Drug-resistant tuberculosis: a worldwide epidemic poses a new challenge.

Abstract

BACKGROUND: Although the incidence of tuberculosis (TB) in Germany is now declining, the world as a whole faces the threat of a catastrophe that will also affect the industrialized nations. The main reason, aside from TB/HIV co-infection, is the increase of resistant TB strains. The situation is already serious because of the spread of multidrug-resistant TB, i.e., TB that is resistant to the two most important antituberculous drugs, and is being further aggravated by resistance to second-line drugs as well. METHOD: Selective review of the literature. RESULTS: There are an estimated half a million cases of multidrug-resistant TB worldwide, and so-called extensively resistant TB (XDR-TB), with additional resistance to defined second-line drugs, is now prevalent in more than 45 countries. An accurate assessment of the situation is hampered by a widespread lack of laboratory capacity and/or proper surveillance. The problem is mainly due to inappropriate treatment, which may have many causes, but is theoretically avoidable. Aside from programmatic weaknesses, a lack of diagnostic and therapeutic tools causes difficulties in many countries. DISCUSSION: Only rapid and internationally concerted action, combined with intensified research efforts and the support of the affected nations, will be able to prevent the development of a situation that will no longer be manageable even with 21(st)-century technology.