In a new rabbit model of carbapenem-resistant Klebsiella pneumoniae knee-prosthesis infection, we studied the efficacy of colistin cement alone or in combination with systemic intramuscular (i.m.) injections of colistin.

Seven days after infection, surgical debridement and removal of the infected prostheses were performed, and rabbits were randomly assigned to one of four different treatment groups of twelve rabbits: prosthesis replacement by drug-free cement spacer (control) prosthesis replacement by colistin-loaded cement spacer (3 MUI of colistin/40 g of cement) (colistin local), prosthesis replacement by drug-free cement spacer and i.m. colistin (12 mg/kg of body weight, three time a day for 7 days), or colistin local + i.m.

We observed a statistically significant difference (p = 0.049) between the colistin local + systemic group and the control group in the criteria of number of rabbits with sterile bone under the total number of rabbits.

Combination of systemic and local colistin could be an interesting therapeutic option to cure carbapenem-resistant Klebsiella pneumoniae peri prosthetic joint infection.