Tag Archives: C. diff. Laboratory Testing

A Good Question Asked By Many In the C. diff. Community; Test? Don’t Test? and HOW

C. difficile Infections

Diagnosed, Treated, then……….


Don’t Test?

and HOW



As Viewed and Published — Editorial Collaboration

Medscape &

To read article in its entirety:

Clostridium difficile Testing

Two recent studies[1,2] demonstrate the importance of appropriate selection of patients for testing for Clostridium difficile infection (CDI), as well as evaluation of performance characteristics of tests for C difficile in asymptomatically colonized patients.

C difficile is one of the most common causes of healthcare-associated infections. However, there is increasing recognition that newer nucleic acid amplification tests for C difficile may have poor specificity for true CDI while detecting patients with asymptomatic C difficile colonization.

As such, which patients to test and which tests to use are increasingly important decisions faced by hospitals, clinicians, and clinical microbiology laboratories.

Selecting Patients for Testing

The importance of appropriately selecting patients for C difficile testing is highlighted in a study by Kwon and colleagues.[1] In this study, hospitalized patients who were tested for          C difficile were characterized as having a low, medium, or high pretest probability of CDI based on clinical, laboratory, and radiologic data. Stool was tested for C difficile with toxin enzyme immunoassay (EIA) and toxigenic culture (TC).

The investigators found that nine of 111 patients had positive C difficile testing by TC, and four were positive by EIA.

Most patients had a low pretest probability (65%), although 31% had medium and 5% had high pretest probability. Of note, none of the patients with a low pretest probability had a positive EIA, although four were TC positive. Furthermore, none of the seven patients with a positive TC test but negative index EIA developed CDI within 30 days or died within 90 days after the index EIA test.

These findings emphasize the importance of appropriately selecting patients for C difficile testing, including clinical evaluation for signs and symptoms consistent with CDI, as well as alternative causes of diarrhea. A major strength of this study was that the assignment of pretest probability was based on prospective evaluation by a study physician (with interviews and physical examinations), rather than on retrospective medical record review. Given the implications for hospital surveillance, as well as potential inappropriate treatment in asymptomatically colonized patients, consideration of the pretest probability of CDI for patients in the decision to perform C difficile testing is critical.

Testing Asymptomatically Colonized Patients

Terveer and colleagues[2] evaluated the performance characteristics of C difficile tests in asymptomatically colonized patients.

The investigators compared the performance of a commercially available polymerase chain reaction (PCR) directed to toxin A and B, a commercially available enzyme-linked fluorescent assay (ELFA) to glutamate dehydrogenase (GDH), and an in-house developed PCR vs a gold standard of toxigenic culture.

Testing was performed using 765 stool samples obtained from asymptomatic patients admitted to three hospitals.

Overall, 5.1% of samples were positive for C difficile, and 3.1% contained toxigenic C difficile. The GDH ELFA and both PCR tests demonstrated high negative predictive values (>99%).

However, the positive predictive values were low (34.7% for the GDH ELFA and 31.9% for the commercially available PCR test).

The investigators commented that these performance characteristics suggest that these assays would be useful as a first screening test but that the low positive predictive values would preclude their use as stand-alone tests.


This study contributes to the literature on performance characteristics of C difficile tests in asymptomatically colonized patients, although it should be noted that the prevalence of

C difficile colonization in this cohort was somewhat lower than that reported in other studies.

TechLab C. diff. Quik Chek Complete® Antigen and Toxins A&B On A Single Device

C. difficile diagnostics

Clostridium difficile is the major cause
of nosocomial diarrhea and pseudomembranous colitis

C. difficile infection usually occurs when the normal microflora of the intestinal tract is altered or killed by antibiotics. Once C. difficile growth begins, toxins A and B are produced, causing diarrhea and colitis.

The disease can be treated with metronidazole or vancomycin, but relapses occur in about 20% of patients who develop the infection.

TECHLAB produces a panel of in vitro diagnostics for detecting C. difficile and its toxins in fecal specimens from patients suspected of having the disease.


For more information about TechLab and their products/services

click on the following link:  http://www.techlab.com/




“The C Diff Foundation’s mission is to educate and advocate for Clostridium difficile infection prevention, treatments, support, and environmental safety worldwide.
The C Diff Foundation’s organization is comprised of 100% volunteering members who are dedicated to our mission and adhere to the Foundation’s Code of Ethics
which prohibits  paid endorsements or paid promotion of products, services, medications, or clinical studies in progress.   All website entries, public presentations, and workshops are to raise C. diff. infection awareness in all areas of the C Diff Foundation’s mission statement, including infection prevention, treatments, environmental safety products, diagnostics, sepsis, healthcare-associated infections, antimicrobial resistance, antibiotic stewardship and provide education on all the above.”


June 21st Join C. diff. Spores and More #CdiffRadio Discuss the Partnership Between Laboratories and Clinical Staff For Accurate C. diff. Infection Diagnosis


Listen to the live broadcast from  June 21st,  2016

To access the live broadcast and Podcast Library
C. diff. Spores and More  Global Broadcasting Network
please click on the logo above *

C. diff. Spores and More,” Global Broadcasting Network – innovative and educational interactive healthcare talk radio program discusses

This Episode:   The Partnership Between Laboratories and Clinical Staff For the Accurate Diagnosis of a C. difficile Infection.

