Protection of tracheal explants infected with Pseudomonas aeruginosa by subinhibitory concentrations of aminoglycosides

Abstract

Mortality rates for acute pneumonias caused by Pseudomonas aeruginosa may exceed 50% [11] and antibiotic therapy remains a difficult problem. Therapy frequently includes administration of an aminoglycoside alone or in combination with a beta-lactam antibiotic. Animal studies have shown that gentamicin or tobramycin were superior to carbenicillin or ticarcillin in controlling experimental Pseudomonas pneumonia [12]. Observations have also been made in cystic fibrosis (CF) patients with chronic P. aeruginosa lung infections which indicated that the lung functions of these patients improved following therapy with aminoglycoside antibiotics although the organisms were not cleared [9]. It seemed possible, therefore, that aminoglycoside antibiotics could prevent lung damage by a mechanism that did not involve inhibition of bacterial growth.