[Therapy and prognosis of tuberculosis]

Treatment and prognosis of tuberculosis. Worldwide the so-called short-course chemotherapy has become the standard treatment for tuberculosis. The 6-month regimen consists of isoniazid, rifampin, and pyrazinamid given for 2 month followed by isoniazid and rifampin for 4 month. Ethambutol or streptomycin is added in the first 2 month in patients with advanced disease. This recommendation applies to both HIV-infected and uninfected persons. The major determinant of the outcome of treatment is patient adherence to the drug regimen. In susceptible strains the success rate with the 6-month regimen in sputum conversion is far beyond 90% within the first two month of therapy. The relapse rate after 3 to 5 years is about 0-3%. Multiple-drug-resistant tuberculosis (i.e., resistance to at least two drugs) presents difficult treatment problems. Treatment must be individualized and based on susceptibility studies. For patients with tuberculosis that is resistant to rifampin and isoniazid, even the best available treatment is often unsuccessful. The role of new agents such as the quinolone derivatives and amikacin in the treatment of multidrug-resistant disease is not known, although these drugs are commonly being used in such cases.