The presence of drug resistance should always be suspected when there are
risk factors for it and must be confirmed by bacteriological or molecular tests for
standardized drug sensitivity. Any regimen for drug-resistant TB is more likely to be
effective if its composition is based on information from reliable drug susceptibility
testing.
The presence of drug-resistant tuberculosis should be suspected in patients who are
failing treatment, in patients with TB relapse, in subjects coming from regions with a
high prevalence of MDR-TB, and in contacts of known cases of MDR-TB. Although
there are multiple reasons why treatment may fail, the most frequent is the lack of
adherence to the regimen.
The most common causes of relapse include lack of adherence to treatment with the
development of acquired drug resistance, treatment with an inadequate therapeutic
regimen, malabsorption of drugs, and exogenous reinfection with a different strain of
M. tuberculosis.
In patients with confirmed rifampicin-susceptible and isoniazid-resistant tuberculosis,
treatment with rifampicin, ethambutol, pyrazinamide, and levofloxacin is
recommended for a duration of 6 months.
One general WHO recommendation is that all patients with rifampin-resistant TB (even
those with monoresistance to rifampin) should be treated with an MDR-TB drug
regimen. There are three options for the treatment of RR/MDR/XDR TB. Two are
recommendations for programmatic management (the short and longer regimens) and
one for operational research (the BPaL regimen).
Keywords: BPaL, Drug-resistant tuberculosis, Longer regimen, Short-course
regimen, Treatment.BPaL, Drug-resistant tuberculosis, Longer regimen, Short-course
regimen, Treatment.
