In vivo postantibiotic effect of isepamicin and other aminoglycosides in a thigh infection model in neutropenic mice.

The object of this work is to study in neutropenic mice the in vivo postantibiotic effect (PAE) of isepamicin, a new aminoglycoside, gentamicin and netilmicin on Staphylococcus aureus and Escherichia coli and in vivo killing kinetics using two different schedules (A and B) of isepamicin and gentamicin administration against S. aureus: (A) at time zero and every hour up to the 7th or 9th hour and (B) two doses only, at time zero and at the end of the PAE. The PAE of the three aminoglycosides was long (3-5 h), showing that of isepamicin to be the largest, especially on S. aureus. Both A and B treatment models show the same effectiveness for the two tested drugs. These results support the idea that the major significance of the PAE is in its application to dosing regimens.