Polydrug-resistant strains with resistance to both isoniazid and rifampicin

Resistance to both isoniazid and rifampicin, with or without resistance to other agents

Patient who has active tuberculosis with bacilli resistant at least to both rifampicin and isoniazid.

Resistance to at least isoniazid and rifampicin

Active TB in which the bacilli are resistant in vitro to at least rifampicin and isoniazid, the two most powerful first-line antiTB medicines

TB disease caused by an M. tuberculosis strain that is resistant to at least INH and rifampin. Treatment regimens for curing MDR TB are long, expensive, and difficult to tolerate. The cure rate depends on the susceptibility of M. tuberculosis to alternative chemotherapy

Resistance to at least isoniazid and rifampin, the two most important first- line drugs

Strain of M. tuberculosis is resistant to at least both isoniazid and rifampicin – and may or may not be resistant to other first-line anti-TB medicines

Mycobacterium tuberculosis complex isolates with in vitro resistance against isoniazid and rifampicin, with or without resistance to additional first-line anti-TB drug

TB that is caused by M. tuberculosis resistant to at least isoniazid (INH) and rifampin (RIF), generally requires 18–24 months of treatment after sputum culture conversion (SCC) with five or six drugs (e.g., susceptible first-line drugs plus an injectable agent, a fluoroquinolone, and other second-line drugs as needed) that are less effective, more toxic, and more costly than a standard first-line regimen

Resistance to at least Isionazid (INH) and Rifampicin (RMP), the two most potent drugs and the mainstay of anti-tuberculosis treatment

Tuberculosis in patients whose infecting isolates are resistant in vitro to at least isoniazid and rifampicin

refers to either multidrug-resistant TB (MDR-TB) or rifampicin-resistant TB (RR-TB).

TB that is resistant to isoniazid and rifampicin, the two most powerful anti-TB drugs

Resistance to at least both isoniazid and rifampicin is called MDR-TB. Treatment of MDR-TB is complicated and involves using drugs from three groups: Group A – levofloxacin or moxifloxacin, bedaquiline, linezolid; Group B – clofazimine, cycloserine or terizidone; Group C – ethambutol, delaminid, pyrazinamide, imipenem-cilastatin or meropenem, amikacin, ethionamide or prothionamide, para-aminosalicylic acid. Short regimens of 9-12 months can be used or longer regimens of 18-24 months, depending on the drug susceptibility status of the TB bacteria. Interested readers are referred to the most recent WHO Guidelines for more detailed information.

The term used in this handbook and elsewhere to group MDR-TB and RR-TB cases; both MDR-TB and RR-TB cases are eligible for treatment with MDR-TB regimens. MDR/RR-TB usually refers to all patients affected by either MDR-TB or RR-TB.

Resistance to at least isoniazid and rifampin

Defined as combined resistance to rifampicin and isoniazid, the two most important anti-TB medicines.

TB caused by Mycobacterium tuberculosis strains that are resistant to at least both isoniazid and rifampicin.

TB disease caused by a strain of M. tuberculosis complex that is resistant to rifampicin and isoniazid.

Resistance to rifampicin and isoniazid

TB caused by Mycobacterium tuberculosis strains that are resistant to at least both rifampicin and isoniazid.

Tuberculosis (TB) disease caused by bacteria resistant to two of the most important medicines – isoniazid (used to prevent TB disease in people with latent TB infection) and rifampicin (often used to treat TB disease and considered a first-line medicine).

caused by M. tuberculosis strains that are resistant to at least RIF and INH.