Clinical data showed that antimicrobial combination therapy based on CAZ-AVI in combination with gentamicin completely eradicated the infection due to cross-resistant KPC-Kp strain and that, following the BSI episode, the patient became colonized by IMI-REL-susceptible strains, which resulted clonally, related to KPC-Kp cross-resistance to IMI-REL and MER-VAB. This evidence concerns the gene NPPA and infection.