Concentrations of moxifloxacin in serum and pulmonary compartments following a single 400 mg oral dose in patients undergoing fibre-optic bronchoscopy

The concentrations of moxifloxacin achieved after a single 400 mg dose were measured in serum, epithelial lining fluid (ELF), alveolar macrophages (AM) and bronchial mucosa (BM). Concentrations were determined using a microbiological assay. Nineteen patients undergoing fibre-optic bronchoscopy were studied. Mean serum, ELF, AM and BM concentrations at 2.2, 12 and 24 h were as follows: 2.2 h: 3.2 mg/L, 20.7 mg/L, 56.7 mg/L, 5.4 mg/kg; 12 h: 1.1 mg/L, 5.9 mg/L, 54.1 mg/L, 2.0 mg/kg; 24 h: 0.5 mg/L, 3.6 mg/L, 35.9 mg/L, 1.1 mg/kg, respectively. These concentrations exceed the MIC(90)s for common respiratory pathogens such as Streptococcus pneumoniae (0.25 mg/L), Haemophilus influenzae (0.03 mg/L), Moraxella catarrhalis (0.12 mg/L), Chlamydia pneumoniae (0.12 mg/L) and Mycoplasma pneumoniae (0. 12 mg/L) and indicate that moxifloxacin should be effective in the treatment of community-acquired, lower respiratory tract infections.