Is a Two-Step Glutamate Dehyrogenase Antigen-Cytotoxicity Neutralization Assay Algorithm Superior to the Premier Toxin A and B Enzyme Immunoassay for Laboratory Detection of Clostridium difficile?

Clinical Microbiology-Immunology Laboratories, UNC Hospitals, CB 7600, Chapel Hill, NC 27514, USA.
Journal of clinical microbiology (Impact Factor: 3.99). 05/2008; 46(4):1523-5. DOI: 10.1128/JCM.02100-07
Source: PubMed


A two-step algorithm for the detection of Clostridium difficile by the use of C. Diff Quik Chek (TechLab, Blacksburg, VA) and a tissue culture cytotoxicity neutralization assay was found
to be more sensitive than the widely used solid-phase enzyme immunoassay (EIA), the Premier toxin A and B EIA (Meridian Bioscience,
Cincinnati, OH), and a newly developed, rapid single-test EIA for C. difficile toxins A and B (Tox A/B Quik Chek; TechLab).

4 Reads
  • Source
    • "Our data support the findings of Eastwood et al. suggesting an important role of molecular detection of CDI in the future. A number of studies have used two-or three step approaches for the diagnosis of CDI (Fenner et al., 2008; Gilligan, 2008; Kvach et al., 2009; Sharp et al., 2009; Shin et al., 2009). Our screening PCR would provide an excellent first step with a very high NPV. "
    [Show abstract] [Hide abstract]
    ABSTRACT: We have developed and validated a rapid molecular screening protocol for toxigenic Clostridium difficile, that also enables the identification of the hypervirulent epidemic 027/NAP1 strain. We describe a multiplex real-time PCR assay, which detects the presence of the tcdA and tcdB genes directly in stool samples. In case of positive PCR results, a separate multiplex real-time PCR typing assay was performed targeting the tcdC gene frame shift mutation at position 117. We prospectively compared the results of the screening PCR with those of a cytotoxicity assay (CTA), and a rapid immuno-enzyme assay for 161 stool samples with a specific request for diagnosis of C. difficile infection (CDI). A total of 16 stool samples were positive by CTA. The screening PCR assay confirmed all 16 samples, and gave a PCR positive signal in eight additional samples. The typing PCR assay detected the tcdC Δ117 mutation in 2/24 samples suggesting the presence of the epidemic strain in these samples. This was confirmed by PCR ribotyping and sequencing of the tcdC gene. Using CTA as the "gold standard", the sensitivity, specificity, positive predictive value, and negative predictive value, for the screening PCR were 100%, 94.4%, 66.7%, and 100%, respectively. In conclusion, PCR may serve as a rapid negative screening assay for patients suspected of having CDI, although the low PPV hamper the use of PCR as a standalone test. However, PCR results may provide valuable information for patient management and minimising the spread of the epidemic 027/NAP1 strain.
    Journal of microbiological methods 10/2010; 83(1):59-65. DOI:10.1016/j.mimet.2010.07.017 · 2.03 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Not Available
    Antennas and Propagation Society International Symposium, 1963; 08/1963
  • [Show abstract] [Hide abstract]
    ABSTRACT: We have previously reported that a large E times B rotational electron current circles the inside of the anode in the cold cathode Penning discharge and that this current is unstable as a consequence of the diocotron effect. We have observed that by splitting the anode, it is possible to couple effectively to the space charge bunches which result from the instability. The output obtained in this way, consists of short bursts of radiation. The radiation frequency centers around the E times B rotation frequency of the electrons, but varies substantially during each burst. We have made use of this random radiation pattern and have developed a high power noise generator. Our present prototypes deliver noise powers in excess of 20 watts at an efficiency of up to 25% in the UHF region of the spectrum. The noise spectrum is voltage tuneable, and the band width, which is electronically rather than circuit limited, is approximately 10%.
    Electron Devices Meeting, 1964 International; 02/1964
Show more


4 Reads
Available from