[Diffusion of an orally administered single dose of ofloxacin into human bronchial mucus]. / Diffusion de l'ofloxacine administrée à une dose unique par voie orale dans le mucus bronchique chez l'homme.

As part of a systematic investigation of the penetration of antibiotics into human bronchial mucus, we assayed ofloxacin concentrations following ingestion of a single dose. 25 patients with acute superinfection of a chronic lower respiratory tract disease were studied. Each patient had single drug therapy with ofloxacin in a daily dosage of 200 mg taken in the morning on an empty stomach. Patients were divided into five groups according to the time interval between ingestion of ofloxacin and collection of samples (bronchial mucus and serum): 1 hour, 3 hours, 6 hours, 12 hours or 24 hours. Duplicate determinations of ofloxacin on individual samples were done using a microbiologic method. Mean serum concentrations were 1.85, 1.64, 1.32, 0.75 and 0.20 mg/l respectively, with a half-life of 6.7 hours; the corresponding concentrations in mucus were 1.83, 1.51, 1.20, 0.66 and 0.19. These results demonstrate ofloxacin's outstanding penetration into bronchial mucus.

[Aztreonam. Diffusion into bronchial mucus]. / Aztréonam. Diffusion dans le mucus bronchique.

In a prospective study of antibiotics' diffusion into human bronchial mucus, we compared serum and mucus concentrations of aztreonam, a new beta lactam belonging to the monobactam group. Twenty patients were given aztreonam (1 g twice a day) for an acute purulent exacerbation of chronic bronchitis and divided into four groups according to the time of sampling (0.5, 1, 1.5 or 3 h). Samples were taken on the first and third treatment days. Antibiotic concentrations were assayed using agar diffusion and HPLC. Aztreonam concentrations were low, similar to those achieved with other beta lactams. According to the time sampling, levels ranged from 0.27 to 1 mg/l and 0.4 to 1.15 mg/l on the first and third treatment days respectively. Corresponding serum levels were 90 mg/l and 30 mg/l, respectively 30 mn and 3 h after dose ingestion.

Penetration of cefotaxime into bronchial secretions.

The penetration into bronchial secretions of cefotaxime, a new, highly active cephalosporin, was studied in 45 patients with respiratory infections. Ten patients received 0.75 g and 25 received 1 g of cefotaxime intramuscularly; 10 patients received a 30-min intravenous infusion of 2 g of cefotaxime. Samples of bronchial secretions were obtained by means of fiber-optic bronchoscopy after a single dose in all patients and after three and seven days of treatment in 30 and 15 patients, respectively. Simultaneous serum samples were collected for determination of the relationship between the levels of drug in bronchial secretions and those in serum. Assays were performed by microbiologic agar diffusion. In 30 cases bacteriologic analysis determined the minimal inhibitory concentrations of cefotaxime for the bacteria isolated from sputum. Mean peaks in bronchial secretions reached 1.5-2.5 microgram/ml (according to the groups) after 3 hr; individual concentrations varied according to the dose, the route of administration, and the duration of the treatment. Ratios between the levels in bronchial secretions and the corresponding levels in serum were approximately 8%-25% after 3 hr, as is usual for other cephalosporins. Cefotaxime reached significant concentrations in bronchial secretions, exceeding the minimal inhibitory concentrations for microorganisms responsible for respiratory infections.

[Lung tissue diffusion of intravenous trimethoprim-sulfamethoxazole combination (author's transl)]. / Diffusion pulmonaire de l'association triméthoprime-sulfaméthoxazole (TMP-SMZ).

In 13 cases of pneumonectomy, we have studied the concentration of TMP-SMZ in tissue and serum, after three days of treatment. Four hours after TMP-SMZ injection, the tissue's samples obtained from crushed and mixed ; the dosages were performed by a microbiological assay. As we previously described in bronchial secretions : the lung penetration of TMP is important ; the tissue concentrations were higher than in serum ; the diffusion of SMZ is low. The ratio of TMP to SMZ were diffusion of SMZ is low. The ratio of TMP to SMZ were different in serum and tissue, but the antibacterial activity is not affected in vitro by the value's modification.

[Penetration of cefotaxime into bronchial secretions]. / Pénétration du céfotaxime dans les sécrétions bronchiques.

The objective of this study was to evaluate the penetration into bronchial secretions, of cefotaxime, a new highly-active cephalosporin. The study was performed in 45 patients with respiratory infections. The doses and the route of administration of the drug were different in 3 groups of patients: 10 patients received 0.750 g and 20 received 1 g intramuscularly; 10 patients received a 30 min IV Infusion of 2 g of cefotaxime. Bronchial samples were taken by means of fiberoptic bronchoscopy, after a single dose in all patients, and, respectively, after 3 and 7 days treatment in 30 and 15 patients. Simultaneous serum samples were collected in order to determine relationship between bronchial and corresponding serum levels. Assays were performed by means of the microbiological agar diffusion technique. In 30 cases bacteriological analysis was performed in order to determine the MICs for cefotaxime of the bacteria isolated in sputum. The results of the study showed a mean bronchial peak reaching about 2 microgram/ml at the 3d h. Individual concentrations were varying according to doses, route of administration and underlying pathology; the ratios between bronchial and corresponding serum levels were about 15 to 23 p. cent as usual for other cephalosporins. This study indicates that cefotaxime realizes significant bronchial amounts superior to MICs of microorganisms responsible for respiratory infections.