Experience with cefsulodin therapy for lower respiratory tract infections caused by Pseudomonas aeruginosa in adults without cystic fibrosis or granulocytopenia.

Cefsulodin was administered as the sole antipseudomonal therapy to 14 adults without cystic fibrosis or granulocytopenia for infection of the lower respiratory tract caused by susceptible strains of Pseudomonas aeruginosa. At dosages of 1.0-1.5 g intravenously every 6 hr, peak serum antipseudomonal activity consistently exceeded 1:16. Twelve patients (86%) showed a favorable therapeutic response: six (43%) with eradication of P. aeruginosa from the respiratory tract and six (43%) with persistent colonization. Two patients (14%) did not respond to cefsulodin therapy. In five cases (36%), P. aeruginosa resistant to cefsulodin appeared during the course of therapy, in two cases contributing to therapeutic failure; three strains also acquired cross-resistance to two or more other antipseudomonal beta-lactam antibiotics. Cefsulodin was well tolerated, with no evidence of organ toxicity or other adverse effects discerned. These therapeutic results are comparable with or superior to those reported with other antipseudomonal drugs studied in single-drug regimens for treatment of P. aeruginosa lower respiratory tract infections in this patient population.