Protection against Klebsiella pneumoniae respiratory tract infection of mice and squirrel monkeys given kanamycin by aerosol and injection.

The methods of aerosol administration of kanamycin and IM injection of the antibiotic were compared for their protection of mice and squirrel monkeys against Klebsiella pneumoniae respiratory tract infection. Mice exposed to LD90 of K pneumoniae at 0.5, 4, 24, 48 and 72 hours after they were treated with aerosol of kanamycin (27 mg/kg of body weight) were significantly better protected at all exposure times than were mice given the antibiotic (450 mg/kg) by IM injection. Squirrel monkeys given the aerosol at dose level of 11.25 mg/kg were completely protected against K pneumoniae exposure at 6 and 24 hours, whereas only one of eight monkeys treated with the same dose given IM survived the exposure at 6 hours and none survived at 24 hours. Antibiotic clearance curves indicated that kanamycin remained in the lungs at higher concentrations and for longer periods after aerosol treatment than after IM treatment.