Ciprofloxacin in patients with mycobacterial infections: experience in 15 patients

In vitro and animal investigations have demonstrated the antimycobacterial activity of some fluoroquinolones, including ciprofloxacin, but information regarding their clinical usefulness in mycobacterial infections is sparse. This article presents treatment results of 11 patients with tuberculosis and 4 with atypical mycobacterial infections. They were treated with combinations of ciprofloxacin and one or two other antituberculosis agents. Susceptibility of the infecting organisms to ciprofloxacin was determined in 14 of the 15 patients: in 12 of them, minimum inhibitory concentrations ranged between 0.31 and 1.25 micrograms/mL, suggesting a good level of activity. Serum concentrations of ciprofloxacin, sampled one hour after dosing and measured by a specific HPLC assay, revealed considerable variability (range 0.22-8.41 micrograms/mL). Serial plasma samples taken under controlled conditions suggested that a decreased rate of absorption was responsible for low one-hour concentrations in one of the subjects. Adverse reactions to ciprofloxacin were few and included nausea in four patients, crystalluria in one, and febrile reaction in another. A satisfactory response in terms of clinical and radiologic improvement, bacteriologic conversion, and absence of relapse was seen in 13 of the 14 patients who completed an adequate course of therapy. A controlled clinical trial of this promising antimycobacterial agent is needed.