New Test Detecting Diarrhea-Causing Infection

FDA approves test identifying genes associated with Clostridium difficile infection

/ Author:  / Reviewed by: Joseph V. Madia, MD

The FDA has approved a test that detects an infection that causes diarrhea, other intestinal problems and sometimes death.

The FDA has cleared a test called the Cepheid Xpert C. difficile/Epi assay that is designed to rapidly detect the toxin B gene associated with Clostridium difficile infection (CDI), a cause of diarrhea that can lead to colitis, other serious intestinal conditions and death in severe cases.

Clostridium difficile (C. difficile) bacteria are found in the stool of an infected person. Others can become infected if they touch items or surfaces contaminated with the bacteria or spores and then touch their mouth.

The Cepheid Xpert C. difficile/Epi assay is automated and works on the Cepheid GeneXpert Dx System to detect toxin gene sequences associated with toxigenic C. difficile.

The Cepheid GeneXpert Dx System consists of an instrument that houses single-use disposable cartridges, a personal computer, and software that allow a laboratory technician to run tests and view test results quickly.

The test, Cepheid Xpert C. difficile/Epi assay, determines if C. difficile is in a patient’s stool and also detects if the C. difficile is the epidemic 027/NAP1/BI strain, which has been associated with a marked increase in the severity and incidence of CDI in North America and Europe over the past decade.

The test is intended for use as an aid in the diagnosis of CDI. The detection of the 027/NAP1/B1 strain is for epidemiological purposes only and should not be used to determine or monitor treatment.

Healthcare facilities should monitor the number of C. difficile infections and, especially if rates at the facility increase, the severity of disease and patient outcomes.

“Health care professionals in the infectious disease community who have seen various outbreaks of CDI associated with aggressive strains in recent years now have a new testing tool to detect this disease,” said Alberto Gutierrez, Ph.D., director of the Office of In Vitro Diagnostics Device Evaluation and Safety in the FDA’s Center for Devices and Radiological Health.

People at risk of developing the bacterial infection include the elderly, patients in hospitals or living in a nursing home, and people taking antibiotics for another infection. The most effective way to prevent CDI is thorough handwashing with soap and warm water.

The Cepheid Xpert C. difficile/Epi test is made by Cepheid of Sunnyvale, Calif.

Review Date: 
April 11, 2011