The basic principle of treating drug resistant TB is to use at least two drugs to which there is demonstrated susceptibility. The laboratory should test second line agents for in vitro activity. While awaiting these results, drugs the patient has not received previously should be used, including at least one injectable drug. Bactericidal drugs are preferred over bacteriostatic drugs. Patients with only resistance to isoniazid and rifampicin can be treated with pyrazinamide, ethambutol, an aminoglycoside (or capreomycin), and a fluoroquinolone. If there is ethambutol or/and pyrazinamide resistance too, the ineffective drug(s) should be dropped from this regimen and two or more of the following should be added: ethionamide, cycloserine, p-aminosalicylic acid, or a second injectable drug. Treatment efficacy and toxicity must be monitored closely, and every dose of every drug must be directly observed. Surgery may offer considerable benefit to patients in whom the bulk of disease can be resected. Medical treatment may be reduced to two or three drugs after culture conversion and continued for at least 12 more months, longer with extensive cavitary disease. Cure rates vary from <50% to >90% depending on the patient, the pattern of drug resistance, and the extent of disease.
Learning Objectives: The basic principle of treating drug resistant TB is to use at least two drugs to which there is demonstrated susceptibility. The laboratory should test second line agents for in vitro activity.
Presenting author's disclosure statement:
Organization/institution whose products or services will be discussed: None
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.