[Sputum penetration of levofloxacin and its clinical efficacy in patients with chronic lower respiratory tract infections].

Sputum penetration of levofloxacin (LVFX) was evaluated after a single oral dose of 100 mg or 200 mg to 4 patients with copious purulent sputa. The sputum concentration of LVFX reached maximum levels of 1.27 and 4.36 micrograms/ml at 4 hours, and still remained at concentrations of 0.32 and 1.68 micrograms/ml at 8 hours after administration of 100 mg and 200 mg, respectively. The AUC ratio of sputum/serum was 0.9-1.0, indicating good sputum penetration of LVFX in these patients. The clinical efficacy and the safety of LVFX were also evaluated in a total of 13 patients with respiratory tract infections associated with bronchiectasis, diffuse panbronchiolitis, etc. LVFX was administered orally at a daily dose of 200 mg once a day, 100 mg t.i.d. or 200 mg t.i.d. for 7-28 days (mean 14.7 days). The clinical response to the drug was rated as excellent in 1 case, good in 5, fair in 3, and poor in 2 cases in 11 evaluable cases, thus the efficacy rate was 54.5%. All the 3 strains of Haemophilus influenzae were eradicated. Of the 3 strains of Pseudomonas aeruginosa, eradication, decrease, and unchange was observed for 1 strain each. One strain of Streptococcus pneumoniae remained unchanged. No adverse reaction was observed except for 1 case with slight and temporary increase of eosinophils. The above results suggested that LVFX would be clinically useful in the treatment of chronic lower respiratory tract infections.