Biosite® Inc. Web Site -- Triage Qualitative -- C. difficile

What does it mean when we get a POSITIVE for the C. difficile common antigen and a NEGATIVE for Toxin A?
Look closely at the Toxin A zone when you see a C. difficile common antigen positive specimen. If this combination test result occurs, the toxin A zone may be lighter. If you see a distinct color bar, however light, it is positive. If toxin A is not detected and C. difficile common antigen is detected, then the sample contains the organism, but it had too little toxin A to be detectable or was non-toxigenic.

How do we report that? What do we tell the physicians?
Biosite recommends that you report the sample as C. difficile POSITIVE. The patient is colonized by C. difficile. The physician should reflex to clinical symptoms to determine if he/she feels treatment is appropriate. Toxin A could not be detected, but in the majority of cases when the common antigen is POSITIVE and toxin A is NEGATIVE, the patient is colonized with a truly toxigenic strain. Refer to the package insert information comparing the common antigen and cytotoxin testing with the resolved results in the brochure and package insert.

What percent of C. difficile strains are toxigenic?
Approximately 80 percent. In our study of 157 C. difficile common antigen positive specimens, 121 were proven to be toxigenic. Cytotoxin testing picked up 101 of the 121 for a sensitivity of 84 percent. The Triage C. difficile common antigen test was 98 percent sensitive for toxigenic C. difficile in the same study.

Testing for Toxin A alone is sufficient. Why do I need to test for both Toxin A and the C. difficile common antigen?
The common antigen provides unsurpassed sensitivity (98 percent sensitivity for toxigenic C. difficile vs. 84 percent for tissue culture cytotoxicity), while not cross-reacting with any other species (unlike latex products). It has long been recognized in the literature that toxin testing alone can miss up to 25 percent of true positives (16 percent for cytotoxin testing in our study – this is considered the “Gold Standard”, thus toxin A EIA’s would miss even more). You will not have this problem with the Triage C. difficile Panel.

I need to test for both toxin A and toxin B so I don’t miss anything. Why do I need to test for both toxin A and the C. difficile common antigen?
The toxins are produced by all strains (with the exception of one strain that produced only Toxin B as cited in the literature) of toxigenic C. difficile. Most test for toxin A for it is believed to cause diarrhea and other diseases as well as the fact that toxin B is very labile and degrades rapidly. This can cause false negative results in cytotoxin (toxin B) testing. Even if both toxins are destroyed, because the Triage C. difficile Panel also assays for the C. difficile common antigen you reduce false negatives markedly. Your lab results will mimic the clinical conclusions of your physicians, who believe false negatives are a distinct problem in C. difficile testing.

Is your test suitable for large batch testing?
The Triage® C. difficile Panel can be batched or run as single tests. One of our clinical trial sites has reported that they can run 15 to 20 samples in 40 to 45 minutes. Because daily controls are on board, some hospitals choose to run the samples as they come in, thus providing the most rapid turnaround time. This would not be cost effective with most other tests (i.e. microtiter accounts).

Do you have additional support services? If so, what are they and whom do I call to access them?
Biosite’s Encompass^™ program, short for Ensuring Comprehensive Assistance, is a portfolio of value added services that help our customers evaluate, implement and optimize our products as an integrated component of healthcare delivery. For more information, or to access an Encompass service, U.S. Customers should contact their local Biosite Account Executive by calling Customer Service at 1-888-BIOSITE (246-7483), ext 2.

The Encompass roster services includes:

24/7 Technical Services hotline
Training and Education: teleconferences
Evaluation support: data analysis, comparison report, technical consultation
Product training/support: technical consultants, technical services, troubleshooting
Clinical training: seminars, teleconferences
CME, CE programs available
Consulting services
CLIA audit reports, six-month mock audits, audits on request
Outcomes tracking: establishment of objectives, measurement, assessment
POC reimbursement: informational seminar, feasibility analysis, implementation
Connectivity: information management, LIS/HIS interfacing

For additional information on how Biosite can assist your institution in evolving to a point-of-care approach to diagnosis, please contact Technical Support at 1-888-BIOSITE (246-7483), ext 1.

How can I reach Technical Service if I have any product questions?
Biosite provides Technical Product Support at (888) BIOSITE (246-7483), ext. 1 and is available 24 hours per day, seven days per week. For international customers, please send your inquiries via email to techservice@biosite.com.

How do I order the Triage^® C. difficile Panel?

For U.S. hospital customers, the product can be ordered directly from HealthCare Market Division of Thermo Fisher Scientific Company. Fisher provides Customer Service (orders, invoice questions, shipping) with assistance available 24 hours per day, seven days per week. (800-640-0640), www.fishersci.com .

For U.S. physician office customers, contact one of Biosite’s authorized POL distributors: Physician Sales and Service (PSS) at (904)332-3000; Henry Schein/Caligor at (631)843-5500; HealthCare Market Division of Thermo Fisher Scientific Company at (800)640-0640.

For International customers, the product should be ordered through the assigned international distributor or Biosite sales office. Please click here for the list of Biosite sales offices and international distributors.

How will products be shipped?
Fisher will ship domestic product through dedicated logistics, small package carriers (UPS, Fedex, etc) and LTL carriers. The product characteristics and customer requirements are utilized to determine “best way” routing and delivery method.

How can I request a copy of the Quick Reference Guide?
Please call Technical Product Support at (888) BIOSITE (888-246-7483), available 24 hours per day, 7 days per week. For international customers, please send your inquiries via email to techservice@biosite.com.

How do I contact my Biosite Account Executive?
You may call Customer Support at 1-888-246-7483, ext. 2.