CE-IVD, not approved in the US
Rapid resistance testing for proper therapy
Tuberculosis is a bacterial infection caused by species of the Mycobacterium tuberculosis (TB, MTB) complex. A drug resistant strain is defined as resistance to at least one primary drug used to treat tuberculosis. A multidrug resistant TB (MDR-TB) is defined as resistance to at least isoniazid and rifampicin, the two most effective anti-TB drugs, and an extensively drug resistant TB (XDR-TB) is defined as a MDR-TB strain with additional resistance to any fluoroquinolone and at least one injectable second-line TB drug (e.g., amikacin, kanamycin, or capreomycin). In 2017, it was estimated that >5% of incident new TB cases in the world had MDR/RR-TB. The frequency of MDR-TB varies according to region and is higher among previously treated patients.
cobas® MTB-RIF/INH for use on the cobas® 5800/6800/8800 Systems is an automated, qualitative real-time PCR test designed as a reflex test together with cobas® MTB to detect Rifampicin-resistance associated mutations of the rpoB gene and Isoniazid-resistance associated mutations in the katG and inhA genes, of M. tuberculosis. The test is intended for use on either acid-fast bacilli (AFB) smear-positive or smear-negative, raw sputum, and digested and decontaminated (N-acetyl-L-cysteine/ NaOH treated) sputum and bronchial alveolar lavage (BAL) samples, that tested positive for M. tuberculosis complex by cobas® MTB. Detection of wild-type MTB complex DNA serves as Internal Control to monitor the entire sample preparation and PCR amplification process. In addition, the test utilizes a low titer positive and a negative control.
Enabling a complete diagnosis is critical to ensure proper therapy is initiated. When patient presents with symptoms of tuberculosis, the cobas® MTB test is performed. If positive, patient should be evaluated for drug resistance using cobas® MTB-RIF/INH test. If negative, the cobas® MAI test can be used to detect a nontuberculosis infection.
cobas® MTB-RIF/INH for use on the cobas® 5800/6800/8800 Systems is an automated, qualitative in vitro diagnostic test, that utilizes real-time polymerase chain reaction (PCR), for the direct detection of rifampicin-resistance associated mutations of the rpoB gene, and isoniazid-resistance associated mutations in the katG and inhA genes, of Mycobacterium tuberculosis, from human respiratory specimens. The test is intended for use on either acid-fast bacilli (AFB) smear-positive or smear-negative, raw sputum, and digested and decontaminated (N-acetyl-L-cysteine/ NaOH treated) sputum and bronchoalveolar lavage (BAL) samples, that tested positive for Mycobacterium tuberculosis complex (MTBC) by cobas® MTB. This test is intended for use in conjunction with culture and drug susceptibility testing, and as a reflex test together with cobas® MTB, as an aid in the diagnosis of infection with a multidrug resistant M. tuberculosis (MDR-TB).
CE-IVD, not approved in the US
Access package inserts through your country’s Roche Diagnostics Website.
The ability to detect mutant MTB in a mixed infection with wild-type MTB was confirmed by testing different mutant to wild-type ratios. Low concentration levels of MDR MTB culture isolate (~3 x LoD) in a background of up to 60% wild-type MTB are detected by cobas® MTB-RIF/INH in sputum and sediment samples.
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