SERUM AND SPUTUM CONCENTRATIONS OF AZLOCILLIN, CEFOPERAZONE AND CEFTAZIDIME IN PATIENTS WITH CYSTIC FIBROSIS

SUMMARY Single-dose pharmacokinetics of azlocillin, cefoperazone and ceftazidime were studied in 17 patients with cystic fibrosis (CF). All patients had broncho-pulmonary infections caused by Pseudomonas aeruginosa. Three groups of five, six, and six patients were treated with azlocillin, cefoperazone, or ceftazidime, respectively. The size of the single dose was 133mg/kg for azlocillin, 66u.7mg/kg for ceftazidime and 66.7 mg/kg for cefoperazone. The clearance values for the three antibiotics calculated from the single-dose data were, on the average, higher than the values previously reported for normal subjects. After the first dose, the patients received a repeated-dose treatment with the same antibiotic. During the first 5 days of therapy, a complete postural drainage of sputum was obtained four times a day for each patient. Cefoperazone could be measured in 47 (39.2%) of the 120 sputum samples assayed while ceftazidime was shown to be present in all 120 sputum samples examined. Azlocillin was not detected in any of the 100 sputum samples assayed.