16.3  Drug-resistant TB and multi-drug resistant TB

The emergence of resistance to anti-tuberculosis drugs, and particularly of multidrug resistant-TB (MDR-TB) arises when TB bacteria develop resistance to rifampicin and isoniazid. MDR-TB has become a major public health problem in a number of countries and an obstacle to effective global TB control. When a patient has TB with bacteria that are no longer sensitive to one or more anti-TB drugs, for instance isoniazid, using this antibiotic will not be helpful. Other drugs (known as second-line drugs) have to be used instead of the first-line drug regimens.

A good TB control programme — especially with regard to patient follow-up and adherence, will not generate much drug resistance. Resistance to TB drugs usually occurs as a consequence of inadequate treatment, be it irregular, too short or too weak. Resistant TB bacteria can be transmitted to other people like any other form of TB.

16.2.5  Prevention and management of TB among PLHIV

16.3.1  Drug sensitivity testing (DST)