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First Molecular Diagnostic Test for <i>Clostridium difficile</i> Infection Approved
"The previous lack of an accurate and rapid diagnostic test for CDI has greatly impeded our ability to halt the increasing rate of CDI, which has taken a severe turn in the past several years. Patients can have their first diarrhea symptoms on a Monday and be dead by Thursday," said Dale Gerding, MD, professor of medicine, division of infectious diseases, Loyola University Chicago Stritch School of Medicine. "Toxigenic culture offers high sensitivity, but laboratories find it burdensome and far too slow for practical diagnostic use. Instead, many use less labor-intensive toxin EIA (enzyme immunoassay) and GDH (glutamate dehydrogenase) tests, which fail to detect 20-50% of cases. From a practical standpoint, this means many patients are not subjected to proper isolation procedures that can curtail transmission of C. difficile. A rapid, accurate CDI test will eliminate needless repetitive testing and enable us to implement appropriate treatment and infection control measures faster in our battle against this devastating Healthcare Associated Infection."
C. difficile, a spore-forming bacterium, is now challenging Methicillin-resistant Staphylococcus aureus (MRSA) as the most prevalent Healthcare Associated Infection (HAI) in the United States. A recent study published by the Association for Professionals in Infection Control and Epidemiology (APIC) found that on any given day there are more than 7,000 patients in the United States suffering from CDI, causing the deaths of approximately 300 patients per day. The disease, which can range in severity from mild to severe diarrhea, pseudomembranous colitis, toxic megacolon, sepsis, and death, is costing American healthcare institutions up to $51.5 million per day.
"As the leader in molecular HAI testing, it is incumbent for Cepheid to provide healthcare institutions access to the most comprehensive suite of rapid and accurate HAI tests on the market. The Xpert C. difficile test establishes new levels of speed, accuracy, and ease-of-use for CDI testing," said John Bishop, Cepheid's Chief Executive Officer. "As Cepheid continues the development of innovative new diagnostic solutions, we will strive to measure our product design against a solid understanding of healthcare's current, and future, needs for rapid and accurate diagnostic tests. Our novel approach for the Xpert C. difficile test, as measured against the true gold standard of toxigenic culture, delivered on that vision."
As CDI rates continue to rise throughout the world, a more virulent epidemic strain, known as 027/NAP1/BI, has now been detected in at least 48 states, Canada, and throughout Europe. The Xpert C. difficile test has been cleared for the direct detection of toxigenic Clostridium difficile from stool specimens. The test targets the Toxin B gene, discovered in 1978 to be the cause of antibiotic-associated diarrhea and colitis. The Toxin B (tcdB) gene is the critical component of all toxigenic Clostridium difficile strains -- including the epidemic 027/NAP1/BI strain. Cepheid will also continue to work closely with the FDA to deliver an additional product featuring simultaneous differentiation of the 027/NAP1/BI epidemic strain.
The Xpert C. difficile test is Cepheid's seventh test to receive FDA clearance, and fourth in its expanding menu of on-demand HAI products. The test, which runs on Cepheid's GeneXpert® System, will be available for shipment the week of July 20th.
About the GeneXpert System
The GeneXpert System is a closed, self-contained, fully-integrated and automated platform that represents a paradigm shift in the automation of molecular analysis, producing accurate results in a timely manner with minimal risk of contamination. The GeneXpert System is the only system to combine on-board sample preparation with real-time PCR (polymerase chain reaction) amplification and detection functions for fully integrated and automated nucleic acid analysis. The system is designed to purify, concentrate, detect and identify targeted nucleic acid sequences thereby delivering answers directly from unprocessed samples. Modular in design, the GeneXpert System has a variety of configurations to meet the broad range of testing demands of any clinical environment.