◽  
Large Numbers ◽  
History Of ◽  
Polymerase Chain ◽  
Mucosal Lamina Propria

A 14-year-old Quarter Horse with a 48-hr history of colic was euthanized after failure to respond to treatment. At necropsy, cecal and colonic mucosae were congested throughout, and there was segmental edema and significant thickening of the intestinal wall. Excessive numbers of mononuclear cells were found in mucosal lamina propria. Submucosal hemorrhage was diffuse and extensive, and Clostridium difficile toxins A and B were detected. Large numbers of C. difficile were isolated, and genetic characterization revealed them to be North American pulsed-field gel electrophoresis type 1, polymerase chain reaction ribotype 027, and toxinotype III. Genes for the binary toxin were present, and toxin negative–regulator tcdC contained an 18-bp deletion. This genotype comprises the current human “epidemic strain,” which is associated with human C. difficile–associated disease of greater than historical severity. The diagnosis was peracute typhlocolitis, with lesions and history typical of those attributed to colitis X.

scholarly journals Increasing Prevalence of Toxin A-Negative, Toxin B-Positive Isolates of Clostridium difficile in Korea: Impact on Laboratory Diagnosis

2008 ◽  
Vol 46 (3) ◽  
pp. 1116-1117 ◽  
Author(s):  
H. Kim ◽  
T. V. Riley ◽  
M. Kim ◽  
C. K. Kim ◽  
D. Yong ◽  
...  
Keyword(s):  
Clostridium Difficile ◽  
Laboratory Diagnosis ◽  
Toxin A ◽  
Toxin B
Sign in / Sign up

Export Citation Format

Share Document