Outcomes of patients with multidrug-resistant pulmonary tuberculosis treated with ofloxacin/levofloxacin-containing regimens

Objective:To analyze outcomes of patients with multidrug-resistant tubercul osis (MDR-TB) treated with of loxacin/levofloxacin-containing regimens. Materials and methods:From February 1900 through June 1997, 63 MDR-TB patie nts (with bacillary resistance to at least isoniazid and rifampin in vitro) were analyzed retrospectively. Twenty-two patients (34.9%) had had no prev ious antituberculosis chemotherapy. Each patient received either ofloxacin (53) or levofloxacin (10) even though 13 patients had bacilli resistant to ofloxacin in The other accompanying dugs mainly included aminoglycosides, c yclosetine, ethiotlamide/prothionamide, and pyrazinamide. Sputum smear and culture examinations for acid-fast bacilli (AFB) were performed monthly for the initial 6 months and then at 2- to 3-month interviews until the end of treatment. Comparison was made between clinical successes and failures usi ng univariate and multiple logistic regression analyses for the following v ariables: age, sea, presence of cavitation, estent of disease, sputum smear positivity, in vitro resistance to ofloxacin, in vitro resistance to strep tomycin and/or ethambutol, treatment adherence, and the number of drugs per regimen. Results:Fifty-one patients (81.0%) were cured, nine patients (14.3%) failed , and three patients (4.7%) died. For the entire group, the mean duration o f treatment was 14.0 months, and the mean number of drugs was 4.7. Mean dur ations of chemotherapy in successful and failed patients were 14.5 and 14.2 months, respectively. Mean time for sputum smear and culture conversions w ere 1.7 and 2.1 months, respectively. Only cavitation, resistance to ofloxa cin, and poor adherence were found to be variables independently associated with adverse outcomes (p < 0.05; odds ratios = 15.9, 13.5, 12.8, respectiv ely). Negative sputum cultures after 2 and 3 months of therapy were 100% pr edictive of cure. Positive sputum cultures after 2 and 3 months were 52.3% and 84.6% predictive of failure, respectively. One patient (2.1%) relapsed after apparent cure. Twenty-five patients experienced adverse drug reaction s, but only 12 of them needed drug modifications. Conclusions:Most MDR-TB patients can be treated effectively with ofloxacin/ levofloxacin-containing regimens. Presence of cavitation, resistance to ofl oxacin in vitro, and poor adherence to therapy portend treatment failure. M onitoring monthly sputum culture for AFB in the initial months of chemother apy helps pl edict clinical outcomes.