The use of aerosolized tobramycin in the treatment of a resistant pseudomonal pneumonitis.

Aerosolized tobramycin was given to a 68-year-old man with resistant Pseudomonas aeruginosa pneumonitis at a dose of 100 mg every 8 h via a tracheostomy, after the patient failed to respond adequately to parenteral aminoglycoside and ticarcillin therapy. Minimum inhibitory concentration and minimum bactericidal concentration for tobramycin and gentamicin were 16 micrograms/ml and greater than 16 micrograms/ml, which necessitated aerosol administration. Tracheal concentrations 15 min and 4 h after a dose were 1,560 and 930 micrograms/ml. The patient responded and eventually was discharged from the hospital. Thus, monotherapy with an aerosolized aminoglycoside may be effective in some patients with resistant Pseudomonas aeruginosa pneumonitis.