A retrospective study of the addition of ciprofloxacin to clarithromycin and ethambutol in the treatment of disseminated Mycobacterium avium complex infection

Disseminated Mycobacterium avium complex (DMAC) infection is associated wit h increased morbidity and mortality in HIV-infected individuals. The combin ation antibiotic regimens containing clarithromycin can decrease symptoms a nd improve survival in patients with DMAC, however, optimal therapy remains to be defined. Quinolones have been widely used in the treatment of DMAC b ut their utility has not been established. A retrospective cohort study of DMAC infection was established in a metropo litan hospital providing comprehensive care to over 3000 HIV-infected indiv iduals. Medical records of patients with DMAC diagnosed at the Parkland Mem orial Hospital from 1991 to 1994 were reviewed for therapeutic regimens for DMAC, concomitant therapy for HIV and Pneumocystis carinii prophylaxis and date of death. Subjects were included if they were treated with clarithrom ycin and ethambutol. Cases were defined as those patients who received more than 30 days of ciprofloxacin as therapy for DMAC in addition to the other drugs that they received. The primary endpoint was the time to death from the data of DMAC diagnosis. Covariates effecting survival were analysed thr ough the Cox proportional hazards model. Eighty-nine subjects with DMAC who were treated with clarithromycin and eth ambutol were identified. Fifty-eight received ciprofloxacin in addition to clarithromycin and ethambutol. The time to death was significantly better i n those subjects who were treated with ciprofloxacin than those who were no t (489 days vs 281 days, P=0.01). The sole significant predictor of improve d survival on Cox proportional hazards model was ciprofloxacin therapy. Subjects treated with combination of clarithromycin, ethambutol and ciprofl oxacin had improved survival over those treated with clarithromycin and eth ambutol alone.