With Our Guests:  Dr. Steven Cagas, Ph.D.,  Dr. Nathan A. Ledeboer, Ph.D, D(ABMM),
Dr. Whitney R. Buckel, PharmD, BCPS, And  Jeanine Thomas


Learn about the importance of laboratory testing in the identification of C. difficile Infections (CDI). We will open with an interview with Jeanine Thomas, President and Founder of the MRSA Survivors Network who is a survivor of both MRSA and C. diff. infections. She will share her healthcare journey including the role that diagnostics played. Our second guest will be Nathan A. Ledeboer, PhD, D(ABMM), Medical Director of Microbiology and Molecular Diagnostics for Wisconsin Diagnostic Laboratories and Froedtert Health. He will give an overview and comparisons between various testing technologies available to clinical laboratories today. Our third guest will be Whitney R. Buckel, PharmD, BCPS who is the Infectious Diseases and Antimicrobial Stewardship Clinical Pharmacist at Intermountain Medical Center. Whitney will share with us some important details of how nurses and doctors can support the lab by taking into account the full clinical picture before sending specimens to the lab. Our last guest, Dr. Steven Cagas, will give us a brief overview of Roche Diagnostics as well as their new cobas® Cdiff Test.



Jeanine Thomas – President/ Founder of MRSA Survivors Network, National Spokesperson for MRSA, MRSA Expert and Consultant     Ms. Thomas founded MRSA Survivors Network in early 2003 due to having been critically ill with a MRSA infection, sepsis and C. difficile. Her organization was the first in the U.S. to raise the alarm about the MRSA epidemic, healthcare-acquired infections (HAI’s) and antibiotic resistance (AMR) to state and federal health officials in the U.S.   Ms. Thomas has been designated a “Patient Safety Champion” with the World Health Organizations’ World Alliance for Patient Safety (2008 – present), past member of the Joint Commission’s Patient and Family Advisory Council (2008-2010), FDA- appointed consultant on the FDA Anti-Infective Drug Advisory Committee (2008 –present) and a member of Brookings Institution’s Antibiotic Drug Development and Antimicrobial Stewardship Council (2012 –present). WHO- appointed patient representative on developing their Hand Hygiene and Antimicrobial-resistance programs for patients (2009-2012). She is a member of the Patient, Consumer and Public Health Coalition, Washington, D.C.
Dr. Nathan A. Ledeboer, PhD, D(ABMM) 

Nathan A Ledeboer is an Associate Professor of Pathology at the Medical College of Wisconsin and the Medical Director of Microbiology and Molecular Diagnostics for Wisconsin Diagnostic Laboratories and Froedtert Health.  His research endeavors, particularly in the area developing diagnostic tools for infectious diseases, have led to more than 70 publications in peer-reviewed journals and more than 100 funded research projects.
Dr. Ledeboer is also a senior editor for the Journal of Clinical Microbiology.


Dr. Whitney R. Buckel, PharmD, BCPS
Infectious Diseases/Antimicrobial Stewardship Clinical Pharmacist Intermountain Medical Center    Dr. Whitney Buckel is the Infectious Diseases/Antimicrobial Stewardship Clinical Pharmacist for Intermountain Medical Center, in Murray, Utah. She also serves as the co-chair of the Intermountain System-wide Antimicrobial Stewardship Committee, overseeing stewardship efforts across 22 hospitals. Whitney graduated from Purdue University College of Pharmacy in 2010, and completed a PGY-1 Pharmacy Practice and PGY-2 Infectious Diseases residency at The Johns Hopkins Hospital. Her research interest is in the design, implementation and outcomes of antimicrobial stewardship initiatives.


Dr. Steven Cagas, Ph.D.

Dr. Steven Cagas is a Scientific Affairs Manager within Medical and Scientific Affairs within the Molecular Diagnostics Division of Roche Diagnostics Corporation.  He has 5 years of industry experience at Roche.  He directly interfaces with clinicians and key opinion leaders to assist in the commercialization of products within the Roche Molecular Diagnostics portfolio.  He has spoken at several internal and external conferences as an invited speaker on various topics related to his areas of expertise.  Dr. Cagas received his Ph.D. in Microbiology and Molecular Genetics from the University of Medicine and Dentistry of New Jersey (currently Rutgers University).  His Ph.D. work focused on the study of the proteins expressed in the pathogenic fungus Aspergillus fumigatus.  He used a novel approach to identify the proteins expressed at various stages of development as well as in response to an antifungal agent with both studies leading to high impact publications.


C. diff. Spores and More “ Global Broadcasting Network spotlights world renowned topic experts, research scientists, healthcare professionals, organization representatives,C. diff. survivors, board members, and C Diff Foundation volunteers who are all creating positive changes in the C. diff. community worldwide.

Through their interviews, the C Diff Foundation mission will connect, educate, and empower many worldwide.

Questions received through the show page portal will be reviewed and addressed  by the show’s Medical Correspondent, Dr. Fred Zar, MD, FACP,  Dr. Fred Zar is a Professor of Clinical Medicine, Vice Head for Education in the Department of Medicine, and Program Director of the Internal Medicine Residency at the University of Illinois at Chicago.  Over the last two decades he has been a pioneer in the study of the treatment of
Clostridium difficile disease and the need to stratify patients by disease severity.

To access the C. diff. Spores and More program page and library, please click on the following link:    www.voiceamerica.com/show/2441/c-diff-spores-and-more


Take our show on the go…………..download a mobile app today


Programming for C. diff. Spores and More   is made possible through our official  Sponsor;  Clorox Healthcare