FDA Clears Test to Help Determine Whether TB Patients Can Be Removed From Isolation
Cepheid has received expanded Food and Drug Administration (FDA) clearance for its Xpert MTB/RIF assay, which has now been authorized to help physicians determine if patients with suspected tuberculosis (TB) can be removed from an airborne infection isolation room. The Centers for Disease Control and Prevention (CDC) recommends keeping a patient suspected of having active TB isolated until clinical and laboratory information—including acid-fast bacilli (AFB) smear testing of three sputum specimens, each collected 8 to 24 hours apart—shows that the patient is unlikely to have contagious TB. The MTB/RIF test is a nucleic acid amplification test that, unlike a smear test, detects the DNA of the mycobacterium that causes TB. This enables the MTB/RIF test to detect TB even when the smear test may be negative. Due to the MTB/RIF test’s higher accuracy, healthcare providers only need one or two test results, as opposed to three, to help them decide whether to keep patients in isolation.
CDC cautions that the MTB/RIF test may not detect all patients with active TB, however, so it is important that healthcare workers also continue to follow current CDC guidelines to collect consecutive sputum specimens for TB culture testing, even if results from MTB/RIF testing are negative.
Becomes First NGS System
to Win Approval in Canada
Illumina has received regulatory approval from Health Canada for the MiSeqDx instrument, the MiSeqDx Cystic Fibrosis 139-Variant assay, and the MiSeqDx Cystic Fibrosis Clinical Sequencing assay. The approval is the first for a next-generation sequencing system in Canada, and follows the U.S. Food and Drug Administration’s clearance of the system and assays in late 2013.
Designed and validated for the clinical market, the MiSeqDx instrument and its portfolio of tests use Illumina’s sequencing by synthesis chemistry. The MiSeqDx Cystic Fibrosis 139-Variant assay is designed for the simultaneous detection of 139 clinically relevant disease-causing mutations and variants within the cystic fibrosis transmembrane conductance regulator (CFTR) gene. These include all of the cystic fibrosis-causing variants recommended for carrier screening purposes by the American College of Medical Genetics and Genomics and referenced by the Canadian College of Medical Geneticists, as well as many additional disease causing variants occurring in multiple ethnic sub-groups. The second kit approved for use on the MiSeqDx instrument, the MiSeqDx Cystic Fibrosis Clinical Sequencing assay, provides sequencing data for the protein coding regions and intron/exon boundaries of the CFTR gene.
FDA Can Now Issue Emergency Use Authorizations for Enterovirus D68 Tests
Secretary of Health and Human Services Sylvia Burwell has determined that there is a significant potential for enterovirus D68 (EV-D68)—the recent cause of a nationwide outbreak of severe respiratory illness—to cause a public health emergency in the U.S. Burwell has declared that circumstances exist justifying the authorization of emergency use of new in vitro diagnostics for detection of EV-D68. Acting under this declaration, the Food and Drug Administration will now be able to quickly review EV-D68 diagnostics and authorize their use without taking them through the standard 510(k) clearance or premarket approval process.
Enteroviruses are very common and typically only cause mild illness, like the common cold. From mid-August 2014 to mid-January 2015, however, the Centers for Disease Control and Prevention and state public health laboratories confirmed a total of 1,153 people in 49 states and the District of Columbia with respiratory illness caused by EV-D68, 14 of whom died.