Imipenem/cilastatin, an alternative treatment of pseudomonas infection in cystic fibrosis.

Imipenem, a new N-formimidoyl thienamycin was given together with cilastatin to 20 patients with cystic fibrosis and pulmonary infection due to Pseudomonas aeruginosa. The antibiotic was given in short-term infusions for 9-14 days (mean 11.5) in a dose of 45-60 mg/kg body weight/day. Good clinical results were obtained in all patients with significant improvement of clinical score, pulse rate, vital capacity and FEV1.0 (P less than 0.001). Blood PO2 increased and WBC decreased significantly. A slight increase in the minimum inhibitory concentration was noted during treatment but all strains examined were fully susceptible at follow-up one month later. The peak serum concentration was significantly increased in patients receiving the high dose of imipenem, but the sputum concentration was low in all patients and there was no difference in clinical or bacteriological outcome. The plasma and urinary clearance increased with body weight and was inversely correlated to clinical score. Imipenem/cilastatin appears a good alternative for the treatment of pulmonary infections caused by P. aeruginosa in cystic fibrosis.