Respuesta al tratamiento antituberculosis en pacientes con historia de tratamientos previos en el Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas

background: the national institute of respiratory diseases ismael cosío villegas (iner) is a national third level referral center for all respiratory diseases, including multitreaded pulmonary tuberculosis patients (ptb). the purpose of this study was to evaluate the results of supervised ptb retreatment at the iner in patients previously treated for ptb. methods: retrospective review of clinical charts by a standardized questionary of previous treated ptb patients and whose new treatment was given and supervised al the iner from 1994 to 2001. the response was analyzed according to the number of previous treatments, history of failure to previous treatments and presence or absence of mdr ptb. results: one hundred and forty seven patients had previously received treatment for ptb. the cure rates for patients with one, two, three or more previous ptb treatments were 68.2%, 40.4%, and 8.8% (p = 0.009); desertion 6.8%, 4.3%, and 3.1% (p = 0.7); failure 18.2%, 27.7%, and 25 % (p = 0.6) for each one of the groups, respectively. the proportion of mdr- ptb was 64.4%, 86.3%, and 94.4% in each group (x2 trend, p = 0.0004). a previous treatment failure was a predictor of failure of treatment at the iner [or = 2.4 (ci95% 0.9-9.64), p = 0.04]. according to resistance, cure rates were 71.4% for one drug resistance, mdr 44.9% and poly resistance 30.8% (x2 trend, p= -03). conclusions: for patients with one or more failed previous treatments for ptb, receiving a new supervised treatment regime at the iner, there were low cure rates, a high proportion of treatment failures and a high rate of mdr-ptb.