The effect of triethylenetetramine dihydrochloride on the in vivo susceptibility of Pseudomonas aeruginosa to gentamicin.

A chelating agent, triethylenetetramine dihydrochloride (TRIEN dihydrochloride) increased the efficacy of gentamicin in vivo against a clinical isolate of P. aeruginosa, designated Ps 15. Mice which were inoculated with 10 X LD50 of Ps 15 and treated with doses of 2 approximately 16 mg of gentamicin per kg per day all died. However, treatment with 8 mg of gentamicin per kg body weight per day plus 30 mg of Trien dihydrochloride per day markedly reduced the mortality. The combined therapy also reduced the number of viable organisms that accumulated in the kidney during a 24-hour period post inoculation. When a dosage level of 8 mg of gentamicin was exceeded in the combined treatment regimen, all of the infected mice died, and a high concentration of endotoxin could be detected in the mouse sera by the limulus assay.