RETREATMENT TUBERCULOSIS CASES - FACTORS ASSOCIATED WITH DRUG-RESISTANCE AND ADVERSE OUTCOMES

Study objective: Risk factors associated with treatment failure and mu ltidrug-resistant tuberculosis (MDR-TB) were examined among HIV-serone gative patients who were previously treated for tuberculosis (TB). Des ign: Prospective, cohort study of patients referred to the study hospi tal for retreatment of TB between March 1986 and March 1990. Patients: The patients belonged to three groups, according to outcomes followin g their previous treatment: 37 patients who abandoned treatment car su ffered release after completion of therapy (group A), 91 patients who failed to respond to the first-line drug regimen (group B), and 78 pat ients who failed to respond to the second-line drug regimen (group C), Results: Patients with Mycobacterium tuberculosis strains resistant t o rifampin and isoniazid were found in 2 (6%) in group A, 29 (33%) in group B, and 49 (65%) in group C, Cure was achieved in 77% in group A, 54% in group B, and 36% in group C. Death occurred in none of the pat ients in group A, 8% in group B, and 24% in group C. Inn a multivariat e logistic regression analysis, unfavorable response (failure to steri lize sputum culture, death, and abandonment) was significantly associa ted with infection with a multidrug-resistant M tuberculosis strain (p = 0.0002), cavitary disease (p = 0.0029), or irregular use of medicat ions (p < 0.0001). Conclusion: These observations show that a previous treatment outcome and current clinical and epidemiologic histories ca n be used to predict the development of MDR-TB and adverse outcomes in patients undergoing retreatment for TB. Such information may be usefu l for identifying appropriate patient candidates for programs such as directly observed therapy